JP2012256486A - Solid battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solid battery capable of realizing high capacity without needing a complicate manufacturing process.SOLUTION: The solid battery is arranged so that a fibrous electrode material has a surface which contains an active material of either positive or negative electrode on a circumference thereof, solid electrolyte layers are stacked on the circumference of the surface containing the active material except an edge part of the electrode material, and a compresses powder electrode material layer different from the electrode having the active material is filled in and stacked on a gap part formed by the solid electrolyte layers adjacent to each other and the solid electrolyte layer.

Description

  The present invention relates to a novel solid state battery, and more particularly to a solid state battery capable of increasing the capacity by having a specific structure.

In recent years, lithium batteries have been put into practical use as batteries having high voltage and high energy density. Due to the expansion of the use of lithium batteries in a wide range of fields and the demand for high performance, various studies have been conducted to further improve the performance of lithium batteries.
Among them, the use of non-flammable electrolytes compared to the conventional non-aqueous electrolyte type lithium batteries eliminates the need for flammable electrolytes, so the safety is high, the degree of freedom of the cell shape is high, the degree of freedom of the structure is increased, and the number of auxiliary devices Therefore, it is expected that the solid state battery will be put to practical use.

However, in order to realize the practical application of solid state batteries, various improvements such as the creation of a solid electrolyte capable of providing high capacity and high output and / or the creation of electrodes capable of realizing high electrode utilization efficiency are required. is there.
As one of the technologies capable of realizing the high capacity and high output of this solid battery, an attempt has been made to make the electrolyte layer as thin as possible with respect to the structure of the battery. Thinning has not been done. In addition, attempts have been made to reduce the maximum distance between the positive electrode mixture and the negative electrode mixture by thinning the positive electrode mixture and the negative electrode mixture (thin film battery), but the output is improved but the energy density is greatly increased. In both cases, satisfactory results have not been obtained.
This need for high capacity and high output is a common issue not only for solid state batteries but also for secondary batteries that use electrolyte, and attempts have been made to increase the capacity and output of batteries by changing the structure of the battery. Yes.

  For example, in Patent Document 1, a battery active material layer is formed on the surface of a fibrous material having electron conductivity, and the active material layer is further coated with a material having no electron conductivity and ion conductivity. Formed, and a metal material layer having electron conductivity is formed thereon, and a unit cell is formed by extracting terminals from the metal fiber in the center and the metal material layer on the outer periphery, and the unit cell is bundled A battery capable of being charged and discharged is described, which is arranged in a fabric or is made into a woven shape and is attached with a positive electrode terminal and a negative electrode terminal. As a specific example, a battery in which the positive electrode is nickel fiber, the metal material layer of the negative electrode is connected to the battery case, and the battery case is the negative electrode terminal is shown.

JP 2010-073533 A

However, in the battery described in the publication, it is necessary to form the metal material layer uniformly on the active material layer when forming the metal fiber in the center and the metal material layer in the outer periphery. No specific technique for coating to a uniform thickness is shown.
Therefore, an object of the present invention is to provide a solid state battery that does not require the complicated manufacturing process described above, and can arrange the positive electrode material and the negative electrode material at high density at close intervals, and can increase the capacity. That is.

As a result of intensive studies to achieve the above object, the present inventors have created an ion path by uniformly dispersing the active material and the electrolyte by the liquid phase and solid phase methods and maximizing the contact area. In addition, it has been found that it is extremely difficult for a conventionally known solid state battery to make a structure in which all active materials or conductors are in reliable contact with each other to form an electron path. completed.
The present invention has a surface containing a positive or negative electrode active material around a woven fibrous electrode material, and the periphery of the surface containing the active material except for an end of the electrode material The present invention relates to a solid battery in which a solid electrolyte layer is laminated, and a space formed by adjacent solid electrolyte layers and a powdered electrode material layer having a polarity different from that of the active material are filled and laminated on the solid electrolyte layer .

  According to the present invention, it is possible to obtain a solid battery capable of increasing the capacity without requiring a process that involves difficulty in manufacturing.

