battery

Abstract

A battery of the present application has a hexahedron-shaped electrode laminate, a can that encloses the electrode laminate, and a heat spreader that contacts at least four faces of the can and the electrode laminate. The heat spreader is composed of a heat spread sheet.

Description

Technical Field

[0001] This invention relates to batteries. Background Technology

[0002] Solid-state batteries are known as safe lithium-ion secondary batteries.

[0003] Japanese Patent No. 7136708 discloses an all-solid-state battery cell (hereinafter also referred to as a "battery"). In this battery, an electrode stack is encapsulated in an outer casing material. The electrode stack has a current collector extending from its end. The current collector is connected to a terminal extending from the end of the battery. Inside the outer casing material, a first heat transfer material is disposed in contact with the electrode stack and the outer casing material. A heat dissipation member is disposed along the stacking direction of the electrode stack in a manner that covers the end face of the electrode stack. Summary of the Invention

[0004] Electrode stacks typically generate heat during charging or discharging. If the electrode stack has difficulty dissipating heat, problems may arise (e.g., shortened battery life). Therefore, batteries with high structural efficiency and efficient heat conduction between the outer casing and the electrode stack are required. "Structural efficiency" refers to the proportion of the battery's volume to the volume of its power-generating components.

[0005] The present invention was made in view of the above-mentioned actual situation. One embodiment of the present invention aims to solve the problem of providing a battery that can efficiently conduct heat between the outer can and the electrode stack and has excellent structural efficiency.

[0006] The means to solve the above problems include the following implementation methods.

[0007] The battery of type 1 has the following features:

[0008] Hexahedral electrode stack;

[0009] The outer packaging can encapsulates the electrode stack; and

[0010] A heat diffuser that is in contact with at least four surfaces of the outer can and the electrode stack.

[0011] The heat diffuser is composed of heat diffuser sheets.

[0012] A "heat diffuser sheet" refers to a sheet with a thermal conductivity of 100 W / mK or higher in the planar direction. The thermal conductivity of a heat diffuser sheet can be 2000 W / mK or lower. Heat diffusers can be self-supporting sheets. Heat diffusers do not include sheets containing resin (hereinafter also referred to as "thermal conductive sheets") (e.g., sheets made of resin, and sheets containing resin and thermally conductive fillers, etc.).

[0013] In the first embodiment, the battery has a heat diffuser in contact with at least four surfaces of the outer can and the electrode stack. The heat diffuser is composed of heat diffuser sheets. Even though the heat diffuser sheets are thinner than the heat-conducting sheets, they still have high thermal conductivity. As a result, the battery of the first embodiment is a battery that can efficiently conduct heat between the outer can and the electrode stack and has excellent structural efficiency.

[0014] The battery for the second method is:

[0015] According to the battery of the first embodiment, the heat diffuser surrounds the four sides of the electrode stack.

[0016] For the battery of the second type, compared with the case where the heat diffuser does not surround the four sides of the electrode stack, heat conduction between the outer can and the electrode stack can be more efficient.

[0017] The battery for the third method is:

[0018] According to the battery described in method 1 or method 2, wherein,

[0019] The thickness of the portion of the heat diffuser opposite to the stacked end face of the electrode laminate is greater than the thickness of the portion of the heat diffuser opposite to the stacked surface of the electrode laminate.

[0020] The electrode stack comprises, along the stacking direction, a first current collector, a first active material layer, a solid electrolyte layer, a second active material layer, and a second current collector in sequence.

[0021] The stacked end faces include the end face of the first current collector, the end face of the first active material layer, the end face of the solid electrolyte layer, the end face of the second active material layer, and the end face of the second current collector.

[0022] The stacked surface includes the surface of the electrode stack in the stacking direction.

[0023] The stacked end faces of the electrode stack tend to generate heat more easily during charging or discharging than the stacked surfaces. In the battery of the third type, the heat generated by charging or discharging in the electrode stack is easily and efficiently transferred through the outer can. As a result, in the battery of the third type, heat conduction between the outer can and the electrode stack can be more efficient.

