JPH09283179A - Nonaqueous secondary battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a nonaqueous secondary battery having high discharge capacity, excellent charging and discharging characteristics, and high energy density. SOLUTION: In a nonaqueous secondary battery the mixture-applied portion of a negative electrode sheet is longer than a confronting positive electrode sheet in both a length direction and a width direction, and the negative electrode sheet is made by superimposing metal material mainly composed of lithium on a mixture. The weight per unit area of at least one part of the metal material superimposed on the negative electrode mixture sheet which is not opposite to the positive electrode is heavier by 10% or more and less than 400% than the weight of the metal material superimposed on the negative electrode mixture sheet which is opposite to the positive electrode.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a non-aqueous secondary battery having improved charge / discharge capacity and cycle characteristics.

[0002]

2. Description of the Related Art Lithium metal and lithium alloys are typical as negative electrode materials for non-aqueous secondary batteries. When they are used, so-called dendrites in which lithium metal grows in dendritic form during charging and discharging, Because of the cause of the internal short circuit or the high activity of the dendrite itself, there was a danger of ignition. On the other hand, fired carbonaceous materials capable of reversibly inserting and releasing lithium have come into practical use. Since this carbonaceous material has a relatively small density, it has a drawback of low capacity per volume. For this reason, although the use of a lithium foil pressed or laminated on a carbon material is described in JP-A-5-151995, it has not essentially solved the above problem.

Further, Sn, V, Si, B, Z are used as negative electrode materials.
A method using an oxide such as r or a composite oxide thereof has been proposed (JP-A-5-174818, 6-6).
0867, 6-275267, 6-325765,
6-338324, EP-615296). These oxides or composite oxide negative electrodes, by combining with a positive electrode of a transition metal compound containing certain lithium,
It is said that a non-aqueous secondary battery having a large charging capacity of 3 to 3.6 V class is provided, and dendrite is hardly generated in a practical area, and that the safety is extremely high. However, batteries using these materials have a large problem that charging / discharging cyclability is not sufficient, and particularly, charging / discharging efficiency in an initial cycle is low. That is, in the initial several cycles, a part of lithium occluded in the negative electrode during the charging process causes a plurality of irreversible side reactions, so that the lithium does not move to the positive electrode side during the discharging process, and as a result, the lithium in the positive electrode becomes ineffective. It is estimated that it was consumed and caused capacity loss. In order to compensate for these loss of capacity, it is conceivable to insert lithium corresponding to the loss into the negative electrode material in advance, but it has not yet achieved a sufficient effect.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to obtain a non-aqueous secondary battery having a high charge / discharge capacity, good charge / discharge cycle characteristics and a high energy density.

[0005]

An object of the present invention is to provide a positive electrode sheet having a layer containing a lithium-containing transition metal oxide as a main component, a layer containing a metal or metalloid oxide as a main component, and at least one water-insoluble layer. In a non-aqueous secondary battery composed of a negative electrode sheet having an auxiliary layer containing conductive particles, a non-aqueous electrolyte containing a lithium salt, and a separator, the mixture application part of the negative electrode sheet has a length direction and a width direction of the sheet. The negative electrode sheet is longer than the positive electrode sheets facing each other, and the negative electrode sheet is made by stacking a metallic material mainly containing lithium on a mixture, and the negative electrode sheet does not face at least one positive electrode. The weight per unit area of the metal material stacked on top is 10% more than the weight per unit area of the metal material stacked on the negative electrode material mixture sheet facing the positive electrode. It is accomplished by a nonaqueous secondary battery, characterized in that often above 400% or less.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below, but the present invention is not limited thereto. Positive electrode sheet having a layer mainly composed of a lithium-containing transition metal oxide, negative electrode sheet having a layer mainly composed of a metal or metalloid oxide and at least one auxiliary layer containing water-insoluble conductive particles, lithium salt In a non-aqueous secondary battery composed of a non-aqueous electrolyte and a separator containing,
The mixture application portion of the negative electrode sheet is longer than the positive electrode sheet facing each other in the length direction and the width direction of the sheet, and the negative electrode sheet is formed by stacking a metal material mainly containing lithium on the mixture. And the weight per unit area of the metal material laminated on the negative electrode mixture sheet not facing the positive electrode at least at one location is the metal material laminated on the negative electrode mixture sheet facing the positive electrode. The non-aqueous secondary battery is characterized in that the weight per unit area is 10% or more and 400% or less. Item 2. The non-aqueous secondary battery according to item 1, wherein a pattern in which a metal material containing lithium as a main component is superposed on the negative electrode sheet is at least one kind of entire surface, stripe shape, frame shape, and disk shape. A method of stacking a large amount of a metal material mainly containing lithium per unit area on a negative electrode mixture sheet facing the positive electrode on a negative electrode mixture sheet not facing the positive electrode at one location is a method of stacking the metal materials. Item 3. The non-aqueous secondary battery according to Item 1 or 2, which is a method in which the intervals between the mating pieces are made closer and / or a method in which the thickness of the metal material is increased. The thickness of the lithium-based metal material is 5 to 150.
The non-aqueous secondary battery according to any one of Items 1 to 3, wherein the non-aqueous secondary battery is μm. Item 5. The non-aqueous secondary battery according to any one of Items 1 to 4, wherein the negative electrode sheet has a coverage of a metal material mainly containing lithium of 10 to 100%. Item 6. The non-aqueous secondary battery according to any one of Items 1 to 5, wherein the negative electrode is a composite oxide containing tin.

7. The non-aqueous secondary battery according to item 6, wherein the tin-containing composite oxide is a composite oxide represented by the following general formula (1). SNM ¹ _a O _t in the general formula (1), M ¹ is Al, B, P, Si, Ge, Periodic Table 1
It represents two or more elements selected from group elements, group 2 elements, group 3 elements, and halogen elements, a represents a number of 0.2 or more and 2 or less, and t represents a number of 1 or more and 6 or less. Item 7. The non-aqueous secondary battery according to item 6, wherein the tin-containing composite oxide is a composite oxide represented by the following general formula (2). SnM ² _b O _t General formula (2) In the formula, M ² is two or more selected from Al, B, P, Ge, Group 1 element, Group 2 element, Group 3 element, and halogen element of the periodic table. , B represents a number of 0.2 or more and 2 or less, and t represents a number of 1 or more and 6 or less. Item 7. The non-aqueous secondary battery according to item 6, wherein the tin-containing composite oxide is a composite oxide represented by the following general formula (3). SnM ³ _c M ⁴ _d O _t General formula (3) In the formula, M ³ is at least 2 of Al, B, P, Si and Ge.
And M ⁴ represents at least one of Group 1 element, Group 2 element, Group 3 element and halogen element of the periodic table, and c is 0.
2 or more and 2 or less, d is 0.01 or more and 1 or less,
0.2 <c + d <2, t represents a number from 1 to 6.

Hereinafter, the configuration of the present invention will be described in detail. As a result of earnest studies on the method of preliminarily inserting lithium into the negative electrode material, the present inventors have found that at least one auxiliary layer containing water-insoluble conductive particles is provided on the layer containing at least one metal or metalloid oxide. It was found that the lithium insertion was uniform and the dendrite formation could be eliminated by installing the. Furthermore, when the cause of poor production yield of high-capacity non-aqueous secondary batteries was examined, protrusion-like irregularities on the electrode surface, scratches on the electrode surface during the process from electrode transport to battery assembly, and partial An internal short circuit occurs due to the breakage of the separator directly when the battery is wound, the slight sliding when winding the battery, or the damage to the separator due to the uneven pressure due to the unevenness caused by falling off. It was found that the contribution of It was also found that these phenomena tend to occur when a metal oxide is used for the negative electrode. In order to prevent these internal short circuits, it is effective to provide layers for protecting the electrode surface, and the installation of these layers improves the production yield and makes lithium insertion uniform. I also understood that.

In addition, by stacking a metal material mainly containing lithium on the negative electrode sheet, particularly by increasing the amount of lithium in the portion not facing the positive electrode relative to the portion facing the positive electrode, the positive electrode sheet The potential is flattened,
We have found that the cycle characteristics are mainly improved. It is preferable to use lithium metal as the metal containing lithium as a main component, but a metal having a purity of 90% by weight or more is preferable, and a metal having a purity of 98% by weight or more is particularly preferable. The lithium superposition pattern on the negative electrode sheet is selected from the whole surface, stripes, frame shape, circular shape, or a combination thereof. A particularly preferred pattern is stripes. The term "overlapping" as used herein means that a metal foil mainly containing lithium is pressure-bonded onto a sheet having a negative electrode mixture and an auxiliary layer. In either case, the amount of lithium inserted can be arbitrarily controlled by the amount of lithium to be superposed. The preliminary insertion amount of lithium is preferably 0.5 to 4.0 equivalents, more preferably 1 to 3.5 equivalents, and particularly preferably 1.2 to the negative electrode material.
It is 3.2 equivalents. When more than 3.2 equivalents of lithium is preliminarily inserted in the negative electrode material, the deterioration of the cycle property is extremely unfavorable. It is possible that local overcharge of the negative electrode active material may cause deterioration of cycleability, but it is not clear exactly.

