WO2018025594A1 - All-solid-state lithium battery - Google Patents

Abstract

Provided is an all-solid-state lithium battery having greatly improved cycle performance when charging and discharging are repeatedly performed. The all-solid-state lithium battery according to the present invention is provided with: an oriented positive electrode plate having a thickness of 30 μm or more and constituted of an oriented sintered body; a solid-state electrolyte layer disposed on the oriented positive electrode plate and constituted of a lithium ion conducting material; and an intermediate layer having a thickness of 0.001-1 μm disposed on the solid-state electrolyte layer and comprising a metal capable of forming an alloy with lithium. In the oriented positive electrode plate, the oriented sintered body comprises a plurality of primary particles constituted of a lithium composite oxide having a layered rock salt structure, and the plurality of primary particles are oriented at an average orientation angle of over 0° and 30° or less with respect to the plate surface of the oriented positive electrode plate.

Description

All solid lithium battery

The present invention relates to an all solid lithium battery.

2. Description of the Related Art Conventionally, in a battery used for a portable device such as a personal computer or a mobile phone, a liquid electrolyte (electrolytic solution) in which a lithium salt is dissolved in a flammable organic solvent is used as a medium for moving ions. Conventionally used. A battery using such an electrolytic solution may cause problems such as leakage of the electrolytic solution, ignition, and explosion. In order to solve these problems, in order to ensure essential safety, the development of an all-solid-state lithium battery in which a solid electrolyte is used instead of a liquid electrolyte and all other elements are made of solid is progressed. It has been. Such an all-solid-state lithium battery has a solid electrolyte, so there is little fear of ignition, no leakage, and problems such as deterioration of battery performance due to corrosion hardly occur.

For example, Patent Document 1 (International Publication No. 2017/006591) discloses an alignment positive electrode plate made of a lithium composite oxide such as lithium cobaltate (LiCoO ₂ ) and a lithium phosphate oxynitride glass electrolyte (LiPON). An all-solid-state lithium battery including a solid electrolyte layer made of a lithium ion conductive material such as) and a negative electrode layer made of lithium metal is disclosed. In addition, in this document, by interposing an intermediate layer containing a metal that can be alloyed with lithium between the solid electrolyte layer and the negative electrode layer, it is possible to prevent internal short circuit and peeling of the negative electrode layer due to the reflow soldering process. Are listed.

By the way, the positive electrode active material composed of a lithium composite oxide having a layered rock salt structure has an arbitrary diffusion plane in the plane of the (003) plane (that is, in a plane parallel to the (003) plane). It is known that lithium ions enter and exit in crystal planes other than the (003) plane (for example, (101) plane or (104) plane). Therefore, in this type of positive electrode active material, a surface that comes into contact with the electrolyte more in a crystal plane (a plane other than the (003) plane, for example, the (101) plane or the (104) plane) on which lithium ions can enter and exit satisfactorily. Attempts have been made to improve the battery characteristics of lithium secondary batteries by exposing them to the above. In fact, also in the above-described Patent Document 1, the lithium transition metal oxide particles are oriented so that the (003) plane intersects the plate surface of the oriented positive electrode plate, so that a plane other than the (003) plane (for example, (101) ) Plane and (104) plane) are disclosed.

International Publication No. 2017/006591

As far as the present inventors know, the conventional oriented positive electrode plate as disclosed in Patent Document 1 generally has the primary particles oriented such that the (003) plane is inclined by 45 to 75 ° with respect to the plate surface. Is. In other words, the conventional oriented positive electrode plate is designed according to the concept that it is better to expose as many surfaces as possible to the entry and exit of lithium ions (for example, the (101) plane and the (104) plane). However, an all-solid lithium battery as disclosed in Patent Document 1 employing such a conventional oriented positive electrode plate is short-circuited locally when a long-term cycle test is performed or when it is operated at a high temperature. May occur and the cycle performance may deteriorate. This is because the orientation positive electrode plate in which the primary particles are oriented at the angles as described above tends to cause expansion and contraction during charge and discharge in the direction parallel to the plate surface of the orientation positive electrode plate, and therefore stress is applied to the interface with the fixed electrolyte layer. It is because it is easy to generate. This interfacial stress can cause defects in the solid electrolyte layer and sometimes cause a local short circuit, resulting in degradation of cycle performance and battery failure.

The present inventors have recently adopted an oriented positive electrode plate in which a plurality of primary particles are oriented at an average orientation angle of more than 0 ° and not more than 30 ° with respect to the plate surface of the oriented positive electrode plate, and the oriented positive electrode of the solid electrolyte layer It was found that by providing a predetermined intermediate layer on the surface opposite to the plate (that is, the surface on the negative electrode side), it is possible to provide an all-solid-state lithium battery with greatly improved cycle performance when repeated charge and discharge are performed. .

Therefore, an object of the present invention is to provide an all-solid-state lithium battery with greatly improved cycle performance when charging and discharging are repeated.

According to one aspect of the present invention, there is provided an oriented positive electrode plate having a thickness of 30 μm or more constituted by an oriented sintered body, wherein the oriented sintered body comprises a plurality of lithium composite oxides having a layered rock salt structure. An oriented positive electrode plate comprising primary particles, wherein the plurality of primary particles are oriented at an average orientation angle of more than 0 ° and not more than 30 ° with respect to the plate surface of the oriented positive electrode plate;
A solid electrolyte layer provided on the oriented positive electrode plate and made of a lithium ion conductive material;
An intermediate layer provided on the solid electrolyte layer and containing a metal that can be alloyed with lithium and having a thickness of 0.001 to 1 μm;
An all-solid lithium battery is provided.

It is a schematic cross section which shows an example of the all-solid-state lithium battery of this invention. It is a model top view of the all-solid-state lithium battery shown by FIG. It is a schematic cross section which shows another example of the all-solid-state lithium battery of this invention. It is a schematic cross section which shows another example of the all-solid-state lithium battery of this invention. It is a schematic cross section for conceptually explaining the lithium ion conduction direction and the expansion / contraction method of the lithium composite oxide primary particles contained in the oriented positive electrode plate of the present invention. It is a schematic cross section for conceptually explaining a lithium ion conduction direction and an expansion / contraction method in an example of a conventional oriented positive electrode plate. FIG. 8 is a schematic cross-sectional view for conceptually explaining the lithium ion conduction direction and the expansion / contraction method in the oriented positive electrode plate used in the present invention as shown in FIG. 7. It is a SEM image which shows an example of a cross section perpendicular | vertical to the plate | board surface of an orientation positive electrode plate. It is an EBSD image in the cross section of the orientation positive electrode plate shown by FIG. 10 is a histogram showing the distribution of primary particle orientation angles in the EBSD image of FIG. 9 on an area basis.

All Solid Lithium Battery FIGS. 1 and 2 schematically show an example of an all solid lithium battery according to the present invention. The all solid lithium battery 10 shown in FIGS. 1 and 2 includes an oriented positive electrode plate 12, a solid electrolyte layer 14, an intermediate layer 15, and optionally a negative electrode layer 16. The all-solid lithium battery 10 shown in FIG. 1 includes two unit batteries each composed of an oriented positive electrode plate 12, an intermediate layer 13, a solid electrolyte layer 14, an intermediate layer 15, a negative electrode layer 16, and a positive electrode current collector 20. It has a configuration in which the negative electrode current collector 24 is laminated in parallel vertically symmetrically. However, the present invention is not limited to this, and may be configured by one unit cell 10 ′ as schematically shown in FIG. 3, or may be configured by stacking two or more unit cells in parallel or in series. Also good. The oriented positive plate 12 is a plate having a thickness of 30 μm or more constituted by an oriented sintered body, and the oriented sintered body includes a plurality of primary particles constituted by a lithium composite oxide having a layered rock salt structure. The plurality of primary particles are oriented at an average orientation angle of more than 0 ° and not more than 30 ° with respect to the plate surface of the oriented positive electrode plate. The average orientation angle is an average value of inclination angles formed by the (003) planes of the primary particles with respect to the plate surface direction. The solid electrolyte layer 14 is made of a lithium ion conductive material and is provided on the oriented positive electrode plate 12. The intermediate layer 15 is a layer having a thickness of 0.001 to 1 μm containing a metal that can be alloyed with lithium, and is provided on the solid electrolyte layer 14. Thus, (i) the oriented positive electrode plate 12 in which a plurality of primary particles are oriented at an average orientation angle of more than 0 ° and not more than 30 ° with respect to the plate surface of the oriented positive electrode plate 12, and (ii) a solid electrolyte is employed. By providing a predetermined intermediate layer on the surface of the layer 14 opposite to the oriented positive electrode plate 12 (that is, the surface on the negative electrode side), an all-solid lithium battery with greatly improved cycle performance upon repeated charge and discharge is provided. can do. This can be explained as follows.

