All-solid-state batteries

Abstract

To provide an all-solid-state battery with excellent long-term reliability and electrical connectivity. [Solution] The all-solid-state battery 1 of the present invention comprises a battery container 10 and an electrode stack 20 housed within the battery container 10. The battery container 10 comprises a concave container 11 and a sealing body 12. The opening of the concave container 11 is sealed by the sealing body 12, and the sealing body 12 is provided with electrode terminals 13 that lead to the inside of the concave container 11. The sealing body 12 and the electrode terminals 13 are insulated and airtightly joined by a hermetic seal 14. A current collector 15 is arranged on the surface of the electrode stack 20 on the side of the electrode terminals 13. The electrode terminals 13 and the current collector 15 do not come into direct contact but are electrically connected via lead wires 17. An insulating elastic member 16 is arranged between the current collector 15 and the sealing body 12.

Description

Technical Field

[0001] The present application relates to all-solid-state batteries with excellent long-term reliability and electrical connectivity.

Background Art

[0002] In recent years, instead of organic electrolytes, the development of all-solid-state batteries using solid electrolytes has been actively carried out. Since all-solid-state batteries do not use flammable organic electrolytes, they have high safety. In addition, all-solid-state batteries not only have high safety, but also have high reliability, high environmental resistance, and long life. Therefore, they are expected to contribute to the development of society and at the same time continue to contribute to peace of mind and safety as maintenance-free batteries.

[0003] By the way, in secondary batteries including all-solid-state batteries, flat-shaped ones such as coin-shaped batteries and button-shaped batteries are known. In such flat batteries, a gasket is interposed between the outer can and the sealing can, and an outer body formed by caulking the open end of the outer can inward is used as a battery container. However, in a battery container using such an outer body, it is difficult to prevent the intrusion of moisture from the outside. In particular, in an all-solid-state battery having a solid electrolyte that easily reacts with moisture, there is a problem that the long-term reliability of the battery is reduced due to the intrusion of moisture.

[0004] In order to solve the above problems, Patent Document 1 proposes a hermetic terminal that is welded and sealed to a positive electrode terminal or a negative electrode terminal with a glassy substance, and these are welded and sealed to a metal upper lid, and further a battery container in which a battery case and the upper lid are joined by laser welding. By using such a battery container, it is possible to prevent the intrusion of moisture from the outside into the battery.

[0005] However, in the terminal structure described in Patent Document 1, since the electrode stack and the hermetic terminal are directly connected, if the battery is subjected to shock, vibration, etc., these shocks and vibrations are transmitted to the hermetic terminal, causing damage such as cracks in the glassy material portion of the hermetic terminal, which leads to a problem of reduced long-term reliability and electrical connectivity of the battery.

[0006] Furthermore, in the terminal structure described in Patent Document 1, where the electrode stack and the hermetic terminal are directly connected, it is difficult to absorb the dimensional tolerances during the manufacturing of the electrode stack of the all-solid-state battery, which is made of solid material, resulting in a poor yield.

[0007] Furthermore, all-solid-state batteries typically use an electrode laminate with low flexibility, formed by sandwiching a solid electrolyte molded body between a positive electrode molded body containing a positive electrode active material and a negative electrode molded body containing a negative electrode active material. As a result, the hermetic terminals cannot follow the expansion and contraction of the electrode laminate during charging and discharging, leading to damage to the glassy material portion of the hermetic terminals. [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] Japanese Patent Application Publication No. 8-203482 [Overview of the project] [Problems that the invention aims to solve]

[0009] This invention was made under the circumstances described above, and aims to provide an all-solid-state battery having hermetic terminals that exhibits excellent long-term reliability and electrical connectivity. [Means for solving the problem]