It is preferable that a metal foil having a constant thickness is laminated on the entire surface of the negative electrode sheet in the overlapping pattern. However, since lithium preliminarily inserted in the negative electrode material gradually diffuses in the negative electrode material by aging, it is not the entire surface of the sheet. Partial overlapping of stripes, frames, or discs may also be used. In these partial overlaps, uniform pre-insertion of lithium can be achieved by controlling the size of the metal foil. It is preferable that the stripes be overlapped with the negative electrode sheet in the vertical direction or the horizontal direction in terms of manufacturing suitability. The overlapping interval is preferably constant, but may not be constant. It is also possible to use a grid pattern in which the vertical direction and the horizontal direction are combined, which is particularly preferable for uniform preliminary lithium insertion. The size of the stripe is arbitrarily selected according to the size of the negative electrode sheet, but the width of the stripe is preferably from half the length of one surface of the negative electrode sheet to 0.5 mm. More preferably, the half length of one side of the load sheet is up to 1 mm, and particularly preferably the half length of one side of the negative electrode sheet is up to 1.5 mm. 0.
If the stripe width is smaller than 5 mm, it is difficult to cut or handle the metal foil, which is not preferable. The stripe width here means the length direction of the electrode sheet. Further, it is particularly preferable that the stripe length is the same as the electrode width. When the stripes are overlapped with each other, the patterns on the front and back of the sheet may be the same or different, but the method of sticking the back surface to the part of the surface where the metal foil is not stuck is preferable.

It is preferable that the negative electrode sheet is designed so that both the length and width of the portion coated with the mixture are wider than the portion coated with the mixture on the positive electrode sheet. That is, in the wound state of the negative electrode sheet and the positive electrode sheet that face each other with the separator interposed therebetween, the negative electrode mixture portion has a portion that does not face the positive electrode. The length of the non-opposing portion is preferably 0.1 to 10 mm, particularly preferably 0.5 to 5 mm in the width direction of the sheet. Further, the lengthwise direction of the sheet is preferably 0.1 to 50 mm, particularly preferably 0.5 to 30 mm.
At this time, as an average value, the amount of lithium superposed on the negative electrode mixture is more superposed per unit area of the sheet on a portion which does not face than on the negative electrode mixture which faces the positive electrode. In particular, the effect is great when a large number of sheets are superposed on non-opposing portions in the length direction of the sheet. The amount of overlapping on the non-facing portion is preferably 110 to 500% as an average value with respect to the amount of overlapping on the facing portion, and 120 to 40%.
0% is more preferable, and 130 to 250% is particularly preferable. As a method of superposing more lithium per unit area on the non-opposing portion, a method of superposing lithium thicker on the non-opposing portion of the negative electrode mixture is preferable. In the case of stacking lithium in a stripe shape, a frame shape, or a disk shape, a method of stacking lithium in a non-opposing portion with a close interval is also preferable. Further, it is possible to combine any of stripe-shaped, frame-shaped, and disk-shaped patterns so that more lithium is superposed on the non-opposing portion. The coverage of the metal foil superposed on the negative electrode sheet is preferably 10 to 100%, more preferably 15 to 100%, and 20 to 100%.
Is particularly preferred. If it is 10% or less, the preliminary insertion of lithium may be nonuniform, which is not preferable. Further, from the viewpoint of uniformity, the thickness of the metal foil mainly containing lithium is 5
The thickness is preferably ˜150 μm, more preferably 5 to 100 μm. Particularly preferably, it is 10 to 75 μm.

In this method, the side reaction lithium is supplied not from the positive electrode active material but from stacked lithium into the negative electrode material. It is preferable that the handling atmosphere for cutting and pasting the metal foil mainly containing lithium is dry air or argon gas atmosphere having a dew point of -30 ° C or lower and -80 ° C or higher. -4 for dry air
0 ° C or lower and -80 ° C or higher are more preferable. Carbon dioxide may be used together during handling. Particularly, in the case of an argon gas atmosphere, it is preferable to use a carbon dioxide gas in combination.

For preliminarily inserting lithium into the negative electrode material, a metal foil mainly containing lithium and a metal sheet having an opening such as an expanded metal or metal particles having a particle size of 100 μm or less are superposed on the negative electrode sheet. A method of assembling a non-aqueous secondary battery together with a separator and a positive electrode sheet after compression processing using a calendar press machine as required, and injecting an electrolytic solution and aging for a certain period of time can be used. Further, butyl lithium can be used to insert lithium into the negative electrode material. The battery of the present invention may be charged immediately after assembly, but it is preferable that the battery is aged before charging so that lithium is more uniformly diffused in the negative electrode material. Aging is 0 to 80 ° C for 1 hour to 6
0 day is preferable, but 5 hours to 30 days at 30 to 60 ° C., 3
Most preferably, the temperature is 0 to 60 ° C. for 10 hours to 25 days. In addition, it is preferable that the battery voltage is set to 1.0 to 3.5 V by charging before or during aging for uniform insertion of lithium.

Next, the auxiliary layer and the protective layer provided on the electrode surface will be described. Providing a layer different from the active material on the electrode surface, for example, a protective layer, has been studied in the past, and when a lithium metal or alloy is used as the negative electrode, a protective layer made of carbon containing a carbon material or metal powder is used. Provision of layers is disclosed in JP-A-4-229562 and US Pat. No. 5,387,4.
79 and JP-A-3-297072.
However, the purpose of these patents is to protect the active part of the lithium metal surface and prevent the decomposition of the electrolytic solution due to contact with the electrolytic solution and the formation of a passive film due to decomposition products, etc. The structure and the object of the present invention are different from those of the metal oxide negative electrode. Further, JP-A-61-263069 describes that a transition metal oxide is used as a negative electrode material and the surface thereof is coated with an ion conductive solid electrolyte. In Examples, a solid electrolyte is formed on a layer of the transition metal oxide. It is described that the film is provided by sputtering. The purpose of this patent is to prevent the dendritic deposition of lithium and to prevent the decomposition of the electrolytic solution, like the above-mentioned patent, which is different from the present invention. Further, an ion-conductive solid electrolyte has solubility in water and hygroscopicity, which is not preferable.

Further, Japanese Patent Laid-Open No. 61-7577 describes a protective layer made of a substance having both electron conductivity and ionic conductivity on the surface of the positive electrode, and as a substance having electron-ion mixed conductivity. Oxides of tungsten, molybdenum and vanadium are described as being preferred. However, these oxides are compounds capable of inserting and extracting lithium, and are not preferred in the present invention.

In the present invention, the auxiliary layer provided on the negative electrode sheet is composed of at least one layer and may be composed of a plurality of layers of the same kind or different kinds. These auxiliary layers are
It is composed of water-insoluble conductive particles and a binder. As the binder, a binder used when forming an electrode mixture described later can be used. The ratio of the conductive particles contained in the auxiliary layer is preferably 2.5% by weight or more and 96% by weight or less, and 5
The content is more preferably not less than 95% by weight and more preferably not less than 10% and not more than 93% by weight. Examples of the water-insoluble conductive particles of the present invention include metal particles, metal oxides, metal fibers, carbon fibers, and carbon particles such as carbon black and graphite. The solubility in water is 100 PPM or less, preferably insoluble. Among these water-insoluble conductive particles, those having low reactivity with an alkali metal, particularly lithium, are preferable, and metal powder and carbon particles are more preferable. The electric resistivity at 20 ° C. of the elements constituting the particles is preferably 5 × 10 ⁹ Ω · m or less.

As the metal powder, a metal having low reactivity with lithium, that is, a metal which is unlikely to form a lithium alloy is preferable, and specifically, copper, nickel, iron, chromium, molybdenum, titanium, tungsten, and tantalum are preferable. The shape of these metal powders may be any of a needle shape, a column shape, a plate shape, and a lump shape, and the maximum diameter is preferably 0.02 μm or more and 20 μm or less, more preferably 0.1 μm or more and 10 μm or less. It is preferable that the surface of these metal powders is not excessively oxidized. When the surfaces are oxidized, it is preferable to perform heat treatment in a reducing atmosphere.

As the carbon particles, there can be used known carbon materials which are conventionally used as a conductive material when the electrode active material is not conductive. Examples of these materials include carbon black such as thermal black, furnace black, channel black and lamp black, natural graphite such as scaly graphite, scaly graphite and earth graphite, artificial graphite, carbon fiber and the like. In order to mix and disperse these carbon particles with a binder, it is preferable to use carbon black and graphite in combination. As carbon black, acetylene black and Ketjen black are preferable. The carbon particles are preferably 0.01 μm or more and 20 μm or less, more preferably 0.02 μm or more and 10 μm or less.

For the purpose of improving the strength of the coating film, particles having substantially no conductivity may be mixed in the auxiliary layer. Fine particles of Teflon, SiC,
Examples include aluminum nitride, alumina, zirconia, magnesia, mullite, forsterite, and steatite. These particles contain 0.0% of the conductive particles.
It is preferable to use at least 1 and at most 10 times.

