All-solid-state battery

Abstract

To provide an all-solid-state battery, in which a negative electrode current collector extension portion that connects a negative electrode current collector to a negative electrode tab is less likely to short-circuit with a positive electrode current collector.SOLUTION: An all-solid-state battery includes a positive electrode, a negative electrode, and a solid electrolyte layer laminated between the positive electrode and the negative electrode. The positive electrode includes a positive electrode current collector and a positive electrode active material layer formed on a surface of the positive electrode current collector, and the positive electrode current collector includes a positive electrode current collector extension portion connected to a positive electrode tab. The negative electrode includes a negative electrode current collector, and the negative electrode current collector includes a negative electrode current collector extension portion connected to a negative electrode tab. At least an end portion of the solid electrolyte layer on a side of the negative electrode current collector extension portion includes an expansion portion expanding to a position beyond an outer periphery of the positive electrode active material layer. The expansion portion includes an insulating base material, an insulating frame is provided around the outer periphery of the positive electrode active material layer, the expansion portion expands to a position beyond an outer periphery of the insulating frame, and at least part of the expansion portion is supported by the insulating frame.SELECTED DRAWING: Figure 4A

Description

[Technical Field]

[0001] The present invention relates to an all-solid-state battery. [Background technology]

[0002] In recent years, research and development into secondary batteries, which contribute to energy efficiency, has been conducted to ensure that more people have access to affordable, reliable, sustainable, and advanced energy. Among secondary batteries, all-solid-state batteries with a stacked structure in which a positive electrode current collector, a positive electrode layer, a solid electrolyte layer, a negative electrode layer, and a negative electrode current collector are stacked in this order have attracted particular attention due to their superior safety (the non-flammable solid electrolyte) and higher energy density. Known all-solid-state batteries with this stacked structure have a configuration in which the positive electrode current collector and the positive electrode tab are connected by an extension of the positive electrode current collector, and the negative electrode current collector and the negative electrode tab are connected by an extension of the negative electrode current collector. For all-solid-state batteries with this structure, the placement of an insulating frame around the outer periphery of the positive electrode active material layer has been considered to prevent short-circuiting between the positive and negative electrodes within the battery (Patent Document 1). Furthermore, the placement of a porous body between the positive and negative electrodes, which has an electrolyte region supported by a solid electrolyte and an unsupported region without a solid electrolyte, has also been considered (Patent Document 2). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2023-47083 [Patent Document 2] International Publication No. 2024 / 013532 Summary of the Invention [Problem to be solved by the invention]

[0004] Increasing capacity and preventing short circuits between the positive and negative electrodes are key challenges for secondary batteries. All-solid-state lithium batteries have been investigated as high-capacity batteries. These batteries use lithium ions as a charge transfer medium, depositing lithium from the positive electrode layer onto the negative electrode layer during charging and absorbing it into the positive electrode layer during discharging. The thickness of the negative electrode layer in all-solid-state lithium batteries changes with charging and discharging. Therefore, in all-solid-state lithium batteries, the positive and negative electrode current collector extensions are preferably deformable in response to changes in the thickness of the negative electrode layer. However, deformation of the negative electrode current collector extension in response to changes in the thickness of the negative electrode layer can lead to a short circuit between the negative electrode current collector extension and the positive electrode current collector. Furthermore, if the negative electrode current collector extension and the positive electrode current collector are positioned close to each other due to manufacturing variations, external vibrations can cause a short circuit between the negative electrode current collector extension and the positive electrode current collector.

[0005] The present invention has been made in view of the above circumstances, and has an object to provide an all-solid-state battery in which a short circuit is less likely to occur between an extension portion of a negative electrode current collector that connects the negative electrode current collector and a negative electrode tab and the positive electrode current collector. [Means for solving the problem]

[0006] The present inventors have found that the above-mentioned problems can be solved by providing an extension portion at the end of the solid electrolyte layer on the negative electrode current collector extension side, the extension portion extending beyond the outer periphery of the positive electrode active material layer, and including an insulating substrate in the extension portion, and have thus completed the present invention.