FIG. 1 is a schematic view showing a plane and a partial cross section of the solid state battery of the first embodiment of the present invention. FIG. 2A is a schematic diagram of a process product showing a process (1) in the process of manufacturing the solid state battery of the first embodiment of the present invention. FIG. 2B is a schematic diagram of a partial cross section of a process product showing a process (2) in the process of manufacturing the solid state battery of the first embodiment of the present invention. FIG. 2C is a schematic diagram of a plane, a front cross-section, and a partially enlarged cross-section of a process product showing a process (3) in the process of manufacturing the solid state battery of the first embodiment of the present invention. FIG. 2D is a schematic diagram of a plan and partial cross section of a process product showing a process (4) in the process of manufacturing the solid state battery of the first embodiment of the present invention. FIG. 2E is a schematic plan view and a partial cross-sectional view of a process product showing a process (5) in the process of manufacturing the solid state battery of the first embodiment of the present invention. FIG. 3 is a schematic view showing a plane and a partial cross section of the solid state battery according to the second embodiment of the present invention. FIG. 4 is a plan view and a cross section showing a state of a stacked solid battery in which one solid battery according to the first embodiment of the present invention is stacked and a positive electrode current collector and a negative electrode current collector are attached to both ends. FIG. FIG. 5 is a schematic view showing a conventional general lithium ion battery. FIG. 6 is a schematic view showing a conventional thin film battery. FIG. 7 is a schematic diagram of a solid state battery using a known three-dimensional electrode. FIG. 8 is a schematic diagram showing the dimensions of the solid state battery of the second embodiment of the present invention used in a simulation for comparing the solid state battery of the present invention with a conventional flat plate small battery. FIG. 9 is a table showing comparison results by simulation of the area, volume, and thickness of the solid state battery of the second embodiment of the present invention and the conventional flat small battery. FIG. 10 is a schematic diagram for explaining the dimensions of each member of the solid state battery according to the second embodiment of the present invention. FIG. 11 is a schematic diagram showing the relationship of each member in the solid state battery for studying the electronic conductivity and ion conductivity of the solid state battery of the second embodiment of the present invention. FIG. 12 is a schematic diagram showing the relationship of each member in a flat small battery for studying the electronic conductivity and ion conductivity of a conventional flat small battery. FIG. 13 is a schematic diagram showing dimensions of a solid state battery used for simulation in order to compare the solid state battery of the second embodiment of the present invention with a conventional flat small battery. FIG. 14 is a schematic diagram showing dimensions of a solid state battery used for simulation in order to compare the solid state battery of the second embodiment of the present invention with a conventional flat plate small battery.

In particular, in the present invention, the following embodiments can be mentioned.
1) The solid battery in which the woven fibrous electrode material is made of carbon containing a negative electrode active material, and the dusty electrode material is a dusty cathode material layer.
2) A positive electrode active material layer is laminated around a fibrous conductor in which the woven fibrous electrode material is woven, and the dusty electrode material is a dusty negative electrode material. The solid state battery.
3) The solid battery, wherein the woven fibrous conductor is a carbon or aluminum fiber around which a positive electrode active material layer is laminated.
4) The said solid battery by which a collector layer is laminated | stacked on the single side | surface of the said powder-like electrode material layer.
5) The solid battery, wherein the woven fibrous electrode material is a sheet obtained by pressing and flattening a woven fabric made of an electrode material.
6) The said solid battery which has the space | gap part in which the cross section parallel to the surface woven by the said woven fibrous electrode material as a warp and a weft is a square shape.
7) The end portion of the woven fibrous electrode material and the end portion of the current collector layer laminated on at least one surface of the dusty electrode material layer are connected to the respective current collectors. Solid battery.

  According to the solid battery of the present invention, the active material has a surface containing a positive or negative electrode active material around a woven fibrous electrode material, except for an end of the electrode material. A solid electrolyte layer is laminated around the surface including the solid electrolyte layer, and a gap formed by the solid electrolyte layers adjacent to each other and a powdered electrode material layer of an electrode different from the active material are filled and laminated on the solid electrolyte layer As a result, it is possible to increase the capacity without requiring a process with difficulty in manufacturing.

Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS.
A solid battery 1 according to a first embodiment of the present invention has a surface 3 containing a negative electrode active material around a woven fibrous negative electrode material 2, as shown in FIGS. A solid electrolyte layer 6 is laminated around the surface 3 containing the negative electrode active material except for the end portion 5 of the material 2, and pressure is applied to the void 7 formed by the solid electrolyte layers 6 adjacent to each other and the solid electrolyte layer. The powdered positive electrode material layer 8 is filled and laminated, and the positive electrode current collector layer 11 is laminated on at least one surface of the powdery positive electrode material layer 8, and the end portion 5 of the woven negative electrode material and the positive electrode current collector A negative electrode current collector 13 and a positive electrode current collector 14 are connected to the layer 11, respectively. As shown in FIG. 1, the positive electrode current collector layer 11 may be formed on the powdery positive electrode material layer and including an end portion for current collection.
As the woven fibrous negative electrode material in the first embodiment, the negative electrode active material is made of carbon, the negative electrode active material is made of a mixture of carbon and a solid electrolyte, or the woven fibrous negative electrode material. It can have a negative electrode active material layer around the conductor, and the surface of the woven fibrous negative electrode material has a surface containing the negative electrode active material.
In FIG. 1, the negative electrode current collector 13 and the positive electrode current collector 14 are installed from one side, but may be installed as a pair from each of the two sides.

Further, as shown in FIG. 3, the solid battery 1 according to the second embodiment of the present invention has a positive electrode active material surface 4 in which a positive electrode active material layer 4 ′ is laminated around a woven fibrous conductor. The solid electrolyte layer 6 is laminated around the surface 4 containing the positive electrode active material except for the end portion 5 of the positive electrode active material layer, and the void 7 and the solid formed by the solid electrolyte layers 6 adjacent to each other. A powdered negative electrode material layer 9 is filled and laminated on the electrolyte layer, and a negative electrode current collector layer 12 is laminated on at least one surface of the powdery negative electrode material layer 9, and the end portion 5 of the woven conductor is formed. The positive electrode current collector 14 and the negative electrode current collector 13 are connected to the negative electrode current collector layer 12. The negative electrode current collector layer 12 may be formed on the powdery positive electrode material layer and including an end portion for current collection.
In the second embodiment of the present invention, the woven fibrous positive electrode material is a woven fibrous material made of a conductor, such as carbon or aluminum fiber, for example, a positive electrode active material layer around a woven fabric. 4 'is laminated | stacked and it has the surface 4 containing a positive electrode active material on the surface.
In FIG. 3, the positive electrode current collector 14 and the negative electrode current collector 13 are each installed from one side, but may be installed as a pair from each of the two sides.

  The solid battery according to the embodiment of the present invention has the above-described configuration, so that 1) the distance between the positive electrode and the negative electrode can be made as small as possible, and 2) the amount of the positive electrode and the negative electrode can be the same as those of conventional batteries. Therefore, the volume of the positive and negative electrodes can be set to the same level, and the volume can be almost the same. 3) The maximum distance between the positive and negative electrodes can be reduced, and the output density can be increased. 4) A solid electrolyte with low Li ion conductivity can be used, 5) thin film coating can be performed using a solid material as the electrolyte, 6) current collection from both electrodes is easy, and 7) electronic conductivity and ionic conductivity of the electrode. Can be kept sufficiently, and 8) can satisfy the 8 requirements of not requiring difficult steps in manufacturing.

The solid state battery according to the first embodiment of the present invention may be, for example, a sheet made by pressing and planarizing a carbon fiber woven fabric containing the negative electrode active material shown in FIG. Step (1) of preparing a material, step (2) of laminating a solid electrolyte layer from both sides of the sheet shown in FIG. 2B, coating a positive electrode material from both sides of the sheet shown in FIG. A step (3) of filling and laminating a dusty positive electrode material layer on the voids and solid electrolyte layers formed by the adjacent solid electrolyte layers, and collecting the positive electrode on at least one side of the dusty positive electrode material layer shown in FIG. 2D It can be obtained by a method including the step (4) of laminating electric bodies.
In the solid battery of the embodiment of the present invention, following the step (4) shown in FIG. 2D, the end of the woven negative electrode material and the positive electrode current collector shown in FIG. A step (5) of attaching the current collectors 14 may be included.
Further, as shown in FIG. 4, the solid state battery according to the embodiment of the present invention is a stacked type in which a plurality of solid state batteries according to the above embodiment are overlapped and current collectors are attached to both ends and both outer sides. The solid battery can be obtained.
The current collector may be made of a conductor, such as aluminum.

