Solid-state battery and method for manufacturing solid-state battery

Abstract

A solid-state battery in which the occurrence of a short circuit is suppressed is provided.SOLUTION: The solid-state battery of the present disclosure includes an electrode body and a current collecting tab connected to the electrode body. The electrode assembly includes a positive electrode current collector, a positive electrode active material layer, a solid electrolyte layer, a negative electrode active material layer, and a negative electrode current collector. The solid electrolyte layer has a support including a plurality of pores. The support has a protruding portion protruding from an end surface of each of the positive electrode active material layer and the negative electrode active material layer.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to solid-state batteries and methods for manufacturing solid-state batteries. [Background technology]

[0002] Solid-state batteries are known as lithium-ion secondary batteries that are excellent in safety.

[0003] Patent Document 1 discloses an all-solid-state battery (hereinafter also referred to as a "solid-state battery"). The solid-state battery includes an electrode body and a current collecting tab connected to the electrode body. The electrode body includes a first current collector, a first active material layer, a solid electrolyte layer, a second active material layer, and a second current collector. The electrode body includes a first side surface portion, a second side surface portion facing the first side surface portion, and a third side surface portion connecting the first side surface portion and the second side surface portion. In the first side surface portion, the first active material layer, the solid electrolyte layer, and the second active material layer are flush with each other. A protective member is disposed on the first side surface portion. The protective member covers the side surface of at least one of the first active material layer, the solid electrolyte layer, and the second active material layer. In the third side surface portion, the first active material layer, the solid electrolyte layer, and the second active material layer are flush with each other. A specific fastening member is disposed on the third side surface portion. The binding member covers the side surfaces of at least one of the first active material layer, the solid electrolyte layer, and the second active material layer. Resin is disclosed as the material for the protection member and the binding member. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2024-11688 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the solid-state battery disclosed in Patent Document 1, the materials of the protective member and the fastening member are different from the material of the electrode assembly. In other words, the thermal expansion coefficients of the protective member and the fastening member are different from the thermal expansion coefficient of the electrode assembly. Therefore, repeated charging and discharging may reduce the adhesive strength of the protective member and the fastening member to the electrode assembly. If at least one of the protective member and the fastening member peels off from the electrode assembly, a short circuit may occur between the positive and negative electrodes of the electrode assembly.

[0006] The present disclosure has been made in consideration of the above circumstances. An object of one embodiment of the present disclosure is to provide a solid-state battery in which the occurrence of short circuits is suppressed, and a method for manufacturing the solid-state battery. [Means for solving the problem]

[0007] The means for solving the above problems include the following embodiments.

[0008] <1> The solid-state battery of the first embodiment comprises: An electrode body and a current collecting tab connected to the electrode body, the electrode body has a positive electrode current collector, a positive electrode active material layer, a solid electrolyte layer, a negative electrode active material layer, and a negative electrode current collector, which are stacked along a stacking direction; the solid electrolyte layer has a support including a plurality of pores; the support has protruding portions protruding from the end faces of the positive electrode active material layer and the negative electrode active material layer, and non-protruding portions that are not the protruding portions, In the solid-state battery, the number of pores in the support in the protruding portions is smaller than the number of pores in the support in the non-protruding portions.

[0009] The term "solid electrolyte layer" refers to a layer that contains a solid electrolyte but does not contain an active material (i.e., at least one of a positive electrode active material and a negative electrode active material). The term "positive electrode active material layer" refers to a layer that contains a positive electrode active material. The term "negative electrode active material layer" refers to a layer that contains a negative electrode active material. The term "support" refers to an insulator that has multiple pores, provides mechanical strength to the solid electrolyte layer, and does not conduct electricity. The term "pores in the support" refers to holes in which a solid electrolyte is disposed and holds the solid electrolyte. The term "protruding portion" includes a protruding portion without a pore obtained by melting a protruding portion with a pore. The protruding portion contains the support and does not contain a solid electrolyte. The term "protruding portion does not contain a solid electrolyte" refers to the ratio of the volume of the solid electrolyte disposed in the protruding portion to the volume of the protruding portion being 10% or less, and may be 0%. The layer structure of the "electrode body" includes a monopolar structure or a bipolar structure.

[0010] In a first embodiment, the support has the protruding portion. The protruding portion prevents electrical contact between the positive electrode active material layer and the negative electrode active material layer. As a result, the occurrence of a short circuit is suppressed in the solid state battery of the first embodiment.

