CN101076914A

CN101076914A - Laminate including active material layer and solid electrolyte layer, and all solid lithium secondary battery using the same

Info

Publication number: CN101076914A
Application number: CNA2005800426770A
Authority: CN
Inventors: 南野哲郎; 玉井秀和; 中西真二; 井上龙也; 小林惠治
Original assignee: Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Holdings Corp
Priority date: 2004-12-13
Filing date: 2005-12-12
Publication date: 2007-11-21
Anticipated expiration: 2025-12-12
Also published as: CN100495801C

Abstract

Disclosed is a multilayer body comprising an active material layer and a solid electrolyte layer which is bonded to the active material layer by sintering. The active material layer contains a crystalline first substance capable of discharging and adsorbing lithium ions, and the solid electrolyte layer contains a crystalline second substance having lithium ion conductivity. Incidentally, when this multilayer body is analyzed by an X-ray diffraction method, there is detected no component other than the constituents of the active material layer and the constituents of the solid electrolyte layer. Also disclosed is an all-solid lithium secondary battery comprising such a multilayer body and a negative electrode active material layer.

Description

Laminated body comprising active material layer and solid electrolyte layer and all solid lithium secondary battery using this laminated body

Technical field

The present invention relates to the laminated body comprising anode active material layer and solid electrolyte layer and use all solid lithium secondary battery of this laminated body.

Technical background

Electronic device is just becoming smaller and smaller, it is therefore desirable to main power source or backup power source of the battery with high-energy density as these devices.Especially lithium ion secondary battery attracts attention because it has higher voltage and higher energy density than traditional aqueous type battery.

In a lithium ion secondary battery, using oxide such as LiCoO₂、LiMn₂O₄Or LiNiO₂As positive electrode active materials, and use carbon, for example siliceous alloy or oxide (such as Li₄Ti₅O₁₂) it is used as negative electrode active material.In addition, liquid electrolyte includes the Li salt being dissolved in carbonic ester or ether type organic solvent.

But this liquid electrolyte may leak.In addition, needing to improve the safety of battery in the case where misuse because liquid electrolyte contains combustibles.In order to improve the safety and reliability of lithium ion secondary battery, face replaces all solid state lithium ion secondary cell of liquid electrolyte widely to be studied using solid electrolyte.

But solid electrolyte has the problem of conductivity and energy density are lower than liquid electrolyte.

Meanwhile in order to improve energy density, it has been suggested that a kind of stratotype battery comprising anode, the diaphragm comprising solid electrolyte or electrolyte and cathode at least one entire combination laminated body (patent document 1).The termination electrode connecting with anode and the termination electrode connecting with cathode are provided on the side of the laminated body and at least one end face of top and bottom.

In order to improve conductivity, the gel electrolyte containing liquid electrolyte can also be provided between anode active material layer and anode active material layer.

In patent document 1, every kind of combination being made of anode, solid electrolyte and cathode is connected in parallel or in series by termination electrode.Termination electrode is formed by plating, roasting or deposition, sputtering etc..But for example it is difficult to the stratotype battery by this method to contain the gel electrolyte containing liquid electrolyte.Because the water for including in plating solution enters in battery, plating cannot be used for the system comprising nonaqueous electrolyte.Because liquid electrolyte boils and evaporates, roasting is difficult to apply.In the case where deposition and sputtering, these methods need to carry out in reduced atmosphere and because liquid electrolyte also boils in the case and evaporates and be difficult to apply.

Calcium titanium-type Li_0.33La_0.56TiO₃With NASICON- type LiTi₂(PO₄)₃It is the Li ion conductor for capableing of travel at high speeds lithium ion.Recently, the all-solid-state battery using these solid electrolytes has been had developed.

It presses anode active material layer, solid electrolyte layer and anode active material layer to form laminated body by sequential layer and this laminated body is sintered by heat treatment to manufacture the solid state battery using inorganic solid electrolyte, positive electrode active materials and negative electrode active material.This method can bond the interface between interface and solid electrolyte layer and anode active material layer between anode active material layer and solid electrolyte layer.But the use of this method encounters very big disadvantage due to various reasons.

For example, the report of non-patent literature 1 is as sintering positive electrode active materials LiCoO₂With solid electrolyte LiTi₂(PO₄)₃When, they are reacted with each other during the sintering process, thus generating will not be to the contributive compound of charge/discharge reaction, such as CoTiO₃、Co₂TiO₄And LiCoPO₄。

In the case, it can occur in which the problem of sintered interface becomes electrochemicaUy inert neither active material is not the substance of solid electrolyte again due to generating at the sintered interface between active material and solid electrolyte.

Such as it has been proposed that following manufacturing method in order to solve this problem,.Firstly, preparing that there is LiMn₂O₄/Li_1.3Al_0.3Ti_1.7(PO₄)₃/Li₄Ti₅O₁₂Three layers of particle of structure.Then, it is sintered this particle at 750 DEG C and obtains electrode in 12 hours.Then, the thickness for making the polishing electrode to 10-100 μm obtains all-solid-state battery (referring to non-patent literature 2).Each layer includes the 0.44LiBO of 15 weight %₂- 0.56LiF is used as sintering aid.

But in the manufacturing method of non-patent literature 2, it cannot be sufficiently carried out sintering at a temperature of 750 DEG C so low, so that solid electrolyte and active material cannot be well-bonded at its interface.Therefore, it is shown in non-patent literature 2 in 10 μ A/cm²Under charge/discharge curve, which has obvious small current value.I.e., it is believed that the solid state battery disclosed in non-patent literature 2 has sizable internal resistance.

In this case, the internal resistance of solid state battery can be reduced by improving sintering temperature acceleration of sintering.But due to the diffusion of element, such as inertia phase is formd between active material layer and solid electrolyte layer, therefore lead to the problem of charge/discharge difficulty.

In addition, it has been proposed that manufacturing solid state battery by stacking positive electrode molding, solid electrolyte material molding and negative electrode material molding, each molding includes binder, and by microwave heating is sintered their (referring to patent documents 2).In patent document 2, molding is manufactured by forming piece or passing through silk-screen printing raw material on substrate, drying and remove substrate.

It is believed that the manufacturing method of patent document 2 can prevent respective powder in electrode and solid electrolyte layer from reacting to each other while improving filling rate.But in the case where this active material described in the embodiment such as patent document 2/solid electrolyte combination, active material and solid electrolyte inherently react to each other at high temperature, thus generate and be unable to the phase of conducting lithium ions at its interface.In this way, being still difficult to inhibit to generate inertia phase on the interface between active material and solid electrolyte even if reducing calcining time by using microwave heating.That is, according to the manufacturing method of patent document 2, it is difficult to inhibit resistance to increase on the sintered interface between active material and solid electrolyte, and capacitance loss etc. due to caused by the deterioration of active material.

Furthermore, when anode of the stacking comprising positive electrode active materials and positive electrode collector, solid electrolyte, the cathode comprising negative electrode active material and negative electrode collector are to manufacture battery, during charge/discharge the expansion and contraction of active material may the interface between active material and electrolyte and the interface between active material and collector cause leafing or may cause the rupture of battery.Due to not having stress-relieving interlayer, when using inorganic oxide as solid electrolyte, this trend is dramatically increased.

In addition, when LiTi is used alone₂(PO₄)₃When, it has undesirable sintering character, and even if being sintered at 1200 DEG C, gained lithium ion conductivity is also down to about 10^-6S/cm.Therefore, it has been reported that work as and makes LiTi₂(PO₄)₃Such as Li₃PO₄Or Li₃BO₃Sintering aid mixing when, LiTi can be sintered at 800~900 DEG C₂(PO₄)₃And improve lithium ion conductivity (referring to non-patent literature 3).

In addition, having had also been suggested that comprising lithium-phosphor-oxygen nitride compound (Li_xPO_yN_z, wherein X=2.8 and 3Z+2Y=7.8) and hull cell as solid electrolyte (referring to patent document 3).

When active material film and solid electrolyte film is formed on the substrate to prepare battery in the method for example, by sputtering, gained film is amorphous.Common active material, such as LiCoO₂、LiNiO₂、LiMn₂O₄And Li₄Ti₅O₁₂It is unable to charge or discharge in an amorphous state.Therefore, it needs to crystallize them by about 400~700 DEG C of application of heat treatment after they form film.

But because the lithium-phosphor-oxygen nitride compound used in patent document 3 decomposes at about 300 DEG C, cannot by after anode, solid electrolyte and cathode has been laminated continuous administration heat treatment crystallize active material.

In addition, using such as Ca-Ti ore type Li_0.33La_0.56TiO₃With NASICON- type LiTi₂(PO₄)₃Refractory solid electrolyte in the case of, if it is heat-treated together with common active material, interface between active material and solid electrolyte generates impurity, to be difficult to charge/discharge.

As described above, because side reaction occurs, interface between active material and solid electrolyte, which is generated, does not have contributive substance to charge/discharge, so being difficult the interface formed between active material and solid electrolyte by application heat treatment, while densifies active material layer and solid electrolyte layer and crystallizing.

Furthermore, it has been suggested that use the LiCoPO of the charge/discharge at versus lithium metal 4.8V₄As positive electrode active materials (referring to non-patent literature 4).

But liquid electrolyte due to 4.8V high work potential and decompose.Therefore, there is the problem of short life characteristic using the battery of this active material.

In addition, being very unstable to using as LiCoPO₄In this way with the active material of high work potential.

Patent document 1: Japanese Unexamined Patent Publication Hei 6-231796

Patent document 2: Japanese Unexamined Patent Publication the 2001-210360th

Patent document 3: the specification that U.S. Patent No. 5597660

Non-patent literature 1:J.Power Sources, 81-82, (1999), 853

Non-patent literature 2:Solid State Ionics 118 (1999), 149

Non-patent literature 3:Solid State Ionics, 47 (1991), 257-264

Non-patent literature 4:Electrochemical and Solid-State Letters, 3 (4), 178 (2000)

Summary of the invention

The problem to be solved in the present invention

Therefore, the object of the present invention is to provide a kind of laminated bodies, wherein since heat treatment densifies solid electrolyte layer and active material layer and crystallizes, and the interface between active material and solid electrolyte is electro-chemical activity, and provides a kind of all solid lithium secondary battery with low internal resistance and large capacity.It is a further object to provide a kind of all solid lithium secondary batteries, wherein warpage caused by by inhibiting due to sintering and embrittlement improve the adhesion strength at interface between active material layer and solid electrolyte layer.Further aim of the present invention is by inhibiting leafing, rupture etc. to provide a kind of highly reliable all solid lithium secondary battery.

Solution to the problem

The present invention relates to the laminated bodies comprising active material layer and with the solid electrolyte layer of active material layer bonding.Active material layer includes to be capable of the first substance of the crystalline form of absorption and desorption lithium ion, and solid electrolyte layer includes second of substance of crystalline form with lithium-ion-conducting.The X-ray diffraction of laminated body is analysis shows without other component other than the constituent component of the constituent component of active material layer and solid electrolyte layer.

In the laminated body, the first substance, which preferably comprises, is capable of the first phosphate cpd of the crystalline form of absorption and desorption lithium ion, and second of substance preferably comprises second of phosphate cpd of crystalline form with lithium-ion-conducting.

In the laminated body, at least solid electrolyte layer preferably has the filling rate higher than 70%.Filling rate used herein refers to the ratio of the real density of every layer of apparent density and the material of every layer of composition, is indicated by percentage.Optionally, when every layer of porosity is defined as X%, every layer of filling rate can also be defined as (100-X) %.

In the laminated body, at least one layer in active material layer and solid electrolyte layer preferably comprises amorphous oxide.In the layer comprising amorphous oxide, the amorphous oxide preferably comprises every layer of 0.1-10 weight %.In addition, the amorphous oxide preferably has 700 DEG C or higher and 950 DEG C or lower softening point.

In the laminated body, the first described phosphate cpd is preferably represented by following general formula:

LiMPO₄

Wherein M is selected from least one of Mn, Fe, Co and Ni.Second of phosphate cpd is preferably represented by following general formula:

Li_1+xM^III _xTi^IV _2-X(PO₄)₃

Wherein M^IIIIt is selected from least one of Al, Y, Ga, In and La metal ion, and 0≤x≤0.6.

The invention further relates to all solid lithium secondary battery for including at least one combined laminated body comprising anode active material layer and the solid electrolyte layer bonded with the anode active material layer.Anode active material layer includes to be capable of the first substance of the crystalline form of absorption and desorption lithium ion, and solid electrolyte layer includes second of substance of crystalline form with lithium-ion-conducting.The X-ray diffraction of laminated body is analysis shows without other component other than the constituent component of the constituent component of active material layer and solid electrolyte layer.In addition, the first substance is preferably capable of the first phosphate cpd of the crystalline form of absorption and desorption lithium ion.Second of substance is preferably second of phosphate cpd of crystalline form with lithium-ion-conducting.

In all solid lithium secondary battery, it is preferred that there is anode active material layer and solid electrolyte layer in face of the anode active material layer to be inserted in therebetween at least one combination, the solid electrolyte layer and the anode active material layer bond, and the anode active material layer includes to be capable of the third phosphate cpd of the crystalline form of absorption and desorption lithium ion or the oxide containing Ti.

In all solid lithium secondary battery, at least solid electrolyte layer preferably has the filling rate higher than 70%.

In all solid lithium secondary battery, the first described phosphate cpd is preferably represented by following general formula:

LiMPO₄

Li_1+xM^III _xTi^IV _2-X(PO₄)₃

In all solid lithium secondary battery, the third more preferably described phosphate cpd is selected from FePO₄、Li₃Fe₂(PO₄)₃And LiFeP₂O₇At least one of, and at least described solid electrolyte layer has the filling rate higher than 70%.

In all solid lithium secondary battery, the preferably described solid electrolyte includes Li_1+xM^III _xTi^IV _2-X(PO₄)₃

Wherein M^IIIIt is selected from least one of Al, Y, Ga, In and La metal ion, and 0≤x≤0.6, and the solid electrolyte layer is used as anode active material layer.

In all solid lithium secondary battery, at least one layer in active material layer and solid electrolyte layer preferably comprises amorphous oxide.In the layer comprising amorphous oxide, amorphous oxide preferably comprises every layer of 0.1-10 weight %.In addition, the amorphous oxide preferably has 700 DEG C or higher and 950 DEG C or lower softening point.

In another aspect of the present invention, at least one layer in active material layer and solid electrolyte layer preferably comprises Li₄P₂O₇。

In all solid lithium secondary battery, it can not bonded with lithium metal or collector with the solid electrolyte level of anode active material layer bonding, be inserted into the electrolyte layer of anti-reduction therebetween.

In all solid lithium secondary battery, at least one combination is preferably interposed between positive electrode collector and negative electrode collector.

In all solid lithium secondary battery, anode active material layer preferably has positive electrode collector, and anode active material layer preferably has negative electrode collector.In addition, in another aspect of the present invention, film collector is provided preferably at least one anode active material layer and anode active material layer.

In all solid lithium secondary battery, at least one collector preferably has 20% or higher and 60% or lower porosity in positive electrode collector and negative electrode collector.

Additionally, it is preferred that the center portion on active material layer thickness direction provides at least one of film positive electrode collector and film cathode collector.

In another aspect of the present invention, preferably run through at least one the anode active material layer and the anode active material layer, collector is provided in the form of three-dimensional network.

In all solid lithium secondary battery, collector be preferably provided at the opposite facing face in face of the anode active material layer contacted with the solid electrolyte layer and at least one the opposite facing face in face of the anode active material layer contacted with the solid electrolyte layer.

In all solid lithium secondary battery, preferably described at least one combination includes two or more combinations, and positive electrode collector and negative electrode collector pass through the outer collector of anode respectively and the outer collector of cathode is connected in parallel.It is highly preferred that the outer collector of anode and the outer collector of cathode include the mixture of metal and glass powder.

In all solid lithium secondary battery, positive electrode collector and negative electrode collector preferably comprise conductive material.It is highly preferred that conductive material includes selected from least one of stainless steel, silver, copper, nickel, cobalt, palladium, gold and platinum.

In all solid lithium secondary battery, preferably the laminated body is mounted in metal-back and preferred sealing metal shell.

It is preferred that covering all solid lithium secondary battery with resin.In addition, in another aspect of the present invention, the surface of all solid lithium secondary battery preferably receives water-proofing treatment.In still another aspect of the invention, all solid lithium secondary battery preferably receives water-proofing treatment, is then covered with resin.

In still another aspect of the invention, all solid lithium secondary battery preferably is covered with low-melting glass.

Moreover, it relates to the method for preparing the laminated body comprising active material layer and solid electrolyte layer.It the described method comprises the following steps: dispersing active material in the solvent comprising binder and plasticizer to form the slurry 1 for being used to form active material layer；Dispersing solid electrolyte is in the solvent comprising binder and plasticizer to form the slurry 2 for being used to form solid electrolyte layer；Active material green sheet (green sheet) is prepared using slurry 1；Solid electrolyte green sheet is prepared using slurry 2；And active material green sheet and solid electrolyte green sheet is laminated and is heat-treated them at a predetermined temperature to form laminated body.Active material includes the first phosphate cpd for capableing of absorption and desorption lithium ion, and solid electrolyte includes second of phosphate cpd with lithium-ion-conducting.

In the preparation method of the laminated body, being preferably selected from least one of slurry 1 and slurry 2 slurry includes amorphous oxide, and the predetermined temperature being heat-treated is 700 DEG C or higher and 1000 DEG C or lower.It is highly preferred that the ratio of the total amount of amorphous oxide and amorphous oxide described at least one slurry and the active material or the solid electrolyte is 0.1 weight % to 10 weight %.Amorphous oxide preferably has 700 DEG C or higher and 950 DEG C or lower softening point.

In addition, the method for the laminated body the present invention relates to preparation comprising active material layer and solid electrolyte layer.The described method comprises the following steps: position activity material forms active material layer on substrate；Deposition solid electrolyte is on active material layer to form solid electrolyte layer；And it is heat-treated active material layer and solid electrolyte layer at a predetermined temperature to crystallize.Active material includes to be capable of the first phosphate cpd of the crystalline form of absorption and desorption lithium ion, and solid electrolyte includes second of phosphate cpd of crystalline form with lithium-ion-conducting.It is preferred that depositing the active material and solid electrolyte on substrate by sputtering.

In addition, the present invention relates to a kind of methods for preparing all solid lithium secondary battery.It the described method comprises the following steps: dispersing positive electrode active materials in the solvent comprising binder and plasticizer (a) to form the slurry 1 for being used to form anode active material layer；(b) in the solvent comprising binder and plasticizer dispersing solid electrolyte to form the slurry 2 for being used to form solid electrolyte layer；(c) disperse negative electrode active material in the solvent comprising binder and plasticizer to form the slurry 3 for being used to form anode active material layer；(d) positive electrode active materials green sheet is prepared using slurry 1；(e) solid electrolyte green sheet is prepared using slurry 2；(f) negative electrode active material green sheet is prepared using slurry 3；(g) the first green sheet group including following at least one combination is formed, the combination includes: the positive electrode active materials green sheet and negative electrode active material green sheet of solid electrolyte sheet and the clamping solid electrolyte sheet；And it is heat-treated the first green sheet group at a predetermined temperature (h) to form the laminated body of at least one entire combination comprising anode active material layer, solid electrolyte layer and anode active material layer.Positive electrode active materials include to be capable of the first phosphate cpd of the crystalline form of absorption and desorption lithium ion, solid electrolyte includes second of phosphate cpd with lithium-ion-conducting, and negative electrode active material includes the third phosphate cpd for capableing of absorption and desorption lithium ion or the oxide containing Ti.

In the method for preparing all solid lithium secondary battery, amorphous oxide is preferably comprised selected from least one of slurry 1, slurry 2 and slurry 3 slurry.It is highly preferred that it is 0.1 weight % to 10 weight % that at least one slurry, which is amorphous oxide ratio shared in the total amount of the amorphous oxide and active material or solid electrolyte,.Amorphous oxide preferably has 700 DEG C or higher and 950 DEG C or lower softening point.

In addition, in the case, the predetermined temperature of heat treatment is preferably 700 DEG C or higher and 1000 DEG C or lower.

In another aspect of the present invention, Li preferably is added at least one of slurry 1, slurry 2 and slurry 3 slurry₄P₂O₇, and at 700 DEG C or higher and 1000 DEG C or be more lowly heat-treated.

The all solid lithium secondary battery preparation method the step of in (g), the combination is preferably prepared, so that selected from least one of positive electrode active materials green sheet and negative electrode active material green sheet in conjunction with collector.

In another aspect of the present invention, in step (g), the combination includes at least two positive electrode active materials green sheet, at least two negative electrode active material green sheets and solid electrolyte green sheet prepared in the manner described above prepared in the manner described above.At this point, it is preferred that being inserted into positive electrode collector between at least two positive electrode active materials green sheet, being inserted into negative electrode collector between at least two negative electrode active materials green sheet and expose one end of the positive electrode collector and one end of the negative electrode collector in the different surface region of laminated body.

In still another aspect of the invention, in step (a) and step (c), it is preferred that positive electrode collector and negative electrode collector are further mixed into slurry 1 and slurry 3 respectively, and one end of the positive electrode collector and one end of the negative electrode collector are preferably exposed in the different surface region of laminated body.

In addition, the present invention relates to prepare all solid lithium secondary battery method comprising following steps: it includes that the first of the combination being made of anode active material layer, anode active material layer and the solid electrolyte layer being inserted between anode active material layer and anode active material layer combines that (A), which is formed,；And (B) the first described combination of heat treatment at a predetermined temperature, in conjunction with and make anode active material layer, solid electrolyte layer and anode active material layer crystallization.Step (A) is the following steps are included: deposit positive electrode active materials or negative electrode active material in target substrate (i) to form the first active material layer；(ii) on first active material layer deposition solid electrolyte to form solid electrolyte layer；And second active material layer different from first active material layer is laminated in (iii) on the solid electrolyte layer, formation includes first group of the combination being made of first active material layer, solid electrolyte layer and second active material layer.Positive electrode active materials include to be capable of the first phosphate cpd of the crystalline form of absorption and desorption lithium ion, solid electrolyte includes second of phosphate cpd with lithium-ion-conducting, and negative electrode active material includes the third phosphate cpd for capableing of absorption and desorption lithium ion or the oxide containing Ti.It is preferred that passing through sputtering or thermal vapor deposition position activity material and solid electrolyte on substrate.

In addition, in the preparation method of all solid lithium secondary battery, preferred steps (iii) further include before step (B), and the step of solid electrolyte layer is to form laminated body is inserted into the combination that stacking at least two is prepared in the manner described above therebetween.

In addition, the present invention relates to the methods for preparing all solid lithium secondary battery comprising following steps: dispersing positive electrode active materials in the solvent comprising binder and plasticizer (a) to form the slurry 1 for being used to form anode active material layer；(b) in the solvent comprising binder and plasticizer dispersing solid electrolyte to form the slurry 2 for being used to form solid electrolyte layer；(c) positive electrode active materials green sheet is prepared using slurry 1；(d) solid electrolyte green sheet is prepared using slurry 2；(e) formation includes the second green sheet group of at least one combination being made of positive electrode active materials green sheet and solid electrolyte green sheet；And it is heat-treated the second green sheet group at a predetermined temperature (f) to form the laminated body of at least one entire combination comprising anode active material layer and solid electrolyte layer.It is described to combine the solid electrolyte green sheet prepared in the manner described above including at least two positive electrode active materials green sheets prepared in the manner described above and at least two in step (e).It is inserted into positive electrode collector between at least two positive electrode active materials green sheet, and is inserted into negative electrode collector between at least two solid electrolytes green sheet.Positive electrode active materials include the first phosphate cpd for capableing of absorption and desorption lithium ion.Solid electrolyte includes second of phosphate cpd with lithium-ion-conducting, and solid electrolyte is used as negative electrode active material.At least one of positive electrode collector and negative electrode collector are in the group being made of silver, copper and mickel.It is heat-treated in the atmosphere gas (atmospheric gas) of the gas comprising steam and with low oxygen partial pressure.

In the preparation method of all solid lithium secondary battery, more preferable second of phosphate cpd and the third phosphate cpd include Li_1+xM^III _xTi^IV _2-X(PO₄)₃, wherein M^IIIIt is selected from least one of Al, Y, Ga, In and La metal ion, and 0≤x≤0.6；It is heat-treated in the atmosphere gas of the gas comprising steam and with low oxygen partial pressure；The steam constitutes the 5-90 volume % of atmosphere gas；And the maximum temperature being heat-treated is 700 DEG C or higher and 1000 DEG C or lower.

In preparation laminated body and the method for all solid lithium secondary battery, the first more preferably described phosphate cpd is represented by following general formula:

LiMPO₄

Wherein M is selected from least one of Mn, Fe, Co and Ni；The first described phosphate cpd includes Fe；It is heat-treated in the atmosphere gas of the gas comprising steam and with low oxygen partial pressure；The steam constitutes the 5-90 volume % of atmosphere gas；And the maximum temperature being heat-treated is 700 DEG C or higher and 1000 DEG C or lower.

In preparation laminated body and the method for all solid lithium secondary battery, when maintaining heat treatment under T DEG C of constant temperature, oxygen balance contained in atmosphere gas divides PO₂(atmospheric pressure) more preferably meets following formula:

-0.0310T+33.5≤-log₁₀PO₂≤-0.0300T+38.1。

When being heat-treated (sintering), in scheduled heating rate's green part (greenchip), and then before its sintering, green part is made to maintain the scheduled time under scheduled constant temperature to remove no-bonder etc..In the present invention, this scheduled constant temperature is the steady temperature for maintaining heat treatment.

In preparation laminated body and the method for all solid lithium secondary battery, the gas with low oxygen partial pressure more preferably includes the mixture of the gas and the gas reacted with oxygen that can discharge oxygen.

In the preparation method of all solid lithium secondary battery, at least one of more preferable positive electrode collector and negative electrode collector include one kind selected from silver, copper and mickel；It is lower than in anodizing-reduction equilibrium oxygen partial pres-sure atmosphere gas in partial pressure of oxygen and is heat-treated；And the maximum temperature being heat-treated is 700 DEG C or higher and 1000 DEG C or lower.At this point, atmosphere gas includes carbon dioxide and hydrogen, and the partial pressure of oxygen of atmosphere gas is adjusted by changing the mixing ratio between carbon dioxide gas and hydrogen.

In the preparation method of all solid lithium secondary battery, preferably at least one of positive electrode collector and negative electrode collector include at least one selected from silver, copper and mickel；It is heat-treated in the atmosphere gas of the gas comprising steam and with low oxygen partial pressure；The steam constitutes the 5-90 volume % of atmosphere gas；And the maximum temperature being heat-treated is 700 DEG C or higher and 1000 DEG C or lower.

Effect of the invention

According to the present invention it is possible to form the interface of electro-chemical activity between active material and solid electrolyte, while densify solid electrolyte layer and active material layer by heat treatment.The life characteristic of the active material with high working voltage can also be improved.In addition, combining by using above-mentioned laminated body and at least one of cathode, all solid lithium secondary battery with small internal resistance and high capacity can be provided.In addition, all solid lithium secondary battery also when even storing in heat and wet atmosphere with height reliability can be provided by application water-proofing treatment.

