All-solid-state battery

Abstract

The invention provides an all-solid-state battery capable of improving electrical connection reliability in a collector structure. An all-solid-state battery (1) is provided with a case (10) having a recessed container (11) and a lid material (12) for covering the opening of the recessed container (11), a power generation element (20) housed in the case (10) and in which an electrode layer (21), an electrode layer (22) and a solid electrolyte layer (23) are laminated, and an elastic conductive member (30) disposed between the power generation element (20) and the inner bottom surface of the recessed container (11). The elastic conductive member (30) is press-fitted together with the power generating element (20) and housed inside the recessed container (11). The electrode layer (21) includes an electrode mixture layer (211) and a porous metal layer (212). The elastic conductive member (30) is in contact with the porous metal layer (212) and presses the power generating element (20) in the direction of the cover material (12) by the elastic force of the elastic conductive member (30). In addition, all-solid batteries of the invention relate to targets 7 and 12 of SDGs.

Description

Technical Field

[0001] The present disclosure relates to an all-solid-state battery in which a power generation element is sealed in a casing. Background Art

[0002] In recent years, with the development of portable electronic devices such as mobile phones and notebook personal computers, and the practical application of electric vehicles, there is a demand for small and lightweight secondary batteries with high capacity and high energy density. At present, in non-aqueous secondary batteries that can meet this requirement, lithium-containing composite oxides such as lithium cobalt oxide (LiCoO2) and lithium nickel oxide (LiNiO2) are used as positive electrode active materials, graphite as negative electrode active materials, and organic electrolytes containing organic solvents and lithium salts as non-aqueous electrolytes. With the development of application equipment for non-aqueous secondary batteries, there is a demand for further long life, high capacity and high energy density of non-aqueous secondary batteries, and high reliability of non-aqueous secondary batteries.

[0003] However, the organic electrolyte contains an organic solvent as a flammable substance. Therefore, when an abnormal situation such as a short circuit occurs in the battery, the organic electrolyte may generate abnormal heat. In addition, in recent years, in view of the high energy density of non-aqueous secondary batteries and the increasing trend of the amount of organic solvent in the organic electrolyte, the reliability of non-aqueous secondary batteries is further required.

[0004] Under such circumstances, all-solid secondary batteries that do not use organic solvents have been studied. In all-solid secondary batteries, a power generation element (electrode stack) is formed by stacking a molded body of a solid electrolyte that does not use an organic solvent with a molded body of an electrode mixture of each of the positive and negative electrodes instead of the conventional organic solvent-based electrolyte. Therefore, in all-solid secondary batteries, there is no worry that the solid electrolyte will generate abnormal heat, and it has high reliability.

[0005] In such all-solid-state secondary batteries, various methods have been proposed for ensuring current collection performance between a power-generating element and a conductor portion provided in a case that houses the power-generating element.

[0006] Patent document 1 (International Publication No. 2012 / 141231) discloses a solid battery. The solid battery comprises: a battery body comprising a positive electrode layer, a solid electrolyte layer and a negative electrode layer; a storage member that houses the battery body and comprises a conductor portion; and a positive terminal and a negative terminal arranged on the outer surface of the storage member. The solid battery also comprises a current collecting member, which is arranged between at least one of the positive electrode layer or the negative electrode layer and the storage member in a manner connected to the conductor portion of the storage member, has elasticity and contains a conductive substance. The current collecting member preferably comprises, for example, at least one of a carbon material or a conductive rubber, and preferably comprises either a carbon sheet or an anisotropic conductive rubber sheet. Thus, the solid battery can maintain good electrical connection with the electrode layer of the battery body.

[0007] Patent document 2 (Japanese Patent Publication No. 2010-165681) discloses a galvanic element. The galvanic element includes a cathode, an anode, an electrolyte, a separator arranged between the cathode and the anode, and a casing. Although the galvanic element is not an all-solid-state battery, it includes at least one conductive spring element. The conductive spring element presses the cathode or the anode toward the separator using a conductive intermediate element. The conductive spring element improves the reliability of the electrical contact between the electroactive material of the cathode or the anode on one side and the casing on the other side.

[0008] Prior art literature

[0009] Patent Literature

[0010] Patent Document 1: International Publication No. 2012 / 141231

[0011] Patent Document 2: Japanese Patent Application Publication No. 2010-165681 Summary of the invention

[0012] As described above, the current collecting member of Patent Document 1 and the conductive spring element of Patent Document 2 improve reliability in electrical connection. However, in view of the recent demand for small and lightweight secondary batteries with high capacity and high energy density, further improvement in electrical connection reliability in all-solid batteries is required.

[0013] Therefore, an object of the present disclosure is to provide an all-solid-state battery having a high electrical connection reliability in a current collecting structure.

[0014] In order to solve the above-mentioned problems, the present disclosure is constituted as follows. That is, the all-solid battery of the present disclosure may have a shell, a power generation element and an elastic conductive member, the shell having a concave container with a bottom and a side wall portion and a cover material covering the opening of the concave container, the power generation element is sealed in the shell, and has a first electrode layer arranged on the bottom side, a second electrode layer arranged on the cover material side, and a solid electrolyte layer arranged between the first electrode layer and the second electrode layer, and the elastic conductive member is arranged between the power generation element and the inner bottom surface of the bottom of the concave container. The first electrode layer may include a first electrode mixture layer and a first porous metal layer arranged between the first electrode mixture layer and the elastic conductive member, and is electrically connected to a first conductive path from the inside of the shell to the outside via the elastic conductive member. The second electrode layer may include a second electrode mixture layer and a second porous metal layer arranged between the second electrode mixture layer and the cover material, and is electrically connected to a second conductive path from the inside of the shell to the outside. At least a portion of the first porous metal layer may be buried in the surface layer of the first electrode mixture layer and integrated with the first electrode mixture layer. The end of the first porous metal layer on the opposite side to the first electrode mixture layer may be exposed on the surface of the first electrode layer. At least a portion of the second porous electrode layer may be buried in the surface layer of the second electrode mixture layer and integrated with the second electrode mixture layer. The end of the second porous metal layer on the opposite side to the second electrode mixture layer may be exposed on the surface of the second electrode layer. The elastic conductive member may contact the first porous metal layer to press the power generation element toward the cover material.

[0015] According to the all-solid-state battery disclosed herein, the reliability of electrical connection can be improved in the current collection structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] FIG. 1 is a cross-sectional view showing an all-solid-state battery according to a first embodiment of the present disclosure.