When the negative electrode is formed by coating the mixture on both sides of the current collector, these auxiliary layers may be formed on both sides, or may be formed on only one side. You may.
The coating method of the auxiliary layer is such that a material that is capable of reversibly occluding and releasing lithium is coated on the current collector with a mixture mainly composed of a metal or a semi-metal oxide, and then the auxiliary layers are sequentially formed. A sequential method of coating may be used, or a simultaneous coating method of simultaneously coating the mixture layer and the auxiliary layer may be used.

Next, the protective layer provided on the positive electrode sheet will be described. The protective layer is composed of at least one layer and may be composed of a plurality of layers of the same kind or different kinds. These protective layers may have substantially no electron conductivity, that is, may be insulating layers, or may be conductive layers like the negative electrode sheet. Further, a form in which an insulating layer and a conductive layer are stacked may be employed. The thickness of the protective layer is preferably 1 μm or more and 40 μm or less, more preferably 2 μm or more and 30 μm or less. Further, it is desirable that the protective layer containing these particles does not melt at 300 ° C. or lower and does not form a new film. When the protective layer is composed of water-insoluble conductive particles and a binder, the conductive particles used for the auxiliary layer of the negative electrode sheet can be used. The type and size of the conductive particles preferably used are the same as those of the negative electrode sheet.

When the protective layers are insulating, these layers preferably contain organic or inorganic particles. These particles are preferably 0.1 μm or more and 20 μm or less,
More preferably, it is not less than μm and not more than 15 μm. The preferred organic particles are a crosslinked latex or a powdery fluororesin, and those which do not decompose or form a film at 300 ° C. or lower are preferred. More preferred is a fine powder of Teflon. Examples of the inorganic particles include carbides, silicides, nitrides, sulfides, and oxides of metals and nonmetallic elements. Among carbides, silicides and nitrides, SiC,
Aluminum nitride (AlN), BN, and BP are preferable because they have high insulating properties and are chemically stable, and in particular, BeO, Be, and B
SiC using N as a sintering aid is particularly preferred.

Among chalcogenides, oxides are preferred.
In addition, an oxide that is difficult to oxidize or reduce is preferable. this
As the oxide,_TwoO_Three, As_FourO₆, B_TwoO_Three, B
aO, BeO, CaO, Li_TwoO, K_TwoO, Na_TwoO, I
n_TwoO_Three, MgO, Sb_TwoO_Five, SiO_Two, SrO, ZrO
_FourIs raised. Among these, Al_TwoO_Three, BaO, B
eO, CaO, K_TwoO, Na_TwoO, MgO, SiO_Two, S
rO, ZrO_FourIs particularly preferred. These oxides are
It may be alone or may be a complex oxide. Complex oxide
Preferred compounds include mullite (3Al _TwoO_Three
・ 2SiO_Two), Steatite (MgO / SiO)_Two),
Forsterite (2MgO ・ SiO_Two), Cordera
Ito (2MgO.2Al_TwoO_Three・ 5SiO_Two) Etc.
You can These insulating inorganic compound particles are
Depending on the conditions such as control of growth conditions and grinding, 0.1 μm or more,
20 μm or less, particularly preferably 0.2 μm or more, 15 μm
Used as particles having a size of m or less.

The protective layer is made of these conductive particles and / or
Alternatively, it is formed using particles having substantially no conductivity and a binder. As the binder, a binder used when forming an electrode mixture described later can be used. The ratio of the particles and the binder is 40% by weight or more based on the total weight of both,
It is preferably 96% by weight or less, more preferably 50% by weight or more and 94% by weight or less.

Hereinafter, other materials for manufacturing the non-aqueous secondary battery of the present invention and a manufacturing method will be described in detail. The positive and negative electrodes used in the non-aqueous secondary battery of the present invention can be made by coating a positive electrode mixture or a negative electrode mixture on a current collector. The positive electrode or negative electrode mixture can contain a conductive agent, a binder, a dispersant, a filler, an ionic conductive agent, a pressure enhancer, and various additives, respectively, in addition to the positive electrode active material or the negative electrode material.

The negative electrode material of the present invention is preferably composed mainly of a transition metal, a metal of Group 13 to 15 of the periodic table, or an oxide of a metalloid element. As the negative electrode material of the present invention, a light metal, a light metal alloy, or a carbonaceous compound may be used in combination with a transition metal, a metal of Group 13 to 15 of the periodic table, or an oxide of a metalloid element. Examples of light metals and light metal alloys include lithium and lithium alloys. The carbonaceous compound is selected from natural graphite, artificial graphite, vapor grown carbon, calcined organic material, and the like, and preferably contains a graphite structure. In addition to carbon, carbonaceous compounds include other compounds such as B, P, N, S, SiC and B ₄
0 to 10% by weight of C may be contained.

As the transition metal compound, V, Ti,
A single or complex oxide of Fe, Mn, Co, Ni, Zn, W and Mo is preferable. As a more preferable compound,
Of JP-A-6-44972 Patent according _{Li p Co q V 1-q} O z ( where p = 0.1~2.5, q = 0~1, z = 1.3~
4.5) can be mentioned. The compound of a metal other than a transition metal or a metalloid is composed of an element of Group 13 to Group 15 of the periodic table, Ga, Si, Sn, Ge, Pb, Sb, Bi, or a combination of two or more thereof. An oxide is chosen. For example, Ga ₂ O ₃ , SiO, GeO, Ge
O ₂ , SnO, SnO ₂ , SnSiO ₃ , PbO, Pb
_{O 2, Pb 2 O 3,} Pb 2 O 4, Pb 3 O 4, Sb 2 O 3, Sb 2
O ₄ , Sb ₂ O ₅ , Bi ₂ O ₃ , Bi ₂ O ₄ , Bi ₂ O ₅ , Sn
SiO _{3 and the} like are preferable. Further, these may be composite oxides with lithium oxide, such as Li ₂ GeO ₃ and Li ₂ SnO ₂ .

The above complex oxide is preferably mainly amorphous when incorporated in a battery. The term “mainly amorphous” used herein means an X-ray diffraction method using CuKα rays and a 2θ value of 2
It is a product having a broad scattering band having an apex at 0 ° to 40 ° and may have a crystalline diffraction line. Preferably, the strongest intensity of the crystalline diffraction lines observed in the 2θ value of 40 ° or more and 70 ° or less is 5 of the diffraction line intensity of the apex of the broad scattering band observed in the 2θ value of 20 ° or more and 40 ° or less.
It is preferably 00 times or less, more preferably 1
It is 00 times or less, particularly preferably 5 times or less, and most preferably it has no crystalline diffraction line.

The above composite oxides are B, Al, Ga, I.
n, Tl, Si, Ge, Sn, Pb, P, As, Sb,
It is a complex oxide of three or more elements in Bi. Particularly preferred is a composite oxide composed of three or more elements selected from B, Al, Si, Ge, Sn, and P. These complex oxides may contain an element of Group 1 to 3 or a halogen element of the periodic table mainly for modifying the amorphous structure. Among the above-mentioned negative electrode materials, an amorphous complex oxide containing tin as a main component is particularly preferable and is represented by the following general formula (1). SNM ¹ _a O _t in the general formula (1), M ¹ is Al, B, P, Si, Ge, Periodic Table 1
A represents a number of 0.2 or more and 2 or less, and t represents a number of 1 or more and 6 or less. .

Of the general formula (1), the compound of the following general formula (2) is more preferable. SnM ² _b O _t General formula (2) In the formula, M ² is two or more selected from Al, B, P, Ge, Group 1 element, Group 2 element, Group 3 element, and halogen element of the periodic table. B is a number of 0.2 or more and 2 or less, and t is a number of 1 or more and 6 or less.

Of the general formula (1), the compound of the following general formula (3) is more preferable. SnM ³ _c M ⁴ _d O _t General formula (3) In the formula, M ³ is at least 2 of Al, B, P, Si and Ge.
And M ⁴ represents at least one of Group 1 element, Group 2 element, Group 3 element and halogen element of the periodic table, and c is 0.
A number of 2 or more and 2 or less, d is a number of 0.01 or more and 1 or less, 0.2 <c + d <2, and t represents a number of 1 or more and 6 or less. M ³ and M ⁴ are elements for amorphizing the compound of the general formula (3) as a whole, M ³ is an element that can be made amorphous, and 2 of Al, B, P, Si and Ge are used. It is preferable to use a combination of two or more species. M ⁴ is an element that can be modified to be amorphous, and is a group 1 element, a group 2 element of the periodic table,
Group 3 element, halogen element, K, Na, Cs, M
g, Ca, Ba, Y and F are preferred. b is 0.2 or more,
2 or less, c is 0.01 or more and 1 or less, 0.2
<B + c <2, t represents a number of 1 or more and 6 or less.

The amorphous composite oxide of the present invention may employ either a calcination method or a solution method, but the calcination method is more preferable. In the baking method, it is preferable to mix well the oxides or compounds of the elements described in the general formula (1) and then bake to obtain an amorphous composite oxide.