[0024] The battery for the fourth method is:

[0025] The battery according to any one of the methods 1 to 3, wherein,

[0026] The heat diffusion sheet includes a heat diffusion layer and an electrically insulating layer formed on at least one main surface of the heat diffusion layer.

[0027] The heat diffusion layer comprises at least one of graphite sheets, aluminum foil, and copper foil.

[0028] The heat diffuser sheet is configured such that the electrical insulating layer is located on the side of the electrode stack.

[0029] In the fourth type of battery, short circuits in the electrode stack can be prevented more reliably.

[0030] The battery for method 5 is:

[0031] The battery according to any one of the methods 1 to 3, wherein,

[0032] The heat diffusion sheet consists of only a heat diffusion layer.

[0033] The heat diffusion layer comprises at least one of graphite sheets, aluminum foil, and copper foil.

[0034] An electrically insulating resin body is sandwiched between the stacked end face of the electrode laminate and the heat diffuser.

[0035] The electrode stack comprises, along the stacking direction, a first current collector, a first active material layer, a solid electrolyte layer, a second active material layer, and a second current collector in sequence.

[0036] The stacked end faces include the end face of the first current collector, the end face of the first active material layer, the end face of the solid electrolyte layer, the end face of the second active material layer, and the end face of the second current collector.

[0037] In the fifth method, the thickness of the heat diffuser sheet is thinner than the thickness of the heat diffuser sheet containing the electrical insulating layer. That is, the thickness of the battery in the stacking direction can be thinner in the fifth method. As a result, short circuits in the electrode stack can be prevented more reliably in the battery of the fifth method, and the volumetric efficiency of the battery is better.

[0038] According to the present invention, a battery with high thermal conductivity between the outer can and the electrode stack and excellent structural efficiency can be provided. Attached Figure Description

[0039] The features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will now be described with reference to the accompanying drawings, in which the same reference numerals denote the same elements, wherein:

[0040] Figure 1 This is a perspective view of the battery according to the first embodiment of the present invention.

[0041] Figure 2 yes Figure 1 Sectional view along line II-II.

[0042] Figure 3This is a cross-sectional view of the battery according to the second embodiment of the present invention.

[0043] Figure 4 This is a cross-sectional view of the battery according to the third embodiment of the present invention.

[0044] Figure 5 This is a cross-sectional view of the battery according to the fourth embodiment of the present invention.

[0045] Figure 6 This is a cross-sectional view of the battery according to the fifth embodiment of the present invention. Detailed Implementation

[0046] In the numerical ranges recorded in segments in this invention, the upper or lower limit value recorded in a certain numerical range can be replaced with the upper or lower limit value of other numerical ranges recorded in segments.

[0047] Hereinafter, embodiments of the battery of the present invention will be described with reference to the accompanying drawings. In the drawings, the same or equivalent parts are labeled with the same reference numerals and repeated descriptions are omitted.

[0048] (1) First implementation method

[0049] The battery 1A in the first embodiment is a solid-state battery. For example... Figure 1 As shown, battery 1A includes an electrode stack 10A, an outer casing 20, and a heat diffuser 30A (see reference). Figure 2 ), two positive terminals 41 and two negative terminals 42. The electrode stack 10A is a cuboid (an example of a hexahedral shape).

[0050] In the first embodiment, the length direction of the main surface, i.e., the stacking surface S10A, of the electrode stack 10A is defined as the X-axis direction. The width direction of the stacking surface S10A of the electrode stack 10A is defined as the Y-axis direction. The thickness direction of the electrode stack 10A is defined as the Z-axis direction (an example of the stacking direction). The X-axis, Y-axis, and Z-axis are orthogonal to each other. The X-axis direction is an example of an axial direction. It should be noted that these directions do not limit the orientation of the battery of the present invention during use.