[0010] The all-solid-state battery of the present invention comprises a battery container and a power generation element housed within the battery container, wherein the battery container comprises a concave container and a sealing body, the concave container and the sealing body are made of a metal material, the concave container has a bottom portion and a side wall portion, the opening of the concave container is sealed by the sealing body, the sealing body has electrode terminals that lead to the inside of the concave container, the sealing body and the electrode terminals are insulated and hermetically joined by a hermetic seal, the power generation element comprises an electrode laminate including a positive electrode, a negative electrode and a solid electrolyte layer disposed between the positive electrode and the negative electrode, a current collector is disposed on the electrode terminal side surface of the electrode laminate, the electrode terminals and the current collector are electrically connected via a conductive portion without direct contact, and an insulating elastic member is disposed between the current collector and the sealing body. [Effects of the Invention]

[0011] According to this invention, it is possible to provide an all-solid-state battery with excellent long-term reliability and electrical connectivity. [Brief explanation of the drawing]

[0012] [Figure 1] Figure 1 is a schematic cross-sectional view showing an all-solid-state battery of the first embodiment. [Figure 2] Figure 2 is a schematic cross-sectional view showing an all-solid-state battery of the second embodiment. [Modes for carrying out the invention]

[0013] An embodiment of the all-solid-state battery of the present invention will now be described. The all-solid-state battery of this embodiment includes a battery container and a power generation element housed in the battery container, the battery container includes a concave container and a sealing body, the concave container and the sealing body are made of a metal material, the concave container has a bottom portion and a side wall portion, the opening of the concave container is sealed by the sealing body, the sealing body has electrode terminals that lead to the inside of the concave container, the sealing body and the electrode terminals are insulated and hermetically joined by a hermetic seal, the power generation element consists of an electrode laminate including a positive electrode, a negative electrode and a solid electrolyte layer disposed between the positive electrode and the negative electrode, a current collector is disposed on the electrode terminal side surface of the electrode laminate, the electrode terminals and the current collector are not in direct contact but are electrically connected via a conductive portion, and an insulating elastic member is disposed between the current collector and the sealing body.

[0014] In this embodiment of the all-solid-state battery, an electrode stack including a solid electrolyte layer is used, but since a gasket is not used to seal the battery container, it is possible to prevent moisture from entering the battery container from the outside, thereby suppressing the deterioration of the battery's long-term reliability due to moisture intrusion.

[0015] Furthermore, in this embodiment of the all-solid-state battery, the electrode terminals and the current collector are not in direct contact but are electrically connected via a conductive part, and an insulating elastic member is placed between the current collector and the sealing body. Therefore, even if the battery is subjected to shock or vibration, the shock or vibration is absorbed by the insulating elastic member, and the propagation of the shock or vibration is blocked between the electrode terminals and the current collector. As a result, the shock or vibration is not directly transmitted to the hermetic seal, preventing damage such as cracks from occurring in the hermetic seal. This improves the long-term reliability and electrical connectivity of the battery.

[0016] In addition, in the all-solid-state battery of the present embodiment, since an insulating elastic member is disposed between the current collector member and the sealing body, the current collector member can be pressed against the electrode laminate by the pressing force of the insulating elastic member. Even if the electrode laminate itself does not have flexibility, and even if the electrode laminate repeatedly expands and contracts with discharge, good electrical contact between the electrode laminate and the current collector member can be achieved, and the electrical connectivity between the electrode laminate and the current collector member can be improved.

[0017] In addition, in the all-solid-state battery of the present embodiment, since an insulating elastic member is disposed between the current collector member and the sealing body, dimensional tolerances during the manufacture of the electrode laminate of the all-solid-state battery formed of a solid can be absorbed, and the production efficiency of the battery can be improved.

[0018] In addition, since the pressing force of the insulating elastic member also acts between the electrode laminate and the bottom surface portion of the concave container, good electrical contact between the electrode laminate and the concave container can be achieved, and the electrical connectivity between the electrode laminate and the concave container can be improved. Thereby, the electrical connectivity in the entire battery can be improved.

[0019] Hereinafter, the all-solid-state battery of the present embodiment will be described based on the drawings.