As the negative electrode material in the above step (1), a carbon fiber woven fabric was pressed and pressure-molded so that the intersecting portion of the warp yarn and the weft yarn had the same thickness as the other portion, and was flattened. Examples include woven fabrics. The warp and weft can form a square space (void) at a regular pitch. As the flattening, flattening and pressing can be performed by a flat press or a roll press. Further, depending on the material and the fiber diameter of the fiber, it can be flattened by applying heat and pressure.
A sheet obtained by pressure flattening a carbon fiber woven fabric containing a negative electrode active material, which can be suitably used in the embodiment of the present invention, obtained as described above, is a square formed by warp and weft, a wire diameter, When the gap (gap part) has the same size, it may have a square gap.

The carbon fiber in the embodiment of the present invention may be only the carbon of the negative electrode active material or a mixture of the negative electrode active material and a solid electrolyte.
If the eared portion of the woven fibrous electrode material in the step (1) is removed before attaching the current collector to the end portion, the steps (1) to ( It may be removed while proceeding to 2), or may be removed during the subsequent steps (2) to (3) or after step (3).

In the step (2), a solid electrolyte material is solidified by an arbitrary coating technique such as a sputtering method, a vapor deposition method or a sol-gel method around the surface including the negative electrode active material of the negative electrode material except for an end portion which becomes a negative electrode current collecting portion. An electrolyte layer can be laminated.
In the above step (2), it is preferable to deposit a solid electrolyte thin film around the carbon fibers formed in a lattice shape by sputtering or vapor-depositing a solid electrolyte material.

In the step (3), the powdery positive electrode material layer can be formed by coating the positive electrode material on both surfaces of the solid electrolyte layer including the voids which are lattice-like spaces by a method such as sol-gel method or coating. In the above-mentioned method, usually, after drying, pressurization or pressurization by the CIP method is performed to increase the filling rate of the positive electrode material.
In the step (4), a thin film of the current collector layer can be formed by sputtering or vapor-depositing a current collecting material such as aluminum or carbon on at least one surface of the powdery positive electrode material layer.

  The solid state battery according to the second embodiment of the present invention includes a step of preparing a positive electrode material obtained by pressing and flattening a woven fabric in which a positive electrode active material layer is laminated around a woven fibrous conductor ( 1) Step (2) of coating the solid electrolyte by removing the edge of the cathode active material layer from both sides of the sheet and laminating the electrolyte layer around the cathode active material surface, coating the anode material from both sides of the sheet, Step (3) of filling and laminating a powdery negative electrode material on the voids and solid electrolyte layers formed by pressure pressing and adjoining each other, and as shown in FIG. Can be obtained by a method including a step (4) of attaching a current collector to both the outer surface and the outer surface.

  As shown in the diagram on the left side of FIG. 5, a conventional flat plate lithium ion battery includes a positive electrode mixture layer (eg, 60 μm thick), an electrolyte layer (eg, 60 μm thick), and a negative electrode composite. A material layer (for example, a thickness of 70 μm) is laminated, and the electrolyte layer is thinned within a range that can ensure the role of the electrolyte layer for ensuring insulation, and is shown in the right side of FIG. Thus, the thickness of each layer can be 60 μm, 20 μm or less, 2 μm, and 70 μm, but the maximum distance between the positive electrode and the negative electrode is hardly reduced, and it is difficult to increase the output.

On the other hand, as shown in FIG. 6, in the conventional thin film battery, the thickness of each layer is 5 μm, 2 μm, and 5 μm, and the output density is improved, but the energy density is greatly reduced.
Thus, the conventional flat lithium ion battery and thin film battery have a problem that it is very difficult to have both a high output and a large amount of energy.