Detailed description of the invention

Fig. 1 shows LiCoPO₄And Li_1.3Al_0.3Ti_1.7(PO₄)₃Mixture of powders before heat treatment after x-ray diffraction pattern；

Fig. 2 indicates LiNiPO₄And Li_1.3Al_0.3Ti_1.7(PO₄)₃Mixture of powders before heat treatment after x-ray diffraction pattern；

Fig. 3 indicates LiCoO₂And Li_1.3Al_0.3Ti_1.7(PO₄)₃Mixture of powders before heat treatment after x-ray diffraction pattern；

Fig. 4 indicates LiMn₂O₄And Li_1.3Al_0.3Ti_1.7(PO₄)₃Mixture of powders before heat treatment after x-ray diffraction pattern；

Fig. 5 indicates LiCoPO₄And Li_0.33La_0.56TiO₃Mixture of powders before heat treatment after x-ray diffraction pattern；

Fig. 6 indicates LiNiPO₄And Li_0.33La_0.56TiO₃Mixture of powders before heat treatment after x-ray diffraction pattern；

Fig. 7 indicates LiCoO₂And Li_0.33La_0.56TiO₃Mixture of powders before heat treatment after x-ray diffraction pattern；

Fig. 8 shows LiMn₂O₄And Li_0.33La_0.56TiO₃Mixture of powders before heat treatment after x-ray diffraction pattern；

Fig. 9 indicates LiCo_0.5Ni_0.5PO₄And Li_1.3Al_0.3Ti_1.7(PO₄)₃Mixture of powders before heat treatment after x-ray diffraction pattern；

Figure 10 indicates FePO₄And Li_1.3Al_0.3Ti_1.7(PO₄)₃Mixture of powders before heat treatment after x-ray diffraction pattern；

Figure 11 indicates Li₃Fe₂(PO₄)₃And Li_1.3Al_0.3Ti_1.7(PO₄)₃Mixture of powders before heat treatment after x-ray diffraction pattern；

Figure 12 indicates LiFeP₂O₇And Li_1.3Al_0.3Ti_1.7(PO₄)₃Mixture of powders before heat treatment after x-ray diffraction pattern；

Figure 13 indicates Li₄Ti₅O₁₂And Li_1.3Al_0.3Ti_1.7(PO₄)₃Mixture of powders before heat treatment after x-ray diffraction pattern；

Figure 14 indicates Nb₂O₅And Li_1.3Al_0.3Ti_1.7(PO₄)₃Mixture of powders before heat treatment after x-ray diffraction pattern；

Figure 15 indicates FePO₄And Li_0.33La_0.56TiO₃Mixture of powders before heat treatment after x-ray diffraction pattern；

Figure 16 indicates Li₃Fe₂(PO₄)₃And Li_0.33La_0.56TiO₃Mixture of powders before heat treatment after x-ray diffraction pattern；

Figure 17 indicates LiFeP₂O₇And Li_0.33La_0.56TiO₃Mixture of powders before heat treatment after x-ray diffraction pattern；

Figure 18 indicates Li₄Ti₅O₁₂And Li_0.33La_0.56TiO₃Mixture of powders before heat treatment after x-ray diffraction pattern；

Figure 19 indicates Nb₂O₅And Li_0.33La_0.56TiO₃Mixture of powders before heat treatment after x-ray diffraction pattern；

Figure 20 is the perspective illustration of the solid electrolyte green sheet formed on film carrier；

Figure 21 is the perspective illustration of the active material green sheet formed on film carrier；

Figure 22 is placed on solid electrolyte green sheet on the carrier with polyester film and film carrier

Illustrate longitudinal sectional view；

Figure 23 is the signal longitudinal sectional view for therefrom having eliminated the solid electrolyte green sheet of film carrier；

Figure 24 is placed on the signal longitudinal sectional view of 20 solid electrolyte green sheets and 1 active material green sheet on the carrier with polyester film；

Figure 25 is the signal longitudinal sectional view for being clipped in the green part of the two panels stacking among ceramic wafer；

Figure 26 is the signal longitudinal sectional view of green part (laminated body i.e. of the invention) and the gold thin film formed above of sintering；

Figure 27 is the signal longitudinal sectional view of battery 1；

Figure 28 is the signal longitudinal sectional view of all solid lithium secondary battery in another embodiment of the invention；

Figure 29 is the perspective illustration of the solid electrolyte green sheet formed on film carrier；

Figure 30 is the perspective illustration of the positive electrode active materials green sheet formed on film carrier；

Figure 31 is the perspective illustration of the negative electrode active material green sheet formed on film carrier；

Figure 32 is placed on the signal longitudinal sectional view of negative electrode active material green sheet and film carrier on the carrier with polyester film；

Figure 33 is the signal longitudinal sectional view for therefrom having eliminated the negative electrode active material green sheet of film carrier；

Figure 34 is the signal longitudinal sectional view of the negative electrode active material green sheet being layered on the carrier with polyester film, 20 solid electrolyte green sheets and positive electrode active materials green sheet；

Figure 35 is the signal longitudinal sectional view for being clipped in the green part of the two panels stacking among ceramic wafer；

Figure 36 is the laminated body of sintering and the signal longitudinal sectional view (battery 7) of the gold thin film formed above；

Figure 37 is the signal longitudinal sectional view of the battery 11 prepared in example 4；

Figure 38 is the signal longitudinal sectional view of the battery 18 prepared in embodiment 6；

Figure 39 is the signal longitudinal sectional view of the battery 19 prepared in embodiment 6；

Figure 40 is the perspective illustration of the solid electrolyte green sheet formed on film carrier；

Figure 41 is the diagrammatic top view for the multi-disc positive electrode active materials green sheet being arranged on film carrier in a predetermined pattern；

Figure 42 is the diagrammatic top view for the multi-disc positive electrode collector green sheet being arranged on film carrier in a predetermined pattern；

Figure 43 is the diagrammatic top view for the multi-disc negative electrode active material green sheet being arranged on film carrier in a predetermined pattern；

Figure 44 is the diagrammatic top view for the multi-disc negative electrode collector green sheet being arranged on film carrier in a predetermined pattern；

Figure 45 is placed on the signal longitudinal sectional view of solid electrolyte green sheet and film carrier on the carrier with polyester film；

Figure 46 is the signal longitudinal sectional view for therefrom having eliminated the solid electrolyte green sheet of film carrier；

Figure 47 is the signal longitudinal sectional view for 20 solid electrolyte green sheets being layered on the carrier with polyester film；

Figure 48 is the signal longitudinal sectional view for the multi-disc negative electrode active material green sheet being supported on film carrier surface, they are layered in the solid electrolyte green sheet formed on film carrier；

Figure 49 is the signal longitudinal sectional view of the negative electrode active material green sheet being layered in the solid electrolyte green sheet, negative electrode collector green sheet and negative electrode active material green sheet；

Figure 50 is the signal longitudinal sectional view for the multi-disc positive electrode active materials green sheet being supported on film carrier surface, they are layered in the solid electrolyte green sheet formed on film carrier；

Figure 51 is the signal longitudinal sectional view of the positive electrode active materials green sheet being layered in the solid electrolyte green sheet, positive electrode collector green sheet and positive electrode active materials green sheet；

Figure 52 is the signal longitudinal sectional view of the laminated body of negative electrode active material green sheet on supported solid electrolyte green sheet surface, negative electrode collector green sheet and negative electrode active material green sheet, and the laminated body is layered on solid electrolyte green compact sheet laminate；

Figure 53 is the signal longitudinal sectional view of five cathode laminated bodies being alternately laminated on solid electrolyte green compact sheet laminate and four positive laminated bodies；

Figure 54 is the top view by cutting the green part that the laminated body piece obtains；

Figure 55 is the signal longitudinal sectional view along the green part of line X-X Figure 54 obtained；

Figure 56 is the signal longitudinal sectional view along the green part of line Y-Y Figure 54 obtained；

Figure 57 is that have the signal longitudinal sectional view of the sintered body of collector outside the outer collector of anode and cathode in the endface of the end face of exposure positive electrode collector and exposure negative electrode collector respectively；

Figure 58 is the diagrammatic top view of the positive electrode active materials green sheet in the solid electrolyte green sheet being arranged on film carrier in a predetermined pattern；

Figure 59 is the diagrammatic top view of the negative electrode active material green sheet in the solid electrolyte green sheet being arranged on film carrier in a predetermined pattern；

Figure 60 is the signal longitudinal sectional view for the negative electrode active material green sheet (being layered on solid electrolyte green compact sheet laminate) being supported on solid electrolyte green sheet surface；

Figure 61 is five negative electrode tabs being layered on solid electrolyte green compact sheet laminate and the signal longitudinal sectional view of four positive plates；

Figure 62 is the top view by cutting the green part that the laminated body piece obtains；

Figure 63 is the signal longitudinal sectional view along the green part of line X-X Figure 62 obtained；

Figure 64 is the signal longitudinal sectional view along the green part of line Y-Y Figure 62 obtained；

Figure 65 is that have the signal longitudinal sectional view of the sintered body of collector outside the outer collector of anode and cathode in the endface of the end face of exposure anode active material layer and exposure anode active material layer respectively；

Figure 66 is the signal longitudinal sectional view of the sintered body covered with the part other than the part of the outer collector of anode and the outer collector covering of cathode with glassy layer；

Figure 67 is the perspective illustration of the solid electrolyte green sheet formed on film carrier；

Figure 68 is the diagrammatic top view for the multi-disc positive electrode active materials green sheet being arranged on film carrier in a predetermined pattern；

Figure 69 is the diagrammatic top view for the multi-disc positive electrode collector green sheet being arranged on film carrier in a predetermined pattern；

Figure 70 is the diagrammatic top view for the multi-disc negative electrode collector green sheet being arranged on film carrier in a predetermined pattern；

Figure 71 is placed on the signal longitudinal sectional view of solid electrolyte green sheet and film carrier on the carrier with polyester film；

Figure 72 is the signal longitudinal sectional view for therefrom having eliminated the solid electrolyte green sheet of film carrier；

Figure 73 is the signal longitudinal sectional view for 20 solid electrolyte green sheets being layered on the carrier with polyester film；

Figure 74 is the signal longitudinal sectional view for the multi-disc negative electrode collector green sheet being supported on film carrier surface, they are laminated in the solid electrolyte green sheet for being to be formed on film carrier；

Figure 75 is the negative electrode active material green sheet being layered in solid electrolyte green sheet and the signal longitudinal sectional view of negative electrode collector green sheet；

Figure 76 is the signal longitudinal sectional view for the multi-disc positive electrode collector green sheet being supported on film carrier surface, they are laminated in the solid electrolyte green sheet for being to be formed on film carrier；

Figure 77 is the signal longitudinal sectional view of the positive electrode active materials green sheet being layered in solid electrolyte green sheet, positive electrode collector green sheet and positive electrode active materials green sheet；

Figure 78 is the signal longitudinal sectional view for the negative electrode collector green sheet being supported on solid electrolyte green sheet surface, they are layered on solid electrolyte green compact sheet laminate；

Figure 79 is the signal longitudinal sectional view of five cathode-solid electrolyte sheets being alternately laminated on solid electrolyte green compact sheet laminate and four positive laminated bodies；

Figure 80 is the top view by cutting the green part that the laminated body piece obtains；

Figure 81 is the signal longitudinal sectional view along the green part of line X-X Figure 80 obtained；

Figure 82 is the signal longitudinal sectional view along the green part of line Y-Y Figure 80 obtained；

Figure 83 is that have the signal longitudinal sectional view of the sintered body of collector outside the outer collector of anode and cathode in the endface of the end face of exposure positive electrode collector and exposure negative electrode collector respectively.

Specific embodiment

Laminated body (hereinafter referred to as the first laminated body) of the invention includes active material layer and the solid electrolyte layer with active material layer bonding.

Active material layer includes to be capable of the first substance of the crystalline form of absorption and desorption lithium ion, and solid electrolyte layer includes second of substance of crystalline form with lithium-ion-conducting.The X-ray diffraction of laminated body is analysis shows without other component other than the constituent component of the constituent component of active material layer and solid electrolyte layer.

In addition, the active material layer and solid electrolyte are preferably crystalline form.

With in the standby battery of this laminated body, anode includes the active material layer.

The first substance for including in active material layer, which for example can be, is capable of the first phosphate cpd of the crystalline form of absorption and desorption lithium ion.The first described phosphate cpd is preferably represented by following general formula:

LiMPO₄

Wherein M is selected from least one of Mn, Fe, Co and Ni.

In addition, second of substance for including in solid electrolyte layer can be second of phosphate cpd of crystalline form with lithium-ion-conducting.Second of phosphate cpd is preferably represented by following general formula:

Li_1+xM^III _xTi^IV _2-X(PO₄)₃

When using the active material layer comprising this active material and comprising the solid electrolyte layer of this solid electrolyte, even if can also inhibit to generate at the bonding interface (bonding interface i.e. between active material and solid electrolyte) between the first described substance and second of substance is not that active material is also not solid electrolyte and does not have contributive impurity phase to charge/discharge reaction in laminated body for middle application heat treatment.

For the all-solid-state battery for capableing of charge/discharge, needs to maintain lithium-ion-conducting at the bonding interface between active material and solid electrolyte and be over a large area firmly bonded to active material layer and solid electrolyte layer together.The combination of active material layer and solid electrolyte layer according to the present invention is able to carry out this interfacial adhesion.

Active material layer and solid electrolyte layer preferably all have lithium-ion-conducting.Additionally, it is preferred that at least solid electrolyte layer has 70% or more solid electrolyte filling rate.Again it is preferred to which active material layer has 70% or more active material filling rate.For example, if filling rate may have undesirable charge/discharge characteristics less than 70%, with the standby battery of this laminated body of the present invention.

Preferably, active material layer and solid electrolyte layer are all free of the organic substance of such as organic binder, because of the electronic conductivity or ionic conductivity of organic substance damage active material layer and solid electrolyte layer.That is, they are preferably deposition film or sintered membrane.

In the first laminated body, the thickness x of active material layer₁Preferably 0.1-10 μm.If the thickness x of active material layer₁Less than 0.1 μm, the battery with enough capacity cannot be obtained.If the thickness x of active material layer₁Greater than 10 μm, this battery charging and discharging are difficult.

In addition, the thickness y of solid electrolyte layer can be in a wider scope.The thickness y of solid electrolyte layer preferably about 1 μm of -1cm, and more preferably 10-500 μm.This is because while solid electrolyte layer is preferably thin for energy density, but solid electrolyte layer is needed with mechanical strength.

In laminated body of the invention, at least one layer in active material layer and solid electrolyte layer preferably comprises amorphous oxide.

In general, being sintered different ceramic materials (i.e. the first phosphate cpd and the second phosphate cpd) at different temperature.Therefore, when making the laminated body of a variety of different ceramic materials receive heat treatment sintering, the sintering of material starts at different temperature or carries out at different speeds.It may become fragile when the sintering of each layer starts perhaps to carry out at different speeds at different temperature since in sintering warpage or laminated body may occur for thermal strain.In addition, the interface of active material layer and solid electrolyte interlayer may separate.It is therefore preferable that amorphous oxide should be added as sintering aid in the active material layer or solid electrolyte layer of acceleration of sintering.As a result, the sintering start temperature of each layer and sintering velocity can for example be made to become identical.Therefore, it may be decreased warpage or interfacial separation of embrittlement, active material layer and solid electrolyte layer of the laminated body occurred when being sintered laminated body etc..By changing the type (softening point) of amorphous oxide, adjustable sintering start temperature etc., and pass through change additive amount, adjustable sintering velocity etc..

In addition, stating laminated body in use in all-solid-state battery, when adding amorphous oxide at least one active material layer and solid electrolyte layer, the impedance of all-solid-state battery can be reduced.It is this that there is excellent high magnification (high rate) characteristic with low-impedance battery.

The example of this amorphous oxide includes comprising SiO₂、Al₂O₃、Na₂O, MgO and CaO, 72 weight %SiO₂- 1 weight %Al₂O₃- 20 weight %Na₂O-3 weight %MgO-4 weight %CaO, 72 weight %SiO₂- 1 weight %Al₂O₃- 14 weight %Na₂O-3 weight %MgO-10 weight %CaO and 62 weight %SiO₂- 15 weight %Al₂O₃The oxide of -8 weight %CaO-15 weight %BaO.

By adding alkali metal, alkaline-earth metal or rare earth metal into amorphous oxide or by changing its content, thus it is possible to vary the softening point of amorphous oxide.

In addition, the amount of amorphous oxide is preferably the 0.1 weight % or higher and 10 weight % or lower of layer in the layer of addition amorphous oxide.If the amount of amorphous oxide is lower than 0.1 weight %, amorphous oxide cannot generate the effect of acceleration of sintering.If the amount of amorphous oxide is more than 10 weight %, the amorphous object amount in layer is excessive, so that the electrochemical properties of battery may be decreased.

Next, illustrating all solid lithium secondary battery of the invention.

It includes at least one combined laminated body (hereinafter referred to as the second laminated body) being made of anode active material layer, anode active material layer and the solid electrolyte layer being inserted between anode active material layer and anode active material layer that all solid lithium secondary battery of the invention, which has,.In all solid lithium secondary battery of the invention, near few anode active material layer and solid electrolyte layer are bonded together (whole).That is, above-mentioned first laminated body is used as anode active material layer and solid electrolyte layer in the second laminated body.

In the case, further preferably at least solid electrolyte layer have 70% or more filling rate.Equally, anode active material layer preferably has 70% or more filling rate.

According to mode identical with the first laminated body, anode active material layer is for example comprising the first for example above-mentioned phosphate cpd of the first substance, and solid electrolyte layer is for example comprising for example above-mentioned second of the phosphate cpd of second of substance.Negative electrode active material can be for example made of the material that can be used with plate-like form.The example of this material includes lithium metal, Al, Sn and In.

The thickness of anode active material layer is preferably 500 μm or smaller.

In addition, in the first described phosphate cpd, by general formula LiMPO₄The compound of representative usually has high work potential, and wherein M is selected from least one of Mn, Fe, Co and Ni.Thus, for example as positive electrode active materials and using lithium metal as negative electrode active material by using the first phosphate cpd represented by above-mentioned general formula, the battery with high working voltage can be obtained.

In addition, being used as in second of phosphate cpd of solid electrolyte, it is known that by Li_1+xM^III _xTi^IV _2-X(PO₄)₃The compound of representative is in opposite Li/Li⁺It is reduced electrochemically under electrode about 2.5V, wherein M^IIIIt is selected from least one of Al, Y, Ga, In and La metal ion and 0≤x≤0.6.Therefore, the opposite Li/Li of operating voltage is being used⁺In the case where electrode is about 2.5V or lower active material, in order to prevent it from being reduced, provided preferably between solid electrolyte layer and cathode comprising the anti-layer for going back original electrolyte.In this case, it is possible to obtain the solid state battery with excellent reliability.

The anti-original electrolyte of going back can be conventional polymer electrolyte in related fields.The example of these polymer dielectrics includes: comprising the gel electrolyte with electrolyte-impregnated and the polymer body (polymer host) of swelling, and the polymer body is, for example, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate or polyethers；And dry polymeric, the dry polymeric dissolve Li salt, such as LiPF by the way that polyethylene oxide base polyethers to be copolymerized with the siloxanes, acrylic acid type compound or polyhydroxy-alcohol for being used as branch in the copolymer₆、LiClO₄、LiBF₄Or LiN (SO₂CF₃)₂To obtain.

Example for preparing the electrolyte of gel electrolyte is wherein in the solvent mixture comprising two or more solvents (such as ethylene carbonate, propylene carbonate, dimethoxy-ethane, dimethyl carbonate, ethyl methyl carbonate and diethyl carbonate) dissolved with Li salt (such as LiPF₆、LiClO₄、LiBF₄Or LiN (SO₂CF₃)₂) electrolyte.

For example, the layer comprising this gel electrolyte can be formed in solid electrolyte layer surface as follows.

Polymer body is separately dissolved in advance in organic solvent, such as acetonitrile, 2- methyl-pyrrolidon, 1,2- dimethoxy-ethane or dimethylformamide.The solution is administered in solid electrolyte layer surface for example, by the method for casting or spin coating and drying forms film.Then, add on the film as described above includes the liquid electrolyte of Li salt to cause the gelling of film.In this way, gel electrolyte layer can be formed in solid electrolyte layer surface.

Furthermore it is possible to form the layer comprising dry polymeric according to method identical with gel electrolyte.Specifically, the copolymer comprising above-mentioned polyethers for wherein having dissolved Li salt is dissolved in organic solvent, such as acetonitrile, 2- methyl-pyrrolidon, 1,2- dimethoxy-ethane or dimethylformamide.Acquired solution is administered in solid electrolyte layer surface for example, by the method for casting or spin coating, is then dried.In this way, dry polymeric layer can be formed in solid electrolyte layer surface.

Battery of the invention can be constructed, so that negative electrode collector is provided directly on anti-reduction electrolyte layer and does not provide cathode between anti-reduction electrolyte layer and negative electrode collector.When making this battery charge, the lithium ion for including in positive electrode active materials is deposited on negative electrode collector as lithium metal, and the lithium metal may be used as cathode.

In addition, in all solid lithium secondary battery of the invention, preferably in combination with anode active material layer, solid electrolyte layer and anode active material layer.When combining anode active material layer, solid electrolyte layer and anode active material layer, negative electrode active material preferably comprises the third phosphate cpd for capableing of absorption and desorption lithium ion.The third described phosphate cpd is preferably selected from FePO₄、Li₃Fe₂(PO₄)₃And LiFeP₂O₇At least one of.

In addition, anode active material layer for example may include Li₄Ti₅O₁₂As active material.In the case, Li can be used for example_0.33La_0.56TiO₃As solid electrolyte.

In addition, the crystalline form that anode active material layer, solid electrolyte layer and anode active material layer are preferably all.

Using this negative electrode active material, the not only interface between positive electrode active materials and solid electrolyte, and also the interface between anolyte and solid electrolyte can inhibit to react charge/discharge the generation for not having contributive impurity phase.In addition, can maintain lithium ion conductivity in these interfaces and can in large area be firmly bonded to active material layer and solid electrolyte layer together.I.e., it is possible to reduce the internal resistance of all solid lithium secondary battery and improve reliability.

In the case, the thickness x of anode active material layer₃Preferably 0.1-10 μm.If the thickness x of active material layer₃Less than 0.1 μm, the battery with enough capacity cannot be obtained.If the thickness x of active material layer₃Greater than 10 μm, this battery charging and discharging are difficult.

The thickness x of anode active material layer₁Preferably 0.1-10 μm.The thickness y of solid electrolyte layer preferably about 1 μm of -1cm, and 10-500 μm is preferred.Reason is same as described above.

In addition, preferably various combinations are bonded together in the second laminated body for including one or more said combinations.Because including one or more said combinations, it is possible to increase battery capacity.In addition, because combining various combinations, it is possible to reduce the internal resistance of all solid lithium secondary battery.

In the case, further preferably every kind of anode active material layer, solid electrolyte layer and anode active material layer all with 70% or more filling rate.

In addition, all solid lithium secondary battery of the invention may include positive electrode collector and negative electrode collector.

Such as, positive electrode collector can be provided on the opposite facing face in face contacted with the solid electrolyte layer with the anode active material layer, and negative electrode collector can be provided on the opposite facing face in face contacted with the solid electrolyte layer with the anode active material layer.In the case, such as after foring the laminated body positive electrode collector and negative electrode collector are provided.

In addition, positive electrode collector and/or negative electrode collector can be made of conductive material well known in related fields (such as scheduled metallic film) when forming positive electrode collector and negative electrode collector after foring said combination.

In addition, when two kinds or more kinds of said combinations is laminated, anode active material layer and anode active material layer in all solid lithium secondary battery can separately include positive electrode collector and negative electrode collector in all solid lithium secondary battery of the invention.At this point, positive electrode collector can be the form of film or three-dimensional network.

When two kinds or more kinds of combinations are laminated as described above, the negative electrode collector in positive electrode collector and each anode active material layer in each anode active material layer can be connected in parallel by the outer collector of anode and the outer collector of cathode respectively.At this point, it is preferred that exposing one end of positive electrode collector and one end of negative electrode collector at two kinds or at the different sides of more kinds of combined laminated bodies.For example, the second laminated body of two kinds or more kinds of combinations is hexahedron, one end of positive electrode collector can be exposed at the predetermined face of laminated body, and can with expose positive electrode collector one end the opposite facing face in face at exposure negative electrode collector.

It is preferred that covering part of the second laminated body surface other than the part covered with collector outside collector other than anode and cathode with solid electrolyte layer.In the case, the outer collector of the outer collector of anode, cathode and solid electrolyte layer are used as external jacket.

The outer collector of anode and the outer collector of cathode can include the mixture with the metal material of electronic conductivity and the glass powder of heat-fusibleization.Although usually using copper as metal material, other metals also can be used.It is about 400-700 DEG C of glass powder with low melting point using softening point.

When providing positive electrode collector and negative electrode collector during preparing said combination, it is preferred that positive electrode collector and negative electrode collector can be heat-treated in the identical atmosphere of processing atmosphere with anode active material layer, solid dielectric layer and anode active material layer, and do not reacted with positive electrode active materials and negative electrode active material.

The material of positive electrode collector and negative electrode collector is preferably selected from least one of silver, copper, nickel, palladium, gold and platinum.When being heat-treated in atmosphere gas (air), because silver, copper and mickel may be reacted with active material, palladium, gold and platinum are preferred.

In addition, the active material layer of identical type is laminated, is inserted into collector therebetween when using two or more said combinations.In this way, positive electrode collector and negative electrode collector can be provided to all solid lithium secondary battery.Such as, when three kinds of combinations of the first combination, second of combination and the third combination are laminated, the anode active material layer and second of combined anode active material layer of the first combination are loaded on the two sides of positive electrode collector, and the anode active material layer of second of combined anode active material layer and the third combination is loaded on the two sides of negative electrode collector.In this way, positive electrode collector and negative electrode collector can be provided to all solid lithium secondary battery.

In addition, including Li in use_1+xM^III _xTi^IV _2-X(PO₄)₃Solid electrolyte layer in the case where, wherein M^IIIIt is that may be used as negative electrode active material selected from least one of Al, Y, Ga, In and La metal ion and 0≤x≤0.6, the solid electrolyte.This solid electrolyte can be in opposite Li/Li⁺Absorption and desorption Li under about 2.5V.

In addition, in all solid lithium secondary battery, it is including especially all solid lithium secondary battery of the laminated body of multiple said combinations, at least one collector preferably has 20% or bigger and 60% or smaller porosity in positive electrode collector and negative electrode collector.

When being inserted into charge/discharge and discharging lithium, the volume of active material usually increases and reduces.Even when the stereomutation of active material, if collector has hole, hole may be used as buffer layer.Therefore leafing, the rupture etc. of interface between the collector and active material of the all-solid-state battery can be inhibited.

If the porosity of collector is less than 20%, it will be difficult to mitigate the volume change of active material, so that battery may be susceptible to rupture.If the porosity of collector is greater than 60%, the ability of collector collected current is reduced, so battery capacity may be decreased.