[0020] (First Embodiment) First, the all-solid-state battery of the first embodiment will be described based on FIG. 1. FIG. 1 is a cross-sectional view schematically showing the all-solid-state battery of the first embodiment. In FIG. 1, the all-solid-state battery 1 includes a battery container 10 and an electrode laminate 20 composed of a power generation element housed in the battery container 10. The battery container 10 includes a concave container 11 and a sealing body 12. The concave container 11 includes a bottom surface portion 11a and a side wall portion 11b, and the opening of the concave container 11 is sealed by the sealing body 12. Further, the sealing body 12 includes an electrode terminal 13 that communicates with the inside of the concave container 11, and the sealing body 12 and the electrode terminal 13 are insulated by a hermetic seal 14 and joined airtightly. The electrode laminate 20 includes a positive electrode 21, a negative electrode 22, and a solid electrolyte layer 23 disposed between the positive electrode 21 and the negative electrode 22.

[0021] On the surface of the electrode laminate 20 on the side of the electrode terminal 13, a current collector member 15 is arranged. The electrode terminal 13 and the current collector member 15 are not in direct contact, but are electrically connected via a lead wire 17 that constitutes a conductive portion. Also, an insulating elastic member 16 is arranged between the current collector member 15 and the sealing body 12. The insulating elastic member 16 has a through hole 16a in its central portion, and the lead wire 17 is arranged inside the through hole 16a. Further, the current collector member 15 is pressed against the electrode laminate 20 by the pressing force of the insulating elastic member 16.

[0022] In the all-solid-state battery of this embodiment, there is a space portion 18 between the insulating elastic member 16 and the side wall portion 11b of the concave container 11. Thereby, even if the thickness of the electrode laminate changes due to charge and discharge, the increase in the thickness of the electrode laminate can be absorbed by the contraction in the thickness direction and the expansion in the outer peripheral direction of the insulating elastic member 16.

[0023] Also, the insulating elastic member 16 covers the lower part A of the interface between the electrode terminal 13 and the hermetic seal 14. Further, the insulating elastic member 16 covers the lower part B of the interface between the hermetic seal 14 and the sealing body 12. Thereby, the airtightness at the interface between the electrode terminal 13 and the hermetic seal 14 and at the interface between the hermetic seal 14 and the sealing body 12 can be improved.

[0024] The concave container 11 is made of a metal material such as stainless steel, nickel, or iron. The concave container 11 includes a circular bottom surface portion 11a and a cylindrical side wall portion 11b that is continuously formed from the outer periphery of the bottom surface portion 11a and has a space for accommodating the electrode laminate 20 inside. The side wall portion 11b is provided so as to extend substantially perpendicular to the bottom surface portion 11a in a longitudinal cross-sectional view. Also, the concave container 11 is not limited to a circular shape in a plan view, and may be a square shape, an elliptical shape, or a polygonal shape.

[0025] The sealing body 12 is a circular metal plate that covers the opening of the concave container 11. The sealing body 12 is made of a metal material such as stainless steel, nickel, or iron. As shown in Figure 1, the sealing body 12 is joined to the concave container 11 by laser welding or the like between the lower surface of its outer peripheral end and the upper end of the side wall portion 11b of the concave container 11. As a result, the opening of the concave container 11 is sealed by the sealing body 12, and the internal space of the battery container 10 is completely sealed. The internal space of the battery container 10 is preferably a vacuum atmosphere or an inert gas atmosphere such as nitrogen, considering the effect on the electrode stack 20, which is a power generation element. The sealing body 12 is not limited to a circular shape and can be changed to various shapes such as a square shape, an ellipse shape, and a polygonal shape depending on the shape of the concave container 11 in plan view.

[0026] The electrode terminals 13 are made of metal materials such as stainless steel, nickel, or iron. The hermetic seal 14 can be made of glassy materials such as borosilicate glass or sodabarium glass. The hermetic seal 14 offers excellent airtightness, as well as superior insulation, voltage resistance, pressure resistance, and environmental resistance.

[0027] In this embodiment, the battery container 10 does not use a gasket for its sealing, the sealing body 12 and the concave container 11 are joined by welding, and the electrode terminals 13 and the sealing body 12 are joined by a hermetic seal 14. Therefore, moisture can be prevented from entering the battery container 10 from the outside, and the deterioration of the battery's long-term reliability due to moisture intrusion can be suppressed.