On the other hand, one of the three-dimensional solid batteries proposed to improve the problems of these conventional general lithium ion batteries and thin film batteries is that the positive electrode and the negative electrode face each other as shown in FIG. It is a solid state battery having a fixed electrode.
Such a solid battery having a three-dimensional shape is considered to have a pitch between electrodes of about 1 to 10 μm, and satisfies the above seven requirements.
However, the solid battery having the three-dimensional shape needs to fix both the positive electrode and the negative electrode first, and pack the solid electrolyte between the narrow electrode structures. It is envisaged.

The solid state battery according to the embodiment of the present invention can satisfy the above-mentioned seven requirements as described above, and can satisfy the eight requirements that a process involving difficulty is not required in manufacturing.
The fibrous conductor used in the solid state battery of the second embodiment of the present invention has a diameter or maximum diameter (maximum distance in a cross section when the cross section is not circular) of 100 nm to 100 μm, preferably It may be about 5 to 20 μm.
The positive electrode active material layer may have a thickness of 2 to 50 μm, particularly 2 to 10 μm when the positive electrode active material alone is formed, and 10 to 50 μm when the positive electrode active material and the solid electrolyte are formed.
In addition, the thickness of the solid electrolyte layer 11 in the first and second embodiments may be about 2 to 50 μm, particularly about 2 to 20 μm.

Examples of the fibrous conductor for the positive electrode in the embodiment of the present invention include SUS, carbon or aluminum fiber, preferably carbon or aluminum fiber, particularly carbon fiber.
In addition, examples of the fibrous conductor for the negative electrode in the second embodiment include copper, SUS, or carbon fibers, and preferably carbon fibers having low crystallinity.

In the embodiment of the present invention, the positive electrode active material layer may be formed only from the positive electrode active material, or may be formed from a mixture of the positive electrode active material and the solid electrolyte. When a mixture of a positive electrode active material and a solid electrolyte is used, the ratio of positive electrode active material: solid electrolyte may be 3: 7 to 9: 1 (vol ratio).
In addition, the negative electrode active material layer in another embodiment of the present invention may be formed only from the negative electrode active material or may be formed from a mixture of the negative electrode active material and the solid electrolyte. When using the mixture of a negative electrode active material and a solid electrolyte, negative electrode active material: solid electrolyte may be 3: 7-9: 1 (vol ratio).

Examples of the positive electrode active material or the negative electrode active material include lithium cobaltate (Li _x CoO ₂ ), lithium nickelate (Li _x NiO ₂ ), and nickel manganese lithium cobaltate (Li _{1 + x} Ni _1/3 Mn _1/3 Co _{1 / 3} O ₂ ), nickel nickel cobaltate (LiCo _0.3 Ni _0.7 O ₂ ), lithium manganate (Li _x Mn ₂ O ₄ ), lithium titanate (Li _4/3 Ti _5/3 O ₄ ) , Lithium manganate compound (Li _{1 + x} M _y Mn _2−xy O ₄ ; M = Al, Mg, Fe, Cr, Co, Ni, Zn), lithium titanate (Li _x TiO _y ), lithium metal phosphate _{(LiMPO 4, M = Fe,} Mn, Co, Ni), vanadium oxide _{(V 2 O} 5), molybdenum oxide _(MoO 3), titanium sulfide (TiS ), Lithium cobalt nitride (LiCoN), lithium silicon nitride (LiCoN), lithium metal, lithium alloy (LiM, M = Sn, Si , Al, Ge, Sb, P), lithium storage intermetallic compound (MgxM, M = Sn, Ge, Sb, or XySb, X = In, Cu, Mn) and derivatives thereof, and carbon materials (C) such as graphite and hard carbon. Here, there is no clear distinction between the positive electrode active material and the negative electrode active material, and the positive and negative potentials are compared for the positive electrode and the negative potential is used for the negative electrode by comparing the charge and discharge potentials of the two types of compounds. Thus, an electrode having an arbitrary voltage can be formed.

In particular, Li _x CoO ₂ , Li _x NiO ₂ , Li _x Mn ₂ O ₄ , Li _x Ni _1/2 Mn _1/2 O ₂ , Li _x Ni _1/3 Co _1/3 Mn _1/3 O ₂ , Li _x [Ni _y Li _{1 / 3-2y / 3} ] O ₃ (0 ≦ x ≦ 1, 0 <y <1/2) and lithium or transition metal of these lithium transition metal oxides were substituted with other elements Lithium transition metals such as LiNiMnCoO ₂ can be mentioned as the positive electrode active material.
In particular, carbon materials (C) such as graphite and hard carbon are preferably used as the negative electrode active material.