In addition, positive electrode collector is not preferably reacted with positive electrode active materials, and negative electrode collector is not preferably reacted with negative electrode active material.Additionally, it is preferred that positive electrode collector and negative electrode collector can be heat-treated in identical atmosphere simultaneously with positive electrode active materials, solid electrolyte and negative electrode active material.

The material of positive electrode collector and negative electrode collector is, for example, silver, copper, nickel, cobalt or stainless steel.

But because silver, copper, nickel, cobalt and stainless steel be to active material it is highly reactive, the atmosphere in laminated body calcination steps must be controlled.It is therefore preferable that using the collector made of platinum, gold or palladium.

Additionally, it is preferred that being inserted into positive electrode collector in the form of layer in anode active material layer center portion, and it is inserted into negative electrode collector in the form of layer in anode active material layer center portion.

In all solid lithium secondary battery of the invention, as in the first laminated body, at least one layer in anode active material layer, solid electrolyte layer and anode active material layer may include amorphous oxide.In addition, the amount of amorphous oxide is preferably the 0.1 weight % or bigger and 10 weight % or smaller of layer in the layer comprising amorphous oxide.Reason is same as described above.

As described above, the impedance of the all-solid-state battery can be reduced comprising amorphous oxide in at least one layer in anode active material layer, solid electrolyte layer and anode active material layer, thus lead to the improvement of high-rate characteristics.

Furthermore it is possible to be sintered Li together with the first phosphate cpd, second of phosphate cpd or the third phosphate cpd₄P₂O₇.Therefore, at least one layer in anode active material layer, solid electrolyte layer and anode active material layer may include Li₄P₂O₇.Li with 876 DEG C of fusing points₄P₂O₇It is used as sintering aid in 700 DEG C or more relative superiority or inferiority.It therefore, include Li in at least one layer in anode active material layer, anode active material layer and solid electrolyte layer₄P₂O₇Allow sinter layer in an improved way.As described above, because Li₄P₂O₇With amorphous oxide effect having the same, it is possible to be handled according to mode identical with amorphous oxide.

Next, illustrating the method for preparing first laminated body.

Such as the first laminated body can be prepared as follows.

Firstly, dispersing active material in the solvent comprising binder and plasticizer to form the slurry 1 for being used to form active material layer.Equally, in the solvent comprising binder and plasticizer dispersing solid electrolyte to form the slurry 2 (step (1)) for being used to form solid electrolyte layer.Active material is for example comprising the first phosphate cpd, and solid electrolyte is for example comprising second of phosphate cpd.

It can disperse or dissolve binder and plasticizer in a solvent.

Next, slurry 1 is administered on the target substrate for example with releasing agent layer (such as piece or film), and dry acquisition active material green sheet.Equally, slurry 2 is administered in target substrate and drying obtains solid electrolyte green sheet (step (2)).

Then, the active material green sheet so obtained and solid electrolyte green sheet is laminated and is heat-treated (sintering), to obtain the first laminated body (step (3)) comprising active material layer and solid electrolyte layer.

Because the organic substance for including in active material green sheet and solid electrolyte green sheet, such as binder and plasticizer decompose during sintering, so being free of organic substance in the active material layer and solid electrolyte layer of gained laminated body.

In addition, passing through the filling rate for adjusting the adjustable active material layers and solid electrolyte layer such as maximum sintering temperature, the rate of heat addition.Maximum sintering temperature is preferably in the range of 700 DEG C to 1000 DEG C.If maximum sintering temperature is lower than 700 DEG C, sintering not can be carried out.If maximum sintering temperature is higher than 1000 DEG C, Li may be evaporated from compound containing Li, the variation for causing composition containing Li to form, or the phase counterdiffusion of active material and solid electrolyte may occur, so as to cause charge/discharge failure.In addition, the rate of heat addition is preferably 400 DEG C/h or higher.If the rate of heat addition is lower than 400 DEG C/h, it may occur however that the phase counterdiffusion of active material and solid electrolyte, so as to cause charge/discharge failure.

It, can be to adding above-mentioned amorphous oxide at least one of slurry 1 and slurry 2 in addition, in step (1).

The softening point of added amorphous oxide is preferably almost the same with the sintering start temperature of active material layer or solid electrolyte layer (whichever most easy-sintering).For example, when active material layer includes LiCoPO₄When, this anode active material layer most easy-sintering, and it is preferred that therefore the softening point of amorphous oxide is almost the same with the sintering start temperature of active material layer.Furthermore it is possible to the softening temperature of amorphous oxide be adjusted, so that it is almost the same with maximum sintering temperature.

In the present invention, the softening point of amorphous oxide is preferably 700 DEG C or higher and 950 DEG C or lower.

Further, it is also possible to prepare the first laminated body in the following way.

Firstly, on scheduled substrate position activity material formed active material layer, and on the active material layer deposition solid electrolyte to form solid electrolyte layer (step (1 ')).It can implement the deposition of active material and solid electrolyte by sputtering.

Next, active material layer and solid electrolyte layer are heat-treated at a predetermined temperature to crystallize, to obtain the first laminated body (step (2 ')).

In step (2 '), being heat-treated active material layer and solid electrolyte layer come the temperature crystallized is preferably 500 DEG C -900 DEG C.If the temperature is lower than 500 DEG C, crystallization may be difficult.If it is higher than 900 DEG C, the phase counterdiffusion of active material and solid electrolyte may be reinforced.

The laminated body so obtained does not have the third layer of interference lithium ion movement between active material layer and solid electrolyte layer.

In the preparation method of laminated body, active material for example can be the first substance of such as the first phosphate cpd.Solid electrolyte can be second of substance of such as second phosphate cpd.

Next, illustrating the preparation method of all solid lithium secondary battery of the invention.

By forming anode active material layer in the first laminated body prepared in the manner described above, make it in face of anode active material layer, it is inserted into solid electrolyte layer therebetween, all solid lithium secondary battery with the second laminated body for including at least one combination being made of the first laminated body and anode active material layer can be prepared.When all solid lithium secondary battery includes multiple said combinations, such as each combination is laminated, and be inserted into solid electrolyte layer therebetween.

In addition, as described above, anti-reduction electrolyte layer is formed on solid electrolyte layer before forming anode active material layer when providing anti-reduction electrolyte layer between solid electrolyte layer and anode active material layer.The layer can be formed by various methods without any specifically limited.

Next, explanation includes the preparation method of all solid lithium secondary battery of the second laminated body, anode active material layer, solid electrolyte layer and anode active material layer are combined in the second laminated body.For example, this all solid lithium secondary battery can be prepared as follows.

Firstly, dispersing positive electrode active materials in the solvent comprising binder and plasticizer to form the slurry 1 for being used to form anode active material layer.Equally, dispersing solid electrolyte is in the solvent comprising binder and plasticizer to form the slurry 2 for being used to form solid electrolyte layer, and disperses negative electrode active material in the solvent comprising binder and plasticizer to form the slurry 3 (step (a)) for being used to form anode active material layer.Positive electrode active materials are for example comprising the first above-mentioned phosphate cpd, and solid electrolyte is for example comprising above-mentioned second of phosphate cpd, and negative electrode active material is for example comprising the third above-mentioned phosphate cpd or oxide containing Ti.

Then, slurry 1 is administered on the target substrate for example with releasing agent layer (such as piece or film), and drying forms positive electrode active materials green sheet.In addition, forming negative electrode active material green sheet and solid electrolyte green sheet (step (b)) in the same manner.

Then, the first green sheet group is formed comprising at least one combination, which includes: solid electrolyte green sheet；And the positive electrode active materials green sheet and negative electrode active material green sheet (step (c)) of the clamping solid electrolyte green sheet.When using multiple said combinations, such as it is inserted under solid electrolyte layer therebetween and these combinations is laminated.

Then, it is sintered the first green sheet group at a predetermined temperature, formation includes the second laminated body (step (d)) for at least one combination being made of anode active material layer, solid electrolyte layer and anode active material layer.The first described phosphate cpd, second of phosphate cpd and the third phosphate cpd are all crystalline forms, therefore when being sintered them, each layer becomes crystalline form.

It should be understood that because the organic substance for including in active material green sheet and solid electrolyte green sheet, such as binder and plasticizer decompose during sintering, so being free of organic substance in the active material layer and solid electrolyte layer of gained laminated body.

In addition, according to mode same as above, by the filling rate for adjusting the adjustable active material layers and solid electrolyte layer such as maximum sintering temperature, the rate of heat addition.Maximum sintering temperature is preferably in the range of 700 DEG C to 1000 DEG C, and the rate of heat addition is preferably 400 DEG C/h or higher.Reason is same as described above.

In addition, in step (a) above-mentioned amorphous oxide can be added at least one of slurry 1, slurry 2 and slurry 3.For example, when positive electrode active materials green sheet, negative electrode active material green sheet and solid electrolyte green sheet have different sintering velocities amorphous oxide can be added into the slurry for being used to form two kinds of green sheets under lower sintering velocity.In addition, when the sintering velocity difference in each green sheet is small amorphous oxide can be added into the slurry for be used to form green sheet under minimum sintering velocity.

When positive electrode active materials, solid electrolyte and negative electrode active material are above-mentioned phosphate cpd and their partial size is almost the same, the sintering start temperature of solid electrolyte green sheet is intended to higher than positive electrode active materials green sheet and negative electrode active material green sheet.In the case, therefore preferably amorphous oxide is added into the slurry for be used to form solid electrolyte layer.

In the slurry comprising amorphous oxide, the amount of amorphous oxide is preferably the 0.1-10 weight % of slurry.Reason is same as described above.

In step (d), it include anode active material layer, the laminated body of solid electrolyte layer and anode active material layer, preferably heat treatment positive electrode active materials green sheet, the laminated body of solid electrolyte green sheet and negative electrode active material green sheet to obtain.Reason is same as described above.For example, the laminated body of heat treatment positive electrode active materials green sheet and solid electrolyte green sheet, then forms negative electrode active material green sheet on the opposite facing face in face contacted with anode active material layer with solid electrolyte layer.In order to bond further heat treatment gained laminated body.In the case, solid electrolyte layer is sufficiently sintered, but negative electrode active material green sheet is shunk due to sintering, so that solid electrolyte layer and anode active material layer cannot be bonded together and may separate in its interface.

Positive electrode collector and negative electrode collector can be arranged to clamp second laminated body.Optionally, each anode active material layer and/or each anode active material layer may have collector.

When arranging that positive electrode collector and negative electrode collector make it clamp second laminated body, positive electrode collector and negative electrode collector are arranged on two end faces of second laminated body in the stacking direction.

In this case, it is possible to form collector as follows.

Conductive layer is formed for example, the paste containing above-mentioned conductive material is administered on active material layer and is dried, and this layer can be used as collector.In addition, forming the metal layer comprising above-mentioned conductive material on active material layer for example, by the method for sputtering or being vapor-deposited and may be used as collector.

It, can be from active material layer efficiently collected current by providing this conductive layer or metal layer.

As described above, in the laminated body so obtained, positive electrode collector and negative electrode collector preferably have the porosity of 20-60%.Such as the rate of heat addition of the amount by suitably adjusting the conductive material for including in conductive material paste, maximum sintering temperature and/or sintering, it can control the porosity of collector.As described above, maximum sintering temperature and the rate of heat addition of sintering are preferably 700-1000 DEG C.The rate of heat addition of sintering is preferably 400 DEG C/h or higher.

Next, illustrating that each anode active material layer and/or each anode active material layer have the case where collector.

For example, arranging metallic film or conductive material layer as collector using two green sheets, and for example before described two green sheets when providing film collector in anode active material layer.After sintering, two green sheets with collector therebetween are used as an anode active material layer in said combination.In this way, the anode active material layer including the film collector can be obtained.Although having used two green sheets in explanation above, three or more green sheets can be used.

Film collector can be formed in anode active material layer according to mode identical with above-mentioned film collector is formed in anode active material layer.

When using metallic film as collector, as described above, the material of collector can be gold, platinum, palladium, silver, copper, nickel, cobalt or stainless steel.Equally, when using conductive material layer as collector, conductive material can be metal material as described above.

When by dispersing current collector material particle in entire anode active material layer and/or anode active material layer, when collector is provided in the form of three-dimensional network, blended anode current collector material or negative electrode collector material first in the slurry for being used to form anode active material layer and/or the slurry for being used to form anode active material layer.

Using this slurry, positive electrode active materials green sheet or negative electrode active material green sheet are prepared.In gained positive electrode active materials green sheet or negative electrode active material green sheet, collector has three-dimensional net structure.

In the same fashion, the current collector material for including in the slurry can be gold, platinum, palladium, silver, copper, nickel, cobalt or stainless steel.In addition, the amount for the current collector material particle for including in slurry is the every 100 parts by weight of activated preferred 50-300 parts by weight of material.

By using the positive electrode active materials green sheet and negative electrode active material green sheet and film collector or three-dimensional network collector and solid electrolyte green sheet so obtained, the second laminated body is prepared.At this point, it is preferred that exposing one end of anode active material layer and one end of anode active material layer at the different surfaces region of second laminated body.

For example, this exposure at the different surfaces region of second laminated body can be carried out as follows.

During positive electrode active materials green sheet, solid electrolyte green sheet and negative electrode active material green sheet is laminated, one end of positive electrode active materials green sheet and one end of negative electrode active material green sheet are exposed at the different surfaces region of the laminated body.By being sintered this laminated body, one end of anode active material layer and one end of anode active material layer can be exposed at the different surfaces region of second laminated body.

In addition, arranging and/or being laminated according to scheduled pattern each includes positive electrode active materials green sheet, the laminated body of solid electrolyte green sheet and negative electrode active material green sheet.As a result, one end of anode active material layer and one end of anode active material layer can be exposed at the different surfaces region of second laminated body.

In this manner, even in the case where using two layers or more layers anode active material layer and/or anode active material layer, when exposing the collector of each active material layer at the different surfaces region of second laminated body, such as the outer collector for the collector for being connected in parallel each anode active material layer can be readily formed.

Such as, it include the paste with the metal material of electronic conductivity and the glass powder of heat-fusibleization by being applied on the region for exposing positive electrode collector and the region for exposing negative electrode collector, and to its application heat treatment, the outer collector of anode and the outer collector of cathode can be formed.

Additionally, it is preferred that covering the part on second laminated body surface other than the part covered with collector outside collector other than anode and cathode with solid electrolyte layer.For this purpose, the lamination body portion other than the part to be covered by outer collector can be covered with solid electrolyte green sheet for example before sintering laminated body obtains second laminated body.

In addition, also preparing the second laminated body of all solid lithium secondary battery of the present invention as follows.

Prepare first group comprising the combination (step (A)) being made of anode active material layer, anode active material layer and the solid electrolyte layer being inserted between the anode active material layer and anode active material layer.Then, it is sintered described first group at a predetermined temperature to combine anode active material layer, solid electrolyte layer and anode active material layer and crystallize them, to obtain laminated body (step (B)).

In step (A), the first combination can be prepared as follows.

Firstly, positive electrode active materials or negative electrode active material are deposited on scheduled substrate to form the first active material layer.Then, on first active material layer deposition solid electrolyte to form solid electrolyte layer.Then, second active material layer different from first active material layer is deposited on the solid electrolyte layer (i.e. if the first active material layer is anode active material layer, the second active material layer is anode active material layer).In this way, formation includes first group of the combination being made of the first active material layer, solid electrolyte layer and the second active material layer.At this point, first laminated body preferably comprises a kind of combination or two or more combinations of stacking.When including two kinds or more kinds of combinations, these combinations are laminated in the case where being preferably inserted into solid electrolyte layer therebetween.

It can implement the deposition of active material and solid electrolyte by sputtering.

In step (B), preferably 500-900 DEG C at a temperature of heat treatment for solid electrolyte layer and two layers of active material layer crystallize.If the temperature is lower than 500 DEG C, crystallization be may become difficult.

If it is higher than 900 DEG C, the phase counterdiffusion of active material and solid electrolyte may be reinforced.

Furthermore it is possible to which all solid lithium secondary battery of the invention is mounted in sealable metal-back.It in the case, such as can be by being open with sealing plate and washer sealing come sealing metal shell.

Furthermore it is possible to cover all solid lithium secondary battery of the invention with resin.It can apply and resin moulded with resin cover entire battery.

Furthermore, it is possible to which all solid lithium secondary battery surface is made to receive water-proofing treatment.For example, this water-proofing treatment can be implemented by the way that above-mentioned laminated body to be immersed in the dispersion liquid of waterproof material such as silane or fluorocarbon resin.

It can be before with resin covering to the surface applied water-proofing treatment of all solid lithium secondary battery of the invention.

Furthermore it is possible to which the surface to all solid lithium secondary battery of the invention provides glassy layer such as glaze layer.For example, including the slurry of low-melting glass by application and being heat-treated at a predetermined temperature, all solid lithium secondary battery of the invention can be sealed with glassy layer.

As described above, the influence for the moisture for including in atmosphere gas, such as the internal short-circuit due to caused by the reaction between collector metal and water can be eliminated by preventing all solid lithium secondary battery from contacting with atmosphere.

In the preparation method of all solid lithium secondary battery, such as due to the heat treatment (sintering) in air (oxidizing atmosphere), is decomposed by oxidisability and be easy to remove no-bonder and plasticizer.But in the case, only noble metal, such as palladium, gold or platinum may be used as the material of collector.

In the present invention, at least one of negative electrode collector for including in the positive electrode collector and cathode for including in anode can be by relatively inexpensive metal material, such as silver, copper or nickel composition.In the case, second of phosphate cpd of solid electrolyte layer is preferably by Li_1+xM^III _xTi^IV _2-X(PO₄)₃The phosphate cpd of representative, wherein M^IIIIt is to be selected from least one of Al, Y, Ga, In and La metal ion and 0≤x≤0.6, and second of phosphate cpd is preferably used as negative electrode active material.

In the case where using metal material easy to oxidize such as silver, copper or nickel, need to be heat-treated (sintering) in the atmosphere with low oxygen partial pressure.On the other hand, the third phosphate cpd (negative electrode active material), such as FePO₄、Li₃Fe₂(PO₄)₃Or the LiFeP comprising Fe (II1)₂O₇And stable sintering Fe (II1) needs higher partial pressure of oxygen (such as 10^-11Atmosphere (700 DEG C)).That is, the negative electrode active material comprising Fe (II1) cannot be used in some cases when using the metal material of such as silver, copper or nickel as current collector material.In the case, when by using the phosphate cpd such as solid electrolyte without Fe (II1) as negative electrode active material, the collector made of such as metal material of silver, copper or nickel can be used.

But under conditions of this low oxygen partial pressure, the carbonization of binder and plasticizer usually occurs, to interfere the sintering and densification of active material, solid electrolyte and current collector material.In addition, if the carbon generated is conductive, the self-discharge characteristics of gained battery be may deteriorate.Additionally, it is possible to which internal short-circuit occurs.

In addition, when be formed anode active material layer by general formula LiMPO₄When the first phosphate cpd represented includes at least Fe, sintering causes to generate such as Li in anode active material layer in the oxidizing atmosphere of such as air₃Fe₂(PO₄)₃Fe (III) compound, so that the charging/discharging capacity of battery and internal resistance can increase.If in such as Ar or N₂Non-oxidizing atmosphere in be sintered to prevent Fe (III), the carbonization of above-mentioned binder and plasticizer occurs, this can generate various detrimental effects to battery.

When collector is made of such as metal material of copper, silver or nickel, it is sintered in the atmosphere gas of the gas comprising steam and with low oxygen partial pressure preferred to avoiding being carbonized.In this atmosphere, because promoting the thermal decomposition of organic substance, it is possible to except no-bonder and plasticizer inhibit the generation of carbon simultaneously.As a result, positive electrode active materials, negative electrode active material and solid electrolyte can be densely sintered.Therefore, the charge/discharge characteristics and reliability of battery can be improved.

In addition, can remove binder and plasticizer when positive electrode active materials include Fe while inhibiting the generation of Fe (III) and the generation of carbon.

Illustrate an example of the preparation method of all solid lithium secondary battery below.In the preparation method, positive electrode active materials green sheet is prepared using slurry 1, and prepare solid electrolyte green sheet using slurry 2.Then, formation includes the second green sheet group of at least one combination being made of the positive electrode active materials green sheet and solid electrolyte green sheet.Then, the second green sheet group is heat-treated to obtain the laminated body of at least one entire combination including anode active material layer and solid electrolyte layer.In preparing the second green sheet group, the combination is prepared by using at least two panels positive electrode active materials green sheet and at least two panels solid electrolyte green sheet.It is inserted into positive electrode collector between at least two panels positive electrode active materials green sheet, while being inserted into negative electrode collector between at least two panels solid electrolyte green sheet.Solid electrolyte is used as negative electrode active material, and at least one positive electrode collector and negative electrode collector are selected from silver, copper and mickel.In addition, being heat-treated in the atmosphere gas of the gas comprising steam and with low oxygen partial pressure.

In addition, when using the LiMPO including at least Fe₄(such as LiFePO₄) when being used as positive electrode active materials, the oxidation number for the Fe for including in positive electrode active materials is divalent.It is preferred that being sintered in divalent Fe stable condition.Therefore, it is sintered oxygen balance contained in (heat treatment) atmosphere and divides PO₂It is preferred that in the range of being represented by following formula (1):

-0.0310T+3.5≤-log₁₀PO₂≤-0.0300T+38.1。

If partial pressure of oxygen is greater than the range represented by formula (1), Fe may be oxidized or collector may be oxidized.On the other hand, if partial pressure of oxygen is less than the range represented by formula (1), inhibit the generation of carbon that may become difficult.

In addition, sintering atmosphere preferably comprises at least the mixed gas containing the gas that can discharge oxygen and the gas reacted with oxygen in order to stably keep partial pressure of oxygen within the above range.One example of this mixed gas is the mixed gas comprising carbon dioxide gas, hydrogen and nitrogen.It is, for example, possible to use carbon dioxide gas as can discharge the gas of oxygen, and hydrogen can be used as the gas reacted with oxygen.When mixed gas includes hydrogen, in order to which the volume of safety hydrogen wherein included is preferably no greater than 4%, that is, it is lower than the hydrogen explosion limit.

When using the gas by this gas composition, since balanced reaction can steadily maintain the partial pressure of oxygen of sintering atmosphere constant therebetween in sintering (heat treatment).

In the preparation of first laminated body, when active material includes Fe etc., the partial pressure of oxygen of atmosphere gas is further preferably adjusted.

In addition, in the case where sintering includes the laminated body of the collector made of such as metal material of silver, copper, nickel or cobalt, or in the case where sintering includes the laminated body of the active material containing Fe etc., atmosphere gas preferably has less than this material oxidation-reduction equilibrium oxygen partial pres-sure partial pressure of oxygen.This atmosphere gas can be comprising carbon dioxide gas (CO₂) and hydrogen (H₂) mixed gas.When use includes CO₂And H₂Mixed gas when, it is low for can maintaining the partial pressure of oxygen of mixed gas.

According to the metal material of collector, change the CO for including in mixed gas as one sees fit₂And H₂Mixed proportion.For example, CO in mixed gas₂And H₂Between volume ratio be preferably 10-8 × 10³:1.If the volume ratio of carbon dioxide gas and hydrogen less than 10, is decomposed binder and be may become difficult.If the volume ratio of carbon dioxide gas and hydrogen is greater than 8 × 10³, collector may be oxidized.

When collector is made of copper, CO in atmosphere gas₂And H₂Between volume ratio such as can be 10³∶1。

When collector is made of cobalt, CO in atmosphere gas₂And H₂Between volume ratio such as can be 10: 1.

When collector is made of nickel, CO in atmosphere gas₂And H₂Between volume ratio such as can be 40: 1.When collector is made of nickel, CO₂And H₂Between volume ratio be preferably 10-50: 1.

The hydrogen volume for including in mixed gas is preferably 4% or lower.Reason is same as described above.

As described above, for example when anode active material layer includes by general formula LiMPO₄When the first phosphate cpd and the first described phosphate cpd represented includes at least Fe, further preferably use comprising CO₂And H₂Mixed gas as roasting atmosphere gas.CO₂And H₂Between volume ratio be preferably 10-10⁴:1.If the ratio of carbon dioxide gas and hydrogen less than 10, is decomposed binder and be may become difficult.If the volume ratio of carbon dioxide gas and hydrogen is greater than 10^’4, positive electrode active materials may decompose.

Embodiment

Embodiment 1-1

When as described above, when generating the first laminated body or the second laminated body between active material and solid electrolyte with electro-chemical activity interface using sintering method, the side reaction other than needing not being sintered at the sintered interface during sintering between active material and solid electrolyte.Therefore, reactivity when heating at 800 DEG C between active material and solid electrolyte is checked.

Firstly, illustrating the reactivity between positive electrode active materials and solid electrolyte.

(sintered body 1)

Use LiCoPO₄As positive electrode active materials, and use Li_1.3Al_0.3Ti_1.7(PO₄)₃As solid electrolyte.Positive electrode active materials and solid electrolyte are crushed in ball milling respectively, about 1 μm of partial size is made.These powder are mixed in ball milling with 1: 1 weight ratio and the particle of diameter 18mm is shaped by powder compacting.It is sintered particle 5 hours at 800 DEG C.Sintered body is crushed with agate mortar.Broken sintered body is referred to as sintered body 1.

(sintered body 2)

In addition to using LiNiPO₄Outside as positive electrode active materials, sintered body 2 is prepared according to mode identical with sintered body 1.

(comparing sintered body 1)

In addition to using LiCoO₂Outside as positive electrode active materials, according to being prepared with the identical mode of sintered body 1 compared with sintered body 1.

(comparing sintered body 2)

In addition to using LiMn₂O₄Outside as positive electrode active materials, according to being prepared with the identical mode of sintered body 1 compared with sintered body 2.

(comparing sintered body 3)

In addition to using Li_0.33La_0.56TiO₃Outside as solid electrolyte, according to being prepared with the identical mode of sintered body 1 compared with sintered body 3.

(comparing sintered body 4)

In addition to using LiNiPO₄As positive electrode active materials and use Li_0.33La_0.56TiO₃Outside as solid electrolyte, according to being prepared with the identical mode of sintered body 1 compared with sintered body 4.

(comparing sintered body 5)

In addition to using LiCoO₂As positive electrode active materials and use Li_0.33La_0.56TiO₃Outside as solid electrolyte, according to being prepared with the identical mode of sintered body 1 compared with sintered body 5.

(comparing sintered body 6)

In addition to using LiMn₂O₄As positive electrode active materials and use Li_0.33La_0.56TiO₃Outside as solid electrolyte, according to being prepared with the identical mode of sintered body 1 compared with sintered body 6.

(sintered body 3)

In addition to using LiCo_0.5Ni_0.5PO₄Outside as positive electrode active materials, sintered body 3 is prepared according to mode identical with sintered body 1.

Using sintered body 1-3 and compare sintered body 1-6, the x-ray diffraction pattern after checking them before sintering by using the Alpha-ray X-ray diffraction analysis of Cu K.The x-ray diffraction pattern of various sintered bodies is shown in Fig. 1-9.In Fig. 1-9, sintered x-ray diffraction pattern is represented by A, and the x-ray diffraction pattern before sintering is represented by B.

It is well maintained with the position at peak each after heat treatment and pattern before heat treatment in Fig. 1 (sintered body 1), Fig. 2 (sintered body 2) and Fig. 9 (sintered body 3).On the other hand, in Fig. 3-8 (comparing sintered body 1-6), occurs new peak after heat treatment.