[0007] (1) An all-solid-state battery comprising: a positive electrode, a negative electrode, and a solid electrolyte layer laminated between the positive electrode and the negative electrode; the positive electrode comprises a positive electrode current collector and a positive electrode active material layer formed on a surface of the positive electrode current collector, the positive electrode current collector having a positive electrode current collector extension connected to a positive electrode tab; the negative electrode comprises a negative electrode current collector, and the negative electrode current collector has a negative electrode current collector extension connected to a negative electrode tab; at least an end of the solid electrolyte layer on the side of the negative electrode current collector extension has an extended portion that extends to a position beyond the outer periphery of the positive electrode active material layer, the extended portion including an insulating substrate; and an insulating frame on the outer periphery of the positive electrode active material layer, the extended portion extending to a position beyond the outer periphery of the insulating frame, and at least a portion of the extended portion being supported by the insulating frame.

[0008] According to the all-solid-state battery (1), the end of the solid electrolyte layer facing the negative electrode current collector extension has an extension extending beyond the outer periphery of the positive electrode active material layer. This extension includes an insulating substrate, resulting in high shape stability. Therefore, even if the thickness of the negative electrode changes due to charge and discharge, the negative electrode current collector extension and the positive electrode current collector are less likely to short-circuit. Furthermore, there is no particular need to interpose an insulating substrate between the positive electrode active material layer of the positive electrode of the solid electrolyte layer and the negative electrode facing each other. The absence of an insulating substrate facilitates the conduction of the charge transfer medium (lithium ions) compared to when an insulating substrate is interposed. Furthermore, because an insulating frame is disposed around the outer periphery of the positive electrode active material layer, even if the positive electrode current collector extension deforms toward the negative electrode current collector, the positive electrode current collector extension and the negative electrode current collector are less likely to short-circuit. Furthermore, because at least a portion of the extension is supported by the insulating frame, the shape stability of the extension is further enhanced.

[0009] (2) The all-solid-state battery according to (1), wherein the length of the portion of the extension portion that extends beyond the outer periphery of the insulating frame is longer than the total thickness of the positive electrode active material layer and the positive electrode current collector.

[0010] In the all-solid-state battery (2), the length of the portion of the extension that extends beyond the outer periphery of the insulating frame is the above-mentioned length, so that the negative electrode current collector extension and the positive electrode current collector are less likely to short-circuit.

[0011] (3) The all-solid-state battery according to (1) or (2), wherein at least a portion of the extension portion that extends beyond the outer periphery of the insulating frame is formed of the insulating base material alone.

[0012] (3) In the all-solid-state battery, the solid electrolyte layer in the extension section is less likely to chip.

[0013] (4) The all-solid-state battery according to any one of (1) to (3), wherein the extension section has a mixed section in which the insulating substrate is supported by the solid electrolyte layer, and a section in which the insulating substrate is a single substance.

[0014] According to the all-solid-state battery of (4), the insulating substrate is supported by the solid electrolyte layer in the mixed portion, so that the shape of the single portion of the insulating substrate is stable.

[0015] (5) The all-solid-state battery according to any one of (1) to (4), wherein the insulating substrate is a nonwoven fabric.

[0016] In the all-solid-state battery (5), the nonwoven fabric has a rough surface and a high affinity with the material that forms the solid electrolyte layer, which improves the strength of the expansion section.

[0017] (6) An all-solid-state battery comprising: a positive electrode, a negative electrode, and a solid electrolyte layer laminated between the positive electrode and the negative electrode, wherein the positive electrode includes a positive electrode current collector and a positive electrode active material layer formed on a surface of the positive electrode current collector, the positive electrode current collector having a positive electrode current collector extension connected to a positive electrode tab, the negative electrode includes a negative electrode current collector, and the negative electrode current collector has a negative electrode current collector extension connected to a negative electrode tab, at least an end of the solid electrolyte layer on the side of the negative electrode current collector extension has an extension that extends to a position beyond the outer periphery of the positive electrode active material layer, and includes an insulating substrate, a part of the insulating substrate is supported by the solid electrolyte layer, and the remainder is a single part of the insulating substrate.