[0017] FIG. 2 is a perspective view showing a concave container of the all-solid-state battery of FIG. 1 .

[0018] FIG. 3 is a plan view showing the all-solid-state battery of FIG. 1 (excluding the cover material and the conductive plate).

[0019] FIG. 4 is a plan view showing the all-solid-state battery of FIG. 1 (excluding the cover material, the conductive plate, and the power generation element).

[0020] FIG. 5 is a cross-sectional view showing a state where a power generating element and an elastic conductive member are housed inside a concave container.

[0021] FIG. 6 is a perspective view showing the conductive plate shown in FIG. 1 .

[0022] FIG. 7 is a cross-sectional view showing an all-solid-state battery including an elastic conductive member according to Modification 1. FIG.

[0023] FIG. 8 is a perspective view showing the elastic conductive member shown in FIG. 7 .

[0024] FIG. 9 is a perspective view showing an elastic conductive member according to Modification 2. FIG.

[0025] FIG. 10 is a perspective view showing an elastic conductive member according to Modification 3. FIG.

[0026] FIG. 11 is a cross-sectional view showing an all-solid-state battery according to a second embodiment.

[0027] FIG. 12 is a graph showing a method of obtaining a spring constant. DETAILED DESCRIPTION

[0028] The inventors of the present invention have conducted in-depth research and found that, compared with directly contacting the conductive elastic member with the surface of the molded body of the electrode mixture containing the active material, contacting the conductive elastic member with the porous metal substrate disposed on the surface of the molded body of the electrode mixture can more fully reduce the internal resistance, and can more fully absorb the deviation of the thickness of the power generation element or the height of the shell, thereby reducing the deviation of the internal resistance value. The present disclosure is made in view of such a situation.

[0029] (Composition 1)

[0030] The all-solid battery of the embodiment of the present disclosure may include a shell, a power generation element, and an elastic conductive member, wherein the shell includes a concave container having a bottom and a side wall portion and a cover material covering the opening of the concave container, the power generation element is sealed in the shell, and has a first electrode layer arranged on the bottom side, a second electrode layer arranged on the cover material side, and a solid electrolyte layer arranged between the first electrode layer and the second electrode layer, and the elastic conductive member is arranged between the power generation element and the inner bottom surface of the bottom of the concave container. The first electrode layer may include a first electrode mixture layer and a first porous metal layer arranged between the first electrode mixture layer and the elastic conductive member, and is electrically connected to a first conductive path from the inside of the shell to the outside via the elastic conductive member. The second electrode layer may include a second electrode mixture layer and a second porous metal layer arranged between the second electrode mixture layer and the cover material, and is electrically connected to a second conductive path from the inside of the shell to the outside. At least a portion of the first porous metal layer may be buried in the surface layer of the first electrode mixture layer and integrated with the first electrode mixture layer. The end of the first porous metal layer on the opposite side of the first electrode mixture layer may be exposed on the surface of the first electrode layer. At least a portion of the second porous electrode layer may be embedded in the surface layer of the second electrode mixture layer and integrated with the second electrode mixture layer. The end of the second porous metal layer on the opposite side of the second electrode mixture layer may be exposed on the surface of the second electrode layer. The elastic conductive member may contact the first porous metal layer to press the power generation element toward the cover material.

[0031] Thus, the all-solid-state battery 1 can sufficiently reduce the internal resistance, and can also sufficiently absorb the variation in the thickness of the power generation element and the height of the housing, thereby reducing the variation in the internal resistance value. As a result, the electrical connection reliability of the all-solid-state battery can be improved.

[0032] (Composition 2)

[0033] In the all-solid battery of Configuration 1, the elastic conductive member may be a metal spring. This allows electrical connection with lower internal resistance than when conductive rubber, carbon sheet, or the like is used as the elastic conductive member.

[0034] (Composition 3)

[0035] In the all-solid battery of configuration 1, the elastic conductive member may have a flat portion in contact with the first porous metal layer and a leg portion extending toward the inner bottom surface of the bottom of the concave container. Thus, the elastic force of the elastic conductive member can be used to appropriately press the power generation element toward the cover material, and the contact area with the first electrode layer can be expanded, so that a good electrical connection can be maintained.

[0036] (Composition 4)

[0037] In the all-solid battery of Configuration 1, the elastic conductive member may be a disc spring. Thus, even if the volume occupied by the elastic conductive member in the internal space of the case 10 is reduced, the power generating element can be sufficiently pressed toward the cover member.

[0038] (Composition 5)

[0039] In the all-solid battery of configuration 1, the elastic conductive member may be a corrugated washer. Thus, the inner bottom surface of the bottom of the power generation element or the concave container is in surface contact with the corrugated washer at multiple locations, thereby maintaining good electrical connection. In addition, the corrugated washer does not have a sharp front end formed by interruption in the middle, thereby reducing the risk of damaging the power generation element.

[0040] (Composition 6)

[0041] In the all-solid battery of configuration 1, the elastic conductive member may be a conical spring. Thus, the inner bottom surface of the bottom of the power generation element or the concave container is in annular contact with the conical spring, so even if the volume occupied by the elastic conductive member in the internal space of the housing 10 is further reduced, the power generation element can be fully pressed toward the cover material, and good electrical connection can be maintained.

[0042] (Composition 7)

[0043] In any of the all-solid batteries in configurations 1 to 6, the all-solid battery may further include a conductive plate between the power generation element and the cover material. The conductive plate may prevent the power generation element pressed by the elastic conductive member from moving toward the cover material. The second electrode layer may be electrically connected to the second conduction path via the conductive plate. A gap may be formed between the conductive plate and the cover material. Thus, deformation of the cover material caused by pressure from the elastic conductive member or load on the joint between the concave container and the cover material may be prevented. In addition, since the cover material is not conductive to the power generation element, the cover material may have no potential.

[0044] (Composition 8)

[0045] Another embodiment of the present disclosure is a fully solid battery having a shell, a power generation element, an elastic conductive member, and a conductive plate, wherein the shell has a concave container having a bottom and a side wall portion and a cover material covering the opening of the concave container, the power generation element is sealed in the shell, and has a first electrode layer arranged on the bottom side, a second electrode layer arranged on the cover material side, and a solid electrolyte layer arranged between the first electrode layer and the second electrode layer, the elastic conductive member is arranged between the power generation element and the inner bottom surface of the bottom of the concave container, and the conductive plate is arranged between the power generation element and the above-mentioned cover material. The first electrode layer is electrically connected to a first conductive path from the inside of the shell to the outside via the elastic conductive member. The second electrode layer is electrically connected to a second conductive path from the inside of the shell to the outside via the conductive plate. The elastic conductive member contacts the above-mentioned first electrode layer to press the power generation element toward the cover material. The conductive plate contacts the above-mentioned second electrode layer to prevent the above-mentioned power generation element from moving toward the above-mentioned cover material. The spring constant of the conductive plate is greater than the spring constant of the above-mentioned elastic conductive member.