[0051] Two positive terminals 41, electrode laminate 10A, and two negative terminals 42 are arranged in this order along the positive X-axis. The two positive terminals 41 and two negative terminals 42 are electrically connected to the electrode laminate 10A. The heat diffuser 30A contacts and surrounds the four faces of the outer canister 20 and the electrode laminate 10A (i.e., laminated surfaces S10A, S10B and laminated end faces S10C, S10D). The outer canister 20 encloses the electrode laminate 10A.

[0052] (1.1) Electrode stack

[0053] The electrode stack 10A functions as a power generation element of the battery 1A. The electrode stack 10A comprises two or more unit electrode bodies 10U. The two or more unit electrode bodies 10U are stacked along the Z-axis direction. The two or more unit electrode bodies 10U are connected in parallel.

[0054] The stacked structure of the unit electrode 10U is a unipolar structure. The unit electrode 10U is formed by stacking the positive current collector 101, the positive active material layer 102, the solid electrolyte layer 103, the negative active material layer 104, the negative current collector 105, the negative active material layer 104, the solid electrolyte layer 103, the positive active material layer 102, and the positive current collector 101 in this order along the Z-axis direction.

[0055] The positive current collector 101 collects electricity from the positive active material layer 102. Examples of materials that can be used for the positive current collector include stainless steel, aluminum, copper, nickel, iron, titanium, carbon, and aluminum alloys. The shape of the positive current collector 101 can be, for example, foil or mesh.

[0056] The positive electrode active material layer 102 contains a positive electrode active material, and may further contain at least one of a solid electrolyte, a conductive material, and a binder as needed.

[0057] The preferred positive electrode active material is a lithium composite oxide. Examples of lithium composite oxides include rock salt layered active materials, spinel-type active materials, and olivine-type active materials. The positive electrode active material can be any known positive electrode active material.

[0058] Examples of solid electrolytes include sulfide solid electrolytes, oxide solid electrolytes, nitride solid electrolytes, and halide solid electrolytes. Solid electrolytes can be any known type of solid electrolyte.

[0059] Examples of conductive materials include carbon materials, metal particles, and conductive polymers. Examples of carbon materials include acetylene black and carbon fibers.

[0060] Examples of adhesives include halogenated vinyl resins (e.g., polyvinylidene fluoride) and rubbers (e.g., butadiene acrylate rubber).

[0061] The solid electrolyte layer 103 contains a solid electrolyte and may further contain a binder if necessary. The solid electrolyte and binder are the same as those examples that may be included in the positive electrode active material layer 102.

[0062] The negative electrode active material layer 104 contains a negative electrode active material, and may further contain at least one of a solid electrolyte, a conductive material, and a binder as needed.

[0063] Examples of anode active materials include Li-based active materials (e.g., lithium metal), carbon-based active materials (e.g., graphite), oxide-based active materials (e.g., lithium titanate), and Si-based active materials (e.g., elemental Si).

[0064] The solid electrolyte, conductive material, and binder are the same as those examples that can be included in the positive electrode active material layer 102.

[0065] The negative electrode current collector 105 collects electricity from the negative electrode active material layer 104. Examples of materials that can be used for the negative electrode current collector include stainless steel, aluminum, copper, nickel, iron, titanium, carbon, and aluminum alloys. The shape of the negative electrode current collector 105 can be, for example, foil or mesh.

[0066] Electrode laminate 10A is a cuboid shape. For example... Figure 2 As shown, the electrode stack 10A has stacked surfaces S10A and S10B, stacked end surfaces S10C and S10D, and a pair of stacked end surfaces (not shown). Stacked surfaces S10A and S10B are opposite each other in the Z-axis direction. Stacked end surfaces S10C and S10D are opposite each other in the Y-axis direction. The pair of stacked end surfaces (not shown) are opposite each other in the X-axis direction.