The firing conditions are preferably a heating rate of 5 ° C. or more and 200 ° C. or less per minute, a firing temperature of 500 ° C. or more and 1500 ° C. or less, and a firing time. Is more than 1 hour 10
It is preferably 0 hours or less. And, it is preferable as the descending rate of temperature or less per minute 2 ℃ least 10 ⁷ ° C..

The rate of temperature rise in the present invention means "50% of the firing temperature (indicated in ° C)" to 80 of the "firing temperature (indicated in ° C)"
% ", Which is the average rate of temperature increase until the temperature reaches"% ", and the term" cooling rate "in the present invention refers to" 80% of the firing temperature (° C) ".
This is the average rate of temperature decrease from the point when the temperature reaches “50% of the firing temperature (expressed in ° C.)”. The temperature may be cooled in a firing furnace, or may be taken out of the firing furnace and put into, for example, water for cooling. Also, ceramic processing (Gihodo Publishing 1987), page 217, gun method, Hammer-Anvi
It is also possible to use ultra-quenching methods such as the l method, slap method, gas atomizing method, plasma spray method, centrifugal quenching method, melt drag method and the like. See also New Glass Handbook (Maruzen 19
91) It may be cooled by using the single roller method or the twin roller method described on page 172. For materials that melt during firing,
The fired product may be continuously taken out while supplying the raw material during firing. In the case of a material that melts during firing, it is preferable to stir the melt.

The firing gas atmosphere is preferably an atmosphere having an oxygen content of 5% by volume or less, and more preferably an inert gas atmosphere. Examples of the inert gas include nitrogen, argon, helium, krypton, xenon, and the like. The most preferred inert gas is pure argon. The average particle size of the compound of the present invention is 0.1 to 60 μm.
m is preferred. In order to obtain a predetermined particle size, a well-known pulverizer or classifier is used. For example, a mortar, a ball mill, a sand mill, a vibrating ball mill, a satellite ball mill, a planetary ball mill, a swirling airflow type jet mill, a sieve and the like are used. At the time of pulverization, wet pulverization in the presence of water or an organic solvent such as methanol can also be performed as necessary. Classification is preferably performed to obtain a desired particle size. The classification method is not particularly limited, and a sieve, an air classifier, or the like can be used as necessary. Classification can be performed both in a dry type and a wet type.

Examples of the negative electrode material of the present invention are shown below, but the present invention is not limited thereto. SnAl _0.1
B _0.3 P _0.4 K _0.2 O _2.7 , SnAl _0.1 B _0.3 P _0.4 Na _{0.2
O 2.7, SnAl 0.1 B 0.3 P} 0.4 Rb 0.2 O 2. 7, SnAl
_{0.1 B 0.3 P 0.4 Cs 0.2 O} 2.7, SnAl 0.1 B 0 .5 P 0.5 M
g _0.1 F _0.2 O _3.15 , SnAl _0.1 B _0.5 P _0.5 Ba _0.08 F
_0.08 O _3.19 , SnAl _0.2 B _0.4 P _0.4 O _2.9 , SnAl
_0.3 B _0.5 P _0.2 O _2.7 , SnAl _0.3 B _0.7 O _2.5 , SnB
_0.2 P _0.6 Ba _0.08 F _0.08 O _2.84 , SnB _0.4 P _0.4 Ba
_0.1 F _0.1 O _2.65 , SnB _0.5 P _0.5 O ₃ , SnB _0.5 P _0.5
Mg _{0. 1} O _3.1,

SnB _0.5 P _0.5 Mg _0.1 F _0.2 O ₃ , SnB
_{0.5 P 0.5 Li 0. 1 Mg 0.1} F 0.2 O 3.05, SnB 0.5 P 0.5
_{K 0.1 Mg 0.1 F 0 .2 O} 3.05, SnB 0.5 P 0.5 K 0.05 Mg
_0.05 F _0.1 O _3.03 , SnB _0.5 P _0.5 K _0.05 Mg _0.1 F _{0.2
O 3.03, SnB 0.5 P 0. 5} Cs 0.1 M g 0.1 F 0.2 O 3.05,
SnB _0.5 P _0.5 Cs _0.05 Mg _0.05 F _0.1 O _3.03 , SnB
_{0.5 P 0.5 Mg 0.1 F 0.1 O} 3. 05, SnB 0.5 P 0.5 Mg 0.1
F _0.2 O ₃ , SnB _0.5 P _0.5 Mg _0.1 F _0.06 O _3.07 , Sn
B _0.5 P _0.5 Mg _0.1 F _0.14 O _3.03 , SnPBa _0.08 O
_3.58 , SnPK _0.1 O _3.55 , SnPK _0.05 Mg _0.05 O
_{3.58, SnPCs 0 .1 O 3.55,} SnPBa 0.08 F 0.08 O
_3.54 , SnPK _0.1 Mg _0.1 F _0.2 O _3.55 , SnPK _0.05
Mg _0.05 F _0.1 O _3.53 , SnPCs _0.1 Mg _0.1 F _0.2 O
_{3.55, SnPCs 0.05 Mg 0.05 F 0.1} O 3. 53,

Sn _1.1 B _0.2 P _0.6 Ba _0.08 F
_0.08 O _2.94 , Sn _1.1 B _0.2 P _0.6 Li _0.1 K _0.1 Ba _0.1 F
_0.1 O _3.05 , Sn _1.1 B _0.4 P _0.4 Ba _0.08 O _2.74 , Sn
_1.1 PCs _0.05 O _3.63 , Sn _1.1 PK _0.05 O _3.63 , Sn
_1.2 Al _0.1 B _0.3 P _0.4 Cs _0.2 O _2.9 , Sn _1.2 B _0.2 P
_0.6 Ba _0.08 O _3.08 , Sn _1.2 B _0.2 P _0.6 Ba _0.08 F _0.08
O _3.04 , Sn _1.2 B _0.2 P _0.6 Mg _0.04 Ba _0.04 O _3.08 ,
Sn _1.2 B _0.3 P _0.5 Ba _0.08 O _2.98 , Sn _1.3 Al _0.1 B
_0.3 P _0.4 Na _0.2 O ₃ , Sn _1.3 B _0.4 P _0.4 Ca
_{0.2 O 3.1, Sn 1.3 B 0.4} P 0. 4 Ba 0.2 O 3.1, Sn 1.4 P
K _0.2 O ₄ , Sn _1.4 Ba _0.1 PK _0.2 O _4.15 , Sn _1.4 Ba
_{0.2 PK 0.2 O 4.3, Sn 1.4} Ba 0 .2 PK 0.2 Ba 0.1 F 0.2
O _4.3 , Sn _1.4 PK _0.3 O _4.05 , Sn _1.5 PK
_0.2 O _4.1 , Sn _1.5 PK _0.1 O _4.05 , Sn _1.5 PCs _0.05
O _4.03 , Sn _1.5 PCs _0.05 Mg _0.1 F _0.2 O _4.03 , Sn ₂
P ₂ O ₇ ,

SnSi _0.5 Al _0.1 B _0.2 P _0.1 Ca _0.4 O
_{3.1, SnSi 0. 4 Al 0.2 B} 0.4 O 2.7, SnSi 0.5 Al
_0.2 B _0.1 P _0.1 Mg _0.1 O _2.8 , SnSi _0.6 Al _0.2 B _{0.2
O 2.8, SnSi 0. 5 Al 0.3} B 0.4 P 0.2 O 3.55, SnS
i _0.5 Al _0.3 B _0.4 P _0.5 O _4.30 , SnSi _0.6 Al _0.1 B
_0.1 P _0.3 O _3.25 , SnSi _0.6 Al _0.1 B _0.1 P _0.1 Ba
_0.2 O _2.95 , SnSi _0.6 Al _0.1 B _0.1 P _0.1 Ca _0.2 O
_{2.95, SnSi 0.6 Al 0.1 B 0.} 2 Mg 0.2 O 2.85, SnS
i _0.6 Al _0.1 B _0.3 P _0.1 O _3.05 , SnSi _0.6 Al _0.2
Mg _0.2 O _2.7 , SnSi _0.6 Al _0.2 Ca _0.2 O _2.7 , Sn
Si _0.6 Al _0.2 P _0.2 O ₃ , SnSi _0.6 B _0.2 P _0.2 O ₃ ,
SnSi _0.8 Al _0.2 O _2.9 , SnSi _0.8 Al _0.3 B _0.2
P _0.2 O _3.85 , SnSi _0.8 B _0.2 O _2.9 , SnSi _0.8 B
_{a 0.2 O 2.8, SnSi 0.8 Mg} 0.2 O 2 .8, SnSi 0.8 C
a _0.2 O _2.8 , SnSi _0.8 P _0.2 O _3.1 ,

Sn _0.9 Mn _0.3 B _0.4 P _0.4 Ca _0.1 Rb _{0.1
O 2.95, Sn 0 .9 Fe 0.3} B 0.4 P 0.4 Ca 0.1 Rb 0.1 O
_2.95 , Sn _0.8 Pb _0.2 Ca _0.1 P _0.9 O _3.35 , Sn _0.3 G
_{e 0.7 Ba 0.1 P 0. 9 O} 3.35, Sn 0.9 Mn 0.1 Mg 0.1 P
_0.9 O _3.35 , Sn _0.2 Mn _0.8 Mg _0.1 P _0.9 O _3.35 , Sn
_{0.7 Pb 0.3 Ca 0.1 P 0. 9} O 3.35, Sn 0.2 Ge 0.8 Ba
_0.1 P _0.9 O _3.35 .