The solid electrolyte is not limited as long as it is a material that can be used as a solid electrolyte material of a lithium secondary battery, for example, Li ₂ O—B ₂ O ₃ —P ₂ O ₅ , Li ₂ O—SiO ₂ , Oxide-based amorphous solid electrolytes such as Li ₂ O—B ₂ O ₃ and Li ₂ O—B ₂ O ₃ —ZnO, Li ₂ S—SiS ₂ , LiI—Li ₂ S—SiS ₂ , liI-li _{2 S-P 2 S 5, LiI} -Li 2 S-B 2 S 3, Li 3 PO 4 -Li 2 S-Si 2 S, Li 3 PO 4 -Li 2 S-SiS 2, LiPO 4 -Li 2 S- _{SiS, LiI-Li 2 S-} P 2 O 5, LiI-Li 3 PO 4 -P 2 S 5, Li 3 PS 4, Li 2 S-P 2 S 5 the sulfide-based amorphous solid electrolytes such as, or _{LiI, LiI-Al 2 O 3} , L _{3 N, Li 3 N-LiI} -LiOH, Li 1.3 Al 0.3 Ti 0.7 (PO 4) 3, Li 1 + x + y A x Ti 2-x Si y P 3-y O 12 (A = Al or Ga, 0 ≦ x ≦ 0.4, 0 <y ≦ 0.6), [(B _1/2 Li _1/2 ) _1-z C _z ] TiO ₃ (B = La, Pr, Nd, Sm, C = Sr or Ba, 0 ≦ x ≦ 0.5), Li ₅ La ₃ Ta ₂ O ₁₂ , Li ₇ La ₃ Zr ₂ O ₁₂ , Li ₆ BaLa ₂ Ta ₂ O ₁₂ , Li ₃ PO _{(4-3 / 2w )} N _w (w <1), crystalline oxides such as Li _3.6 Si _0.6 P _0.4 O ₄ and oxynitrides.

Examples of the negative electrode material that provides the powdery negative electrode material layer in the embodiment of the present invention include a negative electrode active material and a solid electrolyte.
The proportion of each component may include 10 to 50 parts by mass of the solid electrolyte with respect to 100 parts by mass of the negative electrode active material.

Examples of the positive electrode material that provides the powdered electrode material layer in the present invention include a positive electrode active material and a solid electrolyte, and a powder (conductive material) of a highly conductive material that supplements the low conductivity of the positive electrode active material can be mixed. . Examples of the conductive material include various carbon blacks, for example, conductive powders such as acetylene black, furnace black, ketjen black, graphite, and activated carbon.
The proportion of each component may be 10 to 50 parts by mass of the solid electrolyte and 10% by mass or less, particularly 5% by mass or less of the conductive powder with respect to 100 parts by mass of the positive electrode or the negative electrode active material.

Examples of the lithium ion conductor of _the, LiTi 2 _{(PO 4) 3,} etc., or _{Li 2 O-B 2 O 3} -P 2 O 5, Li 2 O-SiO 2, Li 2 O-B 2 O 3, Li Oxide-based amorphous solid electrolyte such as ₂ O—B ₂ O ₃ —ZnO, LiI—Li ₂ S—P ₂ S ₅ , LiI—Li ₂ S—B ₂ S ₃ , Li ₃ PO ₄ —Li ₂ S _{-Si 2 S, Li 3 PO 4} -Li 2 S-SiS 2, LiPO 4 -Li 2 S-SiS, LiI-Li 2 S-P 2 O 5, LiI-Li 3 PO 4 -P 2 S 5, Li ₃ PS ₄ , sulfide-based amorphous solid electrolyte such as Li ₂ S—P ₂ S ₅ , LiNbO ₃ , or Li _1.3 Al _0.3 Ti _0.7 (PO ₄ ) ₃ , Li _{1 + x + y} A _x Ti _{2-x Si y P 3-} y O 12 A = Al or Ga, 0 ≦ x ≦ 0.4,0 < y ≦ 0.6), [(B 1/2 Li 1/2) 1-z C z] TiO 3 (B = La, Pr, Nd , Sm, C = Sr or Ba, 0 ≦ x ≦ 0.5), Li ₅ La ₃ Ta ₂ O ₁₂ , Li ₇ La ₃ Zr ₂ O ₁₂ , Li ₆ BaLa ₂ Ta ₂ O ₁₂ , Li ₃ PO _{(4 -3 / 2w) N w (w} <1), niobium such as crystalline oxide or oxynitride, such as _{Li 3.6 Si 0.6 P 0.4 O 4} , selected tantalum, silicon, phosphorus and boron And lithium-containing compounds containing at least one kind of element and lithium, LiI, LiI—Al ₂ O ₃ , LiN ₃ , Li ₃ N—LiI—LiOH, and the like.