(I) Reduction of short-circuit by an alignment positive electrode plate having an average alignment angle of more than 0 ° and less than 30 ° In the all solid lithium battery 10 of the present invention, a plurality of primary particles are more than 0 ° and 30 ° with respect to the plate surface of the alignment positive electrode plate 12. By employing the oriented positive electrode plate 12 oriented at the following average orientation angle, the stress that can be generated at the interface with the fixed electrolyte layer can be reduced, and short circuit defects can be eliminated. Specifically, it is considered as follows. The layered rock salt structure lithium composite oxide constituting the primary particles has the property that the interlayer distance increases as lithium ions are released. That is, as conceptually shown in FIG. 5, the primary particles 11 of the lithium composite oxide have a lithium ion movement direction LiD parallel to the (003) plane and an expansion / contraction direction ECD perpendicular to the (003) plane. is doing. Therefore, as shown in FIG. 6, in the conventional oriented positive electrode plate 12 ′ in which the primary particles are oriented so that the (003) plane is inclined by 45 to 75 ° with respect to the plate surface, a plurality of primary particles 11 are formed. The expansion / contraction causes expansion / contraction in the direction parallel to the plate surface of the oriented positive electrode plate 12 ′ as a whole, that is, the expansion / contraction direction ECD is parallel to the plate surface. In contrast, the oriented positive electrode plate 12 employed in the present invention has an average orientation angle of primary particles, that is, an average orientation angle of the (003) plane of more than 0 ° and 30 °, as conceptually depicted in FIG. By becoming below, the expansion | swelling of the surface direction of the orientation positive electrode plate 12 accompanying lithium ion detachment | miniaturization becomes small. For this reason, the tensile stress to the solid electrolyte layer 14 due to the expansion and contraction of the oriented positive electrode plate 12 at the time of charging / discharging is reduced, and an electrical short circuit or an increase in resistance due to the breakage or peeling of the solid electrolyte layer 14 or the occurrence of cracks is prevented. Can lead to improved cycle characteristics.

(Ii) Improving cycle performance by homogenizing resistance with intermediate layer However, when an oriented positive electrode plate with an average orientation angle of more than 0 ° and less than 30 ° is adopted, another problem is that the resistance value tends to vary depending on the in-plane position. Can happen. This variation in resistance value is caused when lithium is easily deposited on the surface opposite to the orientation positive electrode plate 12 of the solid electrolyte layer 14 (that is, the surface on the negative electrode side), particularly when charging / discharging at high speed. It is possible to cause a difficult portion, and the cycle performance when charging / discharging is repeated (especially at a high rate) can be reduced. This is because the orientation positive electrode plate having an average orientation angle of more than 0 ° and not more than 30 ° is not only a lithium ion entrance / exit surface (for example, (101) surface or (104) surface) but also lithium ion as understood from FIG. This is because the (003) surface where ions do not enter and exit is significantly exposed on the negative electrode side surface of the solid electrolyte layer 14. That is, lithium is likely to precipitate on the exposed surface of the entry / exit surface of lithium ions (for example, (101) surface or (104) surface), while lithium is difficult to precipitate on the exposed portion of the (003) surface where lithium ions do not enter or exit. In particular, in the all solid lithium battery in which the energy density is increased by employing an oriented positive plate having a thickness of 30 μm or more as in the present invention, the above problem becomes more conspicuous because the absolute amount of lithium is large. In this regard, in the all-solid-state lithium battery 10 of the present invention, the above problem is solved by providing an intermediate layer 15 having a thickness of 0.001 to 1 μm containing a metal that can be alloyed with lithium on the solid electrolyte layer 14. Thus, the cycle performance when charging / discharging is repeated (especially at a high rate) can be greatly improved. This is considered due to the fact that the intermediate layer 15 homogenizes the resistance of the solid electrolyte layer 14 that affects lithium deposition in the in-plane direction.

Oriented positive electrode plate The oriented positive electrode plate 12 is a plate having a thickness of 30 μm or more formed of an oriented sintered body. The oriented sintered body includes a plurality of primary particles composed of a lithium composite oxide having a layered rock salt structure, and the plurality of primary particles has an average orientation angle of more than 0 ° and not more than 30 ° with respect to the plate surface of the oriented positive electrode plate. Is oriented. FIG. 8 shows an example of a cross-sectional SEM image perpendicular to the plate surface of the alignment positive electrode plate 12, while FIG. 9 shows an electron backscatter diffraction (EBSD) image in a cross section perpendicular to the plate surface of the alignment positive electrode plate 12. Indicates. FIG. 10 is a histogram showing the orientation angle distribution of the primary particles 11 in the EBSD image of FIG. In the EBSD image shown in FIG. 9, discontinuity of crystal orientation can be observed. In FIG. 9, the orientation angle of each primary particle 11 is shown in shades of color, and the darker the color, the smaller the orientation angle. The orientation angle is an inclination angle formed by the (003) plane of each primary particle 11 with respect to the plate surface direction. In FIGS. 8 and 9, the portions displayed in black inside the aligned positive electrode plate 12 are pores.

The oriented positive electrode plate 12 is an oriented sintered body composed of a plurality of primary particles 11 bonded to each other. Each primary particle 11 is mainly plate-shaped, but may include particles formed in a rectangular parallelepiped shape, a cubic shape, a spherical shape, or the like. The cross-sectional shape of each primary particle 11 is not particularly limited, and may be a rectangle, a polygon other than a rectangle, a circle, an ellipse, or a complex shape other than these.

Each primary particle 11 is composed of a lithium composite oxide. The lithium composite oxide is Li _x MO ₂ (0.05 <x <1.10, M is at least one transition metal, and M is typically one or more of Co, Ni, and Mn. It is an oxide represented by. The lithium composite oxide has a layered rock salt structure. The layered rock salt structure is a crystal structure in which lithium layers and transition metal layers other than lithium are alternately stacked with oxygen layers in between, that is, the transition metal ion layer and the lithium single layer are alternately arranged via oxide ions. It refers to a laminated crystal structure (typically an α-NaFeO ₂ type structure, ie, a structure in which transition metals and lithium are regularly arranged in the [111] axis direction of a cubic rock salt type structure). Examples of the lithium composite oxide include Li _x CoO ₂ (lithium cobaltate), Li _x NiO ₂ (lithium nickelate), Li _x MnO ₂ (lithium manganate), Li _x NiMnO ₂ (nickel / lithium manganate) , Li _x NiCoO ₂ (nickel / lithium cobaltate), Li _x CoNiMnO ₂ (cobalt / nickel / lithium manganate), Li _x CoMnO ₂ (cobalt / lithium manganate), and the like, particularly preferably Li _x CoO _2. (Lithium cobaltate, typically LiCoO ₂ ). The lithium composite oxide includes Mg, Al, Si, Ca, Ti, V, Cr, Fe, Cu, Zn, Ga, Ge, Sr, Y, Zr, Nb, Mo, Ag, Sn, Sb, Te, Ba One or more elements selected from Bi, Bi, and W may be included.

9 and 10, the average value of the orientation angles of the primary particles 11, that is, the average orientation angle is more than 0 ° and not more than 30 °. This provides the following various advantages. First, since each primary particle 11 is in a state of lying in a direction inclined with respect to the thickness direction, the adhesion between the primary particles can be improved. As a result, since the lithium ion conductivity between a certain primary particle 11 and other primary particles 11 adjacent to both sides in the longitudinal direction of the primary particle 11 can be improved, rate characteristics can be improved. Secondly, as described above with reference to FIGS. 4 and 5, the cycle characteristics can be improved. That is, when each primary particle 11 expands and contracts in the direction perpendicular to the (003) plane in accordance with the entry and exit of lithium ions, the orientation positive electrode in the plate plane direction is reduced by reducing the inclination angle of the (003) plane with respect to the plate plane direction. The expansion / contraction amount of the plate 12 is reduced, and it is possible to suppress the occurrence of stress between the oriented positive electrode plate 12 and the solid electrolyte layer 14. Third, rate characteristics can be further improved. As described above, when the lithium ion enters and exits, in the alignment positive electrode plate 12, the expansion / contraction in the thickness direction is more dominant than the plate surface direction, so that the expansion / contraction of the alignment positive electrode plate 12 becomes smooth. This is because lithium ions can go in and out smoothly.

The average orientation angle of the primary particles 11 can be obtained by the following method. First, in an EBSD image obtained by observing a 95 μm × 125 μm rectangular region as shown in FIG. 9 at a magnification of 1000 times, three horizontal lines that equally divide the alignment positive electrode plate 12 in the thickness direction, and the alignment positive electrode plate 12 Draw three vertical lines that equally divide the Next, the average orientation angle of the primary particles 11 is obtained by arithmetically averaging the orientation angles of all the primary particles 11 intersecting at least one of the three horizontal lines and the three vertical lines. The average orientation angle of the primary particles 11 is preferably 30 ° or less, more preferably 25 ° or less, from the viewpoint of further improving the rate characteristics. The average orientation angle of the primary particles 11 is preferably 2 ° or more, more preferably 5 ° or more, from the viewpoint of further improving the rate characteristics.

As shown in FIG. 10, the orientation angle of each primary particle 11 may be widely distributed from 0 ° to 90 °, but most of it is distributed in a region of more than 0 ° and not more than 30 °. Is preferred. That is, the oriented sintered body constituting the oriented positive electrode plate 12 has an orientation angle with respect to the plate surface of the oriented positive electrode plate 12 of the primary particles 11 included in the analyzed cross section when the cross section is analyzed by EBSD. The total area of primary particles 11 (hereinafter referred to as low-angle primary particles) having an angle of 30 ° or less is included in the cross section of primary particles 11 (specifically, 30 primary particles 11 used for calculating the average orientation angle). The total area is preferably 70% or more, more preferably 80% or more. Thereby, since the ratio of the primary particle 11 with high mutual adhesiveness can be increased, rate characteristics can be further improved. The total area of the low-angle primary particles having an orientation angle of 20 ° or less is more preferably 50% or more with respect to the total area of the 30 primary particles 11 used for calculating the average orientation angle. . Furthermore, the total area of the low-angle primary particles having an orientation angle of 10 ° or less is more preferably 15% or more with respect to the total area of the 30 primary particles 11 used for calculating the average orientation angle. .