[0046] By making the spring constant of the conductive plate greater than the spring constant of the elastic conductive member, a gap is formed between the conductive plate and the cover material. This can prevent the deformation of the cover material caused by the pressure from the elastic conductive member or the load on the joint between the concave container and the cover material. In addition, since the cover material and the power generation element are not conductive, the cover material can be made to have no potential.

[0047] [First embodiment]

[0048] The first embodiment of the present disclosure is described in detail below using Figures 1 to 6. First, as shown in Figure 1, the all-solid-state battery 1 is composed of a housing 10, a power generation element 20 housed in the housing 10, an elastic conductive member 30 and a conductive plate 40, and external terminals 13 and 14 disposed on the outer surface of the housing 10.

[0049] The housing 10 includes a concave container 11 and a cover material 12. The concave container 11 is made of ceramic. The concave container 11 includes a quadrangular bottom 111 and a quadrangular cylindrical side wall 112, which is continuously formed from the outer periphery of the bottom 111 and has a cylindrical space for accommodating the power generation element 20 inside. The side wall 112 is arranged to extend substantially perpendicularly relative to the bottom 111 when viewed in longitudinal section. A conductor portion 113 is formed inside the bottom 111. The conductor portion 113 extends between the power generation element 20 and the bottom 111 in a manner of being electrically connected to the power generation element 20, forming a conduction path corresponding to the electrode layer 21. A conductor portion 114 is formed inside the side wall 112. As shown in FIG. 1, a portion of the conductor portion 114 is exposed on the inner peripheral surface of the side wall 112, and on the lower surface and side surface of the support portion 115 described later, forming a conduction path corresponding to the electrode layer 22. The manufacturing method of the concave container 11 will be described later. It should be noted that the material of the concave container 11 is not particularly limited, and various materials such as resin, glass (borosilicate glass, glass ceramic, etc.), metal and ceramic can be exemplified. It can also be a composite material in which ceramic and glass powders are dispersed in resin. In the case where the concave container 11 is composed of a metal material, in order to ensure the insulation between the concave container 11 and the power generation element 20, it is preferred to cover the inner surface of the bottom 111 and the inner circumferential surface of the side wall 112 of the concave container 11 with an insulating material such as a resin material or glass. The concave container 11 is not limited to a quadrilateral shape when viewed from above, and can also be a circular shape, an elliptical shape, and a polygonal shape. The space inside for accommodating the power generation element 20 is not limited to a cylindrical shape, and can also be formed into a polygonal cylindrical shape such as a quadrilateral cylindrical shape according to the shape of the power generation element 20. In addition, the conductor part 114 may not be formed inside the side wall part 112, but may be formed on the inner surface of the side wall part 112, and then pass through the inside of the bottom 111 to be conductive with the external terminal 14. In this case, it is preferable to form an insulating layer between the outer peripheral surface of the power generating element 20 and the conductor portion 114 , for example, on the inner surface of the conductor portion 114 so that the outer peripheral surface of the power generating element 20 and the conductor portion 114 do not contact each other.

[0050] The side wall portion 112 has a plurality of support portions 115 for supporting the conductive plate 40 described later. In the present embodiment, the support portion 115 is an extension portion formed at the upper end portion of the inner circumferential surface of the side wall portion 112 and extending in the circumferential direction of the inner circumferential surface. More specifically, as shown in FIG. 2 , the support portion 115 is a plurality of recessed top walls formed on the inner circumferential surface of the side wall portion 112 toward the radially outer side. Thus, the support portion 115 is formed to extend in the circumferential direction of the inner circumferential surface. The lower surface of each support portion 115, that is, the lower surface of each top wall can lock and support the supported portion 41 of the conductive plate 40 described later. In addition, in the present embodiment, four support portions 115 are provided, but the number is not limited. For example, when the supported portion 41 of the conductive plate 40 is set to two, two support portions 115 can be provided at positions corresponding to the supported portion 41.

[0051] The cover material 12 is a square metal thin plate covering the opening of the concave container 11. As shown in FIG. 1 and FIG. 3, the cover material 12 is joined (seam welded) to the concave container 11 by a square frame-shaped sealing ring 15 disposed between the lower surface of the outer peripheral end and the upper end of the concave container 11. As a result, the internal space of the housing 10 is completely sealed. Considering the influence on the power generation element 20, the internal space of the housing 10 is preferably a vacuum atmosphere or an inert gas atmosphere such as nitrogen. It should be noted that the cover material 12 is not limited to a metal thin plate as long as it can cover the opening of the concave container 11. The cover material 12 is not limited to a square shape, and can be changed to various shapes such as a circular shape, an elliptical shape, and a polygonal shape according to the shape of the concave container 11 when viewed from above. In addition, the cover material 12 can also be a shape other than a flat plate. It should be noted that the cover material 12 can also be bonded to the concave container 11 by an adhesive, and the method of joining the cover material 12 to the concave container 11 is not particularly limited as long as the internal space of the housing 10 can be sealed.

[0052] The external terminal 13 is arranged on the outer surface of the bottom 111 of the concave container 11. The external terminal 13 is electrically connected to the elastic conductive member 30 described later via the conductor portion 113. As described later, the elastic conductive member 30 is electrically connected to the electrode layer 21 that functions as a positive electrode layer. Therefore, the conductor portion 113 serves as a conduction path that connects the external terminal 13 to the positive electrode layer, and the elastic conductive member 30 serves as a connection terminal that connects the conduction path to the electrode layer 21, so that the external terminal 13 functions as a positive electrode terminal.

[0053] The external terminal 14 is arranged on the outer surface of the bottom 111 of the concave container 11 separately from the external terminal 13. The external terminal 14 is electrically connected to the supported portion 41 of the conductive plate 40 described later via the conductor portion 114. As described later, the conductive plate 40 is electrically connected to the electrode layer 22 that functions as a negative electrode layer. Therefore, the conductor portion 114 becomes a conduction path that allows the external terminal 14 to be conductive with the negative electrode layer, and the conductive plate 40 becomes a connection terminal that allows the conduction path to be conductive with the electrode layer 22, so that the external terminal 14 functions as a negative electrode terminal. It should be noted that the arrangement of the external terminal 13 and the external terminal 14 is not limited to the above arrangement, and can also be arranged on the outer surface of the side wall portion 112 of the concave container 11, or the cover material 12 can be made to function as the conductor portion 114, and the external terminal 14 can be formed on the outer surface of the cover material 12. However, by arranging these two terminals on the outer surface of the bottom 111 of the concave container 11 with a certain interval, it is easy to install them on the surface of the circuit board.