[0028] The electrode terminal 13 is positioned in the center of the sealing body 12 via a hermetic seal 14. The electrode terminal 13 is electrically connected to the negative electrode 22 via a lead wire 17 and a current collector 15. Therefore, the lead wire 17 and the current collector 15 form a conductive path that connects the electrode terminal 13 and the negative electrode 22, and the electrode terminal 13 functions as the negative electrode terminal.

[0029] The concave container 11 is directly electrically connected to the positive electrode 21. Therefore, the concave container 11 functions as a positive electrode terminal.

[0030] In this embodiment, the electrode stack 20 may be housed in the internal space of the battery container 10 with its orientation reversed. In this case, the electrode terminals 13 function as positive electrode terminals, and the concave container 11 functions as negative electrode terminals.

[0031] The electrode stack 20, which consists of power generation elements, is formed by stacking a positive electrode 21, which is made of a molded body of a positive electrode mixture containing a positive electrode active material, a negative electrode 22, which is made of a molded body of a negative electrode mixture containing a negative electrode active material, and a solid electrolyte layer 23. The solid electrolyte layer 23 is positioned between the positive electrode 21 and the negative electrode 22. The electrode stack 20 is formed in a cylindrical shape. The electrode stack 20 is stacked in the order of positive electrode 21, solid electrolyte layer 23, and negative electrode 22 from the bottom surface 11a side of the concave container 11. The electrode stack 20 is not limited to a cylindrical shape and can be modified in various ways to match the shape of the concave container 11. In addition, the electrode stack 20 may have multiple electrode stacks. In this case, the multiple electrode stacks are stacked so as to be connected in series.

[0032] The positive electrode active material used in the positive electrode 21 is not particularly limited in type as long as it functions as a positive electrode component of the power generation element. For example, materials used in the positive electrodes of lithium-ion secondary batteries, such as lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium nickel cobalt manganese composite oxide, and olivine-type composite oxide, can be used, and these may be mixed as appropriate. For example, a positive electrode molded body (pellet) formed into a cylindrical shape from a positive electrode mixture containing LCO (LiCoO2, lithium cobalt oxide), a sulfide-based solid electrolyte, and carbon black as a conductive additive can be used as the positive electrode.

[0033] The negative electrode active material used in the negative electrode 22 is not particularly limited in type as long as it functions as a negative electrode component of the power generation element. For example, materials used in the negative electrode of lithium-ion secondary batteries can be used, such as lithium titanate; metallic lithium, lithium alloys; carbon materials such as graphite and low-crystallinity carbon; oxides such as SiO, and these can be mixed as appropriate. For example, LTO(Li4Ti5O 12A negative electrode can be used as a negative electrode if it is formed into a cylindrical shape from a negative electrode mixture containing lithium titanate, a sulfide-based solid electrolyte, and carbon black as a conductive additive.

[0034] The solid electrolyte layer 23 can be used as a molded body (pellet) formed by shaping the solid electrolyte into a cylindrical form. The type of solid electrolyte used in the solid electrolyte layer 23 is not particularly limited; for example, hydride-based solid electrolytes, sulfide-based solid electrolytes, oxide-based solid electrolytes, etc., can be used. However, from the viewpoint of ionic conductivity, sulfide-based solid electrolytes, particularly argyrodite-type sulfide-based solid electrolytes, are preferred. When using a sulfide-based solid electrolyte, it is preferable to coat the surface of the positive electrode active material with a lithium-ion conductive material such as niobium oxide to prevent reaction with the positive electrode active material. Furthermore, the solid electrolytes contained in the positive electrode 21 and negative electrode 22 are not particularly limited and may also be hydride-based solid electrolytes or oxide-based solid electrolytes.