[0067] In the first embodiment, the laminated surfaces S10A and S10B are formed by the positive current collector 101. The laminated end surfaces S10C and S10D are formed by the end surfaces of each layer constituting the unit electrode body 10U. That is, the laminated end surfaces S10C and S10D include the end surface of the positive current collector 101, the end surface of the positive active material layer 102, the end surface of the solid electrolyte layer 103, the end surface of the negative active material layer 104, and the end surface of the negative current collector 105. On the laminated end surfaces S10C and S10D, by a single cut, the end surfaces of each layer constituting the unit electrode body 10U are located on the same plane.

[0068] (1.2) Outer packaging tank

[0069] The outer container 20 is a metal container. The outer container 20 may have an electrically insulating film on its inner wall opposite to the electrode laminate 10A. The outer container 20 may be a known type of outer container.

[0070] (1.3) Thermal diffuser

[0071] The heat diffuser 30A enables efficient heat conduction between the outer can 20 and the electrode stack 10A. Furthermore, in the first embodiment, the heat diffuser 30A electrically insulates the electrode stack 10A from the outer can 20. The heat diffuser 30A is in physical contact with both the outer can 20 and the electrode stack 10A.

[0072] The heat diffuser 30A is composed of a heat diffuser sheet 300A. In the first embodiment, the heat diffuser 30A is formed by winding the heat diffuser sheet 300A around the four sides of the electrode stack 10A.

[0073] like Figure 2 As shown, the heat diffuser 300A has a heat diffuser layer 301 and an electrically insulating layer 302 formed on a main surface S301 of the heat diffuser layer 301. The heat diffuser 300A is configured such that the electrically insulating layer 302 is located on the electrode stack 10A side.

[0074] The heat diffusion layer 301 comprises at least one of graphite sheet, aluminum foil, and copper foil. The heat diffusion layer 301 can be a single layer or multiple layers. Materials for the electrical insulation layer 302 include resin and ceramics. The electrical insulation layer 302 can be adhesive or bondable. The thickness L300 of the heat diffusion sheet 300A (refer to...) Figure 2 The thickness of the heat diffusion layer 301 can be appropriately selected based on the material of the heat diffusion sheet 300A, ranging from 10μm to 1000μm or from 10μm to 400μm. The thickness L301 of the heat diffusion layer 301 (refer to...) Figure 2 The thickness L302 can be greater or less than the thickness of the electrical insulation layer 302 (refer to...). Figure 2 The thickness L301 of the heat diffusion layer 301 can be from 10 μm to 700 μm, from 10 μm to 300 μm, or from 10 μm to 50 μm. The heat diffusion sheet 300A can be a known heat diffusion sheet. From the viewpoint of further improving volumetric efficiency, the heat diffusion layer 301 preferably comprises a graphite sheet with a relatively thin thickness (e.g., 10 μm to 50 μm).

[0075] (1.4) Negative and Positive Extremes

[0076] The positive terminal 41 and the negative terminal 42 are used to conduct the power generated by the electrode stack 10A to the outside of the battery 1A. The positive terminal 41 and the negative terminal 42 can be known terminals.

[0077] (1.5) Effects

[0078] For reference Figure 1 and Figure 2 As described, battery 1A includes an electrode stack 10A, an outer casing 20, and a heat diffuser 30A. The heat diffuser 30A is composed of a heat diffuser sheet 300A.

[0079] Even though the heat diffuser 300A is thinner than the heat conductor, it still has high thermal conductivity. As a result, the battery 1A is a battery with excellent structural efficiency, capable of efficient heat conduction between the outer casing 20 and the electrode stack 10A.

[0080] For reference Figure 1and Figure 2 As explained, in battery 1A, the thermal diffuser 30A surrounds the four sides of the electrode stack 10A.

[0081] For battery 1A, compared to the case where the heat diffuser 30A does not surround the four sides of the electrode stack 10A, heat conduction between the outer can 20 and the electrode stack 10A can be performed more efficiently.