[0054] Here, the manufacturing method of the concave container 11 is described. First, a metal paste is printed and applied on a ceramic green sheet to form a printed pattern of the conductor part 113 and the conductor part 114. Then, a plurality of green sheets formed with these printed patterns are stacked and fired. The above-mentioned support part 115 is formed by stacking a plurality of green sheets of different shapes. In this way, a concave container 11 having the conductor part 113 and the conductor part 114 inside and the above-mentioned support part 115 on the inner peripheral surface of the side wall part 112 can be manufactured. It should be noted that as long as the support part 115 can be formed on the inner peripheral surface of the side wall part 112, it is not limited to such a manufacturing method. It should be noted that the external terminal 13 and the external terminal 14 can also be formed by the printed pattern of the metal paste.

[0055] The power generation element 20 includes an electrode stack formed by stacking an electrode layer (positive electrode layer) 21, an electrode layer (negative electrode layer) 22, and a solid electrolyte layer 23. The solid electrolyte layer 23 is arranged between the electrode layer 21 and the electrode layer 22. The power generation element 20 is formed in a cylindrical shape. The power generation element 20 is stacked with an electrode layer 21, a solid electrolyte layer 23, and an electrode layer 22 in sequence from the bottom 111 side of the concave container 11 (the bottom in the figure). That is, the power generation element 20 is configured in a manner that one end, i.e., the electrode layer 21, becomes the bottom 111 side of the concave container 11, and the other end, i.e., the electrode layer 22, becomes the cover material 12 side, and is stored in the internal space of the housing 10. It should be noted that the power generation element 20 is not limited to a cylindrical shape, and can be changed to various shapes such as a rectangular parallelepiped shape and a polygonal column shape. In addition, the power generation element 20 may also have a plurality of stacks. A plurality of stacks may be stacked in a manner connected in series, and the all-solid battery 1 may be a bipolar battery.

[0056] The electrode layer 21 includes an electrode mixture layer (positive electrode mixture layer) 211 and a porous metal layer 212. The electrode mixture layer 211 is composed of a positive electrode mixture containing lithium cobalt oxide as a positive electrode active material, a sulfide-based solid electrolyte, and graphene as a conductive additive in a mass ratio of 65:30:5. The porous metal layer 212 is composed of a sheet-like porous metal substrate. The electrode layer 21 is a positive electrode particle formed into a cylindrical shape by stacking the electrode mixture layer 211 and the porous metal layer 212. At this time, the electrode layer 21 is formed as follows: a portion of the porous metal layer 212 is buried in the electrode mixture layer 211, more specifically, as shown in FIG. 1, it is buried in the surface portion of the electrode mixture layer 211 (the surface portion opposite to the porous metal layer 212). As a result, the active material and the conductive auxiliary agent constituting the electrode mixture layer 211 have more contact points with a part of the porous metal substrate to form a porous metal layer 212, and as a result, the internal resistance of the all-solid-state battery 1 can be reduced. In addition, in the electrode layer 21, in order to reduce the resistance when in contact with the elastic conductive member 30, it is preferred that the surface of the porous metal substrate at the end of the porous metal layer 212 on the opposite side of the electrode mixture layer 211 is exposed. As shown in FIG. 1, the electrode mixture layer 211 is arranged in a manner opposite to the solid electrolyte layer 23. The porous metal layer 212 is arranged on the inner bottom surface side of the bottom 111 of the concave container 11, and is in contact with the plane portion 31 of the elastic conductive member 30. By placing the porous metal layer 212 between the electrode mixture layer 211 and the elastic conductive member 30, when the power generation element 20 is pressed toward the cover material 12 by the elastic conductive member 30 described later, the contact resistance is reduced compared to the case where the surface of the electrode mixture layer 211 is in direct contact with the plane portion 31 of the elastic conductive member 30, and the internal resistance of the all-solid battery 1 is reduced. As a result, the all-solid battery 1 can fully reduce the internal resistance, and can fully absorb the deviation of the thickness of the power generation element 20 or the height of the shell 10, thereby reducing the deviation of the internal resistance value. As a result, the electrical connection reliability of the all-solid battery 1 can be improved. It should be noted that the positive electrode active material of the electrode mixture layer 211 is not particularly limited as long as it can function as the positive electrode layer of the power generation element 20. For example, it can be lithium nickelate, lithium manganate, lithium nickel cobalt manganese composite oxide, olivine-type composite oxide, etc., or a substance appropriately mixed with them. There is no particular limitation on other constituent materials and proportions. The size and shape of the electrode layer 21 are not limited to a cylindrical shape, and may be variously changed according to the size and shape of the all-solid-state battery 1 .

[0057] More specifically, the porous metal layer 212 can preferably use a foamed metal porous body with a high porosity and pores that penetrate from one surface to another surface. In order to easily fill the pores of the porous metal layer 212 with the electrode mixture layer 211 during the process of pressurizing the porous metal layer 212 and the electrode mixture layer 211, and to easily integrate the porous metal layer 212 with the electrode mixture layer 211, the porosity of the porous metal layer 212 before compression is preferably 80% or more, more preferably 90% or more, and particularly preferably 95% or more. On the other hand, in order to ensure good conductivity, the porosity of the porous metal layer 212 before compression is preferably 99.5% or less, more preferably 99% or less, and particularly preferably 98.5% or less. The thickness of the porous metal layer 212 before assembling the all-solid battery 1 is preferably 0.1 mm or more, more preferably 0.3 mm or more, and particularly preferably 0.5 mm or more. On the other hand, it is preferably 3 mm or less, more preferably 2 mm or less, and particularly preferably 1.5 mm or less. In addition, the porous metal layer 212 can preferably use, for example, Sumitomo Electric Industries, Ltd. (Celmet (registered trademark)) or the like. The same is true for the porous metal layer 222 described later.