[0035] The current collector 15 is a circular conductor that covers the upper surface of the electrode stack 20. The current collector 15 is pressed against the negative electrode 22 of the electrode stack 20 by an insulating elastic member 16, and the current collector 15 is electrically connected to the lead wire 17. As a result, the current collector 15 functions as a current collector and also forms part of the conductive path that electrically connects the negative electrode 22 and the electrode terminal 13. The current collector 15 covers the entire upper surface of the electrode stack 20, but it does not necessarily have to cover the entire surface, and there may be parts of the upper surface of the electrode stack 20 that are not covered by the current collector 15. The shape of the current collector 15 is not limited to a circle in plan view, but may be a square or polygon.

[0036] The current collector 15 can be made of a porous carbon sheet, a porous metal sheet, a metal foil, etc., but among porous carbon sheets and porous metal sheets, those that can be compressed by pressing force are particularly preferred. When a porous carbon sheet or porous metal sheet that can be compressed by pressing force is used for the current collector 15, the current collector 15 is pressed and compressed against the electrode laminate 20 by the pressing force of the insulating elastic member 16. As a result, even if the electrode laminate 20 itself is not flexible, the current collector 15 itself can be flexibly deformed by pressing force, and even if there are some irregularities on the surface of the electrode laminate 20, the current collector 15 can absorb these irregularities, so that the electrical contact between the electrode laminate 20 and the current collector 15 is good and the electrical connectivity between the electrode laminate 20 and the current collector 15 can be improved.

[0037] Examples of porous carbon sheets that can be compressed by the above pressing force include carbon felt; woven or nonwoven carbon fiber fabrics; porous carbon fiber sheets such as woven or nonwoven carbon nanotube fiber fabrics; and porous graphite sheets made from molded expanded graphite. The fiber diameter of the carbon fibers used in the porous carbon fiber sheet is preferably 1 nm to 1 μm. The basis weight of the porous carbon fiber sheet is 5 to 200 g / m². 2 It is preferable that this is the case. Furthermore, the thickness of the carbon fiber porous sheet after compression is not particularly limited, but can be set to, for example, 0.05 to 1 mm.

[0038] The type of porous metal sheet that can be compressed by the above pressing force is not particularly limited, but for example, foamed metal sheets, metal powder sintered sheets, and metal fiber sintered sheets can be used. Examples of metals that can be used for porous metal sheets include Ni, Al, Cu, Ni-Cr alloys, Ni-Sn alloys, and stainless steel alloys. The porosity of the porous metal sheet before compression is not particularly limited as long as its compressibility is maintained, but for example, it can be set to 50-98%. The thickness of the porous metal sheet after compression is also not particularly limited, but for example, it can be set to 0.05-1 mm.

[0039] The type of metal foil used is not particularly limited, but for example, foils made of Ni, Al, Cu, Ni-Cr alloy, Ni-Sn alloy, stainless steel alloy, etc., can be used. The thickness of the metal foil is also not particularly limited, but can be set to, for example, 0.05 to 1 mm.

[0040] In this embodiment, a lead wire 17 is used as the conductive part connecting the electrode terminal 13 and the current collector 15, but other materials such as coil springs, leaf springs, and metal plates can also be used. The material of the conductive part is not particularly limited as long as it is a metal, and for example, Ni, Al, Cu, Ni-Cr alloy, Ni-Sn alloy, and stainless steel alloy can be used. Furthermore, the lead wire and coil spring are joined to the electrode terminal 13 and the current collector 15 by welding or other means, respectively.

[0041] Furthermore, the conductive portion can also be formed from a conductive resin. The type of conductive resin is not particularly limited, but for example, a resin that has been imparted conductivity by dispersing metal powder or carbon powder in an insulating resin, or a resin that is conductive itself, such as a conductive polymer, can be used.