Result above clearly illustrates in sintered body 1-3, the third phase generated due to solid phase reaction will not occur at sintered interface between positive electrode active materials and solid electrolyte, but in relatively sintered body 1-6, occur not being the third phase that positive electrode active materials are also not solid electrolyte.

Therefore, when using the first described phosphate cpd (positive electrode active materials) and second of phosphate cpd (solid electrolyte) to prepare laminated body, by being sintered, can be bonded together positive electrode active materials and solid electrolyte without the interface generation between positive electrode active materials and solid electrolyte be not third phase that positive electrode active materials are also not solid electrolyte.

Next, illustrating the reactivity between negative electrode active material and solid electrolyte.

(sintered body 4)

Use the FePO of tripartite₄As negative electrode active material, and use Li_1.3Al_0.3Ti_1.7(PO₄)₃As solid electrolyte.Negative electrode active material and solid electrolyte are crushed in ball milling respectively, about 1 μm of partial size is made.These powder are mixed in ball milling with 1: 1 weight ratio and the particle of diameter 18mm is shaped by powder compacting.Particle is sintered 5 hours at 800 DEG C in air.Sintered body is crushed with agate mortar.Broken sintered body is referred to as sintered body 4.

(sintered body 5)

In addition to using Li₃Fe₂(PO₄)₃Outside as negative electrode active material, sintered body 5 is prepared according to mode identical with sintered body 4.

(sintered body 6)

In addition to using LiFeP₂O₇Outside as negative electrode active material, sintered body 6 is prepared according to mode identical with sintered body 4.

(comparing sintered body 7)

In addition to using Li₄Ti₅O₁₂Outside as negative electrode active material, according to being prepared with the identical mode of sintered body 4 compared with sintered body 7.

(comparing sintered body 8)

In addition to using Nb₂O₅Outside as negative electrode active material, according to being prepared with the identical mode of sintered body 4 compared with sintered body 8.

(comparing sintered body 9)

In addition to using Li_0.33La_0.56TiO₃Outside as solid electrolyte, according to being prepared with the identical mode of sintered body 4 compared with sintered body 9.

(comparing sintered body 10)

In addition to using tripartite Li₃Fe₂(PO₄)₃As negative electrode active material and use Li_0.33La_0.56TiO₃Outside as solid electrolyte, according to being prepared with the identical mode of sintered body 4 compared with sintered body 10.

(comparing sintered body 11)

In addition to using LiFeP₂O₇As negative electrode active material and use Li_0.33La_0.56TiO₃Outside as solid electrolyte, according to being prepared with the identical mode of sintered body 4 compared with sintered body 11.

(sintered body 12)

In addition to using Li₄Ti₅O₁₂As negative electrode active material and use Li_0.33La_0.56TiO₃Outside as solid electrolyte, according to being prepared with the identical mode of sintered body 4 compared with sintered body 12.

(comparing sintered body 13)

In addition to using Nb₂O₅As negative electrode active material and use Li_0.33La_0.56TiO₃Outside as solid electrolyte, according to being prepared with the identical mode of sintered body 4 compared with sintered body 13.

According to method same as above, using sintered body 4-6 and 12 and compare sintered body 7-11 and 13, the x-ray diffraction pattern after checking them before sintering.The x-ray diffraction pattern of various sintered bodies is shown in Figure 10-19.In figs. 10-19, sintered x-ray diffraction pattern is represented by A, and represents the x-ray diffraction pattern before sintering by B.

It is well maintained with the position at peak each after heat treatment and pattern before heat treatment in Figure 10 (sintered body 4), Figure 11 (sintered body 5), Figure 12 (sintered body 6) and Figure 18 (sintered body 12).On the other hand, in Figure 13-17 (comparing sintered body 7-11) and Figure 19 (comparing sintered body 13), due to heat treatment, there is peak intensity and be substantially reduced or new peak.This is clearly illustrated in sintered body 4-6 and sintered body 12, the third phase generated due to solid phase reaction will not occur at sintered interface between negative electrode active material and solid electrolyte, but relatively sintered body 7-11 and comparing in sintered body 13, occur not being the third phase that negative electrode active material is also not solid electrolyte.

Therefore, as use second of phosphate cpd (solid electrolyte) and the third described phosphate cpd (negative electrode active material) and use such as Li containing titanyl compound₄Ti₅O₁₂(negative electrode active material) and such as Li containing titanyl compound_0.33La_0.56TiO₃When (solid electrolyte), negative electrode active material and solid electrolyte can be bonded together to form laminated body by sintering, not be the third phase that negative electrode active material is also not solid electrolyte without the interface generation between negative electrode active material and solid electrolyte.

Therefore, sintered body 1-3's the result shows that anode active material layer comprising the first phosphorus-containing compound and the solid electrolyte layer comprising second of phosphate cpd can be bonded together, does not have contributive impurity phase to the charge/discharge of battery without generating in the interface of anode active material layer and solid electrolyte interlayer.In addition, sintered body 4-6's and 12, the result shows that the solid electrolyte layer comprising second phosphate cpd and the anode active material layer comprising the third phosphate cpd and the solid electrolyte layer comprising titanium-containing oxide and the anode active material layer comprising titanium-containing oxide can be bonded together, does not have contributive impurity phase to the charge/discharge of battery without generating in the interface of anode active material layer and solid electrolyte interlayer.

Embodiment 1-2

Following battery and comparative cell are prepared, and is charged and discharged under predetermined circumstances, to obtain their discharge capacity.

(battery 1)

Firstly, preparation is by Li_1.3Al_0.3Ti_1.7(PO₄)₃The solid electrolyte powder of representative and by LiCoPO₄The positive electrode active material powder of representative.Mix solid electrolyte powder with polyvinyl butyral resin, the n-butyl acetate as solvent and the dibutyl phthalate as plasticizer for being used as binder, and mixture is mixed together 24 hours with zirconia balls in ball milling, prepares the slurry for being used to form solid electrolyte layer.

The slurry for being used to form anode active material layer is prepared according further to mode identical with solid electrolyte layer slurry.

Then, solid electrolyte layer slurry is administered on the film carrier 1 being mainly made of polyester resin using scraper.Then, the slurry of dry application, obtains solid electrolyte green sheet 2 as shown in Figure 20 (thickness: 25 μm).It should be understood that the surface of film carrier 1 has the releasing agent layer being mainly made of Si.

In addition, preparing identical mode according to solid electrolyte green sheet, positive electrode active materials green sheet 4 (thickness: 4 μm) is formed on film carrier 3 as shown in Figure 21.

Then, the polyester film 6 of adhesive is fixed on carrier 5 two sides application.Then, as shown in Figure 22, the face for the solid electrolyte green sheet not contacted with film carrier 1 is placed on polyester film 6.

Then, applying 80kg/cm from upper direction film carrier 1²Pressure and 70 DEG C of heating under, remove film carrier from film carrier 1 and solid electrolyte green sheet 2, as shown in Figure 23.

The solid electrolyte green sheet 2 ' prepared on another film carrier 1 ' in same manner described above is placed in solid electrolyte green sheet 2.Then, by applying pressure and heating from upper direction film carrier 1 ', green sheet 2 and 2 ' is bonded together and removing film carrier 1 ' from green sheet 2 '.

By repeating this operation 20 times, solid electrolyte green sheet group 7 (thickness: 500 μm) is produced.

Then, the positive electrode active materials green sheet 4 formed on film carrier 3 in the manner described above is placed in the green sheet group 7 so obtained.Then, by applying 80kg/cm from upper direction film carrier 3²Pressure and 70 DEG C of heating, from green sheet 4 remove film carrier 3.In this way, as shown in Figure 24, preparing the laminated body (thickness: about 500 μm) of green sheet group 7 and positive electrode active materials green sheet 4.This laminated body is removed from polyester film 6 and is cut into the size of 7mm (width) × 7mm (length) × about 500 μm (thickness), obtains green part 8.

Then, as shown in Figure 25, the green part 8 that two panels so obtains is combined.At this point, the solid electrolyte face 9 of green part 8 is in contact with each other, the green part 8 be located at positive electrode active materials green sheet 4 back on side, so that active material green sheet 4 is outside.

Then, make them fully absorb Li to prepare two panels ceramic wafer 10 by roasting in Li atmosphere.A pair of of green sheet is clipped between ceramic wafer 10, so that they are contacted with active material green sheet 4.

During sintering because Li be it is volatile, Li may volatilize from green sheet.The ceramic wafer that Li has been fully absorbed by using these is inhibited Li to volatilize from green sheet therebetween and inhibits the formation of impurity layer in sintering.

Then, they are heated to 400 DEG C with the rate of heat addition of 400 DEG C/h in air and are maintained 5 hours at 400 DEG C, so that organic substance such as binder and plasticizer are sufficiently decomposed due to heat.Then, they are heated to 900 DEG C with the rate of heat addition of 400 DEG C/h and room temperature is rapidly cooled to the cooling velocity of 400 DEG C/h.In this way, sintering green part.

The filling rate of the green part of sintering can for example determine as follows.

Firstly, the weight for the active material layer for including in the weight and active material layer of the solid electrolyte for including in acquisition solid electrolyte layer.Specifically, for example determining Co content that the active material green sheet of Ti content or per unit area predetermined thickness that the solid electrolyte layer green sheet of per unit area predetermined thickness includes includes by icp analysis.From resulting Ti and Co content, the Li of per unit area solid electrolyte layer green sheet can be determined_1.3Al_0.3Ti_1.7(PO₄)₃The LiCoPO of weight and active material green sheet₄Weight.

Then, the solid electrolyte layer of the green part (chip) of sintering and the volume of active material layer are obtained.Because the green part of sintering is prism-shaped (prismatic), such as shown in figure 24, it is possible to determine every layer of volume from the area of their bottoms and every layer of thickness.By multiple sections with the measurements such as scanning electron microscope (SEM) such as green part, such as scheduled five sections, and average value is obtained as every layer of thickness, can obtain every layer of thickness.

The volume of the weight for the active material for including from active material layer and such resulting active material layer, can obtain the apparent density ((weight for the active material for including in active material layer)/(volume of the active material layer of sintering)) of active material layer.This is applied equally to solid electrolyte layer.

As described above, filling rate is the ratio of the apparent density of active material layer and the real density of active material in the case where active material layer, it is expressed as a percentage.Therefore, when using real density of the X-ray density of active material as active material, filling rate can be obtained from following formula:

{ [(weight for the active material for including in active material layer)/(volume of the active material layer of sintering)]/(the X-ray density of active material) } × 100.

Furthermore it is possible to obtain the filling rate of solid electrolyte layer according to method same as above.

Further, it is also possible to make in the following method.By with active material layer and solid electrolyte layer is prepared separately in active material layer of the sintering comprising predetermined amount active material and the solid electrolyte layer comprising predetermined amount solid electrolyte under identical sintering condition in preparation laminated body.Every layer of filling rate so obtaining is determined from the equations above, and uses resulting value as every layer of laminated body of filling rate.

In the present embodiment, because active material layer is compared with solid electrolyte layer be it is sufficiently thin, it is assumed that sintering green part only by Li_1.3Al_0.3Ti_1.7(PO₄)₃Its filling rate is determined in the case where composition.As a result, filling rate is about 83%.The following filling rate for determining green part: [{ (green part weight)/(green part volume) }/(the X-ray density of solid electrolyte)] × 100.

The filling rate of active material can be speculated for almost 100% from such as SEM image.

In addition, checking anode active material layer with the polishing section of the green part of SEM observation sintering.Observation confirms that anode active material layer is densely sintered with about 1 μm of thickness and anode active material layer, almost without hole.

It should be understood that two panels green part is not bonded together by sintering although being sintered a pair of of green part.

Then, by green part into two pieces.As shown in Figure 26, first laminated body 11 is made of anode active material layer 11a and solid electrolyte layer 11b, and sputters gold on the surface anode active material layer 11a to form gold thin film 12 (thickness: a few nanometers to tens of nanometers) as positive electrode collector.It is polished with sand paper and removes the gold being adhered on each side 13 of the first laminated body 11.

It then, in dew point is as follows that anti-reduction electrolyte layer and anode active material layer are formed in the first laminated body in -50 DEG C or lower dry air.

Firstly, by the lithium metal foil 14 of 150 μ m-thicks strike out 10mm diameter and be fixed to struck out 0.5mm thickness and 20mm diameter SUS plate 15 center portion.SUS plate is used as negative electrode collector.

The polyethylene glycol oxide (hereinafter referred to as PEO) and LiN (SO of average molecular weight 1,000,000 are dissolved in anhydrous acetonitrile₂CF₃)₂(hereinafter referred to as LiTFSI), so that the oxygen atom of PEO and the lithium of LiTFSI meet relationship: [O]/[Li]=20/1.The solution is adjusted, so that Li concentration is 0.1M.

Then, the solution is spun in lithium metal and is dried in vacuo at 2000rpm, form PEO-LiTFSI layer 16 on lithium metal foil 14.After vacuum drying, PEO-LiTFSI layers of thickness is checked with SEM and be about 50 μm.

The PEO-LiTFSI layer 16 is bonded to positioned at anode active material layer back on the solid electrolyte face 17 of the first laminated body 11 on side.In this way, preparing all solid lithium secondary battery as shown in Figure 27.The battery is referred to as battery 1.

(battery 2)

In addition to using LiMnPO₄Instead of LiCoPO₄Outside, battery 2 is prepared according to mode identical with battery 1.

(comparative cell 1)

In addition to using LiCoO₂Instead of LiCoPO₄Outside, comparative cell 1 is prepared according to mode identical with battery 1.

(comparative cell 2)

In addition to using LiMn₂O₄Instead of LiCoPO₄Outside, comparative cell 2 is prepared according to mode identical with battery 1.

(battery 3)

With reference to Figure 28, illustrate to prepare all solid lithium secondary battery using sputtering.

0.05 μ m-thick titanium film 23 is formed in 30mm × 30mm monocrystalline substrate 22 that surface is covered with silicon nitride layer 21 by RF magnetron sputtering.In addition, forming 0.5 μ m-thick gold thin film 24 in titanium film 23 as positive electrode collector.At this point, the metal mask being open using 20mm × 12mm.Titanium film 23 has the function of for silicon nitride layer 21 and gold thin film 24 being bonded together.

Then, using LiCoPO₄Target forms 0.5 μ m-thick LiCoPO by RF magnetron sputtering in gold thin film 24₄Film 25.At this point, the metal mask being open using 10mm × 10mm.In addition, using the sputter gas being made of 25% oxygen and 75% argon gas.

Then, the metal mask of arrangement 15mm × 15mm opening, so that LiCoPO₄Film 25 is placed in the center of the opening.Use LiTi₂(PO₄)₃Target forms 2 μ m-thick LiTi by RF magnetron sputtering₂(PO₄)₃ Film 26 covers LiCoPO₄Film 25.Use the sputter gas being made of 25% oxygen and 75% argon gas.

Gained laminated body is set to anneal 2 hours at 600 DEG C in air, to make LiCoPO₄Positive electrode active materials and LiTi₂(PO₄)₃Solid electrolyte crystallization.In this way, forming the first laminated body.

Then, in the LiTi for being used as solid electrolyte layer₂(PO₄)₃Anti- reduction electrolyte layer and the lithium metal layer as cathode are formed on film 26.It is to form these layers in -50 DEG C or lower dry air in dew point.

Specifically, firstly, PEO (average molecular weight 1,000,000) and LiTFSI are dissolved in anhydrous acetonitrile, so that the oxygen atom of PEO and the lithium of LiTFSI meet relationship: [O]/[Li]=20/1.The solution has the Li concentration of 0.05M.

Then, the solution is spun to LiTi at 2000rpm₂(PO₄)₃It on film 26 and is dried in vacuo, forms the PEO-LiTFSI layer 27 for being used as anti-reduction electrolyte layer.After vacuum drying, PEO-LiTFSI layers of thickness is measured, with SEM with a thickness of about 5 μm.

Then, by the heat-resisting lithium metal film 28 for forming 0.5 μ m-thick on PEO-LiTFSI layer 27 that is deposited on as cathode.At this point, the metal mask being open using 10mm × 10mm.

Then, negative electrode collector is used as by the Copper thin film 29 that RF magnetron sputtering forms 0.5 μ m-thick, so that lithium metal film 28 be completely covered in the case where not contacting with the gold thin film 24 for being used as positive electrode collector.In this way, obtaining all solid lithium secondary battery as shown in Figure 28.At this point, the metal mask being open using 20mm × 12mm.

Thus obtained all solid lithium secondary battery is referred to as battery 3.Anode layer and each filling rate of solid electrolyte layer are about 100%.

(battery 4)

In addition to using LiMnPO₄Instead of LiCoPO₄Outside, battery 4 is prepared according to mode identical with battery 3.

(comparative cell 3)

In addition to using LiCoO₂Instead of LiCoPO₄Outside, comparative cell 3 is prepared according to mode identical with battery 3.

(comparative cell 4)

In addition to using LiMn₂O₄Instead of LiCoPO₄Outside, comparative cell 4 is prepared according to mode identical with battery 3.

It is that it is primary that these batteries are charged and discharged with the current value of 10 μ A in -50 DEG C of atmosphere and 60 DEG C of environment temperature in dew point just after just preparing battery 1-4 and comparative cell 1-4.Gained discharge capacity is expressed as initial discharge capacity.In addition, upper blanking voltage and lower blanking voltage has been displayed in Table 1.

Table 1

	Initial discharge capacity (μ Ah)	Upper blanking voltage (V)	Lower blanking voltage (V)
	Initial discharge capacity (μ Ah)	Upper blanking voltage (V)	Lower blanking voltage (V)	Battery 1	10.3	5	3.5
Battery 2	19.3	4.6	3.3	Battery 1	10.3	5	3.5
Battery 2	19.3	4.6	3.3	Comparative cell 1	0	4.2	3.0
Comparative cell 2	0	4.5	3.5	Comparative cell 1	0	4.2	3.0
Comparative cell 2	0	4.5	3.5	Battery 3	13.7	5	3.5
Battery 4	11.9	4.6	3.3	Battery 3	13.7	5	3.5
Battery 4	11.9	4.6	3.3	Comparative cell 3	0	4.2	3.0
Comparative cell 4	0	4.5	3.5	Comparative cell 3	0	4.2	3.0

As shown in table 1, comparative cell 1-4 cannot discharge.This may be because being formed due to being heat-treated interface between positive electrode active materials and solid electrolyte neither positive electrode active materials are also not the impurity phase of solid electrolyte and interface becomes electrochemical deactivation.

On the other hand, battery 1-4 can be charged and discharged.This may be because in the present invention, it is not formed to react charge/discharge with the interface between the solid electrolyte comprising second of phosphate cpd of crystalline form with lithium-ion-conducting in the positive electrode active materials comprising capableing of the crystalline form of absorption and desorption lithium ion the first phosphate cpd and does not have contributive impurity phase, and interface is electro-chemical activity.

As discussed above, it has been shown that according to the present invention, because the interface between positive electrode active materials and solid electrolyte not will form impurity phase, interface is electro-chemical activity and charge/discharge is possible.

Then, in order to obtain charge/discharge cycle circle number when discharge capacity becomes initial discharge capacity 60%, it is so that battery 1-4 is received recharge and discharge cycles with the current value of 10 μ A in the range of 3.5-5.0V in -50 DEG C of atmosphere and 60 DEG C of environment temperature in dew point.Table 2 shows result.

Table 2

	Discharge capacity becomes the charge/discharge cycle circle number (circle number) when initial discharge capacity 60%
		Battery 1	103
Battery 2	97	Battery 1	103
Battery 2	97	Battery 3	182
Battery 4	179	Battery 3	182

Battery 1 and 2 can charge/discharge cycle about 100 enclose, and battery 3 and 4 can charge/discharge cycle about 180 enclose.

In addition, using by 70 parts by weight LiCoPO₄, 25 parts by weight acetylene blacks and 5 parts by weight polytetrafluoroethylene (PTFE) composition anode, the cathode made of lithium metal, pass through ethylene carbonate (EC) and dimethyl carbonate (DMC) solvent mixture (EC: DMC=1: 1 (volume ratio)) in dissolution 1M LiPF₄The electrolyte of preparation prepares traditional liquid type batteries.Its cycle life is measured in same manner described above, and is about 10 circles.

As described above, the cycle life of battery more of the present invention and the cycle life of traditional liquid type battery show that the cycle life of battery of the present invention significantly improves.

Embodiment 1-3

Then, the filling rate of laminated body is checked.

(battery 5)

It is outer except through being sintered in the heating rate of 400 DEG C/h to 850 DEG C, battery 1 is prepared according to mode identical with battery 1.

(reference battery 6)

It is outer except through being sintered in the heating rate of 400 DEG C/h to 800 DEG C, reference battery 6 is prepared according to mode identical with battery 1.

The impedance of battery 1, battery 5 and reference battery 6 is detected at 1 khz.

Table 3 shows the impedance of the filling rate and these batteries of the laminated body used in battery 1, battery 5 and reference battery 6.As for filling rate, according to identical mode in embodiment 1-2 it is assumed that laminated body only by Li_1.3Al_0.3Ti_1.7(PO₄)₃Filling rate as shown in table 3 is obtained in the case where composition.

Table 3

	Filling rate (%)	Impedance (Ω)
	Filling rate (%)	Impedance (Ω)	Battery 1	83	3010
Battery 5	72	3520	Battery 1	83	3010
Battery 5	72	3520	Reference battery 6	55	144000

As shown in table 3, when the filling rate of laminated body is less than 70%, impedance increases sharply.This may be because positive electrode active material powder and the insufficient sintering of solid electrolyte powder lead to the reduction of lithium ion conduction path sizes.

In addition, the battery with big impedance is undesirable because battery meets with the deterioration of high magnification charge/discharge capabilities.

Above the result shows that forming the anode active material layer of laminated body and solid electrolyte layer and each filling rate of anode active material layer are preferably both greater than 70%.

Embodiment 1-4

Preparation includes the battery of combined anode active material layer, solid electrolyte layer and anode active material layer.

(battery 7)

Firstly, preparation is by Li_1.3Al_0.3Ti_1.7(PO₄)₃The solid electrolyte powder of representative, by LiCoPO₄The positive electrode active material powder of representative and by Li₃Fe₂(PO₄)₃The negative electrode active material powder of representative.

By mixing solid electrolyte powder with polyvinyl butyral resin, the n-butyl acetate as solvent and the dibutyl phthalate as plasticizer for being used as binder, and mixture is mixed together 24 hours with zirconia balls in ball milling, prepares the slurry for being used to form solid electrolyte layer.

The slurry for being used to form anode active material layer and the slurry for being used to form anode active material layer are prepared according further to mode identical with solid electrolyte layer slurry.

Then, solid electrolyte layer slurry is administered on the film carrier 30 being mainly made of polyester resin using scraper.Then, the slurry of dry application, obtains solid electrolyte green sheet 31 as shown in Figure 29 (thickness: 25 μm).The surface of film carrier 30 has the releasing agent layer being mainly made of Si.

As shown in Figure 30, according to method identical with solid electrolyte green sheet, positive electrode active materials green sheet 32 (thickness: 4 μm) is formed on another film carrier 30.Equally, as shown in Figure 31, negative electrode active material green sheet 33 (thickness: 7 μm) is formed on another film carrier 30.

Then, the polyester film 35 of adhesive is fixed on carrier 34 two sides application.Then, as shown in Figure 32, the face of negative electrode active material green sheet 33 not contacted with film carrier 30 is placed on polyester film 35.

Then, applying 80kg/cm from upper direction film carrier 30²Pressure and 70 DEG C of heating under, from negative electrode active material green sheet 33 remove film carrier 30, as shown in Figure 33.

Then, the face of solid electrolyte green sheet 31 not contacted with film carrier is placed in negative electrode active material green sheet 33.Under the conditions of pressure and temperature same as described above, solid electrolyte green sheet is bonded in negative electrode active material green sheet and removes film carrier from solid electrolyte green sheet.

The solid electrolyte green sheet 31 ' prepared on another film carrier 30 ' in same manner described above is placed in solid electrolyte green sheet 31.Then, by applying pressure and heating from upper direction film carrier 30 ', green sheet 31 and 31 ' is bonded together and removing film carrier 30 ' from green sheet 31 '.

By repeating this operation 20 times, solid electrolyte green sheet group 36 (thickness: 500 μm) is produced.

Then, the positive electrode active materials green sheet 32 formed on film carrier 30 in the manner described above is placed in the solid electrolyte green sheet group 36 so obtained.Then, by applying 80kg/cm from upper direction film carrier 30²Pressure and 70 DEG C of heating, from positive electrode active materials green sheet 32 remove film carrier 30.In this way, as shown in Figure 34, preparing the laminated body (thickness: about 500 μm) of negative electrode active material green sheet 33, solid electrolyte green sheet group 36 and positive electrode active materials green sheet 32.This laminated body is removed from polyester film 35 and is cut into the size of 7mm (width) × 7mm (length) × about 500 μm (thickness), obtains green part (the first green sheet group) 37.

Then, as shown in Figure 35, the green part 37 that two panels so obtains is combined, so that the negative electrode active material green sheet 33 of green part 37 is in contact with each other, and positive electrode active materials green sheet 32 is outside.

Then, make them fully absorb Li to prepare two panels ceramic wafer 38 by roasting in Li atmosphere.A pair of of green sheet is clipped between ceramic wafer, so that they are contacted with positive electrode active materials green sheet 32.

According to the filling rate for the green part for determining sintering with mode identical in embodiment 1-2.As a result, the filling rate of the green part of sintering is about 83%.

In addition, checking anode active material layer and anode active material layer with the polishing section of the green part of SEM observation sintering.Observation confirm anode active material layer with about 1 μm thickness, anode active material layer have about 2 μm thickness and anode active material layer and anode active material layer be densely sintered, almost without hole.

Then, by green part into two pieces, acquisition includes by the second laminated body 39 of anode active material layer 39a, solid electrolyte layer 39b and anode active material layer the 39c combination formed, as shown in Figure 36.Gold is sputtered on the surface anode active material layer 39a of the second laminated body 39 to form gold thin film 40 (thickness: a few nanometers to tens of nanometers) as positive electrode collector.Equally, gold is sputtered on the surface anode active material layer 39c of laminated body 39 to form gold thin film 41 (thickness: a few nanometers to tens of nanometers) as negative electrode collector.Then, it is polished with sand paper and removes the gold being adhered on each side 42 of prismatic laminated body 39.In this way, preparing all solid lithium secondary battery.The battery is referred to as battery 7.

(battery 8)

In addition to using LiMnPO₄LiCoPO is replaced as positive electrode active materials₄Outside, battery 8 is prepared according to mode identical with battery 7.It is assumed that green part only by Li_1.3Al_0.3Ti_1.7(PO₄)₃In the case where composition, the filling rate of the green part of sintering is 80%.

(battery 9)

In addition to using FePO₄Li is replaced as negative electrode active material₃Fe₂(PO₄)₃Outside, battery 9 is prepared according to mode identical with battery 7.It is assumed that green part only by Li_1.3Al_0.3Ti_1.7(PO₄)₃In the case where composition, the filling rate of the green part of sintering is 85%.