[0011] <2> The solid-state battery of the second embodiment is the electrode body includes a plurality of unit electrode bodies stacked along the stacking direction, the unit electrode body includes the positive electrode current collector, the positive electrode active material layer, the solid electrolyte layer, the negative electrode active material layer, and the negative electrode current collector, Between two adjacent unit electrode bodies, the protruding portions of the adjacent solid electrolyte layers are connected to each other. <1> The solid-state battery is described in

[0012] The laminated structure of the "unit electrode body" includes a monopolar structure and a bipolar structure.

[0013] In the second embodiment, the protruding portions of the adjacent solid electrolyte layers are connected to each other between two adjacent unit electrode bodies. That is, at least one of the positive electrode active material layer and the negative electrode active material layer disposed between the adjacent solid electrolyte layers between the two adjacent unit electrode bodies is likely to be reliably covered by the protruding portions. This more reliably prevents electrical contact between the positive electrode active material layer and the negative electrode active material layer. In addition, the protruding portions more reliably prevent electrical contact between at least one of the positive electrode active material layer and the negative electrode active material layer and the exterior body of the solid battery. As a result, the occurrence of short circuits is more suppressed in the solid battery of the second embodiment.

[0014] <3> The solid-state battery of the third embodiment comprises: the unit electrode body is formed by stacking the positive electrode current collector, the positive electrode active material layer, the solid electrolyte layer, the negative electrode active material layer, the negative electrode current collector, the negative electrode active material layer, the solid electrolyte layer, the positive electrode active material layer, and the positive electrode current collector in this order along the stacking direction, the protruding portions are arranged in the unit electrode body so as to connect the adjacent solid electrolyte layers to each other; <2> The solid-state battery is described in

[0015] In a third aspect, the stacked structure of the electrode assembly is a structure in which a plurality of unit electrode assemblies having a monopolar structure are connected in parallel. In the third aspect, the protruding portions of adjacent solid electrolyte layers in the unit electrode assembly are connected to each other. That is, in the unit electrode assembly, the positive electrode active material layer or the negative electrode active material layer disposed between adjacent solid electrolyte layers is likely to be reliably covered by the protruding portions. This more reliably prevents electrical contact between the positive electrode active material layer and the negative electrode active material layer. In addition, the protruding portions more reliably prevent electrical contact between at least one of the positive electrode active material layer and the negative electrode active material layer and the exterior body of the solid battery. As a result, the occurrence of short circuits is more suppressed in the solid battery of the third aspect.

[0016] <4> The solid-state battery of the fourth aspect is the protruding portion is disposed to cover at least one end surface of the positive electrode active material layer and the negative electrode active material layer; <1> ~ <3> The solid-state battery according to any one of the above items.

[0017] This allows the protruding portion to more reliably prevent electrical contact between the positive electrode active material layer and the negative electrode active material layer. The protruding portion also more reliably prevents electrical contact between at least one of the positive electrode active material layer and the negative electrode active material layer and the exterior body of the solid-state battery. As a result, the occurrence of short circuits is further suppressed in the solid-state battery of the fourth aspect.

[0018] <5> The solid-state battery of the fifth aspect is The electrode body A first side portion; a second side surface portion facing the first side surface portion; a third side surface portion connecting the first side surface portion and the second side surface portion; a fourth side surface portion connecting the first side surface portion and the second side surface portion and facing the third side surface portion; and the current collecting tab protrudes from at least one of the third side surface portion and the fourth side surface portion, the protruding portion is disposed to cover the first side surface portion and the second side surface portion; <1> ~ <4> The solid-state battery according to any one of the above items.

[0019] The "side surface of the electrode body" refers to a surface of the electrode body whose normal direction intersects with the normal direction (stacking direction) of the main surface of the electrode body. The "main surface" refers to a surface whose normal direction is parallel to the stacking direction. The "side surface of the electrode body" includes the end face of the positive electrode active material layer, the end face of the non-protruding portion of the solid electrolyte layer, and the end face of the negative electrode active material layer, but does not include the protruding portion of the solid electrolyte layer. The "non-protruding portion of the solid electrolyte layer" refers to a portion of the solid electrolyte layer that is not a protruding portion. The side surface of the electrode body may include at least one of the end face of the positive electrode current collector and the end face of the negative electrode current collector.

[0020] In the fifth aspect, the protruding portion is arranged to cover the first side surface portion and the second side surface portion. This allows the protruding portion to more reliably prevent electrical contact between the positive electrode active material layer and the negative electrode active material layer than when the protruding portion is not arranged to cover the first side surface portion and the second side surface portion. The protruding portion more reliably prevents electrical contact between at least one of the positive electrode active material layer and the negative electrode active material layer and the exterior body of the solid-state battery. As a result, the occurrence of a short circuit is further suppressed in the solid-state battery of the fifth aspect.