The chemical formula of the compound obtained by firing can be calculated from an inductively coupled plasma (ICP) emission spectral analysis method as a measuring method, and as a simple method from a weight difference between powders before and after firing.

Various elements can be contained in the negative electrode material of the present invention. For example, lanthanoid metals (Hf, T
a, W, Re, Os, Ir, Pt, Au, Hg), and various compounds that increase electron conductivity (for example, Sn, In, N).
b) may be included. The amount of the compound to be added is preferably 0 to 5 mol%.

The surface of the oxide positive electrode active material or negative electrode material used in the present invention can be coated with an oxide having a chemical formula different from those of the positive electrode active material or negative electrode material used. The surface oxide is preferably an oxide containing a compound that dissolves in both acidity and alkalinity. Further, a metal oxide having high electron conductivity is preferable. For example, PbO ₂ , Fe ₂ O
₃ , SnO ₂ , In ₂ O ₂ , ZnO and the like or oxides thereof preferably contain a dopant (for example, a metal having a different valence in the oxide, a halogen element, etc.).
Particularly preferably, SiO ₂ , SnO ₂ , Fe ₂ O ₃ , Zn
O and PbO ₂ . The amount of metal oxide used for these surface treatments is 0.
1 to 10% by weight is preferable, 0.2 to 5% by weight is particularly preferable, and 0.3 to 3% by weight is most preferable. In addition to this, the surfaces of the positive electrode active material and the negative electrode material can be modified. For example, the surface of the metal oxide may be treated with an esterifying agent, treated with a chelating agent, or treated with a conductive polymer, polyethylene oxide, or the like.

The positive electrode active material used in the present invention may be a transition metal oxide capable of reversibly inserting and releasing lithium ions, but a lithium-containing transition metal oxide is particularly preferable.
Preferred lithium-containing transition metal oxide positive electrode active materials used in the present invention include lithium-containing Ti, V, Cr,
Examples thereof include oxides containing Mn, Fe, Co, Ni, Cu, Mo and W. Alkali metals other than lithium (elements IA and IIA of the periodic table) and / or Al, G
a, In, Ge, Sn, Pb, Sb, Bi, Si, P,
B or the like may be mixed. The mixing amount is 0 with respect to the transition metal.
~ 30 mol% is preferred. More preferred lithium-containing transition metal oxide positive electrode active material used in the present invention,
Lithium compound / transition metal compound (here, transition metal is Ti, V, Cr, Mn, Fe, Co, Ni, Mo,
W) is a total molar ratio of 0.1.
It is preferable to mix and synthesize so that it becomes 3-2.2.

Particularly preferable lithium-containing transition metal oxide positive electrode active material used in the present invention is a lithium compound / transition metal compound (wherein the transition metal is V or C).
At least 1 selected from r, Mn, Fe, Co, and Ni
It is preferable to mix and synthesize so that the total molar ratio of the (species) is 0.3 to 2.2. A particularly preferable lithium-containing transition metal oxide positive electrode active material used in the present invention is Li _x QO _y (wherein Q is a transition metal containing at least one of Co, Mn, Ni, V, and Fe).
It is preferable that x = 0.02 to 1.2 and y = 1.4 to 3). As Q, in addition to transition metals, Al, Ga, I
You may mix n, Ge, Sn, Pb, Sb, Bi, Si, P, B etc. The mixing amount is 0 to 30 with respect to the transition metal
Molar% is preferred.

More preferred lithium-containing metal oxide positive electrode active materials used in the present invention are Li _x CoO ₂ ,
Li _x NiO ₂ , Li _x MnO ₂ , Li _x Co _a Ni _1-a O ₂ ,
Li _z Co _b V _1-b O _z , Li _x Co _b Fe _1-b O ₂ , Li _x M
_{n 2 O 4, Li x Mn} c Co 2-c O 4, Li x Mn c Ni
_{2-c O 4, Li x} Mn c V 2-c O z, Li x Mn c Fe 2-c O 4,
Li _x Co _b B _1-b O ₂ , Li _x Co _b Si _1-b O ₂ , Li _x M
A mixture of n ₂ O ₄ and MnO _2, a mixture of Li _2x MnO ₃ and MnO _2, a mixture of Li _x MnO ₄ , and a mixture of Li _2x MnO ₃ and MnO ₂ (where x = 0.02 to 1.2, a = 0. 1 to 0.
9, b = 0.8 to 0.98, c = 1.6 to 1.96, z
= 2.01 to 5).

More preferable lithium-containing metal oxide positive electrode active material used in the present invention is Li _x CoO ₂ ,
Li _x NiO ₂ , Li _x MnO ₂ , Li _x Co _a Ni _1-a O ₂ ,
Li _x Co _b V _1-b O _z , Li _x Co _b Fe _1-b O ₂ , Li _x M
_{n 2 O 4, Li x Mn} c Co 2-c O 4, Li x Mn c Ni
_{2-c O 4, Li x} Mn c V 2-c O 4, Li x Mn c Fe 2-c O
₄ (where x = 0.02 to 1.2, a = 0.10 to 0.
9, b = 0.8 to 0.98, c = 1.6 to 1.96, z
= 2.01 to 2.3). The most preferable lithium-containing transition metal oxide positive electrode active material used in the present invention is Li _x CoO ₂ , Li _x NiO ₂ , Li _x Mn.
O ₂ , Li _x Co _a Ni _{1 -a} O ₂ , Li _x Mn ₂ O ₄ , Li _x C
_{o b V 1-b O z} ( wherein x = 0.02~1.2, a = 0.
1 to 0.9, b = 0.9 to 0.98, z = 2.02
2.3). Here, the above-mentioned x value is a value before the start of charge / discharge, and increases / decreases due to charge / discharge.

The positive electrode active material can be synthesized by a method of mixing and firing a lithium compound and a transition metal compound or by a solution reaction, but a firing method is particularly preferable. The firing temperature used in the present invention may be a temperature at which a part of the mixed compound used in the present invention decomposes and melts.
50-2000 ° C is preferred, and especially 350-1500 ° C
Is preferred. In firing, it is preferable to calcine at 250 to 900 ° C. The firing time is preferably from 1 to 72 hours, more preferably from 2 to 20 hours. The mixing method of the raw materials may be dry or wet. After firing, 20
Annealing may be performed at 0 ° C. to 900 ° C. The firing gas atmosphere is not particularly limited, and may be an oxidizing atmosphere or a reducing atmosphere. For example, in air, or a gas whose oxygen concentration is adjusted to an arbitrary ratio, or hydrogen, carbon monoxide,
Examples include nitrogen, argon, helium, krypton, xenon, and carbon dioxide.

In synthesizing the positive electrode active material of the present invention, as a method of chemically inserting lithium ions into a transition metal oxide, it is synthesized by reacting lithium metal, lithium alloy or butyl lithium with the transition metal oxide. The method is preferred. The average particle size of the positive electrode active material used in the present invention is not particularly limited, but is preferably 0.1 to 50 μm.
The specific surface area is not particularly limited.
01 to 50 m ² / g is preferable. The pH of the supernatant when 5 g of the positive electrode active material is dissolved in 100 ml of distilled water is preferably 7 or more and 12 or less. In order to obtain a predetermined particle size, a well-known pulverizer or classifier is used. For example, a mortar, a ball mill, a vibrating ball mill, a vibrating mill, a satellite ball mill, a planetary ball mill, a swirling air jet mill, a sieve, and the like are used. The positive electrode active material obtained by firing may be used after being washed with water, an acidic aqueous solution, an alkaline aqueous solution, or an organic solvent.

The combination of the negative electrode material and the positive electrode active material used in the present invention is preferably the compound represented by the general formula (1) and Li _x CoO ₂ , Li _x NiO ₂ , and Li _x Co _a Ni.
_1-a O ₂ , Li _x MnO ₂ , Li _x Mn ₂ O ₄ , or Li _x
Co _b V _1-b O ₂ (where x = 0.02 to 1.2, a =
0.1-0.9, b = 0.9-0.98, z = 2.02
To 2.3), it is possible to obtain a non-aqueous secondary battery having a high discharge voltage, a high capacity, and excellent charge / discharge cycle characteristics.

The equivalent amount of lithium inserted into the negative electrode material of the present invention is 3 to 10 equivalents, and the amount ratio with the positive electrode active material is determined according to this equivalent amount. It is preferable to use a ratio of 0.5 to 2 times the used amount ratio based on this equivalent. When the lithium supply source is other than the positive electrode active material (for example, lithium metal, alloy, butyl lithium, etc.), the amount of the positive electrode active material used is determined according to the lithium release equivalent of the negative electrode material. Also in this case, it is preferable to multiply the used amount ratio based on this equivalent by a factor of 0.5 to 2 times.