Since each primary particle 11 is mainly plate-shaped, the cross-section of each primary particle 11 extends in a predetermined direction as shown in FIGS. 8 and 9, and typically has a substantially rectangular shape. That is, when the cross section of the oriented sintered body is analyzed by EBSD, the total area of the primary particles 11 having an aspect ratio of 4 or more among the primary particles 11 included in the analyzed cross section is included in the cross section. The total area of the particles 11 (specifically, 30 primary particles 11 used for calculating the average orientation angle) is preferably 70% or more, more preferably 80% or more. Specifically, in the EBSD image as shown in FIG. 9, the mutual adhesion between the primary particles 11 can be further improved, and as a result, the rate characteristics can be further improved. The aspect ratio of the primary particles 11 is a value obtained by dividing the maximum ferret diameter of the primary particles 11 by the minimum ferret diameter. The maximum ferret diameter is the maximum distance between the straight lines when the primary particle 11 is sandwiched between two parallel straight lines on the EBSD image when the cross section is observed. The minimum ferret diameter is the minimum distance between the straight lines when the primary particle 11 is sandwiched between two parallel lines on the EBSD image.

The average particle size of the plurality of primary particles constituting the oriented sintered body is preferably 5 μm or more. Specifically, the average particle diameter of the 30 primary particles 11 used for calculating the average orientation angle is preferably 5 μm or more, more preferably 7 μm or more, and further preferably 12 μm or more. Thereby, since the number of grain boundaries between the primary particles 11 in the direction in which lithium ions are conducted is reduced and the lithium ion conductivity as a whole is improved, the rate characteristics can be further improved. The average particle diameter of the primary particles 11 is a value obtained by arithmetically averaging the equivalent circle diameters of the primary particles 11. The equivalent circle diameter is the diameter of a circle having the same area as each primary particle 11 on the EBSD image.

The density of the oriented sintered body constituting the oriented positive electrode plate 12 is preferably 70% or more, more preferably 80% or more, and further preferably 90% or more. Thereby, since the mutual adhesiveness of primary particles 11 can be improved more, a rate characteristic can be improved more. The denseness of the oriented sintered body is calculated by binarizing the obtained SEM image by observing the cross section of the positive electrode plate by CP (cross section polisher) polishing and then SEM observation at 1000 magnifications. The average equivalent circle diameter of each pore formed inside the oriented sintered body is not particularly limited, but is preferably 8 μm or less. As the average equivalent circle diameter of each pore is smaller, the mutual adhesion between the primary particles 11 can be further improved, and as a result, the rate characteristics can be further improved. The average equivalent circle diameter of the pores is a value obtained by arithmetically averaging the equivalent circle diameters of the ten pores on the EBSD image. The equivalent circle diameter is the diameter of a circle having the same area as each pore on the EBSD image. Each pore formed inside the oriented sintered body may be an open pore connected to the outside of the oriented positive plate 12, but preferably does not penetrate the oriented positive plate 12. Each pore may be a closed pore.

The thickness of the alignment positive electrode plate 12 is 30 μm or more, preferably 40 μm or more, particularly preferably 50 μm or more, from the viewpoint of improving the energy density of the all-solid lithium battery 10 by increasing the active material capacity per unit area. Preferably it is 55 micrometers or more. Although the upper limit value of the thickness is not particularly limited, the thickness of the alignment positive electrode plate 12 is preferably less than 200 μm, more preferably from the viewpoint of suppressing deterioration of battery characteristics (particularly increase in resistance value) due to repeated charge and discharge. It is 150 μm or less, more preferably 120 μm or less, particularly preferably 100 μm or less, most preferably 90 μm or less, 80 μm or less, or 70 μm or less. Further, the size of the oriented positive electrode plate is preferably 5 mm × 5 mm square or more, more preferably 10 mm × 10 mm to 200 mm × 200 mm square, and further preferably 10 mm × 10 mm to 100 mm × 100 mm square. if, preferably 25 mm ² or more, more preferably 100 ~ 40000 mm ^2, more preferably from 100 ~ 10000 mm ^2.

The oriented positive electrode plate 12 may include a conductive film 12a having a thickness of 0.01 μm or more and less than 5 μm on the surface opposite to the solid electrolyte layer 14 (that is, the surface on the positive electrode current collector 20 side). By carrying out like this, the electronic conductivity of the positive electrode electrical power collector 20 and the orientation positive electrode plate 12 can be improved, and the contact resistance in an interface can be reduced further. The conductive film 12a is preferably made of metal and / or carbon. When the conductive film 12a is made of a metal, the conductive film 12a has a low electron conduction resistance with the positive electrode current collector 20 and the alignment positive electrode plate 12 and is a layer made of a metal that does not adversely affect the characteristics of the alignment positive electrode plate 12, in particular. Although not limited, preferred examples include an Au sputtered layer and a Si sputtered layer. A carbon layer may be used instead of a metal conductive film such as an Au sputter layer. The thickness of the conductive film 12a is 0.01 μm or more and less than 5 μm, preferably 0.02 μm or more and 2 μm or less, more preferably 0.02 μm or more and 1 μm or less, and further preferably 0.04 μm or more and 1 μm or less.

Solid electrolyte layer The lithium ion conductive material constituting the solid electrolyte layer 14 is a garnet-based ceramic material, a nitride-based ceramic material, a perovskite-based ceramic material, a phosphate-based ceramic material, a sulfide-based ceramic material, or a lithium-chloride-based material. Or at least one selected from the group consisting of garnet-based ceramic materials, nitride-based ceramic materials, perovskite-based ceramic materials, and phosphate-based ceramic materials. is there. Examples of garnet based ceramic materials include Li—La—Zr—O based materials (specifically, Li ₇ La ₃ Zr ₂ O ₁₂ etc.), Li—La—Ta—O based materials (specifically, Li ₇ La ₃ Ta ₂ O ₁₂ etc.). An example of a nitride ceramic material is Li ₃ N. Examples of perovskite ceramic materials include Li—La—Zr—O based materials (specifically, LiLa _1-x Ti _x O ₃ (0.04 ≦ x ≦ 0.14), etc.). Examples of phosphate ceramic materials include lithium phosphate, nitrogen-substituted lithium phosphate (LiPON), Li—Al—Ti—PO, Li—Al—Ge—PO, and Li—Al—Ti—. Si—P—O (specifically, Li _{1 + x + y} Al _x Ti _2−x Si _y P _3−y O ₁₂ (0 ≦ x ≦ 0.4, 0 <y ≦ 0.6), etc.) may be mentioned.

It is particularly preferable that the lithium ion conductive material constituting the solid electrolyte layer 14 is composed of a Li—La—Zr—O based ceramic material and / or a lithium phosphate oxynitride (LiPON) based ceramic material. The Li—La—Zr—O-based material is an oxide sintered body having a garnet-type or garnet-type similar crystal structure including Li, La, Zr, and O. Specifically, Li ₇ It is a garnet-based ceramic material such as La ₃ Zr ₂ O ₁₂ , and details thereof are disclosed in Patent Document 1, for example. A lithium phosphate oxynitride (LiPON) ceramic material is also preferable. LiPON is a group of compounds represented by the composition of Li _2.9 PO _3.3 N _0.46 . For example, Li _a PO _b N _c (wherein a is 2 to 4 and b is 3 to 5 , C is 0.1 to 0.9).

The dimensions of the solid electrolyte layer 14 are not particularly limited, but the thickness is preferably 0.0005 mm to 0.1 mm, more preferably 0.001 mm to 0.05 mm, and still more preferably, from the viewpoint of charge / discharge rate characteristics and mechanical strength. Is 0.002 to 0.02 mm, particularly preferably 0.003 to 0.01 mm.

As a method for forming the solid electrolyte layer 14, various particle jet coating methods, solid phase methods, solution methods, and gas phase methods can be used. Examples of the particle jet coating method include an aerosol deposition (AD) method, a gas deposition (GD) method, a powder jet deposition (PJD) method, a cold spray (CS) method, and a thermal spraying method. Among these, the aerosol deposition (AD) method is particularly preferable because it can form a film at room temperature, and does not cause a composition shift in the process or formation of a high resistance layer by reaction with an oriented positive electrode plate. Examples of the solid phase method include a tape lamination method and a printing method. Among these, the tape lamination method is preferable because the solid electrolyte layer 14 can be formed thin and the thickness can be easily controlled. Examples of the solution method include a solvothermal method, a hydrothermal synthesis method, a sol-gel method, a precipitation method, a microemulsion method, and a solvent evaporation method. Among these methods, the hydrothermal synthesis method is particularly preferable in that it is easy to obtain crystal grains having high crystallinity at a low temperature. In addition, microcrystals synthesized using these methods may be deposited on the positive electrode or may be directly deposited on the positive electrode. Examples of the gas phase method include laser deposition (PLD) method, sputtering method, evaporation condensation (PVD) method, gas phase reaction method (CVD) method, vacuum deposition method, molecular beam epitaxy (MBE) method and the like. Among these, the sputtering method is particularly preferable because there is little composition deviation and a film with relatively high adhesion can be easily obtained.

The interface between the oriented positive electrode plate 12 and the solid electrolyte layer 14 may be subjected to a treatment for reducing the interface resistance. For example, such treatment includes niobium oxide, titanium oxide, tungsten oxide, tantalum oxide, lithium-nickel composite oxide, lithium-titanium composite oxide, lithium-niobium compound, lithium-tantalum compound, lithium- This can be done by coating the surface of the oriented positive electrode plate 12 and / or the surface of the solid electrolyte layer 14 with a tungsten compound, a lithium / titanium compound, and any combination or composite oxide thereof. By such treatment, a coating film can exist at the interface between the oriented positive electrode plate 12 and the solid electrolyte layer 14, but the thickness of the coating film is extremely thin, for example, 20 nm or less.