[0021] <6> The solid-state battery of the sixth aspect is The electrode body A first side portion; a second side surface portion facing the first side surface portion; a third side surface portion connecting the first side surface portion and the second side surface portion; a fourth side surface portion connecting the first side surface portion and the second side surface portion and facing the third side surface portion; and the current collecting tab protrudes from at least one of the third side surface portion and the fourth side surface portion, the protruding portions are arranged on the third side surface portion and the fourth side surface portion so as to be connected to the current collecting tabs; <1> ~ <5> The solid-state battery according to any one of the above items.

[0022] "The protruding portions are arranged to connect to the current collecting tabs on the third side surface portion and the fourth side surface portion" means that the protruding portions are in contact with the current collecting tabs. For example, if the protruding portions have pores, the protruding portions may be in physical contact with the current collecting tabs. For example, if the protruding portions do not have pores, the protruding portions may be attached to the current collecting tabs by melting the protruding portions.

[0023] In the sixth aspect, the protruding portions are arranged so as to connect to the current collecting tabs on the third side surface portion and the fourth side surface portion. That is, the positive electrode active material layer or the negative electrode active material layer arranged between the solid electrolyte layer and the current collecting tab is likely to be reliably covered by the protruding portions. As a result, the protruding portions more reliably prevent electrical contact between the positive electrode active material layer and the negative electrode active material layer. The protruding portions more reliably prevent electrical contact between at least one of the positive electrode active material layer and the negative electrode active material layer and the exterior body of the solid battery. As a result, the solid battery of the sixth aspect is more reliably prevented from short-circuiting.

[0024] <7> The seventh aspect of the solid-state battery is The support of the non-protruding portion is made of a nonwoven fabric. <1> ~ <6> The solid state battery according to any one of the above items.

[0025] "Nonwoven fabric" refers to a sheet-like material in which fibers are bonded or intertwined without being woven, and refers to a flat fiber assembly that has a predetermined level of structural strength obtained by physical and / or chemical methods other than weaving, knitting, and papermaking (JIS L0222:2022). The fiber assembly has multiple pores. The nonwoven fabric contains a resin.

[0026] The solid state battery of the seventh embodiment has more sufficient battery performance than a battery in which the support of the non-protruding portions is not made of nonwoven fabric.

[0027] <8> The method for producing a solid-state battery according to an eighth embodiment includes the steps of: preparing a solid electrolyte sheet including a support including a plurality of pores and a solid electrolyte that is not disposed in a protruding portion that indicates a peripheral portion of the support and that is disposed in a portion of the support that is surrounded by the protruding portion; stacking a first current collector, a first active material layer, the solid electrolyte sheet, a second active material layer, and a second current collector along a stacking direction to form an electrode body having the protruding portions protruding from side surfaces of the first active material layer and the second active material layer; Heat is applied to the protruding portion of the electrode body in a direction from the end surface of the electrode body toward the inside of the electrode body, thereby melting the protruding portion at the side surface of the electrode body. The present invention relates to a method for manufacturing a solid-state battery having the above structure.

[0028] The method for manufacturing a solid state battery according to the eighth embodiment can manufacture a solid state battery in which the occurrence of short circuits is suppressed. [Effects of the Invention]

[0029] According to the embodiments of the present disclosure, a solid-state battery in which the occurrence of a short circuit is suppressed and a method for manufacturing the solid-state battery are provided. [Brief explanation of the drawings]

[0030] [Figure 1] FIG. 1 is a perspective view of a solid state battery according to a first embodiment. [Figure 2] FIG. 2 is a front view of the electrode body according to the first embodiment. [Figure 3] FIG. 3 shows a cross-sectional view taken along line III-III in FIG. [Figure 4] FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. [Figure 5] FIG. 5 is a diagram for explaining the method for manufacturing the solid state battery of the first embodiment. [Figure 6] FIG. 6 is a diagram for explaining the method for manufacturing the solid state battery of the first embodiment. [Figure 7] FIG. 7 is a diagram for explaining the method for manufacturing the solid state battery of the first embodiment. [Figure 8] FIG. 8 is a cross-sectional view of an example of an electrode body having a laminated structure in which a plurality of unit electrode bodies having a bipolar structure are connected in series. DETAILED DESCRIPTION OF THE INVENTION

[0031] In the present disclosure, a numerical range indicated using "to" means a range that includes the numerical values ​​before and after "to" as the minimum and maximum values, respectively. In numerical ranges described in stages in the present disclosure, the upper or lower limit value described in a certain numerical range may be replaced with the upper or lower limit value of another numerical range described in stages. In the present disclosure, a combination of two or more preferred embodiments is a more preferred embodiment. In the present disclosure, the term "process" includes not only an independent process, but also a process that cannot be clearly distinguished from other processes, as long as the intended purpose of the process is achieved.