[0018] According to the all-solid-state battery (6), the insulating substrate included in the extended portion extending beyond the outer periphery of the positive electrode active material layer is partially supported by the solid electrolyte layer, with the remaining portion being an independent portion of the insulating substrate. Therefore, the solid electrolyte layer is less likely to be chipped, and the shape of the independent portion of the insulating substrate is stable. Therefore, even if the thickness of the negative electrode changes due to charging and discharging, a short circuit between the negative electrode current collector extension and the positive electrode current collector is less likely to occur. Furthermore, there is no particular need to interpose an insulating substrate between the portions of the solid electrolyte layer that contact the positive and negative electrodes. By not interposing an insulating substrate, the charge transfer medium (lithium ions) is more easily conducted than when an insulating substrate is interposed. [Effects of the Invention]

[0019] The present invention has been made in view of the above circumstances, and can provide an all-solid-state battery in which an extension portion of a negative electrode current collector and a positive electrode current collector are less likely to short-circuit. [Brief explanation of the drawings]

[0020] [Figure 1] 1 is a plan view showing an all-solid-state battery according to a first embodiment of the present invention. [Figure 2] FIG. 2 is a cross-sectional view taken along line II-II in FIG. [Figure 3] FIG. 3 is a cross-sectional view taken along line III-III in FIG. [Figure 4A] FIG. 3 is an enlarged view of a main part of FIG. 2. [Figure 4B] FIG. 4B is a plan view of the solid electrolyte layer shown in FIG. 4A. [Figure 5A] FIG. 4 is an enlarged cross-sectional view of a main part of an all-solid-state battery according to a second embodiment of the present invention. [Figure 5B] FIG. 5B is a plan view of the solid electrolyte layer shown in FIG. 5A. [Figure 6A] FIG. 10 is an enlarged cross-sectional view of a main part of an all-solid-state battery according to a third embodiment of the present invention. [Figure 6B] FIG. 6B is a plan view of the solid electrolyte layer shown in FIG. 6A. DETAILED DESCRIPTION OF THE INVENTION

[0021] Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the embodiments described below are merely examples of the present invention, and the present invention is not limited to the following.

[0022] [First embodiment] Fig. 1 is a plan view showing an all-solid-state battery according to a first embodiment of the present invention, Fig. 2 is a cross-sectional view taken along line II-II in Fig. 1, Fig. 3 is a cross-sectional view taken along line III-III in Fig. 1, Fig. 4A is an enlarged view of a main part of Fig. 2, and Fig. 4B is a plan view of the solid electrolyte layer shown in Fig. 4A.

[0023] As shown in FIGS. 1 to 4B, the all-solid-state battery 100 includes a positive electrode 10, a negative electrode 20, and a solid electrolyte layer 30 laminated between the positive electrode 10 and the negative electrode 20. The negative electrode 20 and the solid electrolyte layer 30 are laminated so as to sandwich one positive electrode 10. An intermediate layer 40 is disposed between the negative electrode 20 and the solid electrolyte layer 30.

[0024] The positive electrode 10 includes a positive electrode current collector 11 and positive electrode active material layers 12 formed on both surfaces of the positive electrode current collector 11. The positive electrode current collector 11 has a positive electrode current collector extension 11a connected to a positive electrode tab 15. The positive electrode current collector extension 11a does not have the positive electrode active material layer 12 formed thereon. An insulating frame 13 is disposed around the outer periphery of the positive electrode active material layer 12. The end of the insulating frame 13b on the negative electrode current collector extension 21a side is the same as the end of the positive electrode current collector 11. The insulating frame 13a on the positive electrode current collector extension 11a side is wider than the insulating frame 13b on the negative electrode current collector extension 21a side. The width of the insulating frame 13a on the positive electrode current collector extension 11a side may be greater than the total thickness of the positive electrode active material layer 12, the solid electrolyte layer 30, the intermediate layer 40, and the negative electrode 20, for example. If the width of the insulating frame 13a is greater than the total thickness, even if the positive electrode current collector extension 11a is deformed, a short circuit is less likely to occur between the positive electrode current collector extension 11a and the negative electrode 20. The width of the insulating frame 13a may be equal to or less than twice the total thickness.