The intermediate layer 15 is a layer having a thickness of 0.001 to 1 μm containing a metal that can be alloyed with lithium, and is provided on the surface of the solid electrolyte layer 14 opposite to the oriented positive electrode plate 12 (that is, the surface on the negative electrode side). It is done. Metals that can be alloyed with lithium are Al (aluminum), Si (silicon), Zn (zinc), Ga (gallium), Ge (germanium), Ag (silver), Au (gold), Pt (platinum), Cd. It is preferable to include at least one selected from the group consisting of (cadmium), In (indium), Sn (tin), Sb (antimony), Pb (lead), and Bi (bismuth), and more preferably Au ( It contains at least one selected from the group consisting of gold), Si (silicon), Sn (tin), Al (aluminum), and Bi (bismuth). The intermediate layer may be formed by a known method such as an aerosol deposition (AD) method, a pulse laser deposition (PLD) method, a sputtering method, or an evaporation method. The dimension of the intermediate layer is not particularly limited, but the thickness is 0.001 to 1 μm, preferably 0.001 to 0.5 μm, more preferably 0.001 to 0.1 μm, from the viewpoint of homogenizing resistance. Particularly preferred is 0.003 to 0.03 μm.

The negative electrode layer all solid lithium battery 10 typically further includes a negative electrode layer 16 on the intermediate layer 15. However, the all solid lithium battery 10 of the present invention can operate without the negative electrode layer 16. This is because the lithium metal deposited on the intermediate layer 15 during charging can also be used as the negative electrode active material. The negative electrode layer 16 is a layer containing lithium and is typically made of lithium metal. The negative electrode layer 16 may be produced by placing a lithium metal in the form of a foil on the intermediate layer 15 or the negative electrode current collector 24, or a thin film of lithium metal on the intermediate layer 15 or the negative electrode current collector 24. May be formed by forming a lithium metal layer by vacuum deposition, sputtering, CVD, or the like. The dimensions of the negative electrode layer 16 are not particularly limited, but the thickness is preferably 10 μm or more, more preferably 50 to 10 μm, from the viewpoint of securing a large amount of lithium in the all-solid lithium battery 10 with the adoption of the thick oriented positive electrode plate 12. More preferably, it is 40 to 10 μm, particularly preferably 20 to 10 μm.

If desired, the end insulating portion 18 may be provided so as to insulate the end portion of the solid electrolyte layer 14. The end insulating portion 18 preferably includes an organic polymer material that can be adhered or adhered to the solid electrolyte layer 14. By including the organic polymer material in the end insulating portion 18, it is possible to more effectively realize prevention of short circuit between the oriented positive electrode plate 12 and the negative electrode layer 16. The organic polymer material is preferably at least one selected from the group consisting of a binder, a hot melt resin, and an adhesive. Preferable examples of the binder include a cellulose resin, an acrylic resin, and a combination thereof. Preferable examples of the heat fusion resin include a fluorine resin, a polyolefin resin, and any combination thereof. The hot-melt resin is preferably provided in the form of a heat-sealing film as will be described later. A preferable example of the adhesive is a thermosetting adhesive using a thermosetting resin such as an epoxy resin. Therefore, as disclosed in Patent Document 1, the organic polymer material is preferably at least one selected from the group consisting of a cellulose resin, an acrylic resin, a fluorine resin, a polyolefin resin, and an epoxy resin. I can say that.

The end insulating portion 18 is preferably formed by applying a liquid or slurry containing an organic polymer material (preferably a binder) and optionally a filler or the like. Preferable examples of the liquid or slurry application method include a dispensing method, a screen printing method, a spray method, a stamping method, and the like.

The positive electrode current collector all solid lithium battery 10 preferably further includes a positive electrode current collector 20 on the surface of the oriented positive electrode plate 12 opposite to the solid electrolyte layer 14. The positive electrode current collector 20 is a metal foil. The thickness of the metal foil is 5 to 30 μm, preferably 5 to 25 μm, more preferably 10 to 25 μm, and still more preferably 10 to 20 μm. By increasing the thickness as described above, a sufficient current collecting function can be ensured. Moreover, since it is rich in flexibility when it is a very thin metal foil as described above, it becomes easy to adhere to the entire surface of the oriented positive electrode plate 12 uniformly. The metal constituting the positive electrode current collector 20 is not particularly limited as long as it does not react with the aligned positive electrode plate 12, and may be an alloy. Preferred examples of such metals include stainless steel, aluminum, copper, platinum, and nickel, and more preferably stainless steel and nickel.

The positive electrode current collector 20 is preferably brought into full contact with the surface of the oriented positive electrode plate 12 opposite to the solid electrolyte layer 14 in a non-adhesive state containing no adhesive. By doing so, no interfacial stress is generated between the aligned positive electrode plate 12 and the positive electrode current collector 20, and therefore, deterioration factors such as interfacial delamination can be eliminated, and long-term reliability is improved. Can do. That is, interfacial peeling caused by expansion and contraction of the alignment positive electrode plate 12 due to charge and discharge and an increase in contact resistance caused thereby can be significantly suppressed, and long-term reliability can be improved.

It is preferable that the positive electrode current collector 20 also serves as a positive electrode exterior material that covers the outer side of the aligned positive electrode plate 12. For example, as shown in FIG. 1, two unit cells are stacked in parallel symmetrically via a single negative electrode current collector 24 to expose the positive electrode current collector 20 to the outside of the all-solid-state lithium battery 10. It is good also as a structure. When configured in such a parallel stacked battery, the negative electrode current collector 24 can function as a current collector common to two adjacent unit batteries.

The positive electrode current collector 20 is preferably pressed against the aligned positive electrode plate 12. Since the metal foil which is the positive electrode current collector 20 is a flexible thin conductive material, a large number of contact points between the positive electrode current collector 20 and the alignment positive electrode plate 12 can be secured by pressing, and the alignment positive electrode plate 12 can be secured. Can be more uniformly adhered to the entire surface. Thereby, even in the case of an adhesive-free non-adhesive state, a desirable current collecting effect can be obtained. The method of pressing is not particularly limited. For example, the pressing is performed from the outside of the positive electrode current collector 20 toward the alignment positive electrode plate 12 using a flexible pressing member (for example, foam metal) that does not damage the positive electrode current collector 20. A method, a method using a pressure difference between the inside and outside of the positive electrode current collector 20, or the like can be employed. In particular, it is preferable that the positive current collector 20 is pressed against the oriented positive electrode plate 12 due to a difference in internal and external pressures of the positive current collector 20. That is, it is only necessary that the orientation positive electrode plate 12 side of the positive electrode current collector 20 is depressurized or the side opposite to the orientation positive electrode plate 12 of the positive electrode current collector 20 is pressurized. In any case, since the metal foil as the positive electrode current collector 20 is a flexible thin conductive material according to the pressing using the internal and external pressure difference of the positive electrode current collector 20, the surface of the oriented positive electrode plate 12 Thus, the contact can be made at more contact points, and the current collecting effect can be further enhanced. The positive electrode current collector 20 and the aligned positive electrode plate 12 are in a non-adhered state. This means that the positive electrode current collector 20 and the aligned positive electrode plate 12 are partially (for example, part of the outer peripheral portion of the aligned positive electrode plate 12) and are adhesive resins. It is not excluded that it is fixed by, for example. Such a resin is used for the purpose of temporary adhesion to prevent misalignment of the oriented positive electrode plate when assembling the battery.

According to a particularly preferred embodiment of the present invention, the laminate including the oriented positive electrode plate 12, the solid electrolyte layer 14, the intermediate layer 15, and the negative electrode layer 16 (if present) is packaged or sealed with an exterior material. In this aspect, it is preferable that the positive electrode current collector 20 constitutes a part of the exterior material, and the accommodation space of the laminate that is packaged or sealed with the exterior material is decompressed. The storage space can be depressurized, for example, by packaging or sealing with an exterior material under reduced pressure, or by degassing the storage space after packaging or sealing the exterior material. As described above, since the metal foil that is the positive electrode current collector 20 is a flexible thin conductive material, the contact point of the positive electrode current collector 20 with the surface of the aligned positive electrode plate 12 is increased by reducing the storage space. Can be brought into close contact with. Moreover, if the packaging material is packaged or sealed in an airtight manner, it is possible to maintain a reduced pressure in the accommodation space of the laminate over a long period of time. Can be exerted over. The degree of vacuum may be set as appropriate based on the flexibility of the metal and the strength of the laminate.

A negative electrode current collector 24 is preferably provided outside the negative electrode current collector negative electrode layer 16 (outside of the intermediate layer 15 when there is no negative electrode layer 16). The negative electrode current collector 24 may also serve as a negative electrode exterior material that covers the outside of the negative electrode. For example, as shown in FIG. 4, contrary to the configuration shown in FIG. 1, two unit cells are stacked vertically and symmetrically via one positive current collector 20 to form a negative current collector 24. May be exposed to the outside of the all-solid-state lithium battery. When configured in such a parallel stacked battery, the positive electrode current collector 20 can function as a current collector common to two adjacent unit batteries.