[0032] Hereinafter, embodiments of the solid-state battery and the method for manufacturing the solid-state battery according to the present disclosure will be described with reference to the drawings. In the drawings, the same or corresponding parts are designated by the same reference characters, and description thereof will not be repeated.

[0033] (1) First embodiment (1.1) Solid state battery 1, the solid state battery 1A according to the first embodiment includes an electrode assembly 10A, a plurality of positive electrode current collector tabs 21 (an example of a current collector tab), a plurality of negative electrode current collector tabs 22 (an example of a current collector tab), a positive electrode terminal 31, a negative electrode terminal 32, and an exterior body 40. The electrode assembly 10A is a rectangular parallelepiped object.

[0034] In the first embodiment, the longitudinal direction of the main surface S10 of the electrode body 10A is defined as the X-axis direction. The lateral direction of the main surface S10 of the electrode body 10A is defined as the Y-axis direction. The thickness direction of the electrode body 10A is defined as the Z-axis direction. The X-axis, Y-axis, and Z-axis are perpendicular to each other. The Z-axis direction is an example of a stacking direction. Note that these directions do not limit the orientation of the solid-state battery of the present disclosure during use.

[0035] The positive electrode terminal 31, the multiple positive electrode current collector tabs 21, the electrode assembly 10A, the multiple negative electrode current collector tabs 22, and the negative electrode terminal 32 are arranged in this order along the positive direction of the X-axis. The multiple positive electrode current collector tabs 21 electrically connect the positive electrode terminal 31 to the electrode assembly 10A. The multiple negative electrode current collector tabs 22 electrically connect the negative electrode terminal 32 to the electrode assembly 10A. The exterior housing 40 covers the electrode assembly 10A, the multiple positive electrode current collector tabs 21, and the multiple negative electrode current collector tabs 22. The electrode assembly 10A, the positive electrode current collector tabs 21, and the negative electrode current collector tabs 22 are sealed by the positive electrode terminal 31, the negative electrode terminal 32, and the exterior housing 40.

[0036] (1.1.1) Electrode body The electrode body 10A functions as a power generating element of the solid state battery 1A.

[0037] The electrode body 10A is a rectangular parallelepiped. As shown in FIG. 2, the electrode body 10A has a first side surface portion S10A, a second side surface portion S10B, a third side surface portion S10C, and a fourth side surface portion S10D. The second side surface portion S10B faces the first side surface portion S10A in the Y-axis direction. The third side surface portion S10C connects the first side surface portion S10A and the second side surface portion S10B. The fourth side surface portion S10D connects the first side surface portion S10A and the second side surface portion S10B. The fourth side surface portion S10D faces the third side surface portion S10C in the X-axis direction.

[0038] Each of the first side surface portion S10A, the second side surface portion S10B, the third side surface portion S10C and the fourth side surface portion S10D may be a surface without a step (i.e., a flat surface) or a surface with a step (i.e., a stepped surface).

[0039] The length L1 (thickness) in the Z-axis direction of the electrode body 10A (see FIGS. 3 and 4) is not particularly limited, and is, for example, 18.5 mm.

[0040] 3 and 4, the electrode assembly 10A includes a plurality of unit electrode bodies 10AU. The plurality of unit electrode bodies 10AU are stacked along the Z-axis direction. The plurality of unit electrode bodies 10AU are connected in parallel.

[0041] The unit electrode body 10AU has a monopolar layer structure. Specifically, the unit electrode body 10AU has two solid electrolyte layers 11A, two positive electrode active material layers 12, two negative electrode active material layers 13, two positive electrode current collectors 14, and one negative electrode current collector 15. The positive electrode current collector 14, the positive electrode active material layer 12, the solid electrolyte layer 11A, the negative electrode active material layer 13, the negative electrode current collector 15, the negative electrode active material layer 13, the solid electrolyte layer 11A, the positive electrode active material layer 12, and the positive electrode current collector 14 are layered in this order along the Z-axis direction.

[0042] (1.1.1.1) Solid electrolyte layer The solid electrolyte layer 11A includes a support 110A and a solid electrolyte 111. The solid electrolyte 111 is disposed in a portion of the support 110A. More specifically, the solid electrolyte 111 fills the interior of a portion of the support 110A. The solid electrolyte 111 covers a portion of the support 110A.