(battery 10)

In addition to using LiFeP₂O₇Li is replaced as negative electrode active material₃Fe₂(PO₄)₃Outside, battery 10 is prepared according to mode identical with battery 7.It is assumed that green part only by Li_1.3Al_0.3Ti_1.7(PO₄)₃In the case where composition, the filling rate of the green part of sintering is 75%.

(comparative cell 5)

In addition to using LiCoO₂LiCoPO is replaced as positive electrode active materials₄And use Li₄Ti₅O₁₂Instead of Li₃Fe₂(PO₄)₃Outside, comparative cell 5 is prepared according to mode identical with battery 7.It is assumed that green part only by Li_1.3Al_0.3Ti_1.7(PO₄)₃In the case where composition, the filling rate of the green part of sintering is 71%.

(battery 11)

All solid lithium secondary battery as shown in figure 37 is prepared as follows using sputtering.

0.05 μ m-thick titanium film 45 is formed in 30mm × 30mm monocrystalline substrate 44 that surface is covered with silicon nitride layer 43 by RF magnetron sputtering.In addition, forming 0.5 μ m-thick gold thin film 46 in titanium film 45 as positive electrode collector.At this point, the metal mask being open using 20mm × 12mm.Titanium film 45 has the function of for silicon nitride layer 43 and gold thin film 46 being bonded together.

Then, using LiCoPO₄Target forms 0.5 μ m-thick LiCoPO by RF magnetron sputtering in gold thin film 46₄Film 47.At this point, the metal mask being open using 10mm × 10mm, and use the sputter gas being made of 25% oxygen and 75% argon gas.

Then, the metal mask of arrangement 15mm × 15mm opening, so that LiCoPO₄Film 47 is placed in the center of the opening.Use LiTi₂(PO₄)₃Target forms 2 μ m-thick LiTi by RF magnetron sputtering₂(PO₄)₃ Film 48 covers LiCoPO₄Film 47.The sputter gas being made of 25% oxygen and 75% argon gas is used in sputtering.

Then, using Li₃Fe₂(PO₄)₃Target is by RF magnetron sputtering in LiTi₂(PO₄)₃1 μ m-thick Li is formed on film 48₃Fe₂(PO₄)₃Film 49.At this point, the metal mask being open using 10mm × 10mm, and use the sputter gas being made of 25% oxygen and 75% argon gas.

Gained laminated body (first group) is set to anneal 2 hours at 600 DEG C, thus in conjunction with LiCoPO₄Anode active material layer, LiTi₂(PO₄)₃Solid electrolyte and Li₃Fe₂(PO₄)₃Anode active material layer and make they crystallize.

Then, negative electrode collector is used as by the Copper thin film 50 that RF magnetron sputtering forms 0.5 μ m-thick, so that Li be completely covered in the case where not contacting with the gold thin film 46 for being used as negative electrode collector₃Fe₂(PO₄)₃Film 49.In this way, obtaining all solid lithium secondary battery as shown in Figure 37.At this point, the metal mask being open using 20mm × 12mm.

The all solid lithium secondary battery so obtained is referred to as battery 11.Anode active material layer, solid electrolyte layer and each filling rate of anode active material layer are about 100%.

(battery 12)

In addition to using LiMnPO₄LiCoPO is replaced as positive electrode active materials₄Outside, battery 12 is prepared according to mode identical with battery 11.

(battery 13)

In addition to using FePO₄Li is replaced as negative electrode active material₃Fe₂(PO₄)₃Outside, battery 13 is prepared according to mode identical with battery 11.

(battery 14)

In addition to using LiFeP₂O₇Li is replaced as negative electrode active material₃Fe₂(PO₄)₃Outside, battery 14 is prepared according to mode identical with battery 11.

(comparative cell 6)

In addition to using LiCoO₂LiCoPO is replaced as positive electrode active materials₄And use Li₄Ti₅O₁₂Li is replaced as negative electrode active material₃Fe₂(PO₄)₃Outside, comparative cell 6 is prepared according to mode identical with battery 11.

(comparative cell 7)

In the preparation of all solid lithium secondary battery, anode active material layer, solid electrolyte layer and the anode active material layer of the laminated body that unannealed/crystallization is formed by sputtering.In addition to this, comparative cell 7 is prepared according to mode identical with battery 11.

It is to be charged and discharged battery 7-14 and comparative cell 5-7 with the current value of 10 μ A primary in -50 DEG C of atmosphere and 25 DEG C of environment temperature in dew point.Gained discharge capacity is expressed as initial discharge capacity.In addition, upper blanking voltage and lower blanking voltage has been displayed in Table 4.

Table 4

	Initial discharge capacity (μ Ah)	Upper blanking voltage (V)	Lower blanking voltage (V)
	Initial discharge capacity (μ Ah)	Upper blanking voltage (V)	Lower blanking voltage (V)	Battery 7	10.1	2.2	1.0
Battery 8	19.4	2.0	0.8	Battery 7	10.1	2.2	1.0
Battery 8	19.4	2.0	0.8	Battery 9	8.4	2.0	0.8
Battery 10	10.3	2.1	1.0	Battery 9	8.4	2.0	0.8
Battery 10	10.3	2.1	1.0	Comparative cell 5	0	3	1.5
Battery 11	13.4	2.2	1.0	Comparative cell 5	0	3	1.5
Battery 11	13.4	2.2	1.0	Battery 12	11.8	2.0	0.8
Battery 13	10.4	2.0	0.8	Battery 12	11.8	2.0	0.8
Battery 13	10.4	2.0	0.8	Battery 14	13.3	2.1	1.0
Comparative cell 6	0	3	1.5	Battery 14	13.3	2.1	1.0
Comparative cell 6	0	3	1.5	Comparative cell 7	0	2.6	1.0

As shown in table 4, comparative cell 5-7 cannot discharge.But battery 7-14 can be charged and discharged.

In comparative cell 5-6, due to heat treatment, the interface between interface and/or negative electrode active material and solid electrolyte between positive electrode active materials and solid electrolyte forms neither active material is also not the impurity phase of solid electrolyte.It may be because this reason, these interfaces become electrochemical deactivation.In comparative cell 7, positive electrode active materials, negative electrode active material and solid electrolyte are not annealed to crystallize.It may be because this reason, solid electrolyte does not show lithium-ion-conducting, and lithium ion charge/discharge site is not formed in positive electrode active materials and negative electrode active material, to be unable to charge/discharge.

As described above, it has shown that according to the present invention, it is bonded together between positive electrode active materials and solid electrolyte and negative electrode active material and solid electrolyte without forming impurity phase in their interface, these interfaces are electro-chemical activities and battery including the laminated body being capable of charge/discharge.

Then, in order to obtain charge/discharge cycle circle number when discharge capacity becomes initial discharge capacity 60%, it is so that battery 7-14 is received recharge and discharge cycles with the current value of 10 μ A under blanking voltage as shown in table 4 in -50 DEG C of atmosphere and 25 DEG C of environment temperature in dew point.Table 5 shows result.

Table 5

	Discharge capacity becomes the charge/discharge cycle circle number (circle number) when initial discharge capacity 60%
		Battery
7	297	Battery
7	297	Battery 8	281
Battery 9	316	Battery 8	281
Battery 9	316	Battery 10	293
Battery 11	507	Battery 10	293
Battery 11	507	Battery 12	498
Battery 13	521	Battery 12	498
Battery 13	521	Battery 14	501

Battery 7-10 can charge/discharge cycle about 300 enclose, and battery 11-14 can charge/discharge cycle about 500 enclose.

This clearly illustrates that the present invention can provide all solid lithium secondary battery with excellent cycle life characteristics.

Embodiment 1-5

Then, the sintered density of the second laminated body is checked.

(battery 15)

It is outer except through being sintered in the heating rate of 400 DEG C/h to 850 DEG C, battery 15 is prepared according to mode identical with battery 7.

(reference battery 16)

It is outer except through being sintered in the heating rate of 400 DEG C/h to 800 DEG C, reference battery 16 is prepared according to mode identical with battery 7.

The impedance of battery 15, reference battery 16 and battery 7 is detected at 1 khz.

Table 6 shows the impedance of the filling rate and these batteries of the laminated body used in battery 7, battery 15 and reference battery 16.As for filling rate, it is assumed that laminated body only by Li_1.3Al_0.3Ti_1.7(PO₄)₃Filling rate as shown in table 6 is obtained in the case where composition.

Table 6

	Filling rate (%)	Impedance (Ω)
	Filling rate (%)	Impedance (Ω)	Battery 7	83	3010
Battery 15	72	3520	Battery 7	83	3010
Battery 15	72	3520	Reference battery 16	55	144000

As shown in table 6, when the filling rate of the second laminated body is less than 70%, impedance increases sharply.This may be because positive electrode active material powder and solid electrolyte powder and/or negative electrode active material powder and the insufficient sintering of solid electrolyte powder lead to the reduction of lithium ion conduction path sizes.

Therefore, in the second laminated body that anode active material layer, solid electrolyte layer and the anode active material layer by combining form, every layer of filling rate is preferably both greater than 70%.

Embodiment 1-6

Next, checking influence of the moisture to battery.

(battery 17)

It is formed outside the collector made of Ag films on surface and anode active material layer surface except through sputtering at the anode active material layer in laminated body, prepares battery 17 according to mode identical with battery 7.

(battery 18)

As shown in Figure 38, battery 17 is placed in the metal-back 51 for being mounted with nylon washer 53.The opening of metal-back 51 is crimped on metal sealing plate 52, washer 53 is inserted into therebetween, obtains the button type sealed cell of 9mm diameter and 2.1mm height.The battery so obtained is known as battery 18.At this point, battery 17 is placed in metal-back, so that metal-back 51 is used as positive terminal and metal sealing plate 52 is used as negative pole end.In addition, nickel sponge metal tape 54 is inserted between metal-back 51 and battery 17, so that battery 17, metal-back and metal sealing plate are intimate contact with one another.

In Figure 38, battery 17 includes Ag films 55, anode active material layer 39a, solid electrolyte layer 39b, anode active material layer 39c and Ag films 56.

(battery 19)

The copper lead 57 of 0.5mm diameter is connect with the Ag films on the Ag films and anode active material layer side on 17 anode active material layer side of battery with solder flux 58, to provide positive terminal and negative pole end.As shown in Figure 39, epoxy resin 59 is used for resin mold to seal the battery 17 including Ag films, anode active material layer, solid electrolyte layer, anode active material layer and Ag films.The battery is referred to as battery 19.

(battery 20)

Other than the surface waterproofing in the heptane dispersion liquid that will there is copper lead to immerse fluorocarbon resin waterproof material as the battery 17 of positive terminal and negative pole end to make battery 17, battery 20 is prepared according to mode identical with battery 19.

In the following way, the discharge capacity of the battery 17-20 so obtained with Post-Storage Checkout before storage.

It then, is so that battery 17-20 is received charging and discharging with the current value of 10 μ A in the range of 1.0-2.6V, to obtain initial discharge capacity in -50 DEG C of atmosphere and 60 DEG C of environment temperature in dew point.Then, these batteries are charged into 2.6V, is then stored 30 days in the atmosphere of 60 DEG C of temperature and 90% relative humidity.It then, is that these battery discharges are made with the current value of 10 μ A in -50 DEG C of atmosphere and 25 DEG C of environment temperature in dew point.The initial discharge capacity and the discharge capacity after 30 days that table 7 shows these batteries.

Table 7

	Initial discharge capacity (μ Ah)	Discharge capacity (μ Ah) after 30 days
	Initial discharge capacity (μ Ah)	Discharge capacity (μ Ah) after 30 days	Battery
17	10.3	0	Battery
17	10.3	0	Battery 18	10.2	10.1
Battery 19	10.4	4.2	Battery 18	10.2	10.1
Battery 19	10.4	4.2	Battery 20	10.3	9.8

The initial discharge capacity of battery 17-20 is about 20 μ Ah and almost equal.Under high humidity conditions after storage in 30 days, battery 17 cannot discharge, and battery 19 shows capacity decline.The discharge capacity of battery 18 and battery 20 and their initial discharge capacity are of equal value after storage.

In the case where battery 17, when storage is exposed in wet atmosphere therebetween, liquid moisture film (i.e. laminated body surface) is formed on battery surface.Collector Ag may be made to ionize, and Ag Ion transfer causes short circuit due to the formation of liquid moisture film, cannot discharged so as to cause after storage in 30 days.

In the case where battery 19, capacity occurs as described above to be reduced, although it does not have in battery 17 greatly.Because undesirable air-tightness only can only be provided with resin mold, moisture enters in resin.It may be because this reason, ionize collector Ag, and Ag Ion transfer causes minute short circuit, so as to cause capacity reduction.

On the other hand, in the case where battery 18 and battery 20, or even after they are stored 30 days in moist conditions, their discharge capacity is maintained.Therefore, the result of battery 18 confirms that humid air can be blocked using the container with good air-tightness, and the result of battery 20 confirms to prevent to battery (laminated body) surface applied waterproof material and forms liquid film on battery surface.

As described above, when battery (laminated body) is mounted in the container with high-air-tightness or when with waterproof material treatment of battery (laminated body) surface, improves the processing of battery and the influence of the humidity of environmental gas can be reduced.

Embodiment 1-7

In the present embodiment, preparation has all solid lithium secondary battery of the second laminated body, and second laminated body includes the combination that two or more is each made of anode active material layer, solid electrolyte layer and anode active material layer.

(battery 21)

Firstly, preparation is by Li_1.3Al_0.3Ti_1.7(PO₄)₃The solid electrolyte powder of representative, by LiCo_0.5Ni_0.5PO₄The positive electrode active material powder of representative and by Li₃Fe₂(PO₄)₃The negative electrode active material powder of representative.

Mix solid electrolyte powder with polyvinyl butyral resin, the n-butyl acetate as solvent and the dibutyl phthalate as plasticizer for being used as binder, and mixture is mixed together 24 hours with zirconia balls in ball milling, prepares the slurry for being used to form solid electrolyte layer.

Then, solid electrolyte layer slurry is administered on the film carrier 60 being mainly made of polyester resin using scraper.Then, the slurry of dry application, obtains solid electrolyte green sheet 61 as shown in Figure 40 (thickness: 10 μm).It should be understood that the surface of film carrier 60 has the releasing agent layer being mainly made of Si.

Anode active material layer slurry is applied on another film carrier 60 with pattern as shown in Figure 41 by silk-screen printing, wherein the straight line 63 of five positive electrode active materials green sheets 62 is with the arrangement of zigzag pattern.Dry slurry obtains the positive green sheet of multiple predetermined patterns.Positive electrode active materials green sheet with a thickness of 3 μm.The width X of positive electrode active materials green sheet₁For 1.5mm, and the length X of positive electrode active materials green sheet₂For 6.8mm.Interval Y in every row between positive electrode active materials green sheet₁For 0.4mm, and line spacing Y₂For 0.3mm.

Then, preparation includes gold size of the commercially available polyvinyl butyral resin as binder.As shown in Figure 42, according to prepare identical pattern in positive electrode active materials green sheet, this gold size is administered on another film carrier 60 by silk-screen printing.Dry gold size, obtains positive electrode collector green sheet 64 (thickness: 1 μm).

Anode active material layer slurry is applied on another film carrier 60 with pattern as shown in Figure 43 by silk-screen printing, wherein arranging the straight line of five negative electrode active material green sheets 65 with the zigzag pattern opposite with positive electrode active materials green sheet.Negative electrode active material green sheet with a thickness of 5 μm.The width X of negative electrode active material green sheet₁, negative electrode active material green sheet length X₂, interval Y in every row between negative electrode active material green sheet₁With line spacing Y₂It is all identical with positive electrode active materials green sheet.

Then, as shown in Figure 44, according to prepare identical pattern in negative electrode active material green sheet, above-mentioned gold size is administered on another film carrier 60 by silk-screen printing.Dry gold size, obtains negative electrode collector green sheet 66 (thickness: 1 μm).

Then, the polyester film 68 of adhesive is fixed on carrier 67 two sides application.As shown in Figure 45, the face of solid electrolyte green sheet 61 not contacted with film carrier 60 is placed on polyester film 68.

Then, by applying 80kg/cm from upper direction film carrier 60²Pressure and 70 DEG C of heating, from solid electrolyte green sheet 61 remove film carrier 60, as shown in Figure 46.

Then, the solid electrolyte green sheet 61 ' prepared on another film carrier 60 ' in same manner described above is placed in solid electrolyte green sheet 61.Then, by applying pressure and heating from upper direction film carrier 60 ', green sheet 61 and 61 ' is bonded together and removing film carrier 60 ' from green sheet 61 '.

By repeating this operation 20 times, solid electrolyte green sheet group 69 as shown in Figure 47 (thickness: 200 μm) is produced.

Then, as shown in Figure 48, the multi-disc negative electrode active material green sheet 65 formed on slide glass 60 in the manner described above is placed in the solid electrolyte green sheet 61 formed on film carrier 60, so that negative electrode active material green sheet 65 is contacted with solid electrolyte green sheet 61.Then, apply 80kg/cm by having loaded the film carrier 60 of multi-disc negative electrode active material green sheet from upper direction²Pressure and 70 DEG C of heating, from negative electrode active material green sheet 65 remove film carrier 60.

Then, multi-disc is laminated in negative electrode active material green sheet and is supported on the negative electrode collector green sheet 66 on slide glass 60, so that they are concordant with negative electrode active material green sheet 65.Film carrier 60 by having loaded multi-disc negative electrode collector green sheet 66 from upper direction applies 80kg/cm²Pressure and 70 DEG C of heating, from negative electrode collector green sheet 66 remove film carrier 60.In addition, negative electrode active material green sheet 65 is laminated in negative electrode collector green sheet 66 in the same fashion, laminated body as shown in Figure 49 is obtained.Gained laminated body is referred to as cathode laminated body 70, comprising: which solid electrolyte green sheet 61 and multi-disc are laminated thereon the sub- laminated body in face, every sub- laminated body is made of two panels negative electrode active material green sheet and a piece of negative electrode active material green sheet being clipped between the two panels green sheet.

Then, as shown in Figure 50, the multi-disc positive electrode active materials green sheet 62 formed on film carrier 60 in the manner described above is placed in the solid electrolyte green sheet 61 formed on film carrier 60, so that positive electrode active materials green sheet 62 is contacted with solid electrolyte green sheet 61.Then, apply 80kg/cm by having loaded the film carrier 60 of multi-disc positive electrode active materials green sheet from upper direction²Pressure and 70 DEG C of heating, from positive electrode active materials green sheet 62 remove film carrier 60.

Then, multi-disc is laminated in positive electrode active materials green sheet 62 and is supported on the positive electrode active materials green sheet 64 on film carrier 60, so that they are concordant with the positive electrode active materials green sheet.Film carrier 60 by having loaded multi-disc positive electrode active materials green sheet 64 from upper direction applies 80kg/cm²Pressure and 70 DEG C of heating, from positive electrode active materials green sheet 64 remove film carrier 60.In addition, positive electrode active materials green sheet 62 is laminated in positive electrode active materials green sheet 64 in the same fashion, laminated body as shown in Figure 51 is obtained.Gained laminated body is referred to as positive laminated body 71, comprising: which solid electrolyte green sheet 61 and multi-disc are laminated thereon the sub- laminated body in face, every sub- laminated body is made of two panels positive electrode active materials green sheet and a piece of positive electrode active materials green sheet being clipped between the two panels green sheet.

Then, as shown in Figure 52, cathode laminated body 70 is placed in the solid electrolyte green sheet group 69 on carrier 67.By applying 80kg/cm from upper direction film carrier 60²Pressure and 70 DEG C of heating, from cathode laminated body 70 remove film carrier 60.In this way, cathode laminated body 70 has been laminated in solid electrolyte green sheet 69, so that negative electrode active material green sheet contacts.

Equally, positive laminated body 71 is placed in cathode laminated body 70, so that the positive electrode active materials green sheet of positive laminated body 71 is contacted with the solid electrolyte green sheet of cathode laminated body 70.By applying 80kg/cm from upper direction film carrier 60²Pressure and 70 DEG C of heating, from positive laminated body 71 remove film carrier 60.In this way, positive laminated body 71 has been laminated in cathode laminated body 70.After cathode laminated body and positive laminated body has been laminated, the zigzag pattern and the zigzag pattern of positive electrode active materials green sheet straight line of negative electrode active material green sheet straight line are opposite facing.

By repeating aforesaid operations, laminated body 72 as shown in Figure 53 is obtained, is made of the positive laminated body of solid electrolyte green sheet group, five cathode laminated bodies and four.That end back to solid electrolyte green sheet group of laminated body 72 is cathode laminated body in the stacking direction.

Finally, in laminated body 72 back to 20 solid electrolyte green sheets are laminated in the cathode laminated body at that end of solid electrolyte green sheet group.This laminated body piece is removed from the carrier 67 with polyester film 68.

The laminated body piece is cut, green part 73 is obtained.Figure 54-56 shows the green part.Figure 54 is the top view of green part 73.Figure 55 is the longitudinal sectional view obtained along line X-X.Figure 56 is the longitudinal sectional view obtained along line Y-Y.

As shown in Figure 56, green part 73 has the following structure: multiple combinations has been laminated, each combination includes positive electrode active materials green sheet 74, solid electrolyte green sheet 75 and negative electrode active material green sheet 76.By being sintered this green part, the laminated body including at least one anode active material layer, solid electrolyte layer and anode active material layer entire combination can be obtained.By changing positive laminated body, the quantity of the adjustable entire combination of quantity of solid electrolyte green sheet and cathode laminated body.

In addition, the green part obtained in the present embodiment has hexahedral shape, and as shown in Figure 55, one end of negative electrode active material green sheet 76 and negative electrode collector green sheet 78 is exposed at a hexahedral face.On opposite facing face, one end of positive electrode active materials green sheet 74 and positive electrode collector green sheet 77 is exposed.That is, by using above-mentioned preparation method positive electrode collector and negative electrode collector can be exposed in the different surfaces region of laminated body.Furthermore it is possible to expose positive electrode collector and negative electrode collector in the different surfaces region of laminated body by using other methods other than the above method.

In the present embodiment, other faces other than the two described faces are covered with solid electrolyte layer.

Then, green part is heated to 400 DEG C with the rate of heat addition of 400 DEG C/h in air and is maintained 5 hours at 400 DEG C, so that organic substance such as binder and plasticizer are sufficiently decomposed due to heat.Then, 900 DEG C are heated to the rate of heat addition of 400 DEG C/h and room temperature is rapidly cooled to the cooling velocity of 400 DEG C/h.In this way, sintering green part, obtains sintered body (the second laminated body).The sintered body has width, the depth of about 1.6mm and the height of about 0.45mm of about 3.2mm.

It is assumed that the sintered body only by Li_1.3Al_0.3Ti_1.7(PO₄)₃In the case where composition, according to the filling rate for the green part for determining sintering with mode identical in embodiment 1-2.As a result, the filling rate of sintered body is about 83%.

In addition, with the polishing section of SEM observation sintered body.As a result, positive electrode collector and negative electrode collector all have about 0.3 μm of thickness.In addition, the anode active material layer on positive electrode collector side has about 1 μm of thickness, and the anode active material layer on negative electrode collector side has about 2 μm of thickness.In addition, it was demonstrated that sintered body is densely sintered, almost without hole.

It include the outer collector paste of copper and glass powder to the face 80 for exposing positive electrode collector of sintered body 79 and the face 81 for exposing negative electrode collector application.Then, the sintered body of outer collector paste is heat-treated 1 hour at 600 DEG C in nitrogen atmosphere application.As a result, forming the outer collector 82 of anode and the outer collector 83 of cathode as shown in figure 57.In this way, preparing all solid lithium secondary battery.The battery is referred to as battery 21.

(battery 22)

In addition to using LiMnPO₄Instead of LiCo_0.5Ni_0.5PO₄Outside, battery 22 is prepared according to mode identical with battery 21.

(battery 23)

In addition to using FePO₄Instead of Li₃Fe₂(PO₄)₃Outside, battery 23 is prepared according to mode identical with battery 21.

(battery 24)

In addition to using LiFeP₂O₇Instead of Li₃Fe₂(PO₄)₃Outside, battery 24 is prepared according to mode identical with battery 21.

(comparative cell 8)

In addition to using LiCoO₂Instead of LiCo_0.5Ni_0.5PO₄And use Li₄Ti₅O₁₂Instead of Li₃Fe₂(PO₄)₃Outside, comparative cell 8 is prepared according to mode identical with battery 21.

(battery 25)

In addition to using Li_1.3Al_0.3Ti_1.7(PO₄)₃Instead of Li₃Fe₂(PO₄)₃Outside, battery 25 is prepared according to mode identical with battery 21.

(battery 26)

Preparation is by Li_1.3Al_0.3Ti_0.7(PO₄)₃The solid electrolyte powder of representative, by LiCo_0.5Ni_0.5PO₄The positive electrode active material powder of representative and by Li₃Fe₂(PO₄)₃The negative electrode active material powder of representative.

Mix positive electrode active material powder with polyvinyl butyral resin, n-butyl acetate, dibutyl phthalate and palladium powder, and mixture is mixed together 24 hours with zirconia balls in ball milling, prepares the slurry for being used to form anode active material layer.In gained anode active material layer, palladium powder is used as the collector of three-dimensional network form.

Using above-mentioned negative electrode active material, the slurry for being used to form anode active material layer is prepared according to mode identical with anode active material layer slurry.

Using solid electrolyte layer slurry, solid electrolyte green sheet (thickness: 10 μm) is formed on film carrier according to identical mode in battery 21.

Using anode active material layer slurry, according to forming the positive electrode active materials green sheet 84 that multi-disc includes collector in the solid electrolyte green sheet 61 on film carrier 60 with pattern as shown in Figure 58 with identical mode in battery 21.In this way, preparing the positive plate 85 including solid electrolyte green sheet and positive electrode active materials green sheet.The thickness of every positive electrode active materials green sheet is 4 μm.

Using anode active material layer slurry, according to forming the negative electrode active material green sheet 86 that multi-disc includes collector in the solid electrolyte green sheet 61 on film carrier 60 with pattern as shown in Figure 59 with identical mode in battery 21.In this way, preparing the negative electrode tab 87 including solid electrolyte green sheet and negative electrode active material green sheet.The thickness of every negative electrode active material green sheet is 7 μm.

The width X of positive electrode active materials green sheet₁, positive electrode active materials green sheet length X₂, interval Y in every row between positive electrode active materials green sheet₁With line spacing Y₂It is all identical with battery 21.This is equally applicable to negative electrode active material green sheet.

Then, 20 solid electrolyte green sheets are laminated on the carrier for the polyester film for having adhesive with two sides application according to identical mode in battery 21, are formed solid electrolyte green sheet group (thickness: about 200 μm).

Then, as shown in Figure 60, piece 87 is placed in solid electrolyte green sheet group 69 according to identical mode in battery 21.By applying 80kg/cm from upper direction film carrier 60²Pressure and 70 DEG C of heating, from solid electrolyte green sheet 61 remove film carrier 60.In this way, negative electrode tab 87 has been laminated in solid electrolyte green sheet group.Equally, positive plate 85 is laminated in the solid electrolyte green sheet of negative electrode tab 87, so that the positive electrode active materials green sheet of positive plate 85 contacts.Then, film carrier is removed from solid electrolyte green sheet in same manner described above.