[0042] The insulating elastic member 16 is a circular sheet material in plan view, positioned between the current collector 15 and the inner bottom surface of the sealing body 12. It has the function of being compressed when a pressing force is applied in the thickness direction and being able to fully restore its shape when the pressing force is removed. The insulating elastic member 16 also has a through hole 16a in its center for arranging the lead wire 17 (conductive part). By setting the initial thickness of the insulating elastic member 16 to be greater than the distance between the current collector 15 and the inner bottom surface of the sealing body 12, when the insulating elastic member 16 is positioned between the current collector 15 and the inner bottom surface of the sealing body 12 and the concave container 11 and the sealing body 12 are joined, the insulating elastic member 16 is compressed as it is pushed inward by the sealing body 12 towards the battery container 10. Due to its elastic force, the insulating elastic member 16 presses the current collector 15 against the electrode stack 20 and also presses the electrode stack 20 toward the bottom surface 11a of the concave container 11. This allows the electrode stack 20, the current collector 15, and the concave container 11 to maintain good electrical connection.

[0043] Furthermore, as described above, the insulating elastic member 16 is compressed when a pressing force is applied in the thickness direction and can fully restore its shape when the pressing force is removed. Therefore, even if the electrode laminate 20 repeatedly expands and contracts with charging and discharging, the insulating elastic member 16 can maintain the pressing force applied to the electrode laminate 20 by repeatedly compressing and restoring in response to the expansion and contraction of the electrode laminate 20. The shape of the insulating elastic member 16 is not limited to a circular shape in plan view, but may be an ellipse, or a polygon such as a square, pentagon, hexagon, or octagon.

[0044] Furthermore, although the insulating elastic member 16 does not cover the entire surface of the current collector member 15 in Figure 1, it can also be positioned to cover the entire surface. By covering the entire surface, the insulating elastic member 16 can press against the current collector member 15 over a wider area, and by ensuring reliable electrical connection between the electrode laminate 20 and the current collector member 16 over a wider area, the electrical connectivity between the electrode laminate 20 and the current collector member 15 can be further improved.

[0045] The type of insulating elastic member 16 is not particularly limited, but for example, rubber sheets such as silicone rubber sheets, silicone sponge rubber sheets, butyl rubber sheets, and fluororesin rubber sheets can be used. The thickness of the insulating elastic member 16 after compression is not particularly limited, but can be set to, for example, 0.05 to 1 mm. Also, the thickness of the insulating elastic member 16 before compression is not particularly limited, but it should be set to be 0.01 to 2 mm larger than the thickness after compression.

[0046] (Second Embodiment) Next, the all-solid-state battery of the second embodiment will be described with reference to Figure 2. Figure 2 is a schematic cross-sectional view showing the all-solid-state battery of the second embodiment. The all-solid-state battery 2 of this embodiment shown in Figure 2 has the same configuration as the all-solid-state battery 1 of the first embodiment, except that porous metal substrates 21b and 22b are further arranged on the outer surfaces of both the positive and negative electrodes of the electrode stack 20 of the all-solid-state battery 1 of the first embodiment shown in Figure 1. Therefore, in the all-solid-state battery 2 of this embodiment, the explanation of the same configuration as the all-solid-state battery 1 of the first embodiment will be basically omitted, and only the configuration that differs from the all-solid-state battery 1 of the first embodiment will be described.

[0047] In this embodiment, the all-solid-state battery 2 houses an electrode stack 20 consisting of power generation elements within the internal space of a battery container 10. As shown in Figure 2, the electrode stack 20 is formed by stacking a positive electrode 21, which is made of a positive electrode mixture layer 21a consisting of a molded positive electrode mixture containing a positive electrode active material and a porous metal substrate 21b embedded in the surface layer of the positive electrode mixture layer 21a; a negative electrode 22, which is made of a negative electrode mixture layer 22a consisting of a molded negative electrode mixture containing a negative electrode active material and a porous metal substrate 22b embedded in the surface layer of the negative electrode mixture layer 22a; and a solid electrolyte layer 23. The end faces of the porous metal substrates 21b and 22b are exposed on the outer surfaces of the positive electrode 21 and negative electrode 22, respectively.

[0048] By embedding porous metal substrates 21b and 22b on the outer surface of the electrode stack 20 and exposing at least the end faces of the porous metal substrates 21b and 22b on the outer surface of the electrodes, the contact resistance of the outer surface of the electrode stack 20 can be reduced between the electrode stack 20 and the current collector 15 and between the electrode stack 20 and the concave container 11, thereby achieving better electrical connection and further improving electrical connectivity. The porous metal substrates may be embedded on the outer surface of either the positive electrode or the negative electrode.