[0025] The negative electrode 20 includes a negative electrode current collector 21 and a metal layer 22 laminated on the solid electrolyte layer 30 side of the negative electrode current collector 21. The negative electrode current collector 21 has a negative electrode current collector extension 21a connected to a negative electrode tab 25. The metal layer 22 is not laminated on the negative electrode current collector extension 21a. The end of the negative electrode current collector 21 on the positive electrode current collector extension 11a side is located in a position that does not extend beyond the insulating frame 13a on the positive electrode current collector extension 11a side. Therefore, the end of the negative electrode current collector 21 on the positive electrode current collector extension 11a side is less likely to short-circuit with the positive electrode current collector extension 11a.

[0026] The solid electrolyte layer 30 has extensions 30a and 30b that extend beyond the outer periphery of the positive electrode active material layer 12. The extension 30a on the positive electrode current collector extension 11a side is located beyond the end of the negative electrode current collector 21 on the positive electrode current collector extension 11a side. The extension 30b on the negative electrode current collector extension 21a side is located beyond the outer periphery of the insulating frame 13b on the negative electrode current collector extension 21a side. An inner portion 30b1 of the extension 30b, which is located inside the outer periphery of the insulating frame 13b, is supported by the insulating frame 13b on the negative electrode current collector extension 21a side. An outer portion 30b2 of the extension 30b, which extends beyond the outer periphery of the insulating frame 13b, protects the positive electrode current collector 11 to prevent a short circuit between the negative electrode current collector extension 21a and the positive electrode current collector 11 when the negative electrode current collector extension 21a deforms toward the positive electrode 10. The length of the outer portion 30b2 may be longer than the total thickness of the positive electrode active material layer 12 and the positive electrode current collector 11. When the length of the outer portion 30b2 is longer than the total thickness, a short circuit between the negative electrode current collector extension 21a and the positive electrode current collector 11 is less likely to occur. The length of the outer portion 30b2 may be two times or less the total thickness.

[0027] The portion of the solid electrolyte layer 30 that contacts the positive electrode 10 is formed of a solid electrolyte composition 31. In this embodiment, the extension 30a on the positive electrode current collector extension 11a side is also formed of the solid electrolyte composition 31. The extension 30b on the negative electrode current collector extension 21a side includes an insulating base material 32. The insulating base material 32 is embedded in the solid electrolyte composition 31. The inclusion of the insulating base material 32 in the extension 30b improves the shape stability of the extension 30b, and deformation of the negative electrode current collector extension 21a toward the positive electrode current collector 11 of the positive electrode 10 can be suppressed.

[0028] Examples of materials for the positive electrode current collector 11, the positive electrode active material layer 12, the positive electrode tab 15, the negative electrode current collector 21, the metal layer 22, the negative electrode tab 25, the solid electrolyte composition 31, the insulating substrate 32, and the intermediate layer 40 will be described below, taking as an example the case where the all-solid-state battery 100 is an all-solid-state lithium battery that uses lithium ions as a charge transfer medium.

[0029] There are no particular limitations on the material or shape of the positive electrode current collector 11, as long as it has the function of collecting current from the positive electrode 10. Examples of materials for the positive electrode current collector 11 include aluminum, aluminum alloys, stainless steel, nickel, iron, and titanium, and among these, aluminum, aluminum alloys, and stainless steel are preferred. Examples of the shape of the positive electrode current collector 11 include foil and plate shapes.

[0030] The positive electrode active material layer 12 contains at least one type of positive electrode active material. There are no particular limitations on the positive electrode active material, and any material that is used in the positive electrode layers of general solid-state secondary batteries can be used. For example, a layered active material containing lithium, a spinel-type active material, an olivine-type active material, etc. can be used. Specific examples of the positive electrode active material include lithium cobalt oxide (LiCoO2), lithium nickel oxide (LiNiO2), and LiNi p Mn q Co r O2(p+q+r=1), LiNi p Al q CorO2 (p+q+r=1), lithium manganese oxide (LiMn2O4), Li 1+x Mn 2-x-y Examples include heteroelement-substituted Li-Mn spinel represented by MO4 (x+y=2, M=at least one selected from Al, Mg, Co, Fe, Ni, and Zn), lithium titanate (oxide containing Li and Ti), and lithium metal phosphate (LiMPO4, M=at least one selected from Fe, Mn, Co, and Ni).