[0058] The electrode layer 22 includes an electrode mixture layer (negative electrode mixture layer) 221 and a porous metal layer 222. The electrode mixture layer 221 contains LTO (Li4Ti5O) which is a negative electrode active material used in lithium ion secondary batteries at a mass ratio of 50:40:10. 12, lithium titanate), sulfide-based solid electrolyte and graphene negative electrode mixture. The porous metal layer 222 is composed of a sheet-like porous metal substrate. The electrode layer 22 is a negative electrode particle formed into a cylindrical shape in a stacked manner of the electrode mixture layer 221 and the porous metal layer 222. At this time, the electrode layer 22 is formed as follows: a portion of the porous metal layer 222 is buried in the electrode mixture layer 221, more specifically, as shown in FIG1, buried in the surface portion of the electrode mixture layer 221 (the surface portion opposite to the porous metal layer 222). As a result, the active material and the conductive auxiliary agent constituting the electrode mixture layer 221 have more contact points with a portion of the porous metal substrate to form the porous metal layer 222, and as a result, the internal resistance of the all-solid-state battery 1 can be reduced. In addition, in the electrode layer 22, in order to reduce the resistance when in contact with the conductive plate 40, it is preferred that the surface of the porous metal substrate at the end of the porous metal layer 222 on the opposite side of the electrode mixture layer 221 is exposed. As shown in FIG1 , the electrode mixture layer 221 is arranged in a manner opposite to the solid electrolyte layer 23. The porous metal layer 222 is arranged on the side of the cover material 12 and contacts the bottom surface 42 of the conductive plate 40. By placing the porous metal layer 222 between the electrode mixture layer 221 and the conductive plate 40, when the conductive plate 40 stops the movement of the power generation element 20 pressed by the elastic conductive member 30 toward the cover material 12, the contact resistance is reduced compared to the case where the surface of the electrode mixture layer 221 is in direct contact with the conductive plate 40, and the internal resistance of the all-solid battery 1 is reduced. As a result, the all-solid battery 1 can fully reduce the internal resistance, and can fully absorb the deviation of the thickness of the power generation element or the height of the shell, etc., and reduce the deviation of the internal resistance value. As a result, the electrical connection reliability of the all-solid battery 1 can be improved. It should be noted that the negative electrode active material of the electrode mixture layer 221 is not particularly limited as long as it can function as the negative electrode layer of the power generation element 20. For example, in addition to metallic lithium and lithium alloys, it can also be carbon materials such as graphite and low-crystalline carbon, oxides such as SiO, etc., or a material appropriately mixed with them. There are no particular restrictions on other constituent materials and proportions. In addition, the porous metal layer 222 is the same as the above-mentioned porous metal layer 212. The size and shape of the electrode layer 22 are not limited to a cylindrical shape, and various changes can be made according to the size and shape of the all-solid battery 1.

[0059] The solid electrolyte layer 23 includes a sulfide-based solid electrolyte. The solid electrolyte layer 23 is formed into a cylindrical shape. It should be noted that the solid electrolyte contained in the electrode mixture layer 211, the electrode mixture layer 221 and the solid electrolyte layer 23 is not particularly limited. From the perspective of ion conductivity, it is preferred to use a sulfide-based solid electrolyte, especially a sulfide-based solid electrolyte of the argyrodite type. In the case of using a sulfide-based solid electrolyte, in order to prevent reaction with the positive electrode active material, it is preferred to coat the surface of the positive electrode active material with a lithium ion conductive material such as niobium oxide. In addition, the solid electrolyte contained in the solid electrolyte layer 23, the electrode mixture layer 211 and the electrode mixture layer 221 can be a hydride-based solid electrolyte, an oxide-based solid electrolyte, etc. In addition, the size and shape of the solid electrolyte layer 23 are not limited to a cylindrical shape, and various changes can be made according to the size and shape of the all-solid-state battery 1.

[0060] Here, the steps of making the power generation element 20 are described. First, a solid electrolyte powder is placed in a powder molding mold with a diameter of 7.45 mm, and a press machine is used to perform pressure molding at a surface pressure of 70 MPa to form a temporary molded layer of the solid electrolyte layer 23. Furthermore, the above-mentioned negative electrode mixture is placed on the upper surface of the temporary molded layer of the solid electrolyte layer 23, and pressure molding is performed at a surface pressure of 50 MPa to form a temporary molded layer of the negative electrode on the temporary molded layer of the solid electrolyte layer 23. Next, a foamed metal porous body made of a metal such as nickel cut into a diameter of 7.45 mm is placed on the temporary molded layer of the negative electrode formed on the temporary molded layer of the solid electrolyte layer 23, and pressure molding is performed at a surface pressure of 300 MPa to form an integrated body of the solid electrolyte layer 23 and the electrode layer 22. Furthermore, after the mold is turned upside down, the positive electrode mixture is placed on the upper surface of the solid electrolyte layer 23 in the mold (the surface opposite to the surface integrated with the electrode layer 22), and pressure molding is performed at a surface pressure of 50 MPa to form a temporary molded layer of the positive electrode on the solid electrolyte layer 23. Next, a material obtained by cutting a foamed metal porous body made of a metal such as nickel, which is the same material as that used in the negative electrode, is placed on the temporary molded layer of the positive electrode formed on the solid electrolyte layer 23, and pressure molding is performed at a surface pressure of 1400 MPa to obtain a power generation element 20 in which the electrode layer 21, the solid electrolyte layer 23, and the electrode layer 22 are stacked and integrated.

[0061] As shown in FIGS. 1 and 4 , the elastic conductive member 30 is disposed between the power generating element 20 and the bottom 111 of the concave container 11. The elastic conductive member 30 is a metal spring. Thus, compared with the case where a conductive rubber or a carbon sheet is used as the elastic conductive member 30, an electrical connection with low internal resistance can be obtained. More specifically, the elastic conductive member 30 includes a plane portion 31 and four legs 32. The plane portion 31 is circular in a plan view. The plane portion 31 is opposite to the electrode layer 21 and is in contact with the porous metal layer 212. The plane portion 31 uses the elastic force of the elastic conductive member 30 to press the power generating element 20 in the direction of the cover material 12. Therefore, the planar shape of the plane portion 31 is preferably a shape similar to the planar shape of the power generating element 20. In addition, the plane portion 31 is formed in a planar shape so that the power generating element 20 can be pressed in the direction of the cover material 12 with a larger area. In this way, by pressing the power generating element 20 with a larger area by the plane portion 31, the damage of the electrode layer 21 when the power generating element 20 expands can be suppressed. In addition, a larger contact area between the elastic conductive member 30 and the power generating element 20 is ensured, and the elastic conductive member 30 and the power generating element 20 are electrically connected with a larger area, thereby maintaining a good electrical connection. The leg portion 32 extends from the end of the plane portion 31 toward the bottom 111 and toward the radial outside. FIG. 5 is a diagram showing a state in which the power generating element 20 and the elastic conductive member 30 are accommodated in the internal space of the concave container 11. As shown in FIG. 5, first, the elastic conductive member 30 is placed on the inner bottom surface of the bottom 111 of the concave container 11 in a manner that the four legs 32 are in contact with the conductor portion 113, that is, the leg portion 32 faces the inner bottom surface of the bottom 111 of the concave container 11 (toward the bottom in the figure). Thereafter, the power generating element 20 is placed on the upper surface of the plane portion 31 in a manner that the porous metal layer 212 faces downward, and the power generating element 20 is pressed from the top to the bottom. As a result, the four legs 32 expand radially outward, and the power generating element 20 and the plane portion 31 move toward the bottom 111. Thus, the power generating element 20 is pressed upward by the elastic force of the elastic conductive member 30. Then, in order to prevent the power generating element 20 from moving upward, a conductive plate 40 described later is fixed to the side wall 112 of the concave container 11 above the power generating element 20.