[0049] The porous metal substrates 21b and 22b are not particularly limited in type, as long as they can be embedded on the surface of the electrode. For example, foamed metal substrates, metal powder sintered substrates, metal fiber sintered substrates, etc., can be used. Examples of metals that can be used for the porous metal substrates include Ni, Al, Cu, Ni-Cr alloys, Ni-Sn alloys, and stainless steel alloys. The porosity of the porous metal substrate is not particularly limited, but can be set to, for example, 50-98%. The thickness of the porous metal substrate after embedding is also not particularly limited, but can be set to, for example, about 0.5-60% of the thickness of the electrode mixture layer.

[0050] The method for manufacturing an electrode with a porous metal substrate embedded on its outer surface is not particularly limited, but for example, it can be manufactured by a first step of pouring an electrode mixture into a mold and press-molding it, a second step of placing a sheet-like porous metal substrate on the electrode mixture press-molded in the first step, and a third step of pressurizing the electrode mixture and the porous metal substrate, further compressing the electrode mixture to form an electrode mixture layer while embedding the porous metal substrate into the electrode mixture from the electrode mixture side surface, and compressing the porous metal substrate in the thickness direction to integrate the electrode mixture layer and the porous metal substrate.

[0051] Although embodiments of the all-solid-state battery of the present invention have been described above, the present invention is not limited to the above embodiments, and various modifications are possible as long as they do not depart from the spirit of the invention. [Examples]

[0052] A battery was fabricated using a silicone rubber sheet as an insulating elastic material, with the electrode terminals and current collector connected via lead wires. When this battery was subjected to vibration testing using a vibration testing machine, no damage to the hermetic seal was observed.

[0053] A battery was fabricated using a silicone rubber sheet as an insulating elastic material, with the electrode terminals directly connected to the current collector. When this battery was subjected to vibration testing using a vibration testing machine, the glass portion of the hermetic seal broke.

[0054] A battery was fabricated in which the electrode terminals and current collector were connected via lead wires, without using any insulating elastic material. When this battery was subjected to vibration testing using a vibration testing machine, the glass portion of the hermetic seal broke.

[0055] With respect to the embodiments of the present invention described above, the following additional forms are further disclosed. (Appendix form 1) A solid-state battery comprising a battery container and a power generation element housed within the battery container, The battery container includes a concave container and a sealing body. The concave container and the sealing body are made of a metal material. The aforementioned concave container comprises a bottom portion and a side wall portion, The opening of the concave container is sealed with the sealing body. The sealing body is equipped with electrode terminals that lead to the inside of the concave container, The sealing body and the electrode terminals are insulated and hermetically joined by a hermetic seal. The power generation element comprises an electrode laminate including a positive electrode, a negative electrode, and a solid electrolyte layer disposed between the positive electrode and the negative electrode. A current collector is placed on the electrode terminal side surface of the electrode laminate. The electrode terminal and the current collector are not in direct contact, but are electrically connected via a conductive part. An all-solid-state battery characterized in that an insulating elastic member is disposed between the current collector and the sealing body. (Appendix Form 2) The all-solid-state battery according to Appendix Form 1, wherein the conductive part is selected from lead wires, coil springs, leaf springs, and metal plates. (Appendix form 3) The all-solid-state battery according to appendix form 1, wherein the conductive part is formed of a conductive resin. (Appendix form 4) The all-solid-state battery according to any of appendix forms 1 to 3, wherein the insulating elastic member has a through hole in its central part. (Appendix form 5) An all-solid-state battery according to any of appendix forms 1 to 4, having a space between the insulating elastic member and the side wall portion of the concave container. (Appendix form 6) The all-solid-state battery according to any of appendix forms 1 to 5, wherein the insulating elastic member covers the lower part of the interface between the electrode terminal and the hermetic seal. (Appendix form 7) The all-solid-state battery according to any of the appendix forms 1 to 6, wherein the insulating elastic member covers the lower part of the interface between the hermetic seal and the sealing body. (Appendix form 8) An all-solid-state battery according to any of appendix forms 1 to 7, wherein the insulating elastic member is a rubber sheet. (Appendix form 9) An all-solid-state battery according to any of appendix forms 1 to 8, wherein the sealing body and the concave container are joined by welding. (Appendix form 10) An all-solid-state battery according to any one of appendix forms 1 to 9, wherein the current collecting member is composed of at least one selected from a porous carbon sheet, a porous metal sheet, and a metal foil. (Appendix 11) A porous metal substrate is placed on the outer surface of at least one of the positive electrode and the negative electrode, At least a portion of the porous metal substrate is embedded in the surface layer of the electrode, The all-solid-state battery according to any of the appended embodiments 1 to 10, wherein at least the outer surface of the porous metal substrate is exposed to the outer surface of the electrode. (Appendix 12) The all-solid-state battery according to appendix 11, wherein the porous metal substrate is a foamed metal substrate. [Explanation of Symbols]