[0082] For reference Figure 1 and Figure 2 As explained, in battery 1A, heat diffuser 300A includes a heat diffuser layer 301 and an electrical insulating layer 302. The heat diffuser layer 301 includes at least one of graphite sheet, aluminum foil, and copper foil. The heat diffuser 300A is configured such that the electrical insulating layer 302 is located on the electrode stack 10A side.

[0083] In battery 1A, short circuits in electrode stack 10A can be prevented more reliably.

[0084] (2) Second implementation method

[0085] The battery 1B of the second embodiment is the same as the battery 1A except for the thickness of the heat diffuser.

[0086] Battery 1B comprises an electrode stack 10A, an outer can 20, and a heat diffuser 30B (see reference). Figure 3 ), two positive extremes 41 and two negative extremes 42.

[0087] like Figure 3 As shown, the heat diffuser 30B is composed of a heat diffuser sheet 300A. In the second embodiment, the heat diffuser 30B is formed by partially wrapping the heat diffuser sheet 300A around the four faces of the electrode stack 10A twice. The thickness L300B of the portion of the heat diffuser 30B opposite to the stacked end faces S10C and S10D of the electrode stack 10A (see reference). Figure 3 The thickness L300A of the portion of the heat diffuser 30B opposite to the lamination surfaces S10A and S10B of the electrode laminate 10A (refer to...) Figure 3 Thickness L300B is, for example, twice the thickness of thickness L300A.

[0088] (2.1) Effects

[0089] Battery 1B is identical to Battery 1A except that the heat diffuser 30A is replaced with heat diffuser 30B. Therefore, Battery 1B can perform the same function as Battery 1A.

[0090] For reference Figure 3As explained, the thickness L300B of the portion of the heat diffuser 30B opposite to the stacked end faces S10C and S10D of the electrode laminate 10A is thicker than the thickness L300B of the portion of the heat diffuser 30B opposite to the stacked surfaces S10A and S10B of the electrode laminate 10A.

[0091] The stacked end faces S10C and S10D of the electrode stack 10A tend to generate heat more easily during charging or discharging than the stacked surfaces S10A and S10B. In the battery 1B, the heat generated by charging or discharging in the electrode stack 10A is easily and efficiently transferred through the outer casing 20. As a result, heat conduction between the outer casing 20 and the electrode stack 10A is more efficient in the battery 1B.

[0092] (3) Third implementation method

[0093] The battery 1C of the third embodiment is the same as the battery 1A except that the heat diffusion sheet is different and an electrically insulating resin body is formed.

[0094] Battery 1C comprises an electrode laminate 10A, an outer can 20, a heat diffuser 30C, and an electrically insulating resin body 31 (see reference). Figure 4 It has two positive terminals 41 and two negative terminals 42. The electrically insulating resin body 31 is sandwiched between the stacked end faces S10C and S10D of the electrode laminate 10A and the heat diffuser 30C.

[0095] (3.1) Thermal diffuser

[0096] The heat diffuser 30C is composed of a heat diffuser sheet 300B. In the third embodiment, the heat diffuser 30C is formed by winding the heat diffuser sheet 300B around all four sides of the electrode stack 10A. Figure 4 As shown, the heat diffusion sheet 300B consists only of the heat diffusion layer 301.

[0097] (3.2) Electrically insulating resin body

[0098] The electrically insulating resin body 31 prevents short circuits in the electrode laminate 10A (e.g., short circuits between the positive electrode active material layer 102 and the negative electrode active material layer 104). The electrically insulating resin body 31 contains known resins (thermoplastic resins and thermosetting resins, etc.). Thermoplastic resins can be elastomers. From the viewpoint of making heat conduction between the outer can 20 and the electrode laminate 10A more efficient, the electrically insulating resin body 31 may contain thermally conductive fillers. Examples of materials that can be used as thermally conductive fillers include metal oxides (e.g., aluminum oxide, silicon dioxide, and magnesium oxide), metal nitrides (e.g., aluminum nitride, silicon nitride, and boron nitride), synthetic diamond, and silicon carbide. The electrically insulating resin body 31 can be a thin film (i.e., a self-supporting film) or a shaped paste.