[0062] As shown in FIGS. 1 and 6 , the conductive plate 40 is a metal plate having a quadrilateral shape when viewed from above and is provided at the opening of the concave container 11 of the housing 10. The conductive plate 40 has a plurality of supported portions 41 corresponding to the positions of the above-mentioned respective supporting portions 115. In the present embodiment, the supported portion 41 is a hook-shaped locking piece that is locked to the above-mentioned supporting portion 115, i.e., the lower surface of the top wall. More specifically, the supported portion 41 extends from the edge end of the conductive plate 40 toward the above-mentioned supporting portion 115 (toward the bottom of FIG. 1 ). The supported portion 41 has a front end that is folded back toward the supporting portion 115, i.e., the lower surface of the top wall. The front end of the supported portion 41 contacts the conductor portion 114 exposed on the lower surface and side surface of the above-mentioned top wall. Thus, the conductive plate 40 functions as a current collector and functions as a connection terminal that electrically connects the electrode layer 22 and the conduction path connected to the external terminal 14. The conductive plate 40 is supported by a support portion 115 formed on the inner peripheral surface of the concave container 11, and covers a portion of the opening of the concave container 11. The area of ​​the conductive plate 40 is smaller than the opening area of ​​the concave container 11 in a plan view.

[0063] The conductive plate 40 has a recessed portion that is recessed toward the electrode layer 22 at a position that contacts the other end of the power generation element 20, that is, the upper surface of the electrode layer 22. The bottom surface 42 of the recess is formed in a planar shape so that the movement of the power generation element 20 in the direction of the cover material 12 caused by the elastic conductive member 30 can be prevented with a larger area. In addition, the surrounding of the bottom surface 42 of the recess forms a step portion 43 that is displaced in the thickness direction. The step portion 43 is a circumferential wall of a truncated cone whose diameter gradually decreases toward the power generation element 20. As shown in FIG. 1, the bottom surface 42 of the recess is opposite to the electrode layer 22 and contacts the upper surface of the porous metal layer 222 in the electrode layer 22. In this way, the movement of the power generation element 20 is prevented with a larger area by the planar bottom surface 42, and the damage of the electrode layer 22 when the power generation element 20 expands can be suppressed. In addition, by ensuring a larger contact area between the conductive plate 40 and the power generation element 20, the conductive connection between the conductive plate 40 and the power generation element 20 is performed with a larger area, and a good electrical connection can be maintained. In addition, by providing the step portion 43, the overall thickness of the conductive plate 40 can be reduced. Furthermore, the edge end of the conductive plate 40, that is, the position of the supported portion can be freely set in the height direction (thickness direction of the conductive plate), so even if a gap is formed between the cover material 12 and the conductive plate 40, the distance between the cover material 12 and the bottom surface 42 of the conductive plate 40 will not increase. As a result, the gap between the cover material 12 and the power generation element 20 can be suppressed from increasing, so that the capacity of the all-solid-state battery 1 can be increased. It should be noted that the thickness direction refers to the up-down direction of FIG. 1 (the height direction of the all-solid-state battery 1), which can also be said to be a direction orthogonal to the bottom surface 42 in the figure.

[0064] Examples of the metal constituting the elastic conductive member 30 and the conductive plate 40 include nickel, iron, copper, chromium, cobalt, titanium, aluminum and alloys thereof, and preferably, stainless steel for springs such as SUS301-CSP, SUS304-CSP, SUS316-CSP, SUS420 J2-CSP, SUS631-CSP and SUS632 J1-CSP are used because they can easily function as leaf springs.

[0065] In addition, in order to make the pressing force on the power generation element 20 be above a certain level, the thickness of the elastic conductive member 30 and the conductive plate 40 is preferably 0.05 mm or more, more preferably 0.07 mm or more, and particularly preferably 0.1 mm or more. On the other hand, in order to prevent the thickness of the conductive plate 40 from becoming too thick and increasing the storage volume in the housing 10, and to make the conductive plate 40 easily deformable and easily stuck to the side wall portion 112, the thickness of the conductive plate 40 is preferably 0.5 mm or less, more preferably 0.4 mm or less, and particularly preferably 0.3 mm or less.

[0066] In order to reduce the contact resistance, the area of ​​the plane portion 31 of the elastic conductive member 30 and the area of ​​the bottom surface 42 of the conductive plate 40 are preferably 10% or more of the area of ​​the electrode layer 21 and the electrode layer 22 of the power generation element 20 facing each other in a plan view, more preferably 30% or more, particularly preferably 50% or more, and most preferably 60% or more. On the other hand, in order to reduce the gap around the radial direction of the power generation element 20, the area of ​​the plane portion 31 and the bottom surface 42 are preferably 100% or less of the area of ​​the electrode layer 21 and the electrode layer 22 of the power generation element 20 facing each other in a plan view, more preferably 95% or less, particularly preferably 90% or less, and most preferably 85% or less. In addition, the shape of the contact surface of the plane portion 31 that contacts the electrode layer 21 and the bottom surface 42 may not be a completely flat surface, and in order to reduce the contact resistance with the power generation element 20, it may be a surface with projections and depressions such as embossing.