  In the solid battery of the present invention, the end of the fibrous electrode material can be used as a current collector, and a stacked solid battery can be formed by stacking a desired number of solid batteries, so that the capacity can be increased. .

As described above, the solid battery according to the embodiment of the present invention satisfies the above seven requirements and does not require a difficult process in manufacturing, so that it can be easily manufactured.
The result of having examined the solid battery of the embodiment of this invention including the following simulations about satisfying said 8 requirements is shown.
1) Regarding Requirement 1 First, as for Requirement 1), the solid battery according to the embodiment of the present invention is obtained by coating the electrolyte layer with a thin film of about 2 μm, for example, by a vapor phase method such as sputtering or electroless plating. It can be easily satisfied by thinning.
2) About requirement 2

Regarding the above requirement 2), as shown in FIG. 8, when considering one unit, the area of the small battery is 1 cm ₂ and the positive electrode active material volume of the small battery = 1 cm ₂ × 0.0006 (60 μm) × 50% = 3 × 10 ^{− 3} cm ³ . The fiber length for obtaining an equivalent amount of positive electrode active material is 1.09 × 10 ⁴ , and the total fiber length is divided by the fiber length (30 μm) of one unit in FIG. , Calculating the area of the battery, and multiplying the thickness to calculate the volume, as shown in FIG. Therefore, it is possible to eliminate the decrease in energy density. Therefore, the same amount of the positive electrode and the negative electrode can be set, and the volume can be almost equal to that of the small battery.
Therefore, the solid state battery of the embodiment of the present invention can satisfy the requirement 2.

3) Regarding Requirements 3 to 5 As shown in FIG. 10, the solid battery of the embodiment of the present invention has a positive electrode film thickness of 2.5 μm due to thinning of the positive electrode active material layer and the powdery negative electrode material layer. The maximum thickness can be 3.65 μm, the maximum distance between the positive electrode and the negative electrode is small, the output density can be increased, and the solid electrolyte can be used, so the requirements 3 to 5 can be satisfied.

4) Regarding Requirement 6 The solid state battery according to the embodiment of the present invention has, for example, 15 stacked solid state batteries made of one sheet shown in FIG. 3, and the current collector thin film on the end portion and the powdery negative electrode material layer. Since a laminated solid battery can be obtained by attaching a current collector to, requirement 6 can be satisfied.

5) Regarding Requirement 7 Based on FIG. 11 showing the configuration between the members of the solid state battery of the embodiment of the present invention and FIG. 12 showing the configuration of the conventional small battery, the electronic conductivity and ionic conductivity of the electrode are determined. We examined what was kept.
The dimensions of the solid battery according to the embodiment of the present invention were changed, and the influence on the performance of the solid battery was verified.
(1) Verification 1
As the solid state battery of the embodiment of the present invention, the battery of Verification Example 1 whose schematic diagram is shown in FIG. 13 was verified.
The volume of the positive electrode active material of the conventional small battery was set to 1 cm ² × 0.006 × 50% = 3 × 10 ⁻³ cm ³ from the measurement of the produced sample.