[0031] The positive electrode active material layer 12 may optionally contain a solid electrolyte from the viewpoint of improving lithium ion conductivity. It may also optionally contain a conductive additive to improve conductivity. Furthermore, it may also optionally contain a binder from the viewpoint of exhibiting flexibility, etc. There are no particular limitations on the solid electrolyte, conductive additive, and binder, and those used in the positive electrode layer of a general all-solid-state lithium battery may be used.

[0032] The material of the positive electrode tab 15 may be the same as or different from the material of the positive electrode current collector 11. The positive electrode tab 15 may be integrally connected to the positive electrode current collector 11.

[0033] The material and shape of the negative electrode current collector 21 are not particularly limited as long as it has the function of collecting current from the negative electrode 20. Examples of materials for the negative electrode current collector 21 include nickel, copper, and stainless steel. Examples of the shape of the negative electrode current collector 21 include a foil shape, a plate shape, and the like.

[0034] The metal layer 22 is not particularly limited in material or shape as long as it has the function of densely depositing lithium ions. A metallic lithium layer or a layer of a metal that forms an alloy with lithium can be used as the metal layer 22. Examples of metals that form an alloy with lithium include Mg, Si, Au, Ag, In, Ge, Sn, Pb, Al, and Zn. The metal that forms the metal layer 22 may be in the form of a powder or a thin film. By using the negative electrode 20 having this metal layer 22, a uniform lithium deposit layer can be formed on the surface of the metal layer 22.

[0035] The material of the negative electrode tab 25 may be the same as the material of the negative electrode current collector 21 or may be different from the material of the negative electrode current collector 21.

[0036] The solid electrolyte composition 31 includes a solid electrolyte. The solid electrolyte is not particularly limited as long as it has lithium ion conductivity, and examples thereof include sulfide solid electrolytes, oxide solid electrolytes, nitride solid electrolytes, and halide solid electrolytes. Examples of sulfide solid electrolytes include Li2S-P2S5 and Li2S-P2S5-LiI. The sulfide solid electrolyte may have an argyrodite-type crystal structure. Examples of oxide solid electrolytes include NASICON-type oxides, garnet-type oxides, and perovskite-type oxides. Examples of NASICON-type oxides include oxides containing Li, Al, Ti, P, and O (e.g., Li 1.5 Al 0.5 Ti 1.5 Examples of garnet-type oxides include oxides containing Li, La, Zr, and O (e.g., LiLaZrO 12 Examples of perovskite oxides include oxides containing Li, La, Ti, and O (for example, LiLaTiO3).

[0037] The solid electrolyte composition 31 may contain a binder. There are no particular restrictions on the binder, and any binder that is used in the solid electrolyte layer of a general solid secondary battery can be used.

[0038] The insulating substrate 32 may be a sheet or a porous body. The insulating substrate 32 may be made of an organic or inorganic material. Examples of organic materials include a resin sheet, woven fabric, and nonwoven fabric. Examples of inorganic materials include a ceramic sheet. Nonwoven fabric has a highly irregular surface and has a high affinity with the solid electrolyte composition 31, thereby improving the strength of the extension portion 30b.

[0039] The intermediate layer 40 may be, for example, a layer that improves the uniformity of lithium ions deposited on the metal layer 22 of the negative electrode 20. The intermediate layer 40 may be a layer that has electronic conductivity and has voids through which lithium ions can pass. The intermediate layer 40 may contain a material that has lithium metal conductivity and a material that has electronic conductivity. As the material that has lithium metal conductivity, for example, amorphous carbon particles can be used. Examples of amorphous carbon particles include carbon blacks such as acetylene black, furnace black, and ketjen black, coke, activated carbon, CNTs (carbon nanotubes), fullerenes, and graphene. As the material that has electronic conductivity, for example, a metal can be used. The metal may be in the form of particles. Examples of metals include Ag, Au, Pt, Pd, Si, Al, Bi, Sn, Zn, Ga, and In.