[0067] After the elastic conductive member 30 and the power generating element 20 are stored in the inner space of the concave container 11, the conductive plate 40 is placed on the upper surface of the power generating element 20. When the conductive plate 40 is placed on the upper surface of the power generating element 20, the front end of the supported portion 41 is positioned between the upper surface of the power generating element 20 and the support portion 115, that is, the lower surface of the top wall, in the thickness direction of the power generating element 20 (the vertical direction of FIG. 1). Then, while the supported portion 41 of the conductive plate 40 is pressed toward the bottom 111 of the concave container 11, the supported portion 41 is supported by the support portion 115. More specifically, the front end of the supported portion 41 is locked to the support portion 115, that is, the lower surface of the top wall. Since the supported portion 41 is pressed downward, the conductive plate 40 is bent in the opposite direction to the electrode layer 22 while in contact with the power generating element 20. Thus, the conductive plate 40 can prevent the power generating element 20 from moving due to the elastic force of the elastic conductive member 30. In addition, the conductive plate 40 is in more stable contact with the power generation element 20, and there is no positional displacement due to vibration, etc., and a good electrical connection can be maintained. At this time, by forming the above-mentioned recessed portion, the influence of the deflection on the planar bottom surface 42 is reduced, so that the electrical connection can be maintained more well. In this way, as long as the conductive plate 40 can prevent the power generation element 20 from moving toward the cover material 12 in a state where the edge end is supported on the inner peripheral surface of the side wall portion 112, its structure is not particularly limited. In addition, the concave container 11 has two support portions 115, but the number of support portions 115 can also be more than 3. The supported portion 41 can be formed according to the number of support portions 115. It should be noted that as a method of fixing the edge end (supported portion 41) of the conductive plate 40 to the inner peripheral surface of the side wall portion 112 of the concave container 11, a method of bonding the edge end of the conductive plate 40 to the inner peripheral surface of the side wall portion 112 of the concave container 11 can also be exemplified.

[0068] A gap is formed between the conductive plate 40 and the cover material 12. That is, the conductive plate 40 is not in contact with the cover material 12. Thus, even when the conductive plate 40 is pressed in the direction of the cover material 12 due to a change in the volume of the power generation element 20, deformation of the cover material 12 can be suppressed. In addition, as described above, the cover material 12 and the concave container 11 are welded via the sealing ring 15. By providing a gap between the conductive plate 40 and the cover material 12, the influence of welding heat on the power generation element 20 can be suppressed. In addition, since the conductive plate 40 is not in contact with the cover material 12, when the cover material 12 is joined to the upper end surface of the side wall portion 112 of the concave container 11, there is no need to press the power generation element 20 and the conductive plate 40 with the cover material 12, and the sealing of the housing 10 can be improved.

[0069] Here, Modifications 1 and 2 of the elastic conductive member 30 will be described. It should be noted that, here, description of the same configuration as the above-mentioned elastic conductive member 30 is omitted, and basically only the configuration different from the above-mentioned elastic conductive member 30 will be described.

[0070] (Variant 1)

[0071] As shown in Figures 7 and 8, the elastic conductive component 30 of variant example 1 is a disc spring. The disc spring is made of metal. The disc spring is the peripheral wall of a truncated cone with a gradually decreasing diameter. The disc spring does not have a flat portion 31 as in the above-mentioned embodiment. However, by contacting the upper end of the disc spring with the porous metal layer 212 of the power generation element 20, the all-solid-state battery 1 can fully reduce the internal resistance. In addition, it can fully absorb the deviation of the thickness of the power generation element 20 or the height of the shell 10, thereby reducing the deviation of the internal resistance value. As a result, the electrical connection reliability of the all-solid-state battery 1 can be improved. In addition, even if the volume occupied by the elastic conductive component 30 in the internal space of the shell 10 is reduced, the power generation element 20 can be fully pressed in the direction of the cover material 12. It should be noted that, in Figure 7, the disc spring is configured in a manner such that the small diameter end of the disc spring contacts the porous metal layer 212 and the large diameter end contacts the conductor part 113, but the disc spring may also be configured in a manner such that the large diameter end of the disc spring contacts the porous metal layer 212 and the small diameter end contacts the conductor part 113.

[0072] (Variant 2)

[0073] As shown in FIG9 , the elastic conductive component 30 of variant example 2 is a corrugated washer. The corrugated washer is made of metal. The corrugated washer does not have a planar portion 31 as in the above-mentioned embodiment. However, by contacting a portion of the upper surface of the corrugated washer with the porous metal layer 212 of the power generation element 20, the all-solid-state battery 1 can sufficiently reduce the internal resistance. In addition, it can fully absorb the deviation of the thickness of the power generation element 20 or the height of the shell 10, thereby reducing the deviation of the internal resistance value. Furthermore, the inner bottom surface of the bottom 11 of the power generation element 20 or the concave container 11 is in surface contact with the corrugated washer at multiple locations, so that a good electrical connection can be maintained. In addition, the corrugated washer does not have a sharp front end formed by being interrupted in the middle, so the risk of damaging the power generation element 20 can be reduced. As a result, the electrical connection reliability of the all-solid-state battery 1 can be improved.

[0074] As shown in FIG. 10 , the elastic conductive member 30 of variant 3 is a conical spring. The conical spring is made of metal. The conical spring is in annular contact with the porous metal layer 212 of the power generating element 20. Thus, the same effect as the above-mentioned disc spring can be obtained, and even if the volume occupied by the elastic conductive member 30 in the internal space of the housing 10 is smaller than that of the above-mentioned disc spring, the power generating element 20 can be fully pressed toward the cover material 12, and a good electrical connection can be maintained. It should be noted that even if the elastic conductive member 30 is a conical spring, the conical spring can be configured in a manner that the small diameter end of the conical spring contacts the porous metal layer 212 and the large diameter end contacts the conductor part 113, as in the case of the disc spring, or the conical spring can be configured in a manner that the large diameter end of the conical spring contacts the porous metal layer 212 and the small diameter end contacts the conductor part 113.

[0075] As described above, the elastic conductive member 30 used in the all-solid-state battery 1 may be any metal spring as long as it has conductivity and can press the power-generating element 20 toward the cover member 12 .

[0076] In the above-mentioned embodiment, the conductive plate 40 is arranged between the power generation element 20 and the cover material 12, and the conductive plate 40 is in contact with the porous metal layer 222. However, the conductive plate 40 may not be provided, and a sheet-shaped current collector may be arranged on the lower surface of the cover material 12, and the conductor portion 114 and the electrode layer 22 may be electrically connected via the current collector. Alternatively, the cover material 12 may be used as a current collector, and the cover material 12 may be in contact with the porous metal layer 222. In this case, the power generation element 20 pressed toward the cover material 12 by the elastic conductive member 30 is prevented from moving toward the cover material 12. In this way, the all-solid-state battery 1 may be used as long as the power generation element 20 can be prevented from moving toward the cover material 12 and the electrode layer 22 can be electrically connected to the conductor portion 114 even if the conductive plate 40 is not provided.