The negative electrode current collector 24 may be made of the same or different material as the positive electrode current collector 20, but is preferably made of the same kind of material. The metal constituting the negative electrode current collector 24 is not particularly limited as long as it does not react with the negative electrode layer 16 and may be an alloy. Preferred examples of such a metal include stainless steel, aluminum, copper, platinum and nickel, and more preferred are stainless steel and nickel. The negative electrode current collector 24 is preferably a metal plate or a metal foil, and more preferably a metal foil. Therefore, it can be said that the most preferred current collector is a stainless steel foil or a nickel foil. The preferred thickness of the metal foil is 1 to 30 μm, more preferably 5 to 25 μm, and still more preferably 10 to 20 μm.

The all-solid-state lithium battery 10 in the end sealing portion includes an oriented positive electrode plate 12, a solid electrolyte layer 14, an intermediate layer 15, a negative electrode layer 16, and (not present) that are not covered with the positive electrode current collector 20 and the negative electrode current collector 24. In this case, it is preferable that an end sealing portion 26 made of a sealing material for sealing the exposed portion of the end insulating portion 18 is further provided. The end sealing part 26 is provided, and the orientation positive electrode plate 12, the solid electrolyte layer 14, the intermediate layer 15, the negative electrode layer 16, and the end insulating part 18 are not covered with the positive electrode current collector 20 and the negative electrode current collector 24. By sealing the exposed portion, it is possible to ensure excellent moisture resistance (desirably moisture resistance at high temperature). The end sealing portion 26 is made of a sealing material. The sealing material can seal the exposed portion not covered with the positive electrode current collector 20, the negative electrode current collector 24, and the end insulating portion 18 to ensure excellent moisture resistance (preferably moisture resistance at high temperature). If it is a thing, it will not specifically limit. However, it goes without saying that it is desirable that the sealing material ensure electrical insulation between the positive electrode current collector 20 and the negative electrode current collector 24. In that sense, the sealing material preferably has a 1 × 10 ⁶ Ωcm or more resistivity, more preferably 1 × 10 ⁷ Ωcm or more, still more preferably 1 × 10 ⁸ Ωcm or more. The sealing material is preferably a resin-based sealing material containing a resin, and the resin-based sealing material may be made of a mixture of a resin (preferably an insulating resin) and an inorganic material. Alternatively, the sealing material may be a glass-based sealing material containing glass. As these sealing agents, known ones as disclosed in Patent Document 1 can be used.

Battery thickness In the case of a configuration including one unit battery, the all-solid lithium battery preferably has a thickness of 60 to 5000 μm, more preferably 70 to 4000 μm, still more preferably 80 to 3000 μm, and particularly preferably. Is from 90 to 2000 μm, most preferably from 100 to 1000 μm. According to the present invention, the oriented positive electrode plate can be made relatively thick, while the current collector also serves as an exterior material, so that the thickness of the entire battery can be made relatively thin.

Method for Producing Lithium Cobalt Oxide Oriented Sintered Plate The oriented positive electrode plate or oriented sintered plate used in the all solid lithium battery of the present invention may be produced by any method, but preferably, as exemplified below (1) Production of LiCoO ₂ template particles, (2) Production of matrix particles, (3) Production of green sheets, and (4) Production of oriented sintered plates.

(1) Preparation of LiCoO ₂ template particles Co ₃ O ₄ raw material powder and Li ₂ CO ₃ raw material powder are mixed. The obtained mixed powder is fired at 500 to 900 ° C. for 1 to 20 hours to synthesize LiCoO ₂ powder. The obtained LiCoO ₂ powder is pulverized to a volume-based D50 particle size of 0.1 to 10 μm by a pot mill to obtain plate-like LiCoO ₂ particles capable of conducting lithium ions parallel to the plate surface. The obtained LiCoO ₂ particles are easily cleaved along the cleavage plane. It is to cleave by crushing the LiCoO ₂ particles to prepare a LiCoO ₂ template particles. Such LiCoO ₂ particles can be obtained by a method of crushing after growing a green sheet using LiCoO ₂ powder slurry, a plate method such as a flux method, hydrothermal synthesis, single crystal growth using a melt, or a sol-gel method. It can also be obtained by a method of synthesizing crystals.

In this step, the profile of the primary particles 11 constituting the oriented positive electrode plate 12 can be controlled as follows.
-By adjusting at least one of the aspect ratio and the particle size of the LiCoO ₂ template particles, the total area ratio of the low-angle primary particles having an orientation angle of more than 0 ° and not more than 30 ° can be controlled. Specifically, the larger the aspect ratio of LiCoO ₂ template particles, also, the larger the particle size of the LiCoO ₂ template particles, it is possible to increase the total area ratio of the low-angle primary particles. The aspect ratio and particle size of the LiCoO ₂ template particles are the particle size of the Co ₃ O ₄ raw material powder and the Li ₂ CO ₃ raw material powder, the pulverization conditions (pulverization time, pulverization energy, pulverization method, etc.), and pulverization, respectively. It can be controlled by adjusting at least one of the subsequent classifications.
-By adjusting the aspect ratio of the LiCoO ₂ template particles, the total area ratio of the primary particles 11 having an aspect ratio of 4 or more can be controlled. Specifically, the total area ratio of the primary particles 11 having an aspect ratio of 4 or more can be increased as the aspect ratio of the LiCoO ₂ template particles is increased. The method for adjusting the aspect ratio of the LiCoO ₂ template particles is as described above.
-The average particle size of the primary particles 11 can be controlled by adjusting the particle size of the LiCoO ₂ template particles.
-The density of the aligned positive electrode plate 12 can be controlled by adjusting the particle size of the LiCoO ₂ template particles. Specifically, the density of the aligned positive electrode plate 12 can be increased as the particle size of the LiCoO ₂ template particles is reduced.

(2) Production of matrix particles Co ₃ O ₄ raw material powder is used as matrix particles. The volume-based D50 particle size of the Co ₃ O ₄ raw material powder is not particularly limited and can be, for example, 0.1 to 1.0 μm, but is preferably smaller than the volume-based D50 particle size of LiCoO ₂ template particles. The matrix particles can also be obtained by subjecting a Co (OH) ₂ raw material to heat treatment at 500 to 800 ° C. for 1 to 10 hours. Further, the matrix particles, other _Co 3 _{O 4,} may be used Co _{(OH) 2} particles, may be used LiCoO ₂ particles.

In this step, the profile of the primary particles 11 constituting the oriented positive electrode plate 12 can be controlled as follows.
-Low angle primary whose orientation angle is greater than 0 ° and less than 30 ° by adjusting the ratio of the particle size of matrix particles to the particle size of LiCoO ₂ template particles (hereinafter referred to as “matrix / template particle size ratio”) The total area ratio of the particles can be controlled. Specifically, the smaller the matrix / template particle size ratio, that is, the smaller the particle size of the matrix particles, the easier it is for the matrix particles to be incorporated into the LiCoO ₂ template particles in the firing step described later. The total area ratio can be increased.
-The total area ratio of the primary particles 11 having an aspect ratio of 4 or more can be controlled by adjusting the matrix / template particle size ratio. Specifically, the smaller the matrix / template particle size ratio, that is, the smaller the particle size of the matrix particles, the higher the total area ratio of the primary particles 11 having an aspect ratio of 4 or more.
-The density of the aligned positive electrode plate 12 can be controlled by adjusting the matrix / template particle size ratio. Specifically, the smaller the matrix / template particle size ratio, that is, the smaller the particle size of the matrix particles, the higher the density of the aligned positive electrode plate 12 can be.

(3) Production of Green Sheet LiCoO ₂ template particles and matrix particles are mixed at 100: 3 to 3:97 to obtain a mixed powder. While mixing this mixed powder, dispersion medium, binder, plasticizer, and dispersant, the mixture is stirred under reduced pressure to defoam and adjusted to a desired viscosity to form a slurry. Next, a molded body is formed by molding the prepared slurry using a molding technique capable of applying a shearing force to LiCoO ₂ template particles. In this way, the average orientation angle of each primary particle 11 can be more than 0 ° and not more than 30 °. A doctor blade method is suitable as a forming technique capable of applying a shearing force to LiCoO ₂ template particles. When the doctor blade method is used, a green sheet as a molded body is formed by molding the prepared slurry on a PET film.

In this step, the profile of the primary particles 11 constituting the oriented positive electrode plate 12 can be controlled as follows.
-By adjusting the molding speed, the total area ratio of the low-angle primary particles whose orientation angle is more than 0 ° and not more than 30 ° can be controlled. Specifically, the higher the molding speed, the higher the total area ratio of the low-angle primary particles.
-The average particle diameter of the primary particles 11 can be controlled by adjusting the density of the compact. Specifically, the average particle diameter of the primary particles 11 can be increased as the density of the molded body is increased.
-The density of the aligned positive electrode plate 12 can also be controlled by adjusting the mixing ratio between the LiCoO ₂ template particles and the matrix particles. Specifically, the density of the aligned positive electrode plate 12 can be lowered as the number of LiCoO ₂ template particles is increased.

(4) Preparation of Oriented Sintered Plate A slurry compact is placed on a zirconia setter and heat-treated (primary firing) at 500 to 900 ° C. for 1 to 10 hours to obtain a sintered plate as an intermediate . This sintered plate is placed on a zirconia setter while being sandwiched between lithium sheets (for example, Li ₂ CO ₃ -containing sheets) and subjected to secondary firing to obtain a LiCoO ₂ sintered plate. Specifically, a setter on which a sintered plate sandwiched between lithium sheets is placed is placed in an alumina sheath and baked at 700 to 850 ° C. for 1 to 20 hours in the atmosphere. It is sandwiched between sheets and fired at 750 to 900 ° C. for 1 to 40 hours to obtain a LiCoO ₂ sintered plate. This firing step may be performed in two steps or may be performed once. When firing twice, it is preferable that the first firing temperature is lower than the second firing temperature. The total amount of lithium sheet used in the secondary firing may be such that the Li / Co ratio, which is the molar ratio of the amount of Li in the green sheet and the lithium sheet, to 1.0 with respect to the amount of Co in the green sheet. .