[0040] The all-solid-state battery 100 of this embodiment configured as described above has an extension portion 30b at the end of the solid electrolyte layer 30 on the negative electrode current collector extension portion 21a side, which extends beyond the outer periphery of the positive electrode active material layer 12. The extension portion 30b includes an insulating substrate 32, providing high shape stability. Therefore, even if the thickness of the negative electrode 20 changes due to charge and discharge, the negative electrode current collector extension portion 21a and the positive electrode current collector 11 are less likely to short-circuit. Furthermore, there is no particular need to interpose an insulating substrate between the solid electrolyte layer 30 and the negative electrode 20, where the positive electrode active material layer 12 of the positive electrode 10 faces the negative electrode 20. The absence of an insulating substrate would inhibit the conduction of the charge transfer medium (lithium ions). Therefore, the absence of an insulating substrate facilitates the conduction of the charge transfer medium compared to the presence of an insulating substrate. Therefore, it is preferable not to interpose an insulating substrate between the positive electrode active material layer 12 and the negative electrode 20 facing each other. Furthermore, since the insulating frame 13 is disposed on the outer periphery of the positive electrode active material layer 12, the positive electrode current collector extension 11a is less likely to deform toward the negative electrode current collector 21 and short-circuit with the negative electrode current collector 21. Furthermore, since the inner portion 30b1 of the extension 30b is supported by the insulating frame 13b, the shape stability of the extension 30a is further improved.

[0041] [Second embodiment] FIG. 5A is an enlarged cross-sectional view of a main part of an all-solid-state battery according to a second embodiment of the present invention, and FIG. 5B is a plan view of the solid electrolyte layer shown in FIG. 5A.

[0042] As shown in Fig. 5A, the all-solid-state battery 100A of this embodiment differs from the all-solid-state battery 100 of the first embodiment in the configuration of the insulating frame 13. Furthermore, as shown in Figs. 5A and 5B, the all-solid-state battery 100A differs from the all-solid-state battery 100 of the first embodiment in the configuration of the solid electrolyte layer 30. Other than these configurations, the all-solid-state battery 100A is the same as the all-solid-state battery 100 of the first embodiment, and therefore the same reference numerals are used and the description thereof will be omitted.

[0043] In the all-solid-state battery 100A of this embodiment, the width of the insulating frame 13a on the positive electrode current collector extension 11a side is the same as the width of the insulating frame 13b on the negative electrode current collector extension 21a side. The extension 30a of the solid electrolyte layer 30 on the positive electrode current collector extension 11a side extends to a position beyond the outer periphery of the insulating frame 13a on the positive electrode current collector extension 11a side. The extension 30a on the positive electrode current collector extension 11a side includes an insulating base material 32. The insulating base material 32 is embedded in the solid electrolyte composition 31. The length of the outer portion of the extension 30a that extends beyond the outer periphery of the insulating frame 13a may be longer than, for example, the total thickness of the intermediate layer 40 and the negative electrode 20. If the length of the outer portion of the extension 30a is longer than the total thickness, the positive electrode current collector extension 11a and the negative electrode 20 are less likely to short-circuit even if the positive electrode current collector extension 11a is deformed. The length of the outer portion of the extension 30a may be up to twice the total thickness.

[0044] The extension 30a on the positive electrode current collector extension 11a side includes an insulating base material 32. The insulating base material 32 is embedded in the solid electrolyte composition 31. The inclusion of the insulating base material 32 in the extension 30a improves the shape stability of the extension 30a, and deformation of the negative electrode current collector extension 21a toward the negative electrode 20 can be suppressed.

[0045] The all-solid-state battery 100A of this embodiment configured as described above has the extension portion 30b including the insulating base material 32, and therefore, similar to the all-solid-state battery 100 of the first embodiment, even if the thickness of the anode 20 changes due to charge and discharge, the anode current collector extension portion 21a and the cathode current collector 11 are less likely to short-circuit. Furthermore, the all-solid-state battery 100A of this embodiment has the same width as the insulating frame 13b, so the battery size can be reduced.

[0046] [Third embodiment] FIG. 6A is an enlarged cross-sectional view of a main part of an all-solid-state battery according to a second embodiment of the present invention, and FIG. 6B is a plan view of the solid electrolyte layer shown in FIG. 6A.

[0047] 6A and 6B, the all-solid-state battery 100B differs from the all-solid-state battery 100 according to the first embodiment in the shape of the extension portion 30b on the negative electrode current collector extension portion 21a side of the solid electrolyte layer 30. Other than this configuration, the all-solid-state battery 100B has the same configuration as the all-solid-state battery 100 according to the first embodiment, and therefore the same reference numerals are used and the description thereof will be omitted.