The fiber length of the battery of Example 1 of the embodiment of the present invention for obtaining an equivalent amount of active material was determined, and the battery volume was calculated.
Active material amount = πx (8 ² -4 ² ) / 4xL
L = 3 × 10 ⁻³ / [πx (8 ² −4 ² ) / 4]
= 7.96 × 10 ³ (cm)
Number of units = 7.96 × 10 ³ ÷ 3.6 × 10 ⁻³ = 2.2 × 10 ⁶
Number of units / one side = (2.2 × 10 ⁶ ) ^1/2 = 1.48 × 10 ³
The length of one side of one unit = 1.48 × 10 ³ × 2.4 × 10 ⁻³ = 3.55 (cm)
In the case of a single plate battery Battery area S = (3.55) ² = 12.6 cm ²
Battery volume V = 12.6 × 3.2 × 10 ⁻³ = 0.0403 cm ³
In the case of a stacked plate battery: Battery area S = 1 cm ² Thickness t = 176 μm
Battery volume V = 1 cm ² x (13 sheets × 12 μm + 10 μm = 0.176 cm ³
The results are summarized and shown in Table 1 together with other results.

(1) Verification 2
As the solid state battery of the embodiment of the present invention, the battery of Verification Example 2 whose schematic diagram is shown in FIG. 14 was verified.
In the same manner as in verification 1, the following values were obtained.
L = 3.98 × 10 ³ (cm)
In the case of a single plate battery Battery area S = 9.55 cm ²
Battery volume V = 0.036 cm ³
In the case of a stacked plate battery: Battery area S = 1 cm ² Thickness t = 200 μm
Battery volume V = 0.02 cm ³
The results are summarized and shown in Table 1 together with other results.

From Table 1, since the solid battery of the embodiment of the present invention has a greatly increased contact area between each member and a greatly reduced maximum distance compared to a small battery, the electron conduction of the electrode Therefore, requirement 7 can be satisfied even though the property and the ionic conductivity are sufficiently maintained.
6) Regarding Requirement 8 As is clear from FIGS. 2A to 2E showing the process, the solid state battery according to the embodiment of the present invention is a process that involves difficulties such as filling a narrow space of a complicated shape with a powder material when manufacturing. Therefore, requirement 8 can be satisfied.

  According to the present invention, it is possible to obtain a solid state battery capable of increasing the capacity without requiring a process involving difficulty in manufacturing.

DESCRIPTION OF SYMBOLS 1 Solid battery of embodiment of this invention 2 Negative electrode material 3 The surface containing a negative electrode active material 4 The surface containing a positive electrode active material 4 'Positive electrode active material layer 5 End part 6 Solid electrolyte layer 7 Cavity part 8 Powdered positive electrode material layer 9 Powdered negative electrode material layer
11 Positive current collector layer
12 Negative electrode current collector layer
13 Negative electrode current collector
14 Positive current collector

Claims (8)

  A solid electrolyte layer having a surface containing an active material of either positive or negative pole around the woven fibrous electrode material, and surrounding the surface containing the active material except for an end of the electrode material Is a solid battery in which a gap is formed by solid electrolyte layers adjacent to each other and a powdered electrode material layer having a polarity different from that of the active material is filled and laminated on the solid electrolyte layer.   The solid battery according to claim 1, wherein the woven fibrous electrode material is made of carbon containing a negative electrode active material, and the dusty electrode material is a dusty positive electrode material layer.   A positive electrode active material layer is laminated around a fibrous conductor in which the woven fibrous electrode material is woven, and the dusty electrode material is a dusty negative electrode material. 1. The solid battery according to 1.   The solid battery according to claim 3, wherein the woven fibrous conductor is a carbon or aluminum fiber having a positive electrode active material layer laminated around it.   The solid battery according to any one of claims 1 to 4, wherein a current collector layer is laminated on one side of the powdery electrode material layer.   The solid battery according to any one of claims 1 to 5, wherein the woven fibrous electrode material is a sheet obtained by pressing and flattening a woven fabric made of an electrode material.   The solid battery according to any one of claims 1 to 6, wherein the woven fibrous electrode material has a void portion having a quadrangular cross section parallel to a surface woven as warp and weft.   6. An end of the woven fibrous electrode material and an end of a current collector layer laminated on at least one surface of the dusty electrode material layer are connected to each current collector. The solid battery according to any one of -7.

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