In this step, the profile of the primary particles 11 constituting the oriented positive electrode plate 12 can be controlled as follows.
-The total area ratio of the low-angle primary particles whose orientation angle is more than 0 ° and not more than 30 ° can be controlled by adjusting the heating rate during firing. Specifically, the higher the rate of temperature rise, the more the sintering of the matrix particles is suppressed, and the total area ratio of the low-angle primary particles can be increased.
-The total area ratio of low-angle primary particles whose orientation angle is more than 0 ° and not more than 30 ° can also be controlled by adjusting the heat treatment temperature of the intermediate. Specifically, the lower the heat treatment temperature of the intermediate, the more the sintering of the matrix particles is suppressed, and the total area ratio of the low-angle primary particles can be increased.
-The average particle diameter of the primary particles 11 can be controlled by adjusting at least one of the heating rate during firing and the heat treatment temperature of the intermediate. Specifically, the average particle diameter of the primary particles 11 can be increased as the rate of temperature increase is increased and the heat treatment temperature of the intermediate is decreased.
-Controlling the average particle diameter of the primary particles 11 also by adjusting at least one of the amount of Li (for example, Li ₂ CO ₃ ) and the amount of sintering aid (for example, boric acid or bismuth oxide) during firing. Can do. Specifically, the average particle diameter of the primary particles 11 can be increased as the amount of Li is increased and as the amount of the sintering aid is increased.
-The density of the alignment positive electrode plate 12 can be controlled by adjusting the profile during firing. Specifically, the density of the aligned positive electrode plate 12 can be increased as the firing temperature is lowered and the firing time is lengthened.

The present invention will be described more specifically with reference to the following examples.

Examples A1 to A8
(1) Preparation of oriented positive electrode plate (1a) Preparation of LCO template particles Co ₃ O ₄ raw material powder (volume basis D50 particle size 0.8 μm, manufactured by Shodo Chemical Co., Ltd.) and Li ₂ CO ₃ raw material powder (volume basis) D50 particle size 2.5 μm, manufactured by Honjo Chemical Co., Ltd.) was mixed and fired at 800 ° C. to 900 ° C. for 5 hours to synthesize LiCoO ₂ raw material powder. The obtained LiCoO ₂ powder was pulverized to obtain plate-like LiCoO ₂ particles (hereinafter referred to as LCO template particles). The volume-based D50 particle size of the LCO template particles was adjusted to 0.5 μm.

(1b) Production of Co ₃ O ₄ matrix particles Co ₃ O ₄ raw material powder (manufactured by Shodo Chemical Industry Co., Ltd.) was prepared as matrix particles. The volume-based D50 particle size of the matrix particles was 0.3 μm.

(1c) was mixed with LCO / _Co 3 _{O 4} produced LCO template particles of the green sheets and _Co 3 _{O 4} matrix grains. The weight ratio of LCO template particles to Co ₃ O ₄ matrix particles was 50:50. 100 parts by weight of the mixed powder, 100 parts by weight of a dispersion medium (toluene: isopropanol = 1: 1), 10 parts by weight of a binder (polyvinyl butyral: product number BM-2, manufactured by Sekisui Chemical Co., Ltd.), and a plasticizer (DOP : 4 parts by weight of Di (2-ethylhexyl) phthalate (manufactured by Kurokin Kasei Co., Ltd.) and 2 parts by weight of a dispersant (product name: Leodol SP-O30, manufactured by Kao Corporation) were mixed. The mixture was degassed by stirring under reduced pressure, and a slurry was prepared by adjusting the viscosity to 4000 cP. The viscosity was measured with an LVT viscometer manufactured by Brookfield. The prepared slurry was formed into a sheet shape on a PET film by a doctor blade method so that the thickness after drying was 48 μm at a forming speed of 100 m / h, and an LCO / Co ₃ O ₄ green sheet was formed. Obtained.

(1d) Preparation Li ₂ CO ₃ raw material powder of lithium sheet and (volume basis D50 particle size 2.5 [mu] m, Honjo Chemical Co., Ltd.) 100 parts by weight, a binder (polyvinyl butyral: No. BM-2, manufactured by Sekisui Chemical Co., Ltd. ) 5 parts by weight, 2 parts by weight of a plasticizer (DOP: di (2-ethylhexyl) phthalate, manufactured by Kurokin Kasei Co., Ltd.) and 2 parts by weight of a dispersant (product name: Leodol SP-O30, manufactured by Kao Corporation) And mixed. The resulting mixture was stirred and degassed under reduced pressure, and the viscosity was adjusted to 4000 cP to prepare a Li ₂ CO ₃ slurry. The viscosity was measured with an LVT viscometer manufactured by Brookfield. The prepared Li ₂ CO ₃ slurry was formed into a sheet on a PET film by a doctor blade method to form a Li ₂ CO ₃ green sheet (hereinafter referred to as a lithium sheet).

(1e) Preparation of oriented sintered plate The LCO / Co ₃ O ₄ green sheet peeled off from the PET film was placed on a zirconia setter and subjected to primary firing at 900 ° C. for 5 hours to obtain a sintered plate as an intermediate. Obtained. The sintered plate was placed on a zirconia setter with the lithium sheet sandwiched between the upper and lower sides, and subjected to secondary firing to obtain a LiCoO ₂ sintered plate. Specifically, a zirconia setter on which a sintered plate sandwiched between lithium sheets is placed is placed in a 90 mm square alumina sheath and held at 800 ° C. for 5 hours in the atmosphere. The sheet was sandwiched between upper and lower sheets and fired at 900 ° C. for 20 hours. Thus, a LiCoO ₂ sintered plate having a thickness of 40 μm was obtained as an oriented positive plate. The total amount of the lithium sheet in the secondary firing, to Co amount of LCO / _Co 3 _{O 4} in the green sheet, the molar ratio of LCO / _Co 3 _{O 4} green sheet and Li of the lithium in the sheet Li / The amount was set such that the Co ratio was 1.05.

(2) Production of Solid Electrolyte Layer A lithium phosphate sintered body target having a length of 5 inches (about 12.7 cm) × width of 15 inches (about 38.1 cm) was prepared, and a sputtering apparatus (ILC- manufactured by Canon Anelva Co., Ltd.) was prepared. 702), an RF magnetron method was used to perform sputtering so that the gas type N ₂ was 0.4 Pa, the output was 1.2 kW, and the film thickness was 3 μm. Thus, a LiPON-based solid electrolyte layer having a thickness of 3 μm was formed on the oriented positive electrode plate.

(3) Insulation treatment of battery edge part In order to ensure the insulation of the battery edge part, the area | region of the width | variety 250 +/- 100micrometer along the outer periphery of the LiPON type solid electrolyte layer was covered with the polyimide resin.

(4) Production of Intermediate Layer An intermediate layer having the composition and thickness shown in Table 1 was formed on the LiPON solid electrolyte layer as follows.

In the case of the Au intermediate layer (Example A1), an Au film having a thickness of 20 nm was formed on the solid electrolyte layer by sputtering using an ion sputtering apparatus (manufactured by JEOL Ltd., JFC-1500). At this time, the size of the intermediate layer was set to 10 mm square using a mask so that the intermediate layer could be accommodated in the positive electrode region of 10.5 mm square.

In the case of Sn intermediate layers (examples A2 to A4), Si intermediate layers (example A5), Bi intermediate layers (example A6) and Al intermediate layers (examples A7 and A8), a Sn target having a diameter of 4 inches (about 10 cm), A Si target, Bi target, or Al target is prepared, and is shown in Table 1 with a sputtering apparatus (SPF-210HS, manufactured by Canon Anelva Co., Ltd.) using an RF magnetron method with an Ar gas of 1 Pa and an output of 0.1 kW. Sputtering was performed to obtain a film thickness. Thus, an intermediate layer having the composition and thickness shown in Table 1 was formed on the solid electrolyte layer. At this time, the size of the intermediate layer was set to 10 mm square using a mask so that the intermediate layer could be accommodated in the positive electrode region of 10.5 mm square.

(5) Production of negative electrode layer In Examples A1 to A7, a negative electrode layer was formed on the intermediate layer as follows. First, a tungsten boat carrying lithium metal was prepared. A Li thin film was formed on the surface of the intermediate layer by vapor deposition using a vacuum vapor deposition apparatus (Sanyu Electronics Co., Ltd., carbon coater SVC-700) while vaporizing Li by resistance heating. At this time, using a mask, the size of the negative electrode layer was set to 10 mm square so that the negative electrode layer was within the 10.5 mm square positive electrode region. In this way, a unit cell was produced in which a Li-deposited film having a thickness of 10 μm was formed as a negative electrode layer on the solid electrolyte layer.

In Example A8, the negative electrode layer was not formed in order to use Li precipitated during charging as the negative electrode active material. Thus, a unit cell having no negative electrode layer on the solid electrolyte layer was produced.