[0099] (3.3) Effects

[0100] Battery 1C is identical to battery 1A except that the heat diffuser 30A is replaced with heat diffuser 30C and an electrically insulating resin body 31 is formed. Therefore, battery 1C can perform the same function as battery 1A.

[0101] For reference Figure 4 As explained, in battery 1C, the heat diffuser 300B consists only of a heat diffuser layer 301. The heat diffuser layer 301 comprises at least one of graphite sheet, aluminum foil, and copper foil. An electrically insulating resin body 31 is sandwiched between the stacked end faces S10C and S10D of the electrode stack 10A and the heat diffuser 30C.

[0102] The thickness L301 of the heat diffuser 300B is thinner than the thickness L300A of the heat diffuser 300A containing the electrical insulating layer 302. In other words, the thickness of the battery 1C in the Z-axis direction (i.e., the stacking direction) can be thinner. As a result, in the battery 1C, not only can short circuits in the electrode stack 10A be prevented more reliably, but the volumetric efficiency of the battery 1C is also superior.

[0103] (4) Fourth Implementation

[0104] The battery 1D of the fourth embodiment is the same as the battery 1A, except that the heat diffusion sheet is different and an electrically insulating resin body is formed.

[0105] Battery 1D comprises an electrode stack 10B, an outer can 20, a heat diffuser 30C, and an electrically insulating resin body 32 (see reference). Figure 5 ), two positive terminals 41 and two negative terminals 42. The electrically insulating resin body 32 is sandwiched between the stacked end faces S10C and S10D of the electrode laminate 10B and the heat diffuser 30C.

[0106] (4.1) Electrode stack

[0107] like Figure 5 As shown, the electrode stack 10B is the same as the electrode stack 10A except that the end faces of each layer constituting the unit electrode 10U at the stack end faces S10C and S10D are not on the same plane.

[0108] (4.2) Electrically insulating resin body

[0109] The electrically insulating resin body 32 prevents short circuits in the electrode stack 10B (e.g., short circuits between the positive electrode active material layer 102 and the negative electrode active material layer 104). The electrically insulating resin body 32 can be the same as the example of the electrically insulating resin body 31. The electrically insulating resin body 32 can be a molded form of a paste.

[0110] (4.3) Effects

[0111] Battery 1D is identical to battery 1C except that electrode laminate 10A is replaced by electrode laminate 10B and an electrically insulating resin body 31 is formed instead of the electrically insulating resin body 31. Therefore, battery 1D can perform the same function as battery 1C.

[0112] For reference Figure 5 As explained, in battery 1D, the electrically insulating resin body 32 is sandwiched between the stacked end faces S10C and S10D of the electrode laminate 10B and the heat diffuser 30C. Therefore, it is less likely for voids to form between the electrode laminate 10B and the heat diffuser 30C. As a result, compared to the case where voids form between the electrode laminate 10B and the heat diffuser 30C, heat conduction between the outer casing 20 and the electrode laminate 10B is more efficient in battery 1D.

[0113] (5) Fifth Implementation

[0114] The battery 1E of the fifth embodiment is the same as the battery 1A except that it has an electrically insulating resin body.

[0115] Battery 1E comprises an electrode stack 10A, an outer can 20, a heat diffuser 30A, and an electrically insulating resin body 33 (see reference). Figure 6 ), two positive terminals 41 and two negative terminals 42. The electrically insulating resin body 33 is sandwiched between the portion of the heat diffuser 30A opposite to the laminated end faces S10C and S10D and the outer can 20.

[0116] (5.1) Electrically insulating resin body

[0117] The electrically insulating resin body 33 reliably prevents the electrode laminate 10A from being electrically connected to the outer can 20. The electrically insulating resin body 33 can be the same as the example of the electrically insulating resin body 31. The electrically insulating resin body 31 can be a processed film (i.e., a self-supporting film) or a molded body of a paste.