By repeating these operations, the laminated body 88 including a piece of negative electrode tab 87 and four positive plates 85 is formed as shown in Figure 61.Then, laminates are obtained back to 20 solid electrolyte green sheets of stacking in the negative electrode tab 87 at one end of solid electrolyte green sheet group in laminated body 88.

The laminated body piece is cut, green part is obtained.Figure 62-64 shows the green part.Figure 62 is the top view of green part 89.Figure 63 is the longitudinal sectional view along the green part 89 of line X-X Figure 62 obtained.Figure 64 is the longitudinal sectional view along the green part 89 of line Y-Y Figure 62 obtained.

Other than providing the collector of three-dimensional network form in active material green sheet, green part 89 and the green part 73 (Figure 54-56) prepared for battery 21 are almost identical.That is, green part 89 has the following structure: multiple combinations have been laminated, each combination includes positive electrode active materials green sheet 90, solid electrolyte green sheet 91 and negative electrode active material green sheet 92.In addition, exposing one end of positive electrode active materials green sheet and one end of negative electrode active material green sheet in the different surfaces region of green part.

Then, green part is heated to 400 DEG C with the rate of heat addition of 400 DEG C/h in air and is maintained 5 hours at 400 DEG C, so that organic substance such as binder and plasticizer are sufficiently decomposed due to heat.Then, 900 DEG C are heated to the rate of heat addition of 400 DEG C/h and room temperature is rapidly cooled to the cooling velocity of 400 DEG C/h.In this way, sintering green part.The sintered body so obtained has width, the depth of about 1.6mm and the height of about 0.45mm of about 3.2mm.

It is assumed that the sintered body only by Li_1.3Al_0.3Ti_1.7(PO₄)₃In the case where composition, according to the filling rate for determining sintered body with identical mode in embodiment 1-2.As a result, the filling rate of sintered body is about 83%.

In addition, with the polishing section of SEM observation sintered body the result shows that anode active material layer with about 0.2 μm of thickness and anode active material layer with about 4 μm of thickness.In addition, it was demonstrated that sintered body is densely sintered, almost without hole.

It include the outer collector paste of copper and glass powder to the face 94 for exposing positive electrode collector of the sintered body 93 of acquisition and its face 95 for exposing negative electrode collector application.Then, the sintered body of outer collector paste is heat-treated 1 hour at 600 DEG C in nitrogen atmosphere application.As a result, forming the outer collector 96 of anode and the outer collector 97 of cathode as shown in Figure 65.In this way, preparing all solid lithium secondary battery.The battery is referred to as battery 26.

It is to be charged and discharged battery 21-26 and comparative cell 8 once in -50 DEG C of atmosphere and 25 DEG C of environment temperature with the current value of 10 μ A in dew point.Gained discharge capacity is expressed as initial discharge capacity in table 8.In addition, upper blanking voltage and lower blanking voltage has been displayed in Table 8.

Table 8

	Initial discharge capacity (μ Ah)	Upper blanking voltage (V)	Lower blanking voltage (V)
	Initial discharge capacity (μ Ah)	Upper blanking voltage (V)	Lower blanking voltage (V)	Battery 21	4.9	2.2	1.0
Battery 22	6.5	1.8	0.5	Battery 21	4.9	2.2	1.0
Battery 22	6.5	1.8	0.5	Battery 23	4.8	2.0	0.8
Battery 24	4.5	2.1	0.9	Battery 23	4.8	2.0	0.8
Battery 24	4.5	2.1	0.9	Battery 25	4.2	2.5	1.3
Battery 26	4.9	2.2	1.0	Battery 25	4.2	2.5	1.3
Battery 26	4.9	2.2	1.0	Comparative cell 8	0	3.0	1.4

Battery 21-26 can discharge.But comparative cell 8 cannot discharge.Above result indicate that the present invention can provide all solid lithium secondary battery for capableing of charge/discharge.In addition, battery capacity can be increased by increasing anode active material layer, the quantity of solid electrolyte layer and anode active material layer.Therefore, by increasing the quantity of layer laminate body, battery capacity can be increased.

Next, the battery of evaluation surface treatment.

(battery 27)

By applying the normal heptane dispersion liquid of fluorocarbon resin waterproof material to it, water-proofing treatment is applied in the part to outside the anode of battery 21 outside collector 82 and cathode other than collector 83.The battery is referred to as battery 27.

(battery 28)

Part application to outside the anode of battery 21 outside collector 82 and cathode other than collector 83 includes 72 weight %SiO₂- 1 weight %Al₂O₃- 20 weight %Na₂The slurry (750 DEG C of softening point) of O-3 weight %MgO-4 weight %CaO.Dry applied slurry, is then heat-treated at 700 DEG C.As a result, as shown in fig. 66, being partially coated with glassy layer 98 other than the outer collector 83 of the outer collector 82 of anode and cathode of battery 21.The battery is referred to as battery 28.

(battery 29)

Application is comprising by (0.3Na on part to outside the anode of battery 21 outside collector and cathode other than collector₂O-0.7CaO)0.5Al₂O₃·4.5SiO₂The softening point represented is 750 DEG C of clear frit chylema material.It dries applied slurry and is heat-treated at 700 DEG C.As a result, being partially coated with glaze layer other than collector outside the outer collector of 21 anode of battery and cathode.The battery is referred to as battery 29.

By battery 21 and battery 27-29 in 60 DEG C of environment temperature and the hot and wet container of 90% relative humidity, stored 30 days under the constant pressure of 2.2V.Then, these batteries are taken out from container and are discharged under the current value of 10 μ A, and discharge capacity is obtained.Table 9 shows result.

Table 9

	Discharge capacity (μ Ah)
	Discharge capacity (μ Ah)	Battery 21	0.3
Battery 27	3.5	Battery 21	0.3
Battery 27	3.5	Battery 28	4.8
Battery 29	4.9	Battery 28	4.8

After saving under high temperature and humidity state, battery 21 can hardly discharge.On the other hand, battery 27-29 shows relatively good discharge capacity.

In battery 21, due to insufficient sintering, the outmost solid electrolyte of battery may be porous.When storing this outermost solid electrolyte layer in wet atmosphere is porous battery, moisture enters in battery, so that Nintaus's electrode current collector is ionized.The gold of ionization is mobile to anode active material layer by solid electrolyte layer, is reduced there and gold is deposited.The gold of deposition causes short circuit between anode active material layer and anode active material layer.This may be why battery 21 can hardly discharge.

Through water repellent treatment battery 27, with roasting low-melting glass battery 28 and with roasting glaze layer battery 29 in the case where, it is therefore prevented that moisture enters these batteries from the outside.This may be to obtain good discharge capacity why without causing internal short-circuit.

As described above, this example demonstrates that can provide even stored in heat and wet atmosphere after also highly reliable all solid lithium secondary battery.

Embodiment 1-8

(battery 30)

Firstly, preparation is by Li_1.3Al_0.3Ti_1.7(PO₄)₃The solid electrolyte powder of representative and by LiFePO₄The positive electrode active material powder of representative.

Mix solid electrolyte powder with polyvinyl butyral resin, the n-butyl acetate as solvent and the dibutyl phthalate as plasticizer for being used as binder, and mixture is mixed together 24 hours with zirconia balls in ball milling, forms the slurry for being used to form solid electrolyte layer.

Equally, the slurry for being used to form anode active material layer is prepared according to mode identical with solid electrolyte layer slurry.

Then, solid electrolyte layer slurry is administered on the film carrier 99 being mainly made of polyester resin using scraper.Then, the slurry of dry application, forms solid electrolyte green sheet 100 (thickness: 10 μm) as shown in figure 67.The surface of film carrier 99 has the releasing agent layer being mainly made of Si.

Anode active material layer slurry is applied on another film carrier 99 with the pattern as shown in Figure 68 by silk-screen printing, wherein arranging the straight line 102 of five positive electrode active materials green sheets 101 with zigzag pattern.Dry slurry obtains the positive green sheet 101 of multiple predetermined patterns.Positive electrode active materials green sheet with a thickness of 3 μm.The width X of positive electrode active materials green sheet₁For 1.5mm, and the length X of positive electrode active materials green sheet₂For 6.8mm.Interval Y in every row between positive electrode active materials green sheet₁For 0.4mm, and line spacing Y₂For 0.3mm.

Then, preparation includes copper glue of the commercially available polyvinyl butyral resin as binder.As shown in Figure 69, according to prepare identical pattern in positive electrode active materials green sheet, this copper glue is administered on another film carrier 99 by silk-screen printing.Dry copper glue, obtains multi-disc positive electrode collector green sheet 103 (thickness: 1 μm).

Then, above-mentioned copper glue is applied with opposite with the pattern of positive electrode active materials green sheet zigzag pattern as shown in Figure 70 on another film carrier 99 by silk-screen printing.Dry copper glue, obtains multi-disc negative electrode collector green sheet 104 (thickness: 1 μm).At this point, the width X of negative electrode collector green sheet₁, negative electrode collector green sheet length X₂, interval Y in every row between negative electrode collector green sheet₁With line spacing Y₂It is all identical with positive electrode active materials green sheet.

Then, the polyester film 106 of adhesive is fixed on carrier 105 two sides application.As shown in Figure 71, the face of solid electrolyte green sheet 100 not contacted with film carrier 99 is placed on polyester film 106.

Then, by applying 80kg/cm from upper direction film carrier 99²Pressure and 70 DEG C of heating, from solid electrolyte green sheet 100 remove film carrier 99, as shown in Figure 72.

Then, the solid electrolyte green sheet 100 ' formed on another film carrier 99 ' in same manner described above is placed in solid electrolyte green sheet 100.Then, by applying pressure and heating from upper direction film carrier 99 ', green sheet 100 and 100 ' is bonded together and removing film carrier 99 ' from green sheet 100 '.

By repeating this operation 20 times, the solid electrolyte green sheet group 107 as shown in Figure 73 (thickness: about 200 μm) is produced.

Then, as shown in Figure 74, the multi-disc negative electrode collector green sheet 104 formed on slide glass 99 in the manner described above is placed in the solid electrolyte green sheet 100 formed on film carrier 99, so that negative electrode collector green sheet 104 is contacted with solid electrolyte green sheet 100.Then, apply 80kg/cm by having loaded the film carrier 99 of multi-disc negative electrode active material green sheet from upper direction²Pressure and 70 DEG C of heating, from negative electrode collector green sheet 104 remove film carrier 99.In this way, as shown in Figure 75, cathode-solid electrolyte sheet 108 is obtained, the negative electrode collector green sheet 104 loaded including solid electrolyte green sheet 100 and above.

Then, as shown in figure 76, the multi-disc positive electrode active materials green sheet 101 formed on slide glass 99 in the manner described above is placed in the solid electrolyte green sheet 100 formed on film carrier 99, so that positive electrode active materials green sheet is contacted with solid electrolyte green sheet.Then, apply 80kg/cm by having loaded the film carrier 99 of multi-disc positive electrode active materials green sheet from upper direction²Pressure and 70 DEG C of heating, from positive electrode active materials green sheet 101 remove film carrier 99.

Then, multi-disc is laminated in positive electrode active materials green sheet 101 and is supported on the positive electrode collector green sheet 103 on film carrier 99, so that they are concordant with positive electrode active materials green sheet 101.Film carrier 99 by having loaded multi-disc positive electrode collector green sheet 103 from upper direction applies 80kg/cm²Pressure and 70 DEG C of heating, from positive electrode collector green sheet 103 remove film carrier 99.In addition, positive electrode active materials green sheet 101 is laminated in positive electrode collector green sheet 103 in the same fashion, the laminated body as shown in Figure 77 is obtained.Gained laminated body is referred to as positive laminated body 109, comprising: which solid electrolyte green sheet 100 and multi-disc are laminated thereon the sub- laminated body (sub-laminate) in face, every sub- laminated body is made of two panels positive electrode active materials green sheet and a piece of positive electrode collector green sheet being clipped between the two panels green sheet.

Then, as shown in Figure 78, cathode-solid electrolyte sheet 108 is placed in the solid electrolyte green sheet group 107 on carrier 105.By applying 80kg/cm from upper direction film carrier 99²Pressure and 70 DEG C of heating, from cathode-solid electrolyte sheet 108 remove film carrier 99.In this way, cathode-solid electrolyte sheet 108 is laminated in solid electrolyte green sheet group 107, so that negative electrode collector green sheet 104 is contacted with solid electrolyte green sheet group.

Equally, positive laminated body 109 is placed on cathode-solid electrolyte sheet 108, so that the positive electrode active materials green sheet of positive laminated body 109 is contacted with the solid electrolyte green sheet of cathode-solid electrolyte sheet 108.By applying 80kg/cm from upper direction film carrier 99²Pressure and 70 DEG C of heating, from positive laminated body 109 remove film carrier 99.In this way, positive laminated body 109 has been laminated on cathode-solid electrolyte sheet 108.After cathode-solid electrolyte sheet and positive laminated body has been laminated, the zigzag pattern and the zigzag pattern of positive electrode active materials green sheet straight line of negative electrode collector green sheet straight line are opposite facing.

By repeating aforesaid operations, laminated body 110 as shown in Figure 79 are obtained, are made of the positive laminated body of solid electrolyte green compact sheet laminate, five cathode-solid electrolyte sheets and four.That end that facing away from solid electrolyte green sheet group of laminated body 100 is cathode-solid electrolyte sheet 108 in the stacking direction.

Finally, 20 solid electrolyte green sheets are laminated on cathode-solid electrolyte sheet at that end of the opposite solid electrolyte green sheet group of laminated body 110.This laminated body piece is removed from the carrier 105 with polyester film 106.

The laminated body piece is cut, green part 111 is obtained.Figure 80-82 shows the green part.Figure 80 is the top view of green part 111.Figure 81 is the longitudinal sectional view obtained along line X-X.Figure 82 is the longitudinal sectional view obtained along line Y-Y.

As shown in Figure 82, green part 111 has the following structure: multiple positive electrode active materials laminated bodies has been laminated, each laminated body includes cathode-solid electrolyte sheet that positive electrode active materials green sheet 101, positive electrode collector green sheet 103 and multi-disc each include negative electrode collector piece 104.By being sintered this green part, the laminated body including at least one anode active material layer and cathode-solid electrolyte layer entire combination can be obtained.By the quantity for changing positive laminated body and the adjustable entire combination of cathode-solid electrolyte layer quantity.

In addition, the green part obtained in the present embodiment has hexahedral shape, and as shown in Figure 81, one end of negative electrode collector green sheet 104 is exposed at a hexahedral face.On opposite facing face, one end of positive electrode active materials green sheet 101 and positive electrode collector green sheet 103 is exposed.That is, by using above-mentioned preparation method positive electrode collector and negative electrode collector can be exposed in the different surfaces region of laminated body.In addition, other methods other than the above method also can be used in order to which the different surfaces region in laminated body exposes positive electrode collector and negative electrode collector.

In sintering furnace, green part is heat-treated in the atmosphere gas by the first atmosphere gas and vapour composition.The first atmosphere gas used is that have the gas of low oxygen partial pressure and have CO₂/H₂/N₂The composition of=4.99/0.01/95.The vapour volume for including in the atmosphere gas is 5%.Under 700 DEG C and 1 atmospheric pressure, the flow velocity for supplying the atmosphere gas in furnace is 12L/min.Start to supply atmosphere gas into furnace when furnace temperature reaches 200 DEG C.

Green part is heated to 700 DEG C with the rate of heat addition of 100 DEG C/h and is maintained 5 hours at 700 DEG C.Then, 900 DEG C are heated to the rate of heat addition of 400 DEG C/h and room temperature is rapidly cooled to the cooling velocity of 400 DEG C/h.Stop supplying gas into furnace when furnace temperature becomes 200 DEG C.In this way, sintering green part, obtains sintered body.The sintered body has width, the depth of about 1.6mm and the height of about 0.45mm of about 3.2mm.

In addition, with the polishing section of SEM observation sintered body.As a result, positive electrode collector and negative electrode collector all have about 0.3 μm of thickness.In addition, the anode active material layer on positive electrode collector side has about 1 μm of thickness.Furthermore, it was demonstrated that sintered body is densely sintered, almost without hole.

It include the outer collector paste of copper and glass powder to the face 113 for exposing positive electrode collector of sintered body 112 and its face 114 for exposing negative electrode collector application.Then, it is heat-treated the sintered body that applied outer collector paste 1 hour at 600 DEG C.As a result, forming the outer collector 115 of anode and the outer collector 116 of cathode as shown in Figure 83.In this way, preparing all solid lithium secondary battery.The battery is referred to as battery 30.

In the CO that this group becomes₂/H₂/N₂In the gas of the low oxygen partial pressure of=4.99/0.01/95, the balanced reaction represented below by equation (2) and equation (3) occurs:

CO₂→CO+1/2O₂ (2)

H₂+1/2O₂→H₂O (3)

Oxygen is generated in the reaction of equation (2), and consumes oxygen in the reaction of equation (3).Therefore, the atmosphere gas includes to divide nearly constant oxygen.

(battery 31-34)

Other than the amount for the steam for including in mixed gas to be changed into 20 volume %, 30 volume %, 50 volume % and 90 volume % respectively, battery 31-34 is prepared according to mode identical with battery 30.

(reference battery 35)

In addition to using group to become CO₂/H₂/N₂The gas of=4.99/0.01/95 is as low oxygen partial pressure gas and does not add outside steam, prepares reference battery 35 according to mode identical with battery 30.

(reference battery 36)

In addition to using air that group is replaced to become CO₂/H₂/N₂The low oxygen partial pressure gas of=4.99/0.01/95 and the amount for the steam for including in atmosphere gas is changed into outside 30 volume %, prepares reference battery 36 according to mode identical with battery 30.

(reference battery 37)

In addition to using purity to replace group to become CO by the high-purity argon gas of 4N₂/H₂/N₂The low oxygen partial pressure gas of=4.99/0.01/95 and the amount for the steam for including in atmosphere gas is changed into outside 30 volume %, prepares reference battery 37 according to mode identical with battery 30.

(reference battery 38)

It is high-purity CO of 4N in addition to using purity₂Become CO instead of group₂/H₂/N₂The low oxygen partial pressure gas of=4.99/0.01/95 and the amount for the steam for including in atmosphere gas is changed into outside 30 volume %, prepares reference battery 38 according to mode identical with battery 30.

(reference battery 39)

It is high-purity H of 4N in addition to using purity₂Become CO instead of group₂/H₂/N₂The low oxygen partial pressure gas of=4.99/0.01/95 and the amount for the steam for including in atmosphere gas is changed into outside 30 volume %, prepares reference battery 39 according to mode identical with battery 30.

(battery 40)

In addition to using LiCoPO₄Outside as positive electrode active materials, battery 40 is prepared according to mode identical with battery 32.

For battery 30-34 and battery 40 and reference battery 35-39, it is assumed that the sintered body only by Li_1.3Al_0.3Ti_1.7(PO₄)₃In the case where composition, according to the filling rate for determining every body sintered body with identical mode in embodiment 1-2.Table 10 shows result.In addition, table 10 shows the additive amount and-log of the type of the first atmosphere, steam₁₀PO₂Value.

Table 10

	The first atmosphere	The quantity of steam (volume %) for including in atmosphere gas	Filling rate (%)	-log₁₀PO₂ (700℃)
	The first atmosphere		Filling rate (%)	-log₁₀PO₂ (700℃)	Battery 30	CO₂/H₂/N₂=99/0.01/95	5	78	15
Battery 31	CO₂/H₂/N₂=99/0.01/95	20	80	14	Battery 30	CO₂/H₂/N₂=99/0.01/95	5	78	15
Battery 31	CO₂/H₂/N₂=99/0.01/95	20	80	14	Battery 32	CO₂/H₂/N₂=99/0.01/95	30	82	13
Battery 33	CO₂/H₂/N₂=99/0.01/95	50	83	13	Battery 32	CO₂/H₂/N₂=99/0.01/95	30	82	13
Battery 33	CO₂/H₂/N₂=99/0.01/95	50	83	13	Battery 34	CO₂/H₂/N₂=99/0.01/95	90	83	12
Reference battery 35	CO₂/H₂/N₂=99/0.01/95	0	51	16	Battery 34	CO₂/H₂/N₂=99/0.01/95	90	83	12
Reference battery 35	CO₂/H₂/N₂=99/0.01/95	0	51	16	Reference battery 36	Air	30	73	0.7
Reference battery 37	Ar	30	75	7	Reference battery 36	Air	30	73	0.7
Reference battery 37	Ar	30	75	7	Reference battery 38	CO ₂	30	76	7
Reference battery 39	H ₂	30	59	22	Reference battery 38	CO ₂	30	76	7
Reference battery 39	H ₂	30	59	22	Battery 40	CO₂/H₂/N₂=99/0.01/95	30	85	13

Battery 30-34 shows about 80% preferable filling rate, unrelated with the amount of steam.Battery 40 also shows 85% preferable filling rate.

On the other hand, reference battery 35 and reference battery 39 show the filling rate lower than 60%, this shows almost without sintering.The sintered body of these reference batteries is all black.This shows that in these reference batteries, binder and plasticizer due to thermal decomposition carbonization and therefore hinder the sintering of green sheet.

In the case where reference battery 39, because of the H at 700 DEG C₂/H₂The equilibrium partial pressure of oxygen is about 10 in the atmosphere gas of O=7/3^-22Atmospheric pressure, this is low-down, so generated carbon can retain.

In addition, these

reference batteries

35 and 39 are crisp, therefore ruptured during the processing when applying outer collector.

In battery 30-34 and battery 40, their sintered body is almost white.In atmosphere gas as shown in table 10, the equilibrium oxygen partial pres-sure at 700 DEG C is estimated as about 10^-16Atmospheric pressure.In the case, it may be reduced due to steam molecule amount, binder and plasticizer are discharged rapidly from system and eliminate by-product carbon by very small amount of oxygen, to be sintered progress.

In addition, although their filling rate is slightly poorer than battery 30-34 and battery 40, their sintered body is almost also white in reference battery 36-38.

Next, being to be charged and discharged battery 30-34 and battery 40 in -50 DEG C of atmosphere and 25 DEG C of environment temperature with the current value of 10 μ A and reference battery 36-38 is primary in dew point.Wherein, 2.0V is set by upper blanking voltage and set 0V for lower blanking voltage.In addition, being in the same manner charged and discharged battery 40 other than setting 5.0V for upper blanking voltage and setting 0V for lower blanking voltage.The discharge capacity obtained according to the above method is shown as initial discharge capacity in table 11.

Table 11

	The first atmosphere	The quantity of steam (volume %) for including in atmosphere gas	Initial discharge capacity (μ Ah)
	The first atmosphere		Initial discharge capacity (μ Ah)	Battery 30	CO₂/H₂/N₂=99/0.01/95	5	6.3
Battery 31	CO₂/H₂/N₂=99/0.01/95	20	6.5	Battery 30	CO₂/H₂/N₂=99/0.01/95	5	6.3
Battery 31	CO₂/H₂/N₂=99/0.01/95	20	6.5	Battery 32	CO₂/H₂/N₂=99/0.01/95	30	6.6
Battery 33	CO₂/H₂/N₂=99/0.01/95	50	6.8	Battery 32	CO₂/H₂/N₂=99/0.01/95	30	6.6
Battery 33	CO₂/H₂/N₂=99/0.01/95	50	6.8	Battery 34	CO₂/H₂/N₂=99/0.01/95	90	6.7
Reference battery 36	Air	30	0	Battery 34	CO₂/H₂/N₂=99/0.01/95	90	6.7
Reference battery 36	Air	30	0	Reference battery 37	Ar	30	0.5
Reference battery 38	CO ₂	30	0.3	Reference battery 37	Ar	30	0.5
Reference battery 38	CO ₂	30	0.3	Battery 40	CO₂/H₂/N₂=99/0.01/95	30	2.8

Battery 30-34 shows the initial discharge capacity greater than 6 μ Ah.In addition, battery 40 shows the initial discharge capacity of 2.8 μ Ah.On the other hand, the charge/discharge of reference battery 36-38 is nearly impossible.Especially in reference battery 36, because being roasted in air atmosphere, LiFePO₄It is transformed into such as Li₃Fe₂(PO₄)₃Fe (III) compound and current collector material Cu be oxidized and cannot act as collector.It may be because this reason, charge/discharge is impossible.

On the other hand, in the atmosphere gas for being used to prepare reference battery 37-38, equilibrium oxygen partial pres-sure is estimated as about 10 at 700 DEG C^-7Atmospheric pressure.Therefore, LiFePO₄It is transformed into such as Li₃Fe₂(PO₄)₃Fe (III) compound, and may be because this reason, electric discharge is nearly impossible.

It is 10 from the equilibrium oxygen partial pres-sure at 700 DEG C that above-mentioned formula (1) calculates^-17.1Atmosphere is depressed into 10^-11.8Atmospheric pressure.It can be seen that in equilibrium oxygen partial pres-sure battery 30-34 within this range, it is suppressed that the oxidation of collector and active material Fe (II) arrive the oxidation of Fe (III), and eliminate binder by oxygen and carbon that plasticizer thermal decomposition generates.Therefore it is believed that can produce all solid lithium secondary battery with good charging/discharging capacity by suitably adjusting partial pressure of oxygen.

In addition, preferably low oxygen partial pressure gas includes the gas such as CO that can discharge oxygen in order to make the partial pressure for the oxygen for including in low oxygen partial pressure gas atmosphere remain constant₂With the gas such as H reacted with oxygen₂Mixture.

Embodiment 2-1

Next, preparing following battery and comparative cell, and it is charged and discharged under predetermined circumstances to obtain discharge capacity.

(battery 2-1)

In addition to making 750 DEG C of solid electrolyte layer slurry and softening point and by 72 weight %SiO₂- 1 weight %Al₂O₃- 20 weight %Na₂The amorphous oxide powder mixing that O-3 weight %MgO-4 weight %CaO is represented, so that the weight ratio between solid electrolyte powder and amorphous oxide powder is 97: 3, and the maximum sintering temperature of green sheet is changed to outside 700 DEG C from 900 DEG C, prepares battery 2-1 according to mode identical with battery 7.

It should be understood that the easy degree that positive electrode active materials are easy sintering and solid electrolyte layer is most difficult to be sintered, but is sintered between positive electrode active materials and negative electrode active material does not have much difference.Therefore, amorphous oxide is only added into solid electrolyte layer in the present embodiment.

Because anode active material layer and anode active material layer be compared with solid electrolyte layer it is sufficiently thin, it is assumed that sintering green part only by Li_1.3Al_0.3Ti_1.7(PO₄)₃In the case where composition, according to the filling rate for the green part for determining sintering with mode identical in previous embodiment 1-2.As a result, filling rate is about 73%.X-ray density of the filling rate of green part from [{ (green part weight)/(green part volume) } /] solid electrolyte)] × 100 calculating.

In addition, checking anode active material layer and anode active material layer with the polishing section of the green part of SEM observation sintering.Observation confirms anode active material layer and anode active material layer all has about 1 μm of thickness and anode active material layer and anode active material layer are densely sintered, almost without hole.