A conductive agent, a binder, a filler or the like can be added to the electrode mixture. The conductive agent may be any electronic conductive material that does not cause a chemical change in the configured battery. Usually, natural graphite (flaky graphite, flaky graphite, earthy graphite, etc.), artificial graphite, carbon black, acetylene black, Ketjen black, carbon fiber or metal (copper, nickel, aluminum, silver, etc.) powder, metal fiber or Conductive materials such as polyphenylene derivatives
It can be included as a seed or a mixture thereof.
A combination of graphite and acetylene black is particularly preferred. The addition amount is preferably 1 to 50% by weight, particularly 2 to 30% by weight.
% By weight is preferred. For carbon and graphite, 2 to 15% by weight is preferable.

The binder is usually starch, polyvinyl alcohol, carboxymethyl cellulose, hydroxypropyl cellulose, regenerated cellulose, diacetyl cellulose, polyvinyl chloride, polyvinyl pyrrolidone,
Tetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, ethylene-propylene-diene terpolymer (EPDM), sulfonated EPDM, styrene butadiene rubber, polybutadiene, fluoro rubber,
Polysaccharides such as polyethylene oxide, thermoplastic resins, polymers having rubber elasticity, and the like are used alone or as a mixture thereof. When a compound containing a functional group that reacts with lithium, such as a polysaccharide, is used, it is preferable to add a compound such as an isocyanate group to deactivate the functional group. The addition amount of the binder is preferably 1 to 50% by weight, particularly preferably 2 to 30% by weight. As the filler, any fibrous material that does not cause a chemical change in the configured battery can be used. Usually, fibers such as olefin-based polymers such as polypropylene and polyethylene, glass, and carbon are used. Although the amount of the filler is not particularly limited,
30% by weight is preferred.

When the negative electrode material of the present invention is used in a non-aqueous secondary battery system, an aqueous dispersion mixture paste containing the compound of the present invention is applied onto a current collector and dried, and the aqueous dispersion mixture paste is obtained. It is preferable that the pH is 5 or more and less than 10, more preferably 6 or more and less than 9. Further, it is preferable that the temperature of the aqueous dispersion paste is maintained at 5 ° C. or higher and lower than 80 ° C., and the application on the current collector is performed within 7 days after the preparation of the paste.

As the separator, a material having a large ion permeability, a predetermined mechanical strength, and insulating micropores or gaps is used. In order to further improve safety, it is necessary to have a function of closing the above gap at 80 ° C. or higher to increase resistance and cut off current. The closing temperature of these gaps is from 90 ° C to 180 ° C, more preferably from 110 ° C to 170 ° C. The method of forming the gap differs depending on the material, but may be any known method. In the case of a porous film, the shape of the holes is usually circular or elliptical, and the size is 0.05 μm to 30 μm, preferably 0.1 μm to 20 μm. Further, as in the case of the drawing method or the phase separation method, the holes may be rod-shaped or amorphous. In the case of cloth, the gap is a space between fibers, and depends on how to make a woven or nonwoven fabric. The ratio of closing of these gaps, that is, the porosity is from 20% to 90%,
35% to 80% is preferred.

The separator of the present invention has a thickness of 5 μm or more and 10
It is a microporous film, woven fabric, nonwoven fabric or the like having a thickness of 0 μm or less, more preferably 10 μm or more and 80 μm or less.
The separator of the present invention contains at least 2 ethylene components.
0% by weight is preferable, and 30% is particularly preferable.
The above is included. Examples of components other than ethylene include propylene, butene, hexene, fluorinated ethylene, vinyl chloride, vinyl acetate, and acetalized vinyl alcohol, and propylene and fluorinated ethylene are particularly preferable.
The microporous film is preferably made of polyethylene, an ethylene-propylene copolymer or an ethylene-butene copolymer. Further, those made by mixing and dissolving polyethylene and polypropylene and polyethylene and polytetrafluoroethylene are also preferable.

The non-woven fabric or woven fabric has a thread diameter of 0.1 μm to 5 μm and has polyethylene, ethylene-propylene copolymer, ethylene-butene 1 copolymer, ethylene-methylbutene copolymer, ethylene-methylpentene copolymer. A polymer, polypropylene, or polytetrafluoroethylene fiber system is preferable. These separators may be a single material or a composite material. In particular, two or more types of microporous films laminated with different pore sizes, porosities and pore blocking temperatures, microporous films and non-woven fabrics, microporous films and woven fabrics, and non-woven fabrics and papers with different forms of composite materials. What was done is especially preferable. The separator of the present invention may contain inorganic fibers such as glass fibers and carbon fibers, and particles of inorganic substances such as silicon dioxide, zeolite, alumina and talc. Further, the voids and the surface may be treated with a surfactant to make them hydrophilic.

The electrolyte is mainly composed of a solvent in which at least one kind or two or more kinds of aprotic organic solvents are mixed and a lithium salt which is soluble in the solvent. As these organic solvents, propylene carbonate, ethylene carbonate, butylene carbonate, dimethyl carbonate, diethyl carbonate, γ-butyrolactone, 1,
2-dimethoxyethane, tetrahydrofuran, 2-methyltetrahydrofuran, dimethylsulfoxide, 1,
3-dioxolane, formamide, dimethylformamide, dioxolane, acetonitrile, nitromethane, methyl formate, methyl acetate, methyl propionate, ethyl propionate, phosphate triester, trimethoxymethane, dioxolane derivative, sulfolane, 3-methyl-2
-Oxazolidinone, propylene carbonate derivative,
Tetrahydrofuran derivative, diethyl ether, 1,3
-Propane sultone etc. can be mentioned. Of these, carbonates are preferred, and propylene carbonate, ethylene carbonate, butylene carbonate, dimethyl carbonate, and diethyl carbonate are more preferred.

Examples of lithium salts soluble in these aprotic organic solvents include LiClO ₄ and LiB.
F ₄ , LiPF ₆ , LiCF ₃ SO ₃ , LiCF ₃ CO ₂ , L
iAs F ₆ , LiSbF ₆ , LiB ₁₀ Cl ₁₀ , lower aliphatic lithium carboxylate, LiAlCl ₄ , LiCl, L
Examples thereof include iBr, LiI, lithium chloroborane and lithium tetraphenylborate. Among these L
iClO ₄ , LiBF ₄ , LiPF ₆ , and LiCF ₃ SO ₃ are particularly preferable. Among them, a mixed solution of propylene carbonate or ethylene carbonate and 1,2-dimethoxyethane and / or diethyl carbonate is used to prepare Li.
An electrolyte containing CF ₃ SO ₃ , LiClO ₄ , LiBF ₄ and / or LiPF ₆ is preferred. A mixture of ethylene carbonate and diethyl carbonate was mixed with LiBF ₄ and
And / or an electrolyte containing LiPF ₆ is particularly preferred.

The amount of these electrolytes added to the battery is not particularly limited, but can be used in the required amount depending on the amount of the positive electrode active material or the negative electrode material and the size of the battery. The concentration of the supporting electrolyte is preferably 0.2 to 3 mol per liter of the electrolytic solution. The temperature for injecting the electrolytic solution is preferably in the range of -20 to 50 ° C, more preferably -20 to 40 ° C, and particularly preferably -10 to 30 ° C. It is preferable to cool both the electrolyte and the battery can during the injection.

In addition to the electrolytic solution, the following solid electrolytes can be used. Solid electrolytes are classified into inorganic solid electrolytes and organic solid electrolytes. Well-known inorganic solid electrolytes include nitrides, halides, and oxyacid salts of Li. Among them, Li ₃ N, LiI, Li ₅ NI
_{2, Li 3 N-LiI-} LiOH, LiSiO 4, Li S
_{iO 4 -LiI-LiOH, xLi 3} PO 4 - (1-x)
Li ₄ SiO ₄ , Li ₂ SiS ₃ , phosphorus sulfide compounds and the like are effective.

In the organic solid electrolyte, a polyethylene oxide derivative or a polymer containing the derivative, a polypropylene oxide derivative or a polymer containing the derivative, a polymer containing an ionic dissociative group, a mixture of the polymer containing an ionic dissociative group and the above aprotic electrolyte solution. A phosphoric acid ester polymer is effective. Furthermore, there is a method of adding polyacrylonitrile to the electrolytic solution. In addition, a method of using an inorganic and an organic solid electrolyte in combination is also known.

It is also known to add the following compounds to the electrolyte for the purpose of improving discharge and charge / discharge characteristics. For example, pyridine, triethylphosphite, triethanolamine, cyclic ether, ethylenediamine, n-glyme, hexaphosphoric triamide, nitrobenzene derivative, sulfur, quinonimine dye, N-substituted oxazolidinone and N, N'-substituted imidazolidinone,
Ethylene glycol dialkyl ether, quaternary ammonium salt, polyethylene glycol, pyrrole, 2-methoxyethanol, AlCl ₃ , monomer for conductive polymer electrode active material, triethylenephosphoramide, trialkylphosphine, morpholine, aryl having carbonyl group Examples thereof include compounds, hexamethylphosphoric triamide and 4-alkylmorpholine, bicyclic tertiary amines, oils (JP-A-62-287580), quaternary phosphonium salts, and tertiary sulfonium salts.