[0043] The support 110A holds the solid electrolyte 111. The support 110A and the solid electrolyte 111 prevent electrical contact between the positive electrode active material layer 12 and the negative electrode active material layer 13.

[0044] The support 110A has a protruding portion P110A and a non-protruding portion N110. As shown in FIGS. 3 and 4, the protruding portion P110A protrudes relative to each of the end face S12 of the positive electrode active material layer 12 and the end face S13 of the negative electrode active material layer 13. The non-protruding portion N110 is a portion of the support 110A that is not the protruding portion P110A. The non-protruding portion N110 does not protrude relative to each of the end face S12 of the positive electrode active material layer 12 and the end face S13 of the negative electrode active material layer 13. The solid electrolyte 111 is not disposed in the protruding portion P110A. The solid electrolyte 111 is disposed in the non-protruding portion N110.

[0045] In the present disclosure, "no solid electrolyte is disposed in the protruding portions" means that the volume of the solid electrolyte disposed in the protruding portions is 10% or less of the volume of the protruding portions.

[0046] The number of pores in the support body 110A in the protruding portion P110A is smaller than the number of pores in the support body 110A in the non-protruding portion N110. More specifically, in the first embodiment, the protruding portion P110A is a portion where the support body 110A is melted, and the non-protruding portion N110 is a portion where the support body 110A is not melted.

[0047] (1.1.1.1.1)Protruding parts In the first embodiment, the protruding portions P110A are made of a non-porous resin. The support 110A of the protruding portions P110A may or may not have pores. In the first side surface portion S10A (see FIG. 4) and the third side surface portion S10C (see FIG. 3), the protruding portions P110A of adjacent solid electrolyte layers 11A in the unit electrode body 10AU are fused together. In the second side surface portion S10B (see FIG. 4) and the fourth side surface portion S10D (see FIG. 3), the protruding portions P110A of adjacent solid electrolyte layers 11A between two adjacent unit electrode bodies 10AU are fused together. In the first embodiment, the multiple protruding portions P110A form a film-like material.

[0048] 3 and 4, the protruding portion P110A is arranged to cover the entire surfaces of the first side surface portion S10A, the second side surface portion S10B, the third side surface portion S10C, and the fourth side surface portion S10D of the electrode body 10A. As shown in Fig. 3, the protruding portion P110A is arranged to connect to the positive electrode current collector tab 21 and the negative electrode current collector tab 22 on the third side surface portion S10C and the fourth side surface portion S10D. The protruding portion P110A is in contact with the positive electrode current collector tab 21 and the negative electrode current collector tab 22.

[0049] The protruding portion P110A may or may not be in contact with at least a portion of each of the first side surface portion S10A, the second side surface portion S10B, the third side surface portion S10C, and the fourth side surface portion S10D of the electrode body 10A.

[0050] In the third side surface portion S10C and the fourth side surface portion S10D, the maximum length L2 (maximum thickness) of the protruding portion P110A in the X-axis direction (see FIG. 3) is not particularly limited and may be 0.05 mm to 0.20 mm. In the first side surface portion S10A and the second side surface portion S10B, the maximum length L3 (maximum thickness) of the protruding portion P110A in the Y-axis direction (see FIG. 4) is not particularly limited and may be 0.2 mm to 1.0 mm.

[0051] The material of the protruding portion P110A is the same as the material of the non-protruding portion N110, which will be described later.

[0052] (1.1.1.1.2) Non-protruding area The non-protruding portion N110 is made of a porous resin body. The support 110A of the non-protruding portion N110 has a plurality of pores.

[0053] The pore size of the support 110A of the non-protruding portion N110 is not particularly limited, and may be 1 μm to 15 μm from the viewpoint of further reducing the battery resistance of the solid state battery 1A, etc. The pore size of the support 110A of the non-protruding portion N110 is measured by the bubble point method (JIS K 3832).

[0054] The basis weight of the support 110A of the non-protruding portion N110 is not particularly limited, and is set to 0.10 mg / cm from the viewpoint of further reducing the battery resistance of the solid state battery 1A. 2 ~0.80mg / cm 2 The basis weight of the support 110A of the non-protruding portion N110 can be obtained by cutting out a sheet of a certain area from the non-protruding portion N110 and calculating the mass per area of ​​the cut-out sheet.