(battery 2-2)

Except through with the rate of heat addition of 400 DEG C/h be warming up to 800 DEG C replace being warming up to the rate of heat addition of 400 DEG C/h 700 DEG C it is outer to be sintered, prepare all-solid-state battery according to mode identical with battery 2-1.The battery is referred to as battery 2-2.It is assumed that green part only by Li_1.3Al_0.3Ti_1.7(PO₄)₃In the case where composition, the filling rate for being sintered green part is 93%.

(battery 2-3)

Except through with the rate of heat addition of 400 DEG C/h be warming up to 900 DEG C replace being warming up to the rate of heat addition of 400 DEG C/h 700 DEG C it is outer to be sintered, prepare all-solid-state battery according to mode identical with battery 2-1.The battery is referred to as battery 2-3.It is assumed that green part only by Li_1.3Al_0.3Ti_1.7(PO₄)₃In the case where composition, the filling rate for being sintered green part is 95%.

(battery 2-4)

Except through with the rate of heat addition of 400 DEG C/h be warming up to 1000 DEG C replace being warming up to the rate of heat addition of 400 DEG C/h 700 DEG C it is outer to be sintered, prepare all-solid-state battery according to mode identical with battery 2-1.The battery is referred to as battery 2-4.It is assumed that green part only by Li_1.3Al_0.3Ti_1.7(PO₄)₃In the case where composition, the filling rate for being sintered green part is 95%.

(battery 2-5)

Except through adding Li₄P₂O₇Solid electrolyte layer slurry is prepared as amorphous oxide, and is warming up to 800 DEG C instead of being warming up to 700 DEG C with the rate of heat addition of 400 DEG C/h to be sintered outside by the rate of heat addition with 400 DEG C/h, prepares battery 2-5 according to mode identical with battery 2-1.It is assumed that green part only by Li_1.3Al_0.3Ti_1.7(PO₄)₃In the case where composition, the filling rate for being sintered green part is 93%.

(comparative cell 2-1)

Except through with the rate of heat addition of 400 DEG C/h be warming up to 600 DEG C replace being warming up to the rate of heat addition of 400 DEG C/h 700 DEG C it is outer to be sintered, prepare comparative cell 2-1 according to mode identical with battery 2-1.It is assumed that green part only by Li_1.3Al_0.3Ti_1.7(PO₄)₃In the case where composition, the filling rate for being sintered green part is 57%.

(comparative cell 2-2)

Except through with the rate of heat addition of 400 DEG C/h be warming up to 1100 DEG C replace being warming up to the rate of heat addition of 400 DEG C/h 700 DEG C it is outer to be sintered, prepare comparative cell 2-2 according to mode identical with battery 2-1.It is assumed that green part only by Li_1.3Al_0.3Ti_1.7(PO₄)₃In the case where composition, the filling rate for being sintered green part is 93%.

(comparative cell 2-3)

In addition to not adding amorphous oxide in preparing solid electrolyte layer slurry, and 800 DEG C are warming up to instead of being warming up to 700 DEG C with the rate of heat addition of 400 DEG C/h to be sintered outside by the rate of heat addition with 400 DEG C/h, prepares comparative cell 2-3 according to mode identical with battery 2-1.It is assumed that green part only by Li_1.3Al_0.3Ti_1.7(PO₄)₃In the case where composition, the filling rate for being sintered green part is 55%.

(battery 2-6)

Except through with the rate of heat addition of 400 DEG C/h be warming up to 900 DEG C replace being warming up to the rate of heat addition of 400 DEG C/h 800 DEG C it is outer to be sintered, prepare battery 2-6 according to mode identical with comparative cell 2-3.It is assumed that green part only by Li_1.3Al_0.3Ti_1.7(PO₄)₃In the case where composition, the filling rate for being sintered green part is 83%.

(battery 2-7)

Except through with the rate of heat addition of 400 DEG C/h be warming up to 1000 DEG C replace being warming up to the rate of heat addition of 400 DEG C/h 800 DEG C it is outer to be sintered, prepare battery 2-7 according to mode identical with comparative cell 2-3.It is assumed that green part only by Li_1.3Al_0.3Ti_1.7(PO₄)₃In the case where composition, the filling rate for being sintered green part is 87%.

It is that in the range of 2.3V-1.0V, it is primary that battery 2-1 to 2-7 and comparative cell 2-1 to 2-3 is charged and discharged with the current value of 10 μ A in -50 DEG C of atmosphere and 25 DEG C of environment temperature in dew point.Table 12 shows resulting discharge capacity.In addition, measuring them in the impedance of 1kHz after the charge/discharge of battery.Table 12 shows result.

Table 12

	Amorphous oxide additive amount (weight %)	Maximum sintering temperature (DEG C)	Filling rate (%)	Discharge capacity (μ Ah)	Impedance (Ω)
	Amorphous oxide additive amount (weight %)	Maximum sintering temperature (DEG C)	Filling rate (%)	Discharge capacity (μ Ah)	Impedance (Ω)	Battery 2-1	3	700	73	9.2	2010
Battery 2-2	3	800	93	10.2	389	Battery 2-1	3	700	73	9.2	2010
Battery 2-2	3	800	93	10.2	389	Battery 2-3	3	900	95	9.7	403
Battery 2-4	3	1000	95	8.6	1900	Battery 2-3	3	900	95	9.7	403
Battery 2-4	3	1000	95	8.6	1900	Battery 2-5	3	800	93	10.3	363
Comparative cell 2-1	3	600	57	0	90300	Battery 2-5	3	800	93	10.3	363
Comparative cell 2-1	3	600	57	0	90300	Comparative cell 2-2	3	1100	93	0	It is undetectable
Comparative cell 2-3	It is not added with	800	55	0	103000	Comparative cell 2-2	3	1100	93	0	It is undetectable
Comparative cell 2-3	It is not added with	800	55	0	103000	Battery 2-6	It is not added with	900	83	10.1	3010
Battery 2-7	It is not added with	1000	87	8.6	2700	Battery 2-6	It is not added with	900	83	10.1	3010

In comparative cell 2-1 into 2-3, their discharge capacity is 0.In addition, their impedance is very high in comparative cell 2-1 into 2-3.This may be because the sintering of solid electrolyte does not carry out and therefore lithium ion conductivity is very small.Especially in the case where comparative cell 2-2, the impedance after charge/discharge (is not less than 10 beyond measurement range⁷Ω).This may be because solid electrolyte cannot bear high temperature and be denaturalized, so that lithium ion conductivity is lost.

On the other hand, battery 2-1 to 2-5 of the invention shows relatively good discharge capacity and low impedance.

In addition, battery 2-1 to 2-4 with comparative cell 2-1 to showing that charge/discharge is possible when sintering temperature is 700 DEG C or higher and 1000 DEG C or lower compared between 2-2, and the temperature range is preferred.

In addition, battery 2-1 to 2-4 and comparative cell 2-3 and battery 2-6 leads to low impedance and better battery to the obvious addition for showing sintering aid between 2-7.

Embodiment 2-2

Next, checking the additive amount of sintering aid.

(battery 2-8)

Except through with 99.9: 0.1 weight ratio hybrid solid electrolyte Li_1.3Al_0.3Ti_1.7(PO₄)₃With 72 weight %SiO of amorphous oxide₂- 1 weight %Al₂O₃- 20 weight %Na₂O-3 weight %MgO-4 weight %CaO is prepared outside solid electrolyte slurry, according to mode identical with battery 2-2 (sintering temperature: 800 DEG C) prepares battery 2-8.It is assumed that the green part only by Li_1.3Al_0.3Ti_1.7(PO₄)₃In the case where composition, the filling rate for being sintered green part is 72%.

(battery 2-9)

Except through with 99: 1 weight ratio hybrid solid electrolyte Li_1.3Al_0.3Ti_1.7(PO₄)₃With 72 weight %SiO of amorphous oxide₂- 1 weight %Al₂O₃- 20 weight %Na₂O-3 weight %MgO-4 weight %CaO is prepared outside solid electrolyte slurry, according to mode identical with battery 2-2 (sintering temperature: 800 DEG C) prepares battery 2-9.It is assumed that the green part only by Li_1.3Al_0.3Ti_1.7(PO₄)₃In the case where composition, the filling rate for being sintered green part is 89%.

(battery 2-10)

Except through with 95: 5 weight ratio hybrid solid electrolyte Li_1.3Al_0.3Ti_1.7(PO₄)₃With 72 weight %SiO of amorphous oxide₂- 1 weight %Al₂O₃- 20 weight %Na₂O-3 weight %MgO-4 weight %CaO is prepared outside solid electrolyte slurry, according to mode identical with battery 2-2 (sintering temperature: 800 DEG C) prepares battery 2-10.It is assumed that the green part only by Li_1.3Al_0.3Ti_1.7(PO₄)₃In the case where composition, the filling rate for being sintered green part is 94%.

(battery 2-11)

Except through with 90: 10 weight ratio hybrid solid electrolyte Li_1.3Al_0.3Ti_1.7(PO₄)₃With 72 weight %SiO of amorphous oxide₂- 1 weight %Al₂O₃- 20 weight %Na₂O-3 weight %MgO-4 weight %CaO is prepared outside solid electrolyte slurry, according to mode identical with battery 2-2 (sintering temperature: 800 DEG C) prepares battery 2-11.It is assumed that the green part only by Li_1.3Al_0.3Ti_1.7(PO₄)₃In the case where composition, the filling rate for being sintered green part is 94%.

(comparative cell 2-4)

Except through with 99.95: 0.05 weight ratio hybrid solid electrolyte Li_1.3Al_0.3Ti_1.7(PO₄)₃With 72 weight %SiO of amorphous oxide₂- 1 weight %Al₂O₃- 20 weight %Na₂O-3 weight %MgO-4 weight %CaO is prepared outside solid electrolyte slurry, according to mode identical with battery 2-2 (sintering temperature: 800 DEG C) prepares comparative cell 2-4.It is assumed that the green part only by Li_1.3Al_0.3Ti_1.7(PO₄)₃In the case where composition, the filling rate for being sintered green part is 57%.

(battery 2-12)

Except through with 85: 15 weight ratio hybrid solid electrolyte Li_1.3Al_0.3Ti_1.7(PO₄)₃With 72 weight %SiO of amorphous oxide₂- 1 weight %Al₂O₃- 20 weight %Na₂O-3 weight %MgO-4 weight %CaO is prepared outside solid electrolyte slurry, according to mode identical with battery 2-2 (sintering temperature: 800 DEG C) prepares battery 2-12.It is assumed that the green part only by Li_1.3Al_0.3Ti_1.7(PO₄)₃In the case where composition, the filling rate for being sintered green part is 93%.

Using the battery 2-8 to 2-12 and comparative cell 2-4 so prepared, their discharge capacity and impedance at 1 khz are measured according to method identical with previous embodiment 2-1.Table 13 is shown as a result, as with reference to the result for also showing battery 2-2 and comparative cell 2-3.

Table 13

	Amorphous oxide additive amount (weight %)	Maximum sintering temperature (DEG C)	Filling rate (%)	Discharge capacity (μ Ah)	Impedance (Ω)
	Amorphous oxide additive amount (weight %)	Maximum sintering temperature (DEG C)	Filling rate (%)	Discharge capacity (μ Ah)	Impedance (Ω)	Battery 2-2	3	800	93	10.2	389
Battery 2-8	0.1	800	72	4.8	9300	Battery 2-2	3	800	93	10.2	389
Battery 2-8	0.1	800	72	4.8	9300	Battery 2-9	1	800	89	8.9	583
Battery 2-10	5	800	94	9.3	440	Battery 2-9	1	800	89	8.9	583
Battery 2-10	5	800	94	9.3	440	Battery 2-11	10	800	94	6.0	6200
Comparative cell 2-3	It is not added with	800	55	0	103000	Battery 2-11	10	800	94	6.0	6200
Comparative cell 2-3	It is not added with	800	55	0	103000	Comparative cell 2-4	0.05	800	57	0	71000
Battery 2-12	15	800	93	2.7	10100	Comparative cell 2-4	0.05	800	57	0	71000

The discharge capacity of comparative cell 2-4 is 0.Probably due to the amount of sintering aid is too small for being sintered, so comparative cell 2-4 shows big impedance.On the other hand, probably due to the ionic conductivity reduction of excessive addition and therefore solid electrolyte layer, battery 2-12 show big impedance.

Above the result shows that sintering aid preferably takes up the 0.1-10 weight % of adding layers.

Embodiment 2-3

Next, checking the type of the sintering aid added to solid electrolyte layer and the softening point of sintering aid.

(battery 2-13)

In addition to using by 80 weight %SiO₂- 14 weight %B₂O₃- 2 weight %Al₂O₃- 3.6 weight %Na₂O-0.4 weight %K₂The amorphous oxide that O is represented replaces 72 weight %SiO₂- 1 weight %Al₂O₃- 20 weight %Na₂Outside O-3 weight %MgO-4 weight %CaO, battery 2-10 is prepared according to mode identical with battery 2-2.It is assumed that the green part only by Li_1.3Al_0.3Ti_1.7(PO₄)₃In the case where composition, the filling rate for being sintered green part is about 91%.

(comparative cell 2-5)

In addition to using Al₂O₃Powder replaces 72 weight %SiO₂- 1 weight %Al₂O₃- 20 weight %Na₂Outside O-3 weight %MgO-4 weight %CaO, comparative cell 2-5 is prepared according to mode identical with battery 2-2.It is assumed that the green part only by Li_1.3Al_0.3Ti_1.7(PO₄)₃In the case where composition, the filling rate for being sintered green part is about 55%.

(comparative cell 2-6)

It is 600 DEG C of 72 weight %SiO in addition to using softening point₂- 1 weight %Al₂O₃- 14 weight %Na₂O-3 weight %MgO-10 weight %CaO powder replaces 72 weight %SiO₂- 1 weight %Al₂O₃- 20 weight %Na₂Outside O-3 weight %MgO-4 weight %CaO, comparative cell 2-6 compared with being prepared according to mode identical with battery 2-2.It is assumed that the green part only by Li_1.3Al_0.3Ti_1.7(PO₄)₃In the case where composition, the filling rate for being sintered green part is about 97%.

(comparative cell 2-7)

It is 1020 DEG C of 62 weight %SiO in addition to using softening point₂- 15 weight %Al₂O₃- 8 weight %CaO-15 weight %BaO powder replace 72 weight %SiO₂- 1 weight %Al₂O₃- 20 weight %Na₂Outside O-3 weight %MgO-4 weight %CaO, comparative cell 2-7 compared with being prepared according to mode identical with battery 2-2.It is assumed that the green part only by Li_1.3Al_0.3Ti_1.7(PO₄)₃In the case where composition, the filling rate for being sintered green part is about 58%.

Using the battery 2-13 and comparative cell 2-5 to 2-7 so prepared, their discharge capacity and impedance at 1 khz are measured according to method identical with previous embodiment 2-1.Table 14 is shown as a result, as with reference to the result for also showing battery 2-2.

Table 14

	Amorphous oxide additive amount (weight %)	Amorphous oxide softening point (DEG C)	Maximum sintering temperature (DEG C)	Filling rate (%)	Initial discharge capacity (μ Ah)	Impedance (Ω)
	Amorphous oxide additive amount (weight %)	Amorphous oxide softening point (DEG C)	Maximum sintering temperature (DEG C)	Filling rate (%)	Initial discharge capacity (μ Ah)	Impedance (Ω)	Battery 2-2	3	750	800	93	10.3	389
Battery 2-10	3	915	800	91	10.0	403	Battery 2-2	3	750	800	93	10.3	389
Battery 2-10	3	915	800	91	10.0	403	Comparative cell 2-5	3	660	800	55	0	It is undetectable
Comparative cell 2-6	3	600	800	97	0	It is undetectable	Comparative cell 2-5	3	660	800	55	0	It is undetectable
Comparative cell 2-6	3	600	800	97	0	It is undetectable	Comparative cell 2-7	3	1020	800	58	0	98000

The discharge capacity of battery 2-13 and impedance are equal with the discharge capacity of battery 2-2 and impedance.

On the other hand, common sintering aid Al is being used₂O₃Comparing embodiment 2-5 in the case where, discharge capacity is 0.This may be because the sintering of laminated body does not carry out in sintering.I.e., it is believed that using Al₂O₃System in, Al₂O₃With solid electrolyte Li_1.3Al_0.3Ti_1.7(PO₄)₃Reaction, generates impurity phase in solid electrolyte layer, bad so as to cause being sintered.

In addition, discharge capacity is also 0 in the case where being added to the comparative cell 2-6 for the amorphous oxide that softening point is 600 DEG C.This may be because the diffusion of active material and solid electrolyte is unable to charge/discharge as sintering reaction carries out together.

In the case where being added to the comparative cell 2-7 for the amorphous oxide that softening point is 1020 DEG C, discharge capacity is also 0.This may be to be unable to acceleration of sintering because the softening point of additive is too high.

The above results show that by adding softening point at least one anode active material layer, solid electrolyte layer and anode active material layer be 700 DEG C or higher and 950 DEG C or lower amorphous oxide, can produce the all-solid-state battery with good charge/discharge capabilities.

Embodiment 2-4

Other than anode active material layer is not provided and maximum sintering temperature is changed into 800 DEG C, the laminated body comprising anode active material layer and solid electrolyte layer is prepared according to mode identical with comparative cell 2-3, comparative cell 2-4, battery 2-8, battery 2-9, battery 2-2, battery 2-10, the preparation method of battery 2-11 and battery 2-12.These laminated bodies are referred to as and compares laminated body 2-3, compare laminated body 2-4, laminated body 2-8, laminated body 2-9, laminated body 2-2, laminated body 2-10, laminated body 2-11 and laminated body 2-12.Measure the warpage of these laminated bodies.Warpage used herein refers to vertical range of the laminated body away from the plate being placed in the upward predetermined tablet of its anode active material layer, the specifically vertical range away from laminated body anode active material layer upper surface.It should be understood that the green part of these laminated bodies is with about 500 μm of thickness and the size of 7mm × 7mm before being sintered.

In addition, table 15 also shows the amount and maximum sintering temperature for being added to and forming the amorphous oxide of solid electrolyte layer in green sheet.

Table 15

	Amorphous oxide additive amount (weight %)	Maximum sintering temperature (DEG C)	Warpage (mm)
	Amorphous oxide additive amount (weight %)	Maximum sintering temperature (DEG C)	Warpage (mm)	Compare laminated body 2-3	It is not added with	800	2.2
Compare laminated body 2-4	0.05	800	2.0	Compare laminated body 2-3	It is not added with	800	2.2
Compare laminated body 2-4	0.05	800	2.0	Laminated body 2-8	0.1	800	1.3
Laminated body 2-9	1	800	0.8	Laminated body 2-8	0.1	800	1.3
Laminated body 2-9	1	800	0.8	Laminated body 2-2	3	800	0.6
Laminated body 2-10	5	800	0.6	Laminated body 2-2	3	800	0.6
Laminated body 2-10	5	800	0.6	Laminated body 2-11	10	800	0.6
Laminated body 2-12	15	800	0.6	Laminated body 2-11	10	800	0.6

Table 15 shows that the warpage of laminated body is reduced with the increase of amorphous object amount.Therefore, in order to inhibit warpage, the preferably additive amount of amorphous oxide is 0.1 weight % or higher.

Embodiment 3-1

(battery 3-1)

In addition to using palladium glue to replace gold size in the preparation of positive electrode collector green sheet and negative electrode collector green sheet, palladium content is changed into 25 weight % of the glue, the thickness of positive electrode collector green sheet and negative electrode collector green sheet is changed into 10 μm, and by green part be sintered in maximum temperature from 900 change into 950 DEG C it is outer, prepare battery 3-1 according to mode identical with battery 21.

The sintered body that the green part as obtained by sintering obtains has width, the depth of about 1.6mm and the height of about 0.45mm of about 3.2mm.According to identical mode in preceding embodiment 1-2, it is assumed that the sintered body only by Li_1.3Al_0.3Ti_1.7(PO₄)₃The lower filling rate for determining sintered body of composition.As a result, filling rate is about 85%.

With the polishing section of SEM observation sintered body.As a result, anode active material layer and anode active material layer are respectively provided with about 1 μm of thickness and about 2 μm of thickness.The positive electrode collector layer being arranged in anode active material layer and the negative electrode collector layer being arranged in anode active material layer all have about 4 μm of thickness.

For example, determining the porosity of positive electrode collector layer and negative electrode collector layer as follows.

Obtain the weight of palladium in per unit area positive electrode collector green sheet or negative electrode collector green sheet.When sintering, collector green sheet is shunk.The weight of per unit area palladium is calculated from the weight of the palladium of per unit area green sheet after contraction.Then, with the apparent thickness of the collector of SEM observation sintering.In this way, the volume of current collector layer and the amount of palladium wherein included can be determined.Using these values, the porosity of current collector layer can be determined.In the following embodiments, porosity is determined in this manner.

As a result, the porosity of every layer of positive electrode collector layer and negative electrode collector layer is 50%.

(battery 3-2)

Other than the content of palladium in palladium glue is changed into 65 weight %, battery 3-2 is prepared according to mode identical with battery 3-1.After sintering, positive electrode collector layer and negative electrode collector layer have 20% porosity.

(battery 3-3)

Other than the content of palladium in palladium glue is changed into 20 weight %, battery 3-3 is prepared according to mode identical with battery 3-1.After sintering, positive electrode collector layer and negative electrode collector layer have 60% porosity.

(battery 3-4)

Other than the content of palladium in palladium glue is changed into 70 weight %, comparative cell 3-1 is prepared according to mode identical with battery 3-1.After sintering, positive electrode collector layer and negative electrode collector layer have 15% porosity.

(battery 3-5)

Other than the content of palladium in palladium glue is changed into 10 weight %, comparative cell 3-2 is prepared according to mode identical with battery 3-1.After sintering, positive electrode collector layer and negative electrode collector layer have 70% porosity.

It is that it is primary that 10 battery units (cell) are charged and discharged with the constant current value of 10 μ A in -50 DEG C of atmosphere and 25 DEG C of environment temperature in dew point for battery 3-1 to 3-5.Upper blanking voltage is 2.2V and lower blanking voltage is 1.0V.

Table 16 shows the initial discharge capacity for each battery unit that can be charged and discharged without rupture and with the element number of fault of construction.

Table 16

	Collector porosity (%)	Discharge capacity (μ Ah)	Element number with fault of construction
	Collector porosity (%)	Discharge capacity (μ Ah)	Element number with fault of construction	Battery 3-1	50	5.4	1
Battery 3-2	20	5.7	1	Battery 3-1	50	5.4	1
Battery 3-2	20	5.7	1	Battery 3-3	60	5.1	0
Battery 3-4	15	5.6	4	Battery 3-3	60	5.1	0
Battery 3-4	15	5.6	4	Battery 3-5	70	3.5	0

Battery 3-1 to 3-3 can be charged and discharged.Battery 3-4 and 3-5 can be also charged and discharged.The initial discharge capacity of battery 3-5 is less than other batteries.It should be understood that battery capacity can be improved by the quantity for increasing layer laminate body.

In battery 3-4, four units show rupture or leafing.These units cannot provide enough discharge capacities.

In battery 3-1 into 3-3, collector porosity is 20-60%, and it is believed that this porosity has the function of absorbing active material volume change due to caused by charge/discharge.In comparison, in the battery 3-4 that collector porosity is 15%, probably due to the volume change of active material caused by cannot absorbing due to absorbing and releasing lithium ion, the quantity for rupturing battery increases.

In addition, there is no cell fractures, but capacity drops to about 60-70% in the battery 3-5 that collector porosity is 70%.This capacity decline may be due to caused by the deterioration of collector collection properties of flow.Therefore, the porosity of positive electrode collector layer and negative electrode collector layer is preferably 20-60%.

Above the result shows that, when setting 20-60% for current collector layer porosity, it can inhibit the rupture derived from active material expansion and the leafing and stratotype all-solid-state battery shunk during charge/discharge, and therefore generate the stratotype all solid lithium secondary battery of specific height reliability.

Embodiment 3-2

In the present embodiment, in the case where using other active materials, influence of the collector porosity to discharge capacity and fault of construction is checked.

(battery 3-6)

In addition to using LiMnPO₄LiCoPO is replaced as positive electrode active materials₄Outside, battery 3-6 is prepared according to mode identical with battery 3-1.

(battery 3-7)

In addition to using LiFePO₄LiCoPO is replaced as positive electrode active materials₄, including CO₂And H₂And green part is roasted in the atmosphere gas with predetermined partial pressure of oxygen, green part is made to maintain 5 hours to decompose the binder for including in green part, and CO in atmosphere gas at 600 DEG C₂And H₂Between mixing ratio be 10³: outside 1, battery 3-7 is prepared according to mode identical with battery 3-1.

(battery 3-8)

In addition to using LiMn_0.5Fe_0.5PO₄LiCoPO is replaced as positive electrode active materials₄, including CO₂And H₂And green part is roasted in the atmosphere gas with predetermined partial pressure of oxygen, green part is made to maintain 5 hours to decompose the binder for including in green part, and CO in atmosphere gas at 600 DEG C₂And H₂Between mixing ratio be 10³: outside 1, battery 3-8 is prepared according to mode identical with battery 3-1.

(battery 3-9)

In addition to using FePO₄Li is replaced as negative electrode active material₃Fe₂(PO₄)₃Outside, battery 3-9 is prepared according to mode identical with battery 3-1.

(battery 3-10)

In addition to using LiFeP₂O₇Li is replaced as negative electrode active material₃Fe₂(PO₄)₃Outside, battery 3-10 is prepared according to mode identical with battery 3-1.

(battery 3-11)

In addition to using Li_1.3Al_0.3Ti_1.7(PO₄)₃Instead of Li₃Fe₂(PO₄)₃Outside, battery 3-11 is prepared according to mode identical with battery 3-1.

(battery 3-12)

Other than the content of palladium in palladium glue is changed into 75 weight %, battery 3-12 is prepared according to mode identical with battery 3-6.After sintering, positive electrode collector layer and negative electrode collector layer have 10% porosity.

(battery 3-13)

Other than the content of palladium in palladium glue is changed into 75 weight %, battery 3-13 is prepared according to mode identical with battery 3-7.After sintering, positive electrode collector layer and negative electrode collector layer have 10% porosity.

(battery 3-14)

Other than the content of palladium in palladium glue is changed into 75 weight %, battery 3-14 is prepared according to mode identical with battery 3-8.After sintering, positive electrode collector layer and negative electrode collector layer have 10% porosity.

(battery 3-15)

Other than the content of palladium in palladium glue is changed into 75 weight %, battery 3-15 is prepared according to mode identical with battery 3-9.After sintering, positive electrode collector layer and negative electrode collector layer have 10% porosity.

(battery 3-16)

Other than the content of palladium in palladium glue is changed into 75 weight %, battery 3-16 is prepared according to mode identical with battery 3-10.After sintering, positive electrode collector layer and negative electrode collector layer have 10% porosity.

(battery 3-17)

Other than the content of palladium in palladium glue is changed into 75 weight %, battery 3-17 is prepared according to mode identical with battery 3-11.After sintering, positive electrode collector layer and negative electrode collector layer have 10% porosity.