[0048] In this embodiment, an inner portion 30b1 of the extension portion 30b on the negative electrode current collector extension 21a side is a mixed portion in which the insulating base material 32 is embedded in the solid electrolyte composition 31 and is supported by the solid electrolyte layer 30. An outer portion 30b2 of the extension portion 30b is a portion in which the insulating base material 32 is a single unit.

[0049] The all-solid-state battery 100B of this embodiment configured as described above has an extension portion 30b including the insulating substrate 32. Therefore, similar to the all-solid-state battery 100 of the first embodiment, even if the thickness of the anode 20 changes due to charge and discharge, the anode current collector extension portion 21a and the cathode current collector 11 are less likely to short-circuit. Furthermore, the all-solid-state battery 100B of this embodiment has the same width as the insulating frame 13b, allowing for a smaller battery size. The outer portion 30b2 of the extension portion 30b is a single portion of the insulating substrate 32, making it less likely for the solid electrolyte layer of the solid electrolyte to chip. Furthermore, the inner portion 30b1 of the extension portion 30b is a mixed portion in which the insulating substrate 32 is supported by the solid electrolyte layer 30, thereby stabilizing the shape of the single portion of the insulating substrate.

[0050] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments. For example, in all of the all-solid-state batteries 100, 100A, and 100B of the embodiments, the insulating frame 13 is disposed on the outer periphery of the positive electrode active material layer 12, but the insulating frame 13 may be omitted. [Explanation of symbols]

[0051] 10 positive electrode 11 Positive electrode current collector 11a Positive electrode current collector extension 12 Cathode active material layer 13 Insulating frame 15 Positive electrode tab 20 negative electrode 21 Negative electrode current collector 21a Negative electrode current collector extension 22 Metal layer 25 Negative electrode tab 30 Solid electrolyte layer 30a, 30b extensions 31 Solid electrolyte composition 32 Insulating substrate 40 Middle Class 100, 100A, 100B solid state battery

Claims

1. a positive electrode, a negative electrode, and a solid electrolyte layer laminated between the positive electrode and the negative electrode; the positive electrode includes a positive electrode current collector and a positive electrode active material layer formed on a surface of the positive electrode current collector, the positive electrode current collector having a positive electrode current collector extension connected to a positive electrode tab; the negative electrode includes a negative electrode current collector having a negative electrode current collector extension connected to a negative electrode tab; at least an end of the solid electrolyte layer on the side of the negative electrode current collector extension has an extension portion that extends to a position beyond the outer periphery of the positive electrode active material layer, the extension portion includes an insulating substrate; an insulating frame is provided on the outer periphery of the positive electrode active material layer; The extension portion extends to a position beyond the outer periphery of the insulating frame, At least a portion of the extension portion is supported by the insulating frame.

2. 2. The all-solid-state battery according to claim 1, wherein a length of a portion of the extension portion extending beyond an outer periphery of the insulating frame is longer than a total thickness of the positive electrode active material layer and the positive electrode current collector.

3. 3. The all-solid-state battery according to claim 1, wherein at least a portion of the extension portion extending beyond an outer periphery of the insulating frame is formed by a single piece of the insulating base material.

4. 3. The all-solid-state battery according to claim 1, wherein the extension section has a mixed section in which the insulating substrate is supported by the solid electrolyte layer, and a section in which the insulating substrate is a single substance.

5. The all-solid-state battery according to claim 1 or 2, wherein the insulating substrate is a nonwoven fabric.

6. a positive electrode, a negative electrode, and a solid electrolyte layer laminated between the positive electrode and the negative electrode; the positive electrode includes a positive electrode current collector and a positive electrode active material layer formed on a surface of the positive electrode current collector, the positive electrode current collector having a positive electrode current collector extension connected to a positive electrode tab; the negative electrode includes a negative electrode current collector having a negative electrode current collector extension connected to a negative electrode tab; at least an end of the solid electrolyte layer on the side of the negative electrode current collector extension has an extension portion that extends to a position beyond the outer periphery of the positive electrode active material layer, the extension section includes an insulating substrate, and has a mixed section in which the insulating substrate is supported by the solid electrolyte layer, and a section in which the insulating substrate is a single body.

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