Further, in order to make the electrolytic solution nonflammable, a halogen-containing solvent such as carbon tetrachloride or ethylene trifluoride chloride can be contained in the electrolytic solution. In addition, carbon dioxide gas can be included in the electrolytic solution in order to provide suitability for high-temperature storage. Further, the mixture of the positive electrode and the negative electrode can contain an electrolytic solution or an electrolyte. For example, a method of including the ionic conductive polymer, nitromethane, and an electrolytic solution is known.

The current collectors for the positive and negative electrodes may be any electron conductor that does not cause a chemical change in the constructed battery. For example, for the positive electrode, stainless steel,
In addition to nickel, aluminum, titanium, carbon, etc., carbon, nickel,
What processed titanium or silver is used. Particularly, aluminum or an aluminum alloy is preferable. For the negative electrode, stainless steel, nickel,
In addition to copper, titanium, aluminum, carbon, and the like, copper, stainless steel, which is obtained by treating carbon, nickel, titanium, or silver on the surface, an Al—Cd alloy, or the like is used. Particularly, copper or a copper alloy is preferable. Oxidizing the surface of these materials is also used. In addition, it is desirable to make the current collector surface uneven by surface treatment. As the shape, in addition to a foil, a film, a sheet, a net, a punched material, a lath body, a porous body, a foamed body, a molded body of a fiber group, and the like are used. The thickness is not particularly limited.
Those having a thickness of up to 500 μm are used.

The shape of the battery can be any of coins, buttons, sheets, cylinders, flats, corners and the like. When the shape of the battery is a coin or a button, the mixture of the positive electrode active material and the negative electrode material is mainly used after being compressed into a pellet shape.
The thickness and diameter of the pellet are determined by the size of the battery. When the shape of the battery is a sheet, a cylinder, or a corner, the mixture of the positive electrode active material and the negative electrode material is mainly used after being applied (coated), dried, and compressed on the current collector. As a coating method, a general method can be used. For example,
Reverse roll method, direct roll method, blade method,
Knife method, extrusion method, curtain method, gravure method, bar method, dip method and squeeze method can be mentioned. Among them, a blade method, a knife method and an extrusion method are preferred. Application is 0.1-10
It is preferably carried out at a speed of 0 m / min. On this occasion,
By selecting the above-mentioned coating method in accordance with the solution physical properties and drying property of the mixture, a good surface state of the coated layer can be obtained. The coating may be performed on one side at a time or on both sides simultaneously. The application may be continuous, intermittent, or striped. The thickness, length and width of the coating layer are determined according to the size of the battery, and the thickness of the coating layer on one side is particularly preferably 1 to 2000 μm in a compressed state after drying.

As a method for drying or dehydrating the pellets or sheets, a generally adopted method can be used. In particular, it is preferable to use hot air, vacuum, infrared rays, far infrared rays, electron beams and low temperature air alone or in combination. The temperature is preferably in the range of 80 to 350 ° C, particularly 10 ° C.
A range from 0 to 250 ° C is preferred. The water content of the whole battery is preferably 2000 ppm or less, and the cathode mixture, the anode mixture and the electrolyte are preferably 500 ppm or less in terms of cycleability. The pellet and sheet pressing method is
Although a generally adopted method can be used, a die pressing method or a calendar pressing method is particularly preferable. The pressing pressure is not particularly limited, but 0.2 to 3 t / cm ² is preferable. The press speed of the calendar press method is 0.1 to 50.
m / min is preferable, and the pressing temperature is preferably room temperature to 200 ° C. The ratio of the width of the negative electrode sheet to that of the positive electrode sheet is 0.
9-1.1 are preferable and 0.95-1.0 is especially preferable. The content ratio between the positive electrode active material and the negative electrode material varies depending on the compound type and the mixture formulation, and thus cannot be limited. However, it can be set to an optimal value from the viewpoint of capacity, cycleability, and safety.

After being superposed on the mixture sheet via a separator, the sheets are rolled or folded and inserted into a can, the can and the sheet are electrically connected, and then an electrolytic solution is injected. A battery can is formed using the sealing plate. At this time, a safety valve can be used as a sealing plate. In addition to the safety valve, various conventionally known safety elements may be provided. For example, fuses,
A bimetal, a PTC element or the like is used. In addition to the safety valve, as a countermeasure against an increase in the internal pressure of the battery can, a method of cutting the battery can, a method of cracking a gasket, a method of cracking a sealing plate, or a method of cutting with a lead plate can be used. Further, the charger may be provided with a protection circuit incorporating measures for overcharging or overdischarging, or may be connected independently. As a measure against overcharging, a method of interrupting the current by increasing the internal pressure of the battery can be provided. At this time, a compound for increasing the internal pressure can be contained in the mixture or the electrolyte. Examples of compounds used to increase the internal pressure include Li ₂ CO ₃ , LiHCO ₃ , Na ₂ CO ₃ ,
Carbonates such as NaHCO ₃ , CaCO ₃ , MgCO ₃ and the like can be mentioned.

For the can and the lead plate, a metal or alloy having electrical conductivity can be used. For example, metals such as iron, nickel, titanium, chromium, molybdenum, copper, and aluminum or alloys thereof are used. Caps, cans,
Known methods (eg, DC or AC electric welding, laser welding, ultrasonic welding) can be used for welding the sheet and the lead plate. A conventionally known compound or mixture such as asphalt can be used as the sealing agent for closing.

The application of the non-aqueous secondary battery of the present invention is not particularly limited. For example, when it is installed in an electronic device, a color notebook computer, a black and white notebook computer, a pen input computer, a pocket (palmtop) computer, a notebook. Type word processor, pocket word processor, e-book player, mobile phone, cordless phone handset, pegger, handy terminal, mobile fax, mobile copy, mobile printer, headphone stereo, video movie, LCD TV, handy cleaner, portable CD, mini disk, Electric shaver, electronic translator, car phone,
Examples include a transceiver, a power tool, an electronic organizer, a calculator, a memory card, a tape recorder, a radio, a backup power supply, and a memory card. For other consumer use, automobiles, electric vehicles, motors, lighting equipment, toys,
Game devices, road conditioners, irons, watches, strobes, cameras, medical devices (pacemakers, hearing aids, shoulder massagers, etc.). Furthermore, it can be used for various military purposes and space applications. Further, it can be combined with a solar cell.

The preferred combination of the present invention is preferably a combination of the above-mentioned chemical materials and battery constituent parts, but especially Li _x CoO ₂ , Li as the positive electrode active material.
_{x N iO 2, Li x MnO} 2, Li x MnO 4 ( where x =
0.02-1.2), and at least one compound selected from the group including acetylene black as a conductive agent.

The positive electrode current collector is made of stainless steel or aluminum. It is shaped like a net, sheet, foil, lath, etc. As a negative electrode material, lithium metal, lithium alloy (Li-Al), carbonaceous compound, oxide (LiC
oVO ₄ , SnO ₂ , SnO, SiO, GeO ₂ , Ge
_{O, SnSiO 3, SnSi 0.3 Al} 0.1 B 0. 2 P 0.3 O 3.2
), Sulfide (TiS ₂ , SnS ₂ , SnS, GeS ₂ , G
It is preferable to use at least one compound containing eS) and the like. The negative electrode current collector is made of stainless steel or copper, and has a shape such as a net, a sheet, a foil, and a lath. The mixture used together with the positive electrode active material or the negative electrode material may be mixed with a carbon material such as acetylene black or graphite as an electron conductive agent. As the binder, a fluorine-containing thermoplastic compound such as polyvinylidene fluoride or polyfluoroethylene, a polymer containing acrylic acid, an elastomer such as styrene-butadiene rubber or ethylene propylene terpolymer can be used alone or in combination. Further, as an electrolytic solution, a combination of ethylene carbonate, a cyclic or acyclic carbonate such as diethyl carbonate or dimethyl carbonate, or an ester compound such as ethyl acetate, LiPF ₆ as a supporting electrolyte, and LiBF ₄ or LiCF ₃ SO It is preferable to use a mixture of lithium salts such as ₃ . Further, as the separator, polypropylene or polyethylene alone or a combination thereof is preferable. The form of the battery may be any of a cylinder, a flat type, and a square type. It is preferable that the battery is provided with means (for example, an internal pressure release type safety valve, a current cutoff type safety valve, and a separator that increases resistance at high temperatures) that can ensure safety against malfunction.