[0055] The porosity of the support 110A of the non-protruding portions N110 is not particularly limited, and may be 30% to 95%, or 30% to 70%, from the viewpoint of further reducing the battery resistance of the solid state battery 1A. "Porosity" refers to the volume of voids inside the support 110A of the non-protruding portions N110 relative to the total volume of the support 110A of the non-protruding portions N110. The porosity of the support 110A of the non-protruding portions N110 is obtained by calculating the volume of voids from the difference between the actual volume of the support 110A of the non-protruding portions N110 and the volume calculated from the specific gravity of the material, and then calculating the ratio of voids to the actual volume of the support 110A of the non-protruding portions N110.

[0056] The length (thickness) of the non-protruding portion N110 in the Z direction is not particularly limited, and may be 10 μm to 30 μm, or may be 10 μm to 15 μm. The thickness of the non-protruding portion N110 is measured using a bench micrometer.

[0057] The non-protruding portion N110 may be made of a non-woven fabric, a porous film, a mesh sheet, etc. The non-protruding portion N110 is preferably made of a non-woven fabric.

[0058] The term "porous film" refers to a resin film that does not contain resin fibers and has a plurality of pores. The term "mesh sheet" refers to a woven fabric that contains a plurality of resin fibers and has pores between the resin fibers.

[0059] The nonwoven fabric is not particularly limited, and examples thereof include meltblown nonwoven fabric, spunbond nonwoven fabric, carded nonwoven fabric, parallel nonwoven fabric, cross nonwoven fabric, random nonwoven fabric, spunlaid nonwoven fabric, flash-spun nonwoven fabric, chemically bonded nonwoven fabric, hydroentangled nonwoven fabric, needle-punched nonwoven fabric, stitch-bonded nonwoven fabric, thermally bonded nonwoven fabric, burst fiber nonwoven fabric, tow-spread nonwoven fabric, and film-split nonwoven fabric. Among these, the type of nonwoven fabric is preferably a meltblown nonwoven fabric. Meltblown nonwoven fabrics are made of ultrafine fibers (for example, fiber diameters of 1 μm to 6 μm). Therefore, even if the basis weight of a meltblown nonwoven fabric is low, the number of fibers contained in the nonwoven fabric is large. As a result, it is easy to obtain a nonwoven fabric whose pore size, basis weight, and porosity are each within the above ranges.

[0060] Nonwoven fabrics are made of fibers. The diameter and length of the fibers are not particularly limited. The fibers may be long or short. The cross-sectional shape of the fibers is not particularly limited, and may be circular, elliptical, irregular, or the like.

[0061] Examples of fiber materials include resin, glass, etc. Examples of resin include polyester-based resin (e.g., polyethylene terephthalate (PET)), polyolefin-based resin (e.g., polyethylene (PE) or polypropylene (PP)), or polyamide-based resin (e.g., nylon or aramid).

[0062] Examples of materials for the porous film include polyolefin resins (such as polyethylene (PE) or polypropylene (PP)).

[0063] The mesh sheet is made of fibers, and examples of the fibers of the mesh sheet include the same fibers as those exemplified as the fibers of the nonwoven fabric.

[0064] (1.1.1.1.3) Solid electrolyte The solid electrolyte 111 is not particularly limited and may be an aggregate of a plurality of particles. The particle size is not particularly limited as long as it is a particle size that can penetrate into the pores of the support 110A of the non-protruding portions N110, and may be 0.05 μm to 3.0 μm. The particle size is preferably smaller than the thickness of the non-protruding portions N110. The ratio of the total volume of the solid electrolyte 111 to the total volume of voids in the support 110A of the non-protruding portions N110 may be 50 vol% or more, 70 vol% or more, or even 90 vol%. The particle size can be obtained by observing the cross section of the solid electrolyte layer 11A with a scanning electron microscope (SEM), randomly selecting particles, and measuring the average particle size.

[0065] The solid electrolyte 111 preferably includes one selected from the group consisting of a sulfide solid electrolyte, an oxide solid electrolyte, and a halide solid electrolyte. The solid electrolyte 111 may be a known solid electrolyte.

[0066] (1.1.1.1.4) Binder The solid electrolyte layer may further include a binder. The binder may be used for bonding between solid electrolyte layers. The binder may be used for bonding between the solid electrolyte 111 and the positive electrode active material layer 12 or the negative electrode active material layer 13. Examples of the binder include a vinyl halide resin (e.g., polyvinylidene fluoride (PVdF)), rubbers (e.g., acrylate butadiene rubber (ABR), styrene-butadiene rubber (SBR), etc.), and a polyolefin resin (e.g., polyethylene (PE), polypropylene (PP), etc.).

[0067] (1.1.1.2) Positive electrode active material layer The positive electrode active material layer 12 contains a positive electrode active material. The positive electrode active material layer 12 may contain at least one of a positive electrode solid electrolyte, a conductive additive, and a binder, as necessary.