[0077] In the above-mentioned embodiment, the electrode layer 21 functions as a positive electrode layer and the electrode layer 22 functions as a negative electrode layer, but the electrode layer 21 may function as a negative electrode layer and the electrode layer 22 may function as a positive electrode layer. In this case, the external terminal 13 functions as a negative electrode terminal and the external terminal 14 functions as a positive electrode terminal.

[0078] [Second embodiment]

[0079] Next, the all-solid-state battery 1 of the second embodiment will be specifically described using Fig. 11. It should be noted that description of the same configurations as those of the first embodiment will be omitted, and basically only configurations different from those of the first embodiment will be described.

[0080] In the all-solid battery 1 of the second embodiment, the porous metal layer 212 and the porous metal layer 222 are not formed on the electrode layer 21 and the electrode layer 22. However, the electrode layer 21 and the electrode layer 22 may also have the porous metal layer 212 and the porous metal layer 222. That is, the all-solid battery 1 of the second embodiment is irrelevant to the presence or absence of the porous metal layer 212 and the porous metal layer 222.

[0081] The conductive plate 40 has a spring constant greater than that of the elastic conductive member 30. Thus, a gap is formed between the conductive plate 40 and the cover material 12. As a result, deformation of the cover material 12 caused by pressure from the elastic conductive member 30 or load on the joint (sealing ring 15) between the concave container 11 and the cover material 12 can be prevented. In addition, since the cover material 12 and the power generation element 20 are not conductive, the cover material 12 can be made to have no potential. It should be noted that, as shown in FIG12 , the spring constant can be determined based on the difference in load and the difference in deflection at two load points. That is, when the load when the deflection of the elastic conductive member 30 is L1 is set to P1 and the load when the deflection is L2 is set to P2, the spring constant is a value represented by the following formula (1).

[0082] Spring constant = load difference / deflection difference = (P2-P1) / (L2-L1) (1)

[0083] It should be noted that the various modifications of the elastic conductive member 30 in the first embodiment can also be applied to the elastic conductive member in the second embodiment.

[0084] As mentioned above, although embodiment was described, this disclosure is not limited to the said embodiment, Various changes are possible as long as they do not deviate from the summary.

[0085] It should be noted that according to the present disclosure, it can contribute to Goal 7 (ensuring access to affordable, reliable, sustainable and modern energy for all) and Goal 12 (ensuring sustainable production and consumption patterns) of the Sustainable Development Goals (SDGs) advocated by the United Nations.

[0086] Explanation of symbols

[0087] 1 All-solid-state battery, 10 casing, 11 concave container, 12 cover material, 13 external terminal, 14 external terminal, 15 sealing ring, 111 bottom, 112 side wall, 113 conductor, 114 conductor, 115 support, 20 power generation element, 30 elastic conductive member, 31 plane, 32 leg, 40 conductive plate, 41 supported portion, 42 bottom surface, 43 step portion.

Claims

1. A fully solid battery comprising: a housing, a power generation element and an elastic conductive member, The housing includes a concave container having a bottom and a side wall, and a cover material covering an opening of the concave container. The power generating element is sealed in the housing and includes a first electrode layer disposed on the bottom side, a second electrode layer disposed on the cover side, and a solid electrolyte layer disposed between the first electrode layer and the second electrode layer. The elastic conductive member is disposed between the power generating element and the inner bottom surface of the bottom of the concave container. The first electrode layer includes a first electrode mixture layer and a first porous metal layer disposed between the first electrode mixture layer and the elastic conductive member, and is electrically connected to a first conductive path extending from the inside to the outside of the housing via the elastic conductive member. The second electrode layer includes a second electrode mixture layer and a second porous metal layer disposed between the second electrode mixture layer and the cover material, and is electrically connected to a second conductive path extending from the inside to the outside of the housing. At least a portion of the first porous metal layer is buried in the surface layer of the first electrode mixture layer and is integrated with the first electrode mixture layer, and an end of the first porous metal layer opposite to the first electrode mixture layer is exposed on the surface of the first electrode layer. At least a portion of the second porous electrode layer is buried in the surface layer of the second electrode mixture layer and is integrated with the second electrode mixture layer, and an end of the second porous metal layer opposite to the second electrode mixture layer is exposed on the surface of the second electrode layer. The elastic conductive member contacts the first porous metal layer and presses the power generating element toward the cover member.

2. The all-solid-state battery according to claim 1, wherein: The elastic conductive member is a metal spring.

3. The all-solid-state battery according to claim 1, wherein: The elastic conductive member includes a flat portion in contact with the first porous metal layer and a leg portion extending toward an inner bottom surface of the bottom of the concave container.

4. The all-solid-state battery according to claim 1, wherein: The elastic conductive member is a disc spring.

5. The all-solid-state battery according to claim 1, wherein: The elastic conductive member is a wave washer.

6. The all-solid-state battery according to claim 1, wherein: The elastic conductive member is a conical spring.

7. The all-solid-state battery according to any one of claims 1 to 6, wherein The all-solid-state battery further comprises a conductive plate between the power generation element and the cover material. The conductive plate prevents the power generating element pressed by the elastic conductive member from moving toward the cover material. The second electrode layer is electrically connected to the second conductive path via the conductive plate. A gap is formed between the conductive plate and the cover material.

8. An all-solid battery comprising: a housing, a power generation element, an elastic conductive member and a conductive plate, The housing includes a concave container having a bottom and a side wall, and a cover material covering an opening of the concave container. The power generating element is sealed in the housing and includes a first electrode layer disposed on the bottom side, a second electrode layer disposed on the cover side, and a solid electrolyte layer disposed between the first electrode layer and the second electrode layer. The elastic conductive member is disposed between the power generating element and the inner bottom surface of the bottom of the concave container. The conductive plate is disposed between the power generating element and the cover material. The first electrode layer is electrically connected to a first conductive path extending from the inside to the outside of the housing via the elastic conductive member. The second electrode layer is electrically connected to a second conductive path extending from the inside to the outside of the housing via the conductive plate. The elastic conductive member contacts the first electrode layer and presses the power generating element toward the cover material. The conductive plate contacts the second electrode layer to prevent the power generation element from moving toward the cover material. The spring constant of the conductive plate is greater than the spring constant of the elastic conductive member.

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