[0118] (5.2) Effects

[0119] Battery 1E is identical to battery 1A except that it has an electrically insulating resin body 33 instead of an electrically insulating resin body 31. Therefore, battery 1E can perform the same function as battery 1A.

[0120] For reference Figure 6As explained, in battery 1E, the electrically insulating resin body 33 is sandwiched between the portion of the heat diffuser 30A opposite to the laminated end faces S10C and S10D and the outer canister 20. Therefore, it is less likely for a gap to form between the heat diffuser 30A and the outer canister 20. As a result, compared to the case where a gap forms between the heat diffuser 30A and the outer canister 20, heat conduction between the outer canister 20 and the electrode laminate 10A is more efficient in battery 1E.

[0121] (6) Variations

[0122] In batteries 1A to 1E, heat diffusers 30A, 30B, and 30C surround the four sides of electrode stacks 10A and 10B, but the present invention is not limited thereto. In the present invention, the heat diffusers may not surround the four sides of the electrode stacks.

[0123] In batteries 1A to 1E, the heat diffusion layer 301 comprises at least one of graphite sheet, aluminum foil, and copper foil, but the present invention is not limited thereto. In the present invention, the heat diffusion layer may not comprise at least one of graphite sheet, aluminum foil, and copper foil, provided that the thermal conductivity in the planar direction of the heat diffusion sheet is 100 W / mK or higher.

[0124] In batteries 1A to 1E, the electrode stacks 10A and 10B are cuboid in shape, but the present invention is not limited thereto. In the present invention, the electrode stacks can also be cubic in shape.

[0125] In batteries 1A to 1E, the charge carrier ions of electrode stacks 10A and 10B are lithium ions, but the present invention is not limited thereto. In the present invention, the charge carrier ions of the electrode stacks can also be sodium ions.

Claims

1. A type of battery, It possesses: Hexahedral electrode stack; The outer packaging can encapsulates the electrode stack; and A heat diffuser that is in contact with at least four surfaces of the outer can and the electrode stack. The heat diffuser is composed of heat diffuser sheets.

2. The battery according to claim 1, wherein, The thermal diffuser surrounds the four sides of the electrode stack.

3. The battery according to claim 1, wherein, The thickness of the portion of the heat diffuser opposite to the stacked end face of the electrode laminate is greater than the thickness of the portion of the heat diffuser opposite to the stacked surface of the electrode laminate. The electrode stack comprises, along the stacking direction, a first current collector, a first active material layer, a solid electrolyte layer, a second active material layer, and a second current collector in sequence. The stacked end faces include the end face of the first current collector, the end face of the first active material layer, the end face of the solid electrolyte layer, the end face of the second active material layer, and the end face of the second current collector. The stacked surface includes the surface of the electrode stack in the stacking direction.

4. The battery according to claim 1, wherein, The heat diffusion sheet includes a heat diffusion layer and an electrically insulating layer formed on at least one main surface of the heat diffusion layer. The heat diffusion layer comprises at least one of graphite sheets, aluminum foil, and copper foil. The heat diffuser sheet is configured such that the electrical insulating layer is located on the side of the electrode stack.

5. The battery according to claim 1, wherein, The heat diffusion sheet consists of only a heat diffusion layer. The heat diffusion layer comprises at least one of graphite sheets, aluminum foil, and copper foil. An electrically insulating resin body is sandwiched between the stacked end face of the electrode laminate and the heat diffuser. The electrode stack comprises, along the stacking direction, a first current collector, a first active material layer, a solid electrolyte layer, a second active material layer, and a second current collector in sequence. The stacked end faces include the end face of the first current collector, the end face of the first active material layer, the end face of the solid electrolyte layer, the end face of the second active material layer, and the end face of the second current collector.

Images