[0068] The positive electrode active material preferably contains a lithium composite oxide. The lithium composite oxide may contain at least one element selected from the group consisting of F, Cl, N, S, Br, and I. The lithium composite oxide may have a crystal structure belonging to at least one space group selected from the space groups R-3m, Immm, and P63-mmc. The lithium composite oxide may have an O2-type structure in which the transition metal, oxygen, and lithium are primarily arranged. The positive electrode active material may be a known positive electrode active material.

[0069] Examples of the conductive additive that can be used in the positive electrode active material layer include the same ones as those exemplified as the conductive additive contained in the solid electrolyte layer.

[0070] Examples of conductive additives include carbon materials (e.g., carbon black, carbon nanotubes, graphite, or carbon fluoride), metal materials (e.g., aluminum powder or conductive whiskers), or conductive polymer materials (e.g., polyaniline, polypyrrole, or polythiophene).

[0071] Examples of the binder include the same binders as those exemplified as the binder contained in the solid electrolyte layer.

[0072] (1.1.1.3) Negative electrode active material layer The negative electrode active material layer 13 contains a negative electrode active material. The negative electrode active material layer 13 may contain at least one of a negative electrode solid electrolyte, a conductive additive, and a binder, as necessary.

[0073] Examples of negative electrode active materials include Li-based active materials (e.g., metallic lithium), carbon-based active materials (e.g., graphite), oxide-based active materials (e.g., lithium titanate), and Si-based active materials (e.g., elemental Si).

[0074] Examples of the solid electrolyte for the negative electrode include the same solid electrolytes as those exemplified as the solid electrolyte for the positive electrode that can be used in the positive electrode active material layer.

[0075] Examples of the conductive additive that can be used in the negative electrode active material layer include the same ones as those exemplified as the conductive additive that can be used in the positive electrode active material layer.

[0076] Examples of binders that can be used in the negative electrode active material layer include the same binders as those exemplified as binders that can be used in the positive electrode active material layer.

[0077] (1.1.1.4) Positive electrode current collector The positive electrode current collector 14 collects current from the positive electrode active material layer 12. The material of the positive electrode current collector is not particularly limited, and examples thereof include stainless steel, aluminum, copper, nickel, iron, titanium, and carbon. The positive electrode current collector may be an aluminum alloy foil or an aluminum foil. The aluminum alloy foil and the aluminum foil may be manufactured using powder. The positive electrode current collector may have a foil or mesh shape, for example. The positive electrode current collector may have a buffer layer, an elastic layer, or a PTC (Positive Temperature Coefficient) thermistor layer disposed on its surface.

[0078] (1.1.1.5) Negative electrode current collector The negative electrode current collector 15 collects current from the negative electrode active material layer 13. The material of the negative electrode current collector is not particularly limited, and examples thereof include stainless steel, aluminum, copper, nickel, iron, titanium, and carbon. The negative electrode current collector may be a copper foil. The negative electrode current collector may have a foil or mesh shape, for example. The negative electrode current collector may have a buffer layer, an elastic layer, or a PTC (Positive Temperature Coefficient) thermistor layer disposed on its surface.

[0079] (1.1.2) Positive and negative electrode current collecting tabs The positive electrode current collector tab 21 electrically connects the positive electrode current collector 14 and the positive electrode terminal 31. The positive electrode current collector tab 21 is connected to the positive electrode current collector 14. As shown in FIGS. 2 and 3 , the positive electrode current collector tab 21 protrudes in the negative direction of the X axis from the third side surface portion S10C. More specifically, in the first embodiment, a bundle including a plurality of positive electrode current collector tabs 21 is electrically connected to the positive electrode terminal 31. It is preferable that the positive electrode current collector tab 21 is formed continuously from the positive electrode current collector 14.

[0080] The negative electrode current collector tab 22 electrically connects the negative electrode current collector 15 and the negative electrode terminal 32. The negative electrode current collector tab 22 is connected to the negative electrode current collector 15. As shown in FIGS. 2 and 3 , the negative electrode current collector tab 22 protrudes in the positive direction of the X-axis from the fourth side surface portion S10D. More specifically, in the first embodiment, a bundle including a plurality of negative electrode current collector tabs 22 is electrically connected to the negative electrode terminal 32. It is preferable that the negative electrode current collector tab 22 is formed continuously from the positive electrode current collector 14.

[0081] The material of the negative electrode current collector tab and the positive electrode current collector tab is not particularly limited, and may be a metal (for example, aluminum, stainless steel (SUS), nickel, or the like).