(6) Battery assembly A laminated sheet obtained by laminating a 20 μm thick Ni foil and a 15 μm thick nylon resin was cut into a 13 mm square to form a current collector plate. Adhere 0.9mm wide frame-shaped polychlorotrifluoroethylene resin (thickness 50μm) with 12.8mm square outer edge shape and 11mm square hole punched inside it to the Ni foil side of the current collector plate Thus, an end sealing portion was formed. The composite member thus obtained was placed with the Ni foil side of the current collector plate facing up, and the unit cell obtained in (5) above was placed in the region surrounded by the end sealing portion with the negative electrode facing down. Placed. On the positive electrode of the placed unit cell, the current collector was placed with the Ni foil side down, and using a pulse heat type heating device (manufactured by Nippon Avionics Co., Ltd., HT-13X13 (40) NTN), Under reduced pressure, the end sealing part was heated at 420 ° C. while applying a load of 3 kg. In this way, the end sealing portion and the two upper and lower current collecting plates were bonded and sealed so as to cover the entire outer periphery of the unit cell, thereby obtaining an all solid lithium battery in a sealed form.

(7) Various evaluation The following evaluation was performed about the obtained all-solid-state lithium battery. The results were as shown in Table 1.

(Average orientation angle)
An EBSD image in a cross section perpendicular to the plate surface of the positive electrode was obtained using a scanning electron microscope (manufactured by JEOL Ltd., model JSM-7800M) with a backscattered electron diffraction image system. The average orientation angle of primary particles was measured by the following procedure. First, in an EBSD image obtained by observing a rectangular area of 95 μm × 125 μm at a magnification of 1000 times, three horizontal lines that divide the positive electrode into four equal parts in the thickness direction and three vertical lines that divide the positive electrode into four equal parts in the plate surface direction And subtracted. Next, the average orientation angle of the primary particles was obtained by arithmetically averaging the orientation angles of all the primary particles intersecting at least one of the three horizontal lines and the three vertical lines.

(Cycle capacity maintenance rate)
The lithium ion battery was charged with a constant current of 0.2 mA to a charging voltage value of 4.0 V, and then charged with a constant voltage of 4.0 V until the current reached 0.04 mA. Then, discharged at a constant current of 0.2mA up to the cut-off voltage value 3.0 V, the discharge capacity was measured _{W 0.} This measurement was repeated 50 times, and the 50th discharge capacity W ₅₀ was measured. The W ₅₀ and the value obtained by multiplying 100 by dividing by _{W 0} and evaluated as the cycle capacity retention rate (%).

Example A9 (comparison)
A battery was fabricated and evaluated in the same manner as in Example A1 except that no intermediate layer was formed. The results were as shown in Table 1.

Example A10 (comparison)
A battery was fabricated and evaluated in the same manner as in Example A1, except that a Cu intermediate layer having a thickness of 20 nm was formed instead of the Au intermediate layer. The Cu intermediate layer is formed by preparing a Cu target having a diameter of 4 inches (about 10 cm), and using a sputtering apparatus (SPF-430H, manufactured by Canon Anelva Co., Ltd.) with a DC magnetron method, the gas species Ar is 0.3 Pa, The sputtering was performed at a current of 0.5 A so that the film thickness was 20 nm. The results were as shown in Table 1.

Example A11 (comparison)
A battery was produced and evaluated in the same manner as in Example A2, except that the oriented positive electrode plate was produced as follows. The results were as shown in Table 1.

(Preparation of oriented positive electrode plate)
Co ₃ O ₄ raw material powder (volume basis D50 particle size 0.3 [mu] m, Seido Chemical Industry Co., Ltd.) _Bi 2 _{O 3} at a ratio of 5 wt% (the volume basis D50 particle size 0.3 [mu] m, the solar mineral Engineering Co., Ltd. ) Was added to obtain a mixed powder. 100 parts by weight of the mixed powder, 100 parts by weight of a dispersion medium (toluene: isopropanol = 1: 1), 10 parts by weight of a binder (polyvinyl butyral: product number BM-2, manufactured by Sekisui Chemical Co., Ltd.), and a plasticizer (DOP : 4 parts by weight of di (2-ethylhexyl) phthalate (manufactured by Kurokin Kasei Co., Ltd.) and 2 parts by weight of a dispersant (product name: Leodol SP-O30, Kao Corporation) were mixed. The mixture was defoamed by stirring under reduced pressure and adjusted to a viscosity of 4000 cP. The viscosity was measured with an LVT viscometer manufactured by Brookfield. The slurry prepared as described above was formed into a sheet shape on a PET (polyethylene terephthalate) film so that the thickness after drying was 45 μm by a doctor blade method to produce a green sheet. The green sheet peeled off from the PET film was cut out, placed on the center of a zirconia setter (dimension 90 mm square, height 1 mm) with a protrusion height of 300 μm, and fired at 1300 ° C. for 5 hours The temperature was lowered at a temperature drop rate of 50 ° C./h. The portion not welded to the setter was taken out as a Co ₃ O ₄ oriented fired plate. Co ₃ O ₄ placing the _Li 2 CO ₃ sheets so that Li / Co = 1.3 to orientation firing plate, a _Co 3 _{O 4} oriented sintered plate by 10 hours of heat treatment at 840 ° C. in air Lithium was introduced. Thus, a LiCoO ₂ oriented sintered plate having a thickness of 40 μm was obtained as an oriented positive plate.

Examples B1 to B8
(1) orientation positive electrode plate prepared in (1a) Preparation of LCO template grains Co ₃ O ₄ raw material powder (volume basis D50 particle size 0.8 [mu] m, Seido Chemical Industry Co., Ltd.) and _Li 2 CO ₃ raw material powder (by volume D50 particle size 2.5 μm, manufactured by Honjo Chemical Co., Ltd.) was mixed and baked at 800 ° C. for 5 hours to synthesize LiCoO ₂ raw material powder. At this time, by adjusting the firing temperature and firing time, the volume was adjusted reference D50 particle size of the LiCoO ₂ material powder to values shown in Table 2. The obtained LiCoO ₂ powder was pulverized to obtain plate-like LiCoO ₂ particles (LCO template particles). In Examples B1, B2 and B4 to B8, a pot mill was used, and in Example B3, a wet jet mill was used. At this time, the volume-based D50 particle size of the LCO template particles was adjusted to the value shown in Table 2 by adjusting the pulverization time. Further, the aspect ratio of the LiCoO ₂ template particles was as shown in Table 2. The aspect ratio of LiCoO ₂ template particles was measured by SEM observation of the obtained template particles.

(1b) Production of Co ₃ O ₄ matrix particles Co ₃ O ₄ raw material powder (manufactured by Shodo Chemical Industry Co., Ltd.) was prepared as matrix particles. The volume-based D50 particle size of the matrix particles was as shown in Table 2. However, Example B4 did not use matrix particles.

(1c) Production of LCO / Co ₃ O ₄ Green Sheet LCO template particles and Co ₃ O ₄ matrix particles were mixed. The weight ratio of LCO template grains and _Co 3 _{O 4} matrix particles were as shown in Table 2. However, in Example B4, since the matrix particles were not used, the weight ratio was 100: 0. 100 parts by weight of the mixed powder, 100 parts by weight of a dispersion medium (toluene: isopropanol = 1: 1), 10 parts by weight of a binder (polyvinyl butyral: product number BM-2, manufactured by Sekisui Chemical Co., Ltd.), and a plasticizer (DOP : 4 parts by weight of Di (2-ethylhexyl) phthalate (manufactured by Kurokin Kasei Co., Ltd.) and 2 parts by weight of a dispersant (product name: Leodol SP-O30, manufactured by Kao Corporation) were mixed. The mixture was degassed by stirring under reduced pressure, and a slurry was prepared by adjusting the viscosity to 4000 cP. The viscosity was measured with an LVT viscometer manufactured by Brookfield. The prepared slurry was formed into a sheet on a PET film by a doctor blade method so that the thickness after drying was 40 μm at a forming speed of 100 m / h to obtain a green sheet.

(1d) Preparation of oriented sintered plate The green sheet peeled off from the PET film was placed on a zirconia setter and subjected to primary firing at 900 ° C. for 5 hours (Examples B1 to B6 and B8) or 800 ° C. for 5 hours (Example B7). As a result, a sintered plate as an intermediate was obtained. The sintered plate was placed on a zirconia setter while being sandwiched between lithium sheets, and then subjected to secondary firing to obtain a LiCoO ₂ sintered plate. Specifically, a zirconia setter on which a sintered plate sandwiched between lithium sheets is placed is placed in a 90 mm square alumina sheath and held at 800 ° C. for 5 hours in the atmosphere. The sheet was sandwiched between upper and lower sheets and fired at 900 ° C. for 20 hours. The total amount of the lithium sheet in the secondary firing, to Co amount of LCO / _Co 3 _{O 4} in the green sheet, the molar ratio of LCO / _Co 3 _{O 4} green sheet and Li of the lithium in the sheet Li / The amount was set so that the Co ratio would be the value shown in Table 2.

(2) Preparation of solid electrolyte layer A lithium phosphate sintered compact target having a diameter of 4 inches (about 10 cm) is prepared, and a gas type is generated by a RF magnetron method using a sputtering apparatus (SPF-430H, manufactured by Canon Anelva Co., Ltd.). Sputtering was performed so that the film thickness was 2 μm with N ₂ of 0.2 Pa and an output of 0.2 kW. Thus, a LiPON solid electrolyte sputtered film having a thickness of 2 μm was formed on the LiCoO ₂ sintered plate.

(3) Production of Intermediate Layer An Au film having a thickness of 500 mm was formed as an intermediate layer on the solid electrolyte layer by sputtering using an ion sputtering apparatus (JFC-1500, manufactured by JEOL Ltd.).