[0056] 1, 2 All-solid-state battery 10 Battery container 11 Concave container 12 Sealing body 13 Electrode terminal 14 Hermetic seals 15 Current collector 16 Insulating elastic member 16a Through hole 17 Lead wires 18 Space section 20 Electrode Stack 21 Positive electrode 21a Cathode mixture layer 21b Porous metal substrate 22 Negative electrode 22a Negative electrode mixture layer 22b Porous metal substrate 23 Solid electrolyte layer

Claims

1. A solid-state battery comprising a battery container and a power generation element housed within the battery container, The battery container includes a concave container and a sealing body. The concave container and the sealing body are made of a metal material. The aforementioned concave container comprises a bottom portion and a side wall portion, The opening of the concave container is sealed with the sealing body. The sealing body is equipped with electrode terminals that lead to the inside of the concave container, The sealing body and the electrode terminals are insulated and hermetically joined by a hermetic seal. The power generation element comprises an electrode laminate including a positive electrode, a negative electrode, and a solid electrolyte layer disposed between the positive electrode and the negative electrode. A current collector is placed on the electrode terminal side surface of the electrode laminate. The electrode terminal and the current collector are not in direct contact, but are electrically connected via a conductive part. An all-solid-state battery characterized in that an insulating elastic member is disposed between the current collector and the sealing body.

2. The all-solid-state battery according to claim 1, wherein the conductive part is selected from one of a lead wire, a coil spring, a leaf spring, and a metal plate.

3. The all-solid-state battery according to claim 1, wherein the conductive portion is formed of a conductive resin.

4. The all-solid-state battery according to claim 1, wherein the insulating elastic member has a through hole in its central part.

5. The all-solid-state battery according to claim 1, wherein a space is provided between the insulating elastic member and the side wall portion of the concave container.

6. The all-solid-state battery according to claim 1, wherein the insulating elastic member covers the lower part of the interface between the electrode terminal and the hermetic seal.

7. The all-solid-state battery according to claim 1, wherein the insulating elastic member covers the lower part of the interface between the hermetic seal and the sealing body.

8. The all-solid-state battery according to any one of claims 1 to 7, wherein the insulating elastic member is a rubber sheet.

9. The all-solid-state battery according to claim 1, wherein the sealing body and the concave container are joined by welding.

10. The all-solid-state battery according to claim 1, wherein the current collecting member is composed of at least one selected from a porous carbon sheet, a porous metal sheet, and a metal foil.

11. A porous metal substrate is placed on the outer surface of at least one of the electrodes, the positive electrode and the negative electrode. At least a portion of the porous metal substrate is embedded in the surface layer of the electrode, The all-solid-state battery according to claim 1, wherein at least the outer surface of the porous metal substrate is exposed to the outer surface of the electrode.

12. The all-solid-state battery according to claim 11, wherein the porous metal substrate is a foamed metal substrate.

Images