It is that it is primary that 10 units are charged and discharged with the current value of 10 μ A in -50 DEG C of atmosphere and 25 DEG C of environment temperature in dew point for each battery of battery 3-6 to 3-17.Table 17 shows the upper blanking voltage and lower blanking voltage of battery.Table 17 also shows the initial discharge capacity for each battery unit that can be charged and discharged without rupture.In addition, table 18 shows the quantity of the unit with fault of construction.

Table 17

	Initial discharge capacity (μ Ah)	Upper blanking voltage (V)	Lower blanking voltage (V)
	Initial discharge capacity (μ Ah)	Upper blanking voltage (V)	Lower blanking voltage (V)	Battery 3-6	6.5	2.0	0.5
Battery 3-7	6.6	1.0	0.3	Battery 3-6	6.5	2.0	0.5
Battery 3-7	6.6	1.0	0.3	Battery 3-8	7.1	2.0	0.3
Battery 3-9	5.6	2.0	0.6	Battery 3-8	7.1	2.0	0.3
Battery 3-9	5.6	2.0	0.6	Battery 3-10	5.6	2.1	0.9
Battery 3-11	5.9	2.5	1.0	Battery 3-10	5.6	2.1	0.9
Battery 3-11	5.9	2.5	1.0	Battery 3-12	6.5	2.0	0.5
Battery 3-13	6.6	1.0	0.3	Battery 3-12	6.5	2.0	0.5
Battery 3-13	6.6	1.0	0.3	Battery 3-14	7.1	2.0	0.3
Battery 3-15	5.6	2.0	0.6	Battery 3-14	7.1	2.0	0.3
Battery 3-15	5.6	2.0	0.6	Battery 3-16	5.6	2.1	0.9
Battery 3-17	5.9	2.5	1.0	Battery 3-16	5.6	2.1	0.9

Table 18

	Unit number with fault of construction		Unit number with fault of construction
	Unit number with fault of construction		Unit number with fault of construction	Battery 3-6	0	Battery 3-12	1
Battery 3-7	0	Battery 3-13	3	Battery 3-6	0	Battery 3-12	1
Battery 3-7	0	Battery 3-13	3	Battery 3-8	0	Battery 3-14	3
Battery 3-9	0	Battery 3-15	2	Battery 3-8	0	Battery 3-14	3
Battery 3-9	0	Battery 3-15	2	Battery 3-10	0	Battery 3-16	2
Battery 3-11	1	Battery 3-17	3	Battery 3-10	0	Battery 3-16	2

Battery 3-6 to 3-11 can be charged and discharged.Battery 3-12 to 3-17 can be also charged and discharged, and their initial discharge capacity is almost identical as battery 3-6 to 3-11.

But some units of battery 3-12 to 3-17 show rupture or leafing.These units cannot provide enough discharge capacities.

On the other hand, in the case where battery 3-6 to 3-11, the unit number with fault of construction is few compared with battery 3-12 to 3-17.This shows that when setting 20-60% for the porosity of current collector layer, current collector layer is used as buffer layer, and current collector layer can all absorb active material volume change due to caused by charge/discharge.

Embodiment 3-3

In the present embodiment, using the collector comprising ordinary metallic material.

(battery 3-18)

Use LiCoPO₄As positive electrode active materials, and use Li_1.3Al_0.3Ti_1.7(PO₄)₃As solid electrolyte.This solid electrolyte layer is used as negative electrode active material.

Use copper as the metal material for including in positive electrode collector layer and negative electrode collector layer.The content of copper in current collector material paste is 30 weight % of paste.

Including CO₂And H₂And green part is sintered in the atmosphere gas with predetermined partial pressure of oxygen.In the atmosphere gas, CO₂And H₂Between mixing ratio be 10³∶1。

In addition, during being sintered green part, 600 DEG C at a temperature of decompose binder.

In addition to this, battery 3-18 is prepared according to mode identical with battery 3-1.After baking, positive electrode collector layer and negative electrode collector layer have 50% porosity.

(battery 3-19)

In addition to using cobalt as the metal material for including in positive electrode collector layer and negative electrode collector layer, by CO in the atmosphere gas for being used to roast green part₂And H₂Between volume ratio change into 10: 1, and decomposed outside the binder for including in green part by heating 72 hours at 600 DEG C, prepare battery 3-19 according to mode identical with battery 3-18.After baking, positive electrode collector layer and negative electrode collector layer have 50% porosity.

(battery 3-20)

In addition to using nickel as the metal material for including in positive electrode collector layer and negative electrode collector layer, by CO in the atmosphere gas for being used to roast green part₂And H₂Between volume ratio change into 40: 1, and decomposed outside the binder for including in green part by heating 48 hours at 600 DEG C, prepare battery 3-20 according to mode identical with battery 3-18.After baking, positive electrode collector layer and negative electrode collector layer have 50% porosity.

(battery 3-21)

In addition to using stainless steel as the metal material for including in positive electrode collector layer and negative electrode collector layer, and the maximum temperature for changing roasting green part is 1000 DEG C outer, prepares battery 3-21 according to mode identical with battery 3-18.After baking, positive electrode collector layer and negative electrode collector layer have 50% porosity.

(comparative cell 3-1)

In addition to using titanium as the metal material for including in positive electrode collector layer and negative electrode collector layer, and the maximum temperature for changing roasting green part is 900 DEG C outer, prepares comparative cell 3-1 according to mode identical with battery 3-18.After baking, positive electrode collector layer and negative electrode collector layer have 50% porosity.

For each battery of battery 3-18 to 3-21 and comparative cell 3-1,10 units of constant-current charge and electric discharge under condition identical with battery 3-11 (the upper blanking voltage of 2.5V and 1.0V under blanking voltage).Table 19 shows the quantity of the initial discharge capacity and the unit with fault of construction that can be charged and discharged without causing each battery unit of defect.

Table 19

	Initial discharge capacity (μ Ah)	Unit number with fault of construction
	Initial discharge capacity (μ Ah)	Unit number with fault of construction	Battery 3-18	5.4	1
Battery 3-19	5.5	0	Battery 3-18	5.4	1
Battery 3-19	5.5	0	Battery 3-20	5.2	1
Battery 3-21	4.8	0	Battery 3-20	5.2	1
Battery 3-21	4.8	0	Comparative cell 3-1	0	0

Battery 3-18, the result shows that even when using common metal (base metal) as current collector material, can also prevent the oxidation of current collector material by roasting green part under the partial pressure of oxygen of control roasting atmosphere gas to 3-21's.Therefore, use common metal being capable of charge/discharge as the solid state battery of current collector material.

In comparative cell 3-1, no unit shows rupture and/or leafing.But comparative cell 3-1 itself is unable to charge/discharge.This may be because the titanium itself for constituting current collector layer is oxidized and therefore current collector layer cannot maintain the ability of its collected current.Green part can be roasted in the not oxidized atmosphere of titanium, but when using this atmosphere, cannot decompose binder.

The above results show that the metal material of resistance to oxidation to a certain extent can be used as current collector material by the partial pressure of oxygen for controlling atmosphere gas.

Embodiment 3-5

In the present embodiment, the porosity that positive electrode collector layer and negative electrode collector layer is arranged is 10%.

(battery 3-22)

Other than the content of copper in the copper glue for being used to form positive electrode collector layer and negative electrode collector layer to be changed into 70 weight % of glue, battery 3-22 is prepared according to mode identical with battery 3-18.Positive electrode collector layer and negative electrode collector layer have 10% porosity.

(battery 3-23)

Other than the content of cobalt in the cobalt glue for being used to form positive electrode collector layer and negative electrode collector layer to be changed into 70 weight % of glue, battery 3-23 is prepared according to mode identical with battery 3-19.Positive electrode collector layer and negative electrode collector layer have 10% porosity.

(battery 3-24)

Other than the content of nickel in the nickel glue for being used to form positive electrode collector layer and negative electrode collector layer to be changed into 70 weight % of glue, battery 3-24 is prepared according to mode identical with battery 3-20.Positive electrode collector layer and negative electrode collector layer have 10% porosity.

(battery 3-25)

Other than the content of stainless steel in the stainless steel glue for being used to form positive electrode collector layer and negative electrode collector layer to be changed into 70 weight % of glue, battery 3-25 is prepared according to mode identical with battery 3-21.Positive electrode collector layer and negative electrode collector layer have 10% porosity.

For each battery of the battery 3-22 into 3-25,10 units of constant-current charge and electric discharge under condition identical with battery 3-18 (the upper blanking voltage of 2.5V and 1.0V under blanking voltage).Table 20 shows the quantity of the initial discharge capacity and the unit with fault of construction that can be charged and discharged without causing each battery unit of defect.

Table 20

	Initial discharge capacity (μ Ah)	Unit number with fault of construction
	Initial discharge capacity (μ Ah)	Unit number with fault of construction	Battery 3-22	5.4	3
Battery 3-23	5.5	5	Battery 3-22	5.4	3
Battery 3-23	5.5	5	Battery 3-24	5.2	4
Battery 3-25	4.8	5	Battery 3-24	5.2	4

The initial discharge capacity of battery 3-22 to 2-25 is equal with the initial discharge capacity of battery 3-18 to 3-21.In battery 3-22 into 3-25, because the porosity of positive electrode collector layer and negative electrode collector layer is 10%, this current collector layer is difficult to absorb the volume change of active material during charge/discharge.This may be why to increase in unit number of the battery 3-22 into 3-25 with fault of construction.

As described above, the current collector layer of the ordinary metallic material comprising resistance to oxidation to a certain extent can also be used other than noble metal.In addition, leafing and/or rupture caused by changing derived from active material volume during charge/discharge can be inhibited by the way that porosity is adjusted to 20-60%.It is, therefore, possible to provide highly reliable all solid lithium secondary battery.

Industrial applicability

Laminated body of the invention has the interface of electro-chemical activity and low internal resistance between the solid electrolyte layer for being densified and being crystallized due to heat treatment and active material layer, active material and solid electrolyte.Such as all solid lithium secondary battery with high capacity and excellent high-rate characteristics can be provided using this laminated body.

Claims

1. a kind of laminated body for all solid lithium secondary battery, the laminated body includes active material layer and the solid electrolyte layer by being sintered and the active material layer bonds,

Wherein the active material layer includes to be capable of the first substance of the crystalline form of absorption and desorption lithium ion,

The solid electrolyte layer includes second of substance of crystalline form with lithium-ion-conducting, and

The X-ray diffraction of the laminated body is analysis shows without other component other than the constituent component of the constituent component of the active material layer and the solid electrolyte layer.

2. the laminated body according to claim 1 for all solid lithium secondary battery, wherein the first described substance includes to be capable of the first phosphate cpd of the crystalline form of absorption and desorption lithium ion, and second of substance includes second of phosphate cpd of crystalline form with lithium-ion-conducting.

3. the laminated body according to claim 1 for all solid lithium secondary battery, the wherein at least described solid electrolyte layer has the filling rate higher than 70%.

4. the laminated body according to claim 1 for all solid lithium secondary battery, wherein at least one layer of in the active material layer and the solid electrolyte layer includes amorphous oxide.

5. the laminated body according to claim 4 for all solid lithium secondary battery, wherein at least one layer of amorphous oxide comprising 0.1-10 weight % in the active material layer and the solid electrolyte layer.

6. the laminated body according to claim 4 for all solid lithium secondary battery, wherein the amorphous oxide has 700 DEG C or higher and 950 DEG C or lower softening point.

7. the laminated body according to claim 2 for all solid lithium secondary battery, wherein the first described phosphate cpd is represented by following general formula:

LiMPO₄

Wherein M is selected from least one of Mn, Fe, Co and Ni.

8. the laminated body according to claim 2 for all solid lithium secondary battery, wherein second of phosphate cpd is represented by following general formula:

Li_1+xM^III _xTi^IV _2-X(PO₄)₃

9. a kind of all solid lithium secondary battery including laminated body, the laminated body includes combining comprising anode active material layer and at least one by being sintered the solid electrolyte layer bonded with the anode active material layer,

Wherein the anode active material layer includes to be capable of the first substance of the crystalline form of absorption and desorption lithium ion,

10. all solid lithium secondary battery according to claim 9, wherein the first described substance is to be capable of the first phosphate cpd of the crystalline form of absorption and desorption lithium ion, and second of substance is second of phosphate cpd of crystalline form with lithium-ion-conducting.

11. all solid lithium secondary battery according to claim 9, wherein at least one combination has the anode active material layer in face of the anode active material layer, and the solid electrolyte layer is inserted in therebetween, the solid electrolyte layer and the anode active material layer bond, and the anode active material layer includes to be capable of the third phosphate cpd of the crystalline form of absorption and desorption lithium ion or the oxide containing Ti.

12. all solid lithium secondary battery according to claim 9, wherein the solid electrolyte layer has the filling rate higher than 70%.

13. all solid lithium secondary battery according to claim 10, wherein the first described phosphate cpd is represented by following general formula:

LiMPO₄

Wherein M is selected from least one of Mn, Fe, Co and Ni.

14. all solid lithium secondary battery according to claim 10, wherein second of phosphate cpd is represented by following general formula:

Li_1+xM^III _xTi^IV _2-X(PO₄)₃

15. all solid lithium secondary battery according to claim 11, wherein the third described phosphate cpd is selected from FePO₄、Li₃Fe₂(PO₄)₃And LiFeP₂O₇At least one of.

16. all solid lithium secondary battery according to claim 10, wherein second of phosphate cpd includes Li_1+xM^III _xTi^IV _2-X(PO₄)₃, wherein M^IIIIt is selected from least one of Al, Y, Ga, In and La metal ion, and 0≤x≤0.6, and the solid electrolyte layer is used as anode active material layer.

17. solid lithium battery according to claim 9, wherein at least one layer of in the anode active material layer and the solid electrolyte layer includes amorphous oxide.

18. all solid lithium secondary battery according to claim 17, wherein the amorphous oxide constitutes the 0.1-10 weight % of the layer comprising it.

19. all solid lithium secondary battery according to claim 17, wherein the amorphous oxide has 700 DEG C or higher and 950 DEG C or lower softening point.

20. all solid lithium secondary battery according to claim 9, wherein at least one the anode active material layer and solid electrolyte layer include Li₄P₂O₇, and the solid electrolyte layer has 70% or more filling rate.

21. all solid lithium secondary battery according to claim 20, wherein Li₄P₂O₇Constitute the 0.1-10 weight % of the layer comprising it.

22. all solid lithium secondary battery according to claim 9, wherein not bonding the solid electrolyte layer with the face of anode active material layer bonding and lithium metal or collector, is inserted into the electrolyte layer of anti-reduction therebetween.

23. all solid lithium secondary battery according to claim 9, wherein at least one combination is clipped between positive electrode collector and negative electrode collector.

24. all solid lithium secondary battery according to claim 11, wherein the anode active material layer has positive electrode collector, and the anode active material layer has negative electrode collector.

25. all solid lithium secondary battery according to claim 24, wherein providing film collector at least one anode active material layer and anode active material layer.

26. all solid lithium secondary battery according to claim 25, wherein the positive electrode collector and the negative electrode collector at least one there is 20% or higher and 60% or lower porosity.

27. all solid lithium secondary battery according to claim 25, wherein the center portion on the active material layer thickness direction provides at least one the film positive electrode collector and the film cathode collector.

28. all solid lithium secondary battery according to claim 24 provides collector wherein running through at least one the anode active material layer and the anode active material layer in the form of three-dimensional network.

29. all solid lithium secondary battery according to claim 24, wherein with the opposite facing face in face of the anode active material layer contacted with the solid electrolyte layer and at least one the opposite facing face in face of the anode active material layer contacted with the solid electrolyte is upper provides collector.

30. all solid lithium secondary battery according to claim 24, wherein at least one combination includes two or more combinations, and the positive electrode collector and the negative electrode collector pass through the outer collector of anode respectively and the outer collector of cathode is connected in parallel.

31. all solid lithium secondary battery according to claim 24, wherein the positive electrode collector and the negative electrode collector include conductive material.

32. according to all solid lithium secondary battery of claim 31, wherein the conductive material includes selected from least one of stainless steel, silver, copper, nickel, cobalt, palladium, gold and platinum.

33. all solid lithium secondary battery according to claim 30, wherein the outer collector of the anode and the outer collector of the cathode include the mixture of metal and glass powder.

34. a kind of method for preparing the laminated body comprising active material layer and solid electrolyte layer, the described method comprises the following steps:

Disperse active material in the solvent comprising binder and plasticizer to form the slurry 1 for being used to form active material layer；

Dispersing solid electrolyte is in the solvent comprising binder and plasticizer to form the slurry 2 for being used to form solid electrolyte layer；

Active material green sheet is prepared using the slurry 1；

Solid electrolyte green sheet is prepared using the slurry 2；And

The active material green sheet and the solid electrolyte green sheet and application heat treatment is laminated to form laminated body,

Wherein the active material includes the first phosphate cpd for capableing of absorption and desorption lithium ion, and the solid electrolyte includes second of phosphate cpd with lithium-ion-conducting.

35. according to the method for the preparation laminated body of claim 34, wherein at least one the slurry 1 and the slurry 2 include amorphous oxide, and the heat treatment at 700 DEG C or higher and 1000 DEG C or is more lowly carried out.

36. according to the method for the preparation laminated body of claim 35, wherein the ratio of the total amount of the amorphous oxide described at least one slurry and the amorphous oxide and the active material or the solid electrolyte is 0.1 weight % to 10 weight %.

37. according to the method for the preparation laminated body of claim 35, wherein the amorphous oxide has 700 DEG C or higher and 950 DEG C or lower softening point.

38. a kind of method for preparing the laminated body comprising active material layer and solid electrolyte layer, the described method comprises the following steps:

Position activity material forms active material layer on substrate；

Deposition solid electrolyte is on the active material layer to form solid electrolyte layer；And

It is crystallized to the active material layer and solid electrolyte layer application heat treatment,

Wherein the active material include be capable of the first phosphate cpd of the crystalline form of absorption and desorption lithium ion, and

The solid electrolyte includes second of phosphate cpd of crystalline form with lithium-ion-conducting.

39. according to the method for the preparation laminated body of claim 38, wherein depositing the active material and the solid electrolyte over the substrate by sputtering.

40. a kind of method for preparing all solid lithium secondary battery, the described method comprises the following steps:

(a) disperse positive electrode active materials in the solvent comprising binder and plasticizer to form the slurry 1 for being used to form anode active material layer；

(b) in the solvent comprising binder and plasticizer dispersing solid electrolyte to form the slurry 2 for being used to form solid electrolyte layer；

(c) disperse negative electrode active material in the solvent comprising binder and plasticizer to form the slurry 3 for being used to form anode active material layer；

(d) positive electrode active materials green sheet is prepared using the slurry 1；

(e) solid electrolyte green sheet is prepared using the slurry 2；

(f) negative electrode active material green sheet is prepared using the slurry 3；

(g) the first green sheet group including following at least one combination is formed, the combination includes: the positive electrode active materials green sheet and the negative electrode active material green sheet of the solid electrolyte sheet and the clamping solid electrolyte sheet；And

(h) Xiang Suoshu the first green sheet group application heat treatment with formed include anode active material layer, solid electrolyte layer and anode active material layer at least one entire combination laminated body,

Wherein the positive electrode active materials include to be capable of the first phosphate cpd of the crystalline form of absorption and desorption lithium ion,

The solid electrolyte includes second of phosphate cpd with lithium-ion-conducting, and

The negative electrode active material includes the third phosphate cpd for capableing of absorption and desorption lithium ion or the oxide containing Ti.

41. according to the method for preparing all solid lithium secondary battery of claim 40, wherein at least one of the slurry 1, the slurry 2 and described slurry 3 include amorphous oxide.

42. according to the method for preparing all solid lithium secondary battery of claim 41, wherein at 700 DEG C or higher and 1000 DEG C or lower implementation is heat-treated in the step (h).

43. according to the method for preparing all solid lithium secondary battery of claim 40,

Wherein Li is added at least one of the slurry 1, the slurry 2 and described slurry 3₄P₂O₇, and in the step (h), at 700 DEG C or higher and 1000 DEG C or lower implementation is heat-treated.

44. according to the method for preparing all solid lithium secondary battery of claim 40,

Wherein in the step (g), the combination includes at least positive electrode active materials green sheet, at least negative electrode active material green sheet and solid electrolyte green sheet that prepare in the manner described above of two panels that prepare in the manner described above of two panels,

It is inserted into positive electrode collector between at least two panels positive electrode active materials green sheet, and is inserted into negative electrode collector between at least two panels negative electrode active material green sheet, and

In the different surface region of the laminated body, one end of the positive electrode collector and one end of the negative electrode collector are exposed.

45. according to the method for preparing all solid lithium secondary battery of claim 40,

Wherein in the step (a) and step (c), positive electrode collector material and negative electrode collector material are further mixed into respectively in the slurry 1 and the slurry 3, and

46. a kind of prepare all solid lithium secondary battery method comprising following steps:

(A) first group is formed, this first group includes the combination being made of anode active material layer, anode active material layer and the solid electrolyte layer being inserted between anode active material layer and anode active material layer；And

(B) it is heat-treated described first group at a predetermined temperature, to integrate anode active material layer, solid electrolyte layer and anode active material layer and make its crystallization,

The step (A) the following steps are included:

(i) positive electrode active materials or negative electrode active material are deposited in target substrate to form the first active material layer；

(ii) on first active material layer deposition solid electrolyte to form solid electrolyte layer；And

(iii) second active material layer different from first active material layer is laminated on the solid electrolyte layer, to form laminated body, the laminated body includes the combination comprising first active material layer, the solid electrolyte layer and second active material layer

47. according to the method for preparing all solid lithium secondary battery of claim 46, wherein the step (iii) further includes the following steps before the step (B): the combination that stacking at least two is prepared in the manner described above, is inserted into solid electrolyte layer therebetween to form first group.

48. according to the method for preparing all solid lithium secondary battery of claim 46, wherein depositing the active material and the solid electrolyte over the substrate by sputtering or thermal vapor deposition.

49. according to the method for preparing all solid lithium secondary battery of claim 41,

Wherein, second of phosphate cpd and the third described phosphate cpd include Li_1+xM^III _xTi^IV _2-X(PO₄)₃, wherein M^IIIIt is selected from least one of Al, Y, Ga, In and La metal ion, and 0≤x≤0.6；

The heat treatment is carried out in the atmosphere gas of the gas comprising steam and with low oxygen partial pressure；

The steam constitutes the 5-90 volume % of the atmosphere gas；And

The maximum temperature of heat treatment is 700 DEG C or higher and 1000 DEG C or lower.

50. according to the method for preparing all solid lithium secondary battery of claim 40,

Wherein the first described phosphate cpd is represented by following general formula:

LiMPO₄

Wherein M is selected from least one of Mn, Fe, Co and Ni；

The first described phosphate cpd includes Fe；

The steam constitutes the 5-90 volume % of the atmosphere gas；And

The maximum temperature of the heat treatment is 700 DEG C or higher and 1000 DEG C or lower.

51. according to the method for preparing all solid lithium secondary battery of claim 49, wherein the oxygen balance in the atmosphere gas divides PO when maintaining the heat treatment under T DEG C of constant temperature₂(atmospheric pressure) meets following formula: -0.0310T+3.5≤- log₁₀PO₂≤-0.0300T+38.1。

52. according to the method for preparing all solid lithium secondary battery of claim 50, wherein the oxygen balance in the atmosphere gas divides PO when maintaining the heat treatment under T DEG C of constant temperature₂(atmospheric pressure) meets following formula: -0.0310T+3.5≤- log₁₀PO₂≤-0.0300T+38.1。

53. according to the method for the preparation laminated body of claim 34,

LiMPO₄

Wherein M is selected from least one of Mn, Fe, Co and Ni；

The first described phosphate cpd includes Fe；

The steam constitutes the 5-90 volume % of the atmosphere gas；And

54. according to the method for the preparation laminated body of claim 53, wherein the oxygen balance in the atmosphere gas divides PO when maintaining the heat treatment under T DEG C of constant temperature₂(atmospheric pressure) meets following formula: -0.0310T+3.5≤- log₁₀PO₂≤-0.0300T+38.1。

55. according to the method for the preparation laminated body of claim 53, wherein the gas with low oxygen partial pressure includes the mixture of the gas and the gas reacted with oxygen that can discharge oxygen.

56. according to the method for preparing all solid lithium secondary battery of claim 44,

Wherein at least one of the positive electrode collector and the negative electrode collector include a kind of material selected from silver, copper and mickel,

It is lower than in anodizing-reduction equilibrium oxygen partial pres-sure atmosphere gas in partial pressure of oxygen and carries out the heat treatment；And

57. according to the method for preparing all solid lithium secondary battery of claim 56,

Wherein the atmosphere gas body includes the carbon dioxide and hydrogen no more than 3 volume %, and adjusts the partial pressure of oxygen of the atmosphere gas by changing the mixing ratio between the carbon dioxide gas and the hydrogen.

58. according to the method for preparing all solid lithium secondary battery of claim 44,

Wherein at least one of the positive electrode collector and the negative electrode collector include at least one material selected from silver, copper and mickel；

The steam constitutes the 5-90 volume % of the atmosphere gas；And

59. according to the method for preparing all solid lithium secondary battery of claim 45,

Wherein at least one of the positive electrode collector and the negative electrode collector include at least one selected from silver, copper and mickel；

The steam constitutes the 5-90 volume % of the atmosphere gas；And

60. according to all solid lithium secondary battery of claim 58, wherein the oxygen balance in the atmosphere gas divides PO when maintaining the heat treatment under T DEG C of constant temperature₂(atmospheric pressure) meets following formula: -0.0310T+3.5≤- log₁₀PO₂≤-0.0300T+38.1。

61. according to all solid lithium secondary battery of claim 59, wherein the oxygen balance in the atmosphere gas divides PO when maintaining the heat treatment under T DEG C of constant temperature₂(atmospheric pressure) meets following formula: -0.0310T+3.5≤- log₁₀PO₂≤-0.0300T+38.1。

62. according to the method for preparing all solid lithium secondary battery of claim 49, wherein the gas with low oxygen partial pressure includes the mixture of the gas and the gas reacted with oxygen that can discharge oxygen.

63. a kind of method for preparing all solid lithium secondary battery comprising following steps:

(c) positive electrode active materials green sheet is prepared using the slurry 1；

(d) solid electrolyte green sheet is prepared using the slurry 2；

(e) the second green sheet group is formed, which includes at least one combination comprising the positive electrode active materials green sheet and the solid electrolyte green sheet；And

(f) the second green sheet of Xiang Suoshu group application heat treatment, to form the laminated body of at least one entire combination comprising anode active material layer and solid electrolyte layer,

Wherein in the step (e), the solid electrolyte green sheet that the combination is prepared in the manner described above including the positive electrode active materials green sheet that at least two panels is prepared in the manner described above and at least two panels,

It is inserted into positive electrode collector between at least two panels positive electrode active materials green sheet, and is inserted into negative electrode collector between at least two panels solid electrolyte green sheet,

The positive electrode active materials include the first phosphate cpd for capableing of absorption and desorption lithium ion,

The solid electrolyte includes second of phosphate cpd with lithium-ion-conducting, and the solid electrolyte is used as negative electrode active material,

At least one of the positive electrode collector and the negative electrode collector are selected from silver, copper and mickel, and

The heat treatment is carried out in the atmosphere gas of the gas comprising steam and with low oxygen partial pressure.