(4) Production of negative electrode layer A tungsten boat on which lithium metal was placed was prepared. Using a vacuum deposition apparatus (carbon coater SVC-700, manufactured by Sanyu Denshi Co., Ltd.), vapor deposition was performed by evaporating Li by resistance heating to form a thin film on the surface of the intermediate layer. At this time, using a mask, the size of the negative electrode layer was set to 9.5 mm square so that the negative electrode layer was within the 10 mm square positive electrode region. In this way, a unit cell was produced in which a Li-deposited film having a thickness of 10 μm was formed as a negative electrode layer on the solid electrolyte layer.

(5) Battery assembly A stainless foil with a thickness of 20 μm was cut into a 13 mm square to form a positive electrode current collector plate. Also, a 1 mm wide frame-shaped modified polypropylene resin film (thickness: 100 μm) having an outer edge shape of 13 mm square and an 11 mm square hole punched inside thereof was prepared. This frame-shaped resin film was laminated on the outer peripheral portion on the positive electrode current collector plate, and heat-pressed to form an end sealing portion. The unit cell was placed in a region surrounded by the end sealing portion on the positive electrode current collector plate. Similarly to the above, a stainless steel foil having a thickness of 20 μm was placed on the negative electrode side of the placed unit cell, and heated at 200 ° C. under reduced pressure while applying a load to the end sealing portion. Thus, the end sealing part and the upper and lower two stainless steel foils were bonded together over the entire outer periphery to seal the unit cell. Thus, an all solid lithium battery in a sealed form was obtained.

(6) Various evaluations The following evaluation was performed about the obtained all-solid-state lithium battery. The results were as shown in Table 3.
(Observation of primary particles constituting the positive electrode)
Using a scanning electron microscope with a backscattered electron diffraction image system (manufactured by JEOL Ltd., model JSM-7800M), obtain an EBSD image in a cross section perpendicular to the plate surface of the positive electrode, and calculate various parameters as follows. went.
-The average orientation angle of primary particles was calculated by arithmetically averaging the orientation angles of 30 primary particles arbitrarily selected on the EBSD image.
-In the EBSD image, the ratio (%) of the total area of primary particles having an orientation angle of more than 0 ° and 30 ° or less to the total area of 30 primary particles used for calculating the average orientation angle was calculated.
-In the EBSD image, the average particle diameter of 30 primary particles used for calculating the average orientation angle was calculated. Specifically, the arithmetic average value of the equivalent circle diameter of each of the 30 primary particles was defined as the average particle size of the primary particles.
-In the EBSD image, the average aspect ratio of 30 primary particles used to calculate the average orientation angle was calculated. Specifically, the arithmetic average value of the value obtained by dividing the maximum ferret diameter of each of the 30 primary particles by the minimum ferret diameter was taken as the average aspect ratio of the primary particles.
-In the EBSD image, the area ratio of primary particles having an aspect ratio of 4 or more was calculated among the 30 primary particles used for calculating the average orientation angle.

(Density of oriented positive electrode plate)
A 1000-magnification SEM image in the cross section of the orientation positive electrode plate polished by CP (cross section polisher) was binarized. Then, on the binarized image, the area ratio of the solid phase to the total area of the solid phase and the gas phase was calculated as the density.

(Rate performance)
The lithium ion battery was charged to 4.2 V with a constant current of 0.1 mA, and then charged with a constant voltage until the current reached 0.05 mA. Then, discharged at a constant current of 0.2mA up to 3.0 V, the discharge capacity was measured _{W 0.} In addition, after charging to 4.2 V with a constant current of 0.1 mA, charging is performed with a constant voltage until the current becomes 0.05 mA, and then discharging to 3.0 V with a constant current of 2.0 mA, and the discharge capacity W ₁ Was measured. The W ₁ was to evaluate the rate performance by multiplying by 100 divided by _{W 0.}

(Cycle capacity maintenance rate)
The lithium ion battery was charged to 4.2 V with a constant current of 0.1 mA, and then charged with a constant voltage until the current reached 0.05 mA. Then, discharge at 0.2mA constant current to 3.0 V, the discharge capacity was measured _{W 0.} This measurement was repeated 30 times, and the 30th discharge capacity W30 was measured. The W ₃₀ was to evaluate the cycle capacity retention rate by multiplying by 100 divided by _{W 0.}

Example B9 (comparison)
Batteries were prepared and evaluated in the same manner as in Examples B1 to B8, except that the LiCoO ₂ powder was used as it was as the LCO template particles without being pulverized. The results were as shown in Table 3.

Example B10 (comparison)
Batteries were prepared and evaluated in the same manner as in Examples B1 to B8, except that the volume-based D50 particle size of the Co ₃ O ₄ matrix particles was larger than those in Examples B1 to B8. The volume-based D50 particle size of the matrix particles of this example was 3.0 μm, and the particle size ratio of the LCO template particles to the Co ₃ O ₄ matrix particles was 0.2. The results were as shown in Table 3.

Example B11 (comparison)
Batteries were produced and evaluated in the same manner as in Examples B1 to B8, except that the green sheets were produced with a slurry using only Co ₃ O ₄ matrix particles without using LCO template particles. The results were as shown in Table 3.

Example B12 (comparison)
Batteries were produced and evaluated in the same manner as in Examples B1 to B8 except that the firing temperature for primary firing was 1200 ° C. The results were as shown in Table 3.

Example B13 (comparison)
A battery was produced and evaluated in the same manner as in Example B1, except that the positive electrode plate was produced as follows. The results were as shown in Table 3.

(Preparation of positive electrode plate)
The slurry prepared in Example B1 was dried as it was without being formed into a sheet. The dried product was fired in the same manner as in Example B1, and then polished to a thickness of 40 μm using a # 1200 SiC abrasive paper to obtain a positive electrode plate.

 

Claims (14)

1. An alignment positive electrode plate having a thickness of 30 μm or more formed of an oriented sintered body, wherein the oriented sintered body includes a plurality of primary particles formed of a lithium composite oxide having a layered rock salt structure, An oriented positive electrode plate in which the particles are oriented at an average orientation angle of more than 0 ° and not more than 30 ° with respect to the plate surface of the oriented positive electrode plate;
   A solid electrolyte layer provided on the oriented positive electrode plate and made of a lithium ion conductive material;
   An intermediate layer provided on the solid electrolyte layer and containing a metal that can be alloyed with lithium and having a thickness of 0.001 to 1 μm;
   An all-solid-state lithium battery.
2. The all-solid-state lithium battery according to claim 1, further comprising a negative electrode layer containing lithium on the intermediate layer.
3. The metal that can be alloyed with lithium is Al (aluminum), Si (silicon), Zn (zinc), Ga (gallium), Ge (germanium), Ag (silver), Au (gold), Pt (platinum), 3. The method according to claim 1, comprising at least one selected from the group consisting of Cd (cadmium), In (indium), Sn (tin), Sb (antimony), Pb (lead), and Bi (bismuth). All solid lithium battery.
4. The metal that can be alloyed with lithium includes at least one selected from the group consisting of Au (gold), Si (silicon), Sn (tin), Al (aluminum), and Bi (bismuth). 4. The all solid lithium battery according to any one of 1 to 3.
5. The all-solid-state lithium battery according to any one of claims 1 to 4, wherein the orientation positive electrode plate has a thickness of 30 to 100 µm.
6. The all-solid-state lithium battery according to any one of claims 1 to 5, wherein the lithium composite oxide is lithium cobalt oxide.
7. When the cross section of the oriented sintered body is analyzed by electron beam backscatter diffraction (EBSD), the orientation angle with respect to the plate surface of the oriented positive electrode plate of the primary particles included in the analyzed cross section is 0 °. The all-solid-state lithium battery according to any one of claims 1 to 6, wherein a total area of primary particles that are super 30 ° or less is 70% or more with respect to a total area of primary particles included in the cross section.
8. When the cross section of the oriented sintered body is analyzed by electron beam backscatter diffraction (EBSD), the total area of primary particles having an aspect ratio of 4 or more among the primary particles included in the analyzed cross section is obtained. The all-solid-state lithium battery according to any one of claims 1 to 7, which is 70% or more based on a total area of primary particles included in the cross section.
9. The all-solid-state lithium battery according to any one of claims 1 to 8, wherein an average particle diameter of the plurality of primary particles is 5 μm or more.
10. The all-solid-state lithium battery according to any one of claims 1 to 9, wherein a density of the oriented sintered body is 90% or more.
11. The all electrode according to any one of claims 1 to 10, further comprising a positive electrode current collector that is a metal foil having a thickness of 5 袖 m or more and 30 袖 m or less on a surface opposite to the solid electrolyte layer of the oriented positive electrode plate. Solid lithium battery.
12. The oriented positive electrode plate, the solid electrolyte layer and, if present, the laminate including the negative electrode layer is packaged or sealed with an exterior material, and the positive current collector constitutes a part of the exterior material, The all-solid-state lithium battery of Claim 11 with which the accommodation space of the said laminated body packaged or sealed with the said exterior material is pressure-reduced.
13. The lithium ion conductive material constituting the solid electrolyte layer is a garnet-based ceramic material, a nitride-based ceramic material, a perovskite-based ceramic material, a phosphate-based ceramic material, a sulfide-based ceramic material, a lithium-chloride-based material, or The all-solid-state lithium battery according to any one of claims 1 to 12, which is made of a polymer material.
14. The lithium ion conductive material constituting the solid electrolyte layer is composed of a Li-La-Zr-O based ceramic material and / or a lithium phosphate oxynitride (LiPON) based ceramic material. The all-solid-state lithium battery as described in any one.
    
    

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