[0073]

The present invention will be described in more detail with reference to specific examples, but the present invention is not limited to the examples unless it exceeds the gist of the invention. SnB as in Example 1 a negative electrode material _{0.2 P 0.5 K 0.1 Mg 0.1 Ge} 0.1 O
86 parts by weight of _2.8 , acetylene black 3 as a conductive agent
By weight, 6 parts by weight of graphite were mixed, 4 parts by weight of polyvinylidene fluoride as a binder and 1 part by weight of carboxymethyl cellulose were further added, and the mixture was kneaded with water as a medium to obtain a negative electrode mixture slurry. The slurry was applied to both sides of a copper foil having a thickness of 10 μm using an extrusion coating machine and dried to obtain a negative electrode mixture sheet. Then α
Water was added as a medium to 88 parts by weight of alumina, 9 parts by weight of graphite, and 3 parts by weight of carboxymethyl cellulose and kneaded to obtain an auxiliary layer slurry. The slurry is applied onto the negative electrode mixture sheet, dried, and compression-molded by a calender press to have a thickness of 110 μm, a width of 55 mm, and a length of 520 mm.
A strip-shaped negative electrode sheet precursor of was prepared.

A nickel lead plate was spot-welded to the negative electrode sheet precursor, and then 2 in air with a dew point of -40 ° C or lower.
It was dehydrated and dried at 30 ° C. for 30 minutes. A 35 μm thick lithium foil (purity 99.8%) cut into 4 mm × 55 mm was stuck on the entire surface of this negative electrode mixture sheet at intervals of 10 mm at right angles to the length direction of the sheet. Further, the same lithium was attached to four portions of the portion where the lithium was not attached (intermediate portion of the stripe) in the non-positive portion in the lengthwise direction of the negative electrode sheet. At this time, the amount of lithium foil attached to the non-opposing portion is 220% of the amount of lithium attached to the opposing portion.
Met. 87 parts by weight of LiCoO ₂ as a positive electrode active material, 3 parts by weight of acetylene black as a conductive agent and 6 parts by weight of graphite were mixed, and N was added as a binder.
3 parts by weight of ipo1820B (manufactured by Nippon Zeon) and 1 part by weight of carboxymethylcellulose were added and kneaded with water as a medium to obtain a positive electrode mixture slurry.

The slurry was coated on both sides of an aluminum foil having a thickness of 20 μm by using an extrusion type coating machine, dried and then compression-molded by a calender press machine to form a belt-shaped member having a thickness of 190 μm, a width of 53 mm and a length of 445 mm. A positive electrode sheet (1) was prepared. After welding an aluminum lead plate to the end of the positive electrode sheet, the electrode sheet was dehydrated and dried at 230 ° C. for 30 minutes in dry air having a dew point of −40 ° C. or less. Heat-treated positive electrode sheet (1), microporous polyethylene / polypropylene film separator (3), negative electrode sheet (2)
And the separator (3) were laminated in this order, and this was spirally wound. The wound body was housed in a nickel-plated iron bottomed cylindrical battery can (4) also serving as a negative electrode terminal.
Further, 1 mol / liter LiPF ₆ (mixture of ethylene carbonate and diethyl carbonate in a weight ratio of 2 to 8) was injected as an electrolyte into the battery can while cooling the battery can to 0 ° C. A battery lid (5) having a positive electrode terminal was caulked via a gasket (6) to prepare a cylindrical battery (FIG. 1) having a height of 65 mm and an outer diameter of 18 mm (Battery A). The positive electrode terminal (5), the positive electrode sheet (1), and the battery can (4) were previously connected to the negative electrode sheet by lead terminals. (7) is a safety valve.

The prepared battery was opened at 0.2 A and the open circuit voltage was 3.0.
After charging to a constant current and constant voltage (CCCV) to V, it was stored in a constant temperature bath at 50 ° C. for 2 weeks. 4.1 A at 0.6 A after saving
CCCV was charged to V and then constant current discharge was performed to 0.6V at 2.8V. Then CC at 1.2A up to 4.1V
The battery capacity was obtained by CV charging and constant current discharge at 0.4 A to 2.8 V. CC up to 4.1V at 1.2A
A cycle test was performed under the conditions of CV charging and constant current discharging from 1.5 A to 2.8 V, and the capacity retention rate at the 300th cycle was obtained. The results are shown in Table 1.

Example-2 Example 1 was repeated except that the same 4 mm × 4 mm lithium foil was stuck between the stripes in the non-opposing part in the width direction with respect to the negative electrode sheet after the lithium was stuck prepared in Example 1. A battery B was prepared in exactly the same manner as.

Example 3 A battery C was prepared in exactly the same manner as in Example 1 except that the same lithium foil of 2 mm × 55 mm was stuck between the stripes of the positive electrode non-opposing part. Example-4 A battery D was prepared in exactly the same manner as in Example 1 except that a lithium foil cut into a size of 4 mm x 55 mm was stuck only between the stripes of the positive electrode non-opposing portion on the outermost surface on the innermost peripheral side of the negative electrode sheet. .

Comparative Example A battery a was prepared in exactly the same manner as in Example 1 except that the operation of sticking a large amount of lithium foil to the portion not facing the positive electrode was not performed. These batteries B to D and a were evaluated in the same manner as the battery A of Example-1. The results are shown in Table 1.

Table 1 Experimental Results Battery Excess Lithium Discharge Capacity Capacity Retention Rate Number Quantity (Note 1) (mAH) (%) A 220% 1710 86 B 250 1720 88 C 150 1680 84 D 130 1660 81 a 100 1620 76 Note 1 : Lithium amount per unit area of positive electrode non-facing part (to positive electrode facing part)

Example-5 Eight sheets (one side) of 20 μm thick lithium foil cut into 65 mm × 55 mm were attached to the negative electrode sheet prepared in Example 1 before attachment of lithium. Further, a 4 mm × 55 mm lithium foil was attached to four portions of the sheet in the length direction in which the positive electrode did not face each other. A battery E was produced in the same manner as in Example 1 except for this. Example-6 A lithium foil (thickness: 35 μ) cut into a frame shape of 8 mm × 6 mm was applied to the entire surface of the sheet at equal intervals of 40% with respect to the negative electrode sheet prepared in Example 1 before attachment of lithium. I put it on. Further, a 4 mm x 5 mm frame-shaped lithium foil was applied to the four non-opposing portions of the positive electrode in the longitudinal direction of the sheet, and the coverage of the non-opposing portion was 8
It was stuck so that it would be 0%. A battery F was prepared in the same manner as in Example 1 except for this. Comparative Example-2 A battery b was prepared in exactly the same manner as in Example 5 except that the operation of increasing the amount of lithium in the non-opposing portion of Example 5 was not performed. Comparative Example-3 A battery c was prepared in exactly the same manner as in Example 5 except that the lithium amount in the non-opposing portion of Example 6 was not increased. The batteries E, F, b, and c were evaluated for battery capacity and cycle characteristics in exactly the same manner as the battery A of Example 1. The results are shown in Table 2.

Table 2 Experimental Results Battery Excess Lithium Discharge Capacity Capacity Maintenance Rate Number Quantity (Note 1) (mAH) (%) E 200% 1775 82 b 100 1700 74 F 155 1750 85 c 100 1690 76

[0083]

As is clear from the results of Tables 1 and 2, the battery of the present invention has a larger amount of lithium attached to the positive electrode non-opposing portion of the negative electrode sheet than the lithium amount attached to the positive electrode opposing portion. Large discharge capacity and excellent cycleability.

[0084]

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a general cylindrical battery.

[Explanation of symbols]

 1. 1. positive electrode Negative electrode 3. Separator 4. Battery can 5. Battery cover 6. Gasket 7. safety valve

Claims (6)

[Claims] 1. A positive electrode sheet having a layer mainly composed of a lithium-containing transition metal oxide, a layer mainly composed of a metal or metalloid oxide, and at least one auxiliary layer containing water-insoluble conductive particles. In a non-aqueous secondary battery composed of a negative electrode sheet, a non-aqueous electrolyte containing a lithium salt and a separator, the mixture application portion of the negative electrode sheet is longer than the positive electrode sheet facing in both the length direction and the width direction of the sheet, The negative electrode sheet is made by stacking a metallic material mainly containing lithium on a mixture, and the unit of the metallic material is laminated on a negative electrode mixture sheet which does not face at least one positive electrode. The weight per area is 10% or more and 400% or more than the weight per unit area of the metal material laminated on the negative electrode mixture sheet facing the positive electrode.
A non-aqueous secondary battery characterized by having a large number below. 2. The pattern for laminating a metallic material containing lithium as a main component on the negative electrode sheet is at least one kind of a whole surface, a stripe shape, a frame shape, and a disc shape. Non-aqueous secondary battery 3. A method of stacking a large amount of a metal material mainly containing lithium on a negative electrode material mixture sheet not facing the positive electrode at least at one place on a negative electrode material mixture sheet facing the positive electrode per unit area. 3. The method according to claim 1 or 2, wherein the method is performed by making the intervals between the overlapping pieces of the metal material more dense and / or by increasing the thickness of the metal material. Non-aqueous secondary battery. 4. The thickness of the lithium-based metal material is 5 to 150 μm.
The non-aqueous secondary battery according to any one of the above items. 5. The non-aqueous secondary battery according to claim 1, wherein the negative electrode sheet has a coverage of a metallic material mainly containing lithium of 10 to 100%. . 6. The non-aqueous secondary battery according to claim 1, wherein the negative electrode is a composite oxide containing tin.