[0082] (1.1.3) Negative and positive terminals The positive electrode terminal 31 and the negative electrode terminal 32 are used to conduct electricity generated in the electrode body to the outside of the solid state battery 1A. The positive electrode terminal 31 and the negative electrode terminal 32 are rectangular parallelepiped objects. Examples of materials for the positive electrode terminal 31 and the negative electrode terminal 32 include metals (e.g., aluminum, stainless steel (SUS), nickel, etc.).

[0083] (1.1.4) Exterior body The exterior body 40 covers the electrode body 10A and seals the electrode body 10A together with the positive terminal 31 and the negative terminal 32. In the first embodiment, the exterior body 40 is a metal container. The exterior body 40 is a rectangular parallelepiped (i.e., square). The exterior body 40 has a first wall facing the third side surface portion S10C of the electrode body 10A and a second wall facing the fourth side surface portion S10D of the electrode body 10A. The first wall has one through-hole. The positive terminal 31 is exposed from the through-hole of the first wall, as shown in FIG. 1. The second wall has one through-hole similar to the first wall. The negative terminal 32 is exposed from the through-hole of the second wall. The material of the exterior body 40 is metal (e.g., aluminum, copper, stainless steel (SUS), nickel, etc.). The exterior body 40 may have an electrical insulator on the surface (inner peripheral wall) facing the electrode body 10A to prevent electrical connection with the electrode body 10A. The electrical insulator may be a layered material or a bag.

[0084] (1.1.5) Purpose Applications of the solid-state battery 1A include power sources for electric devices (e.g., vehicles, electronic devices, or electricity storage devices). Examples of vehicles include electric four-wheeled vehicles, electric two-wheeled vehicles, gasoline-powered automobiles, and diesel-powered automobiles. Examples of electric four-wheeled vehicles include electric vehicles (BEVs), plug-in hybrid vehicles (PHEVs), and hybrid electric vehicles (BEVs). Examples of electric two-wheeled vehicles include electric motorcycles and electrically assisted bicycles. Examples of electronic devices include handheld devices (e.g., smartphones, tablet computers, and audio players), portable devices (e.g., notebook computers and compact disc (CD) players), and mobile devices (e.g., power tools and commercial video cameras). Among these, the solid-state battery 1A is preferably used as a power source for driving hybrid automobiles, plug-in hybrid automobiles, or electric automobiles.

[0085] (1.2) Manufacturing method of solid-state battery The manufacturing method for the solid-state battery of the first embodiment is a method for manufacturing a solid-state battery 1A. The manufacturing method includes a preparation step, a unit electrode body forming step, a first heating step, a stacking step, a second heating step, a connection step, and a sealing step. The preparation step, unit electrode body forming step, first heating step, stacking step, second heating step, connection step, and sealing step are performed in this order.

[0086] (1.2.1) Preparation process In the preparation step, a solid electrolyte sheet 11S is prepared.

[0087] The solid electrolyte sheet 11S is a raw material for the solid electrolyte layer 11A. The solid electrolyte sheet 11S includes a support 110B including a plurality of pores and a solid electrolyte 111. The solid electrolyte 111 is not disposed in the protruding portions P110B that represent the peripheral portions of the support 110B, but is disposed in a portion surrounded by the protruding portions P110B of the support 110B (i.e., a portion corresponding to the non-protruding portions N110) (hereinafter also referred to as the "center portion"). The support 110B is a sheet-like material. The support 110B is similar to the support 110A except that the protruding portions include a plurality of pores. In other words, the protruding portions P110B of the solid electrolyte sheet 11S do not have a history of a porous resin being melted, unlike the protruding portions P110A.

[0088] The method for preparing the solid electrolyte sheet 11S is not particularly limited, and examples thereof include a method of applying a solid electrolyte paste to the center of the support 110B and drying it. The solid electrolyte paste contains the solid electrolyte 111 and a known dispersion medium, and may also contain a binder as needed. The application and drying methods may be known methods.

[0089] (1.2.2) Unit electrode body forming process In the unit electrode body formation step, a positive electrode current collector 14 with a positive electrode current collector tab 21, a positive electrode active material layer 12, a solid electrolyte sheet 11S, a negative electrode active material layer 13, a negative electrode current collector 15 with a negative electrode current collector tab 22, a negative electrode active material layer 13, a solid electrolyte sheet 11S, a positive electrode active material layer 12, and a positive electrode current collector 14 with a positive electrode current collector tab 21 are stacked in this order along the Z-axis direction to form a unit electrode body 10a (see FIG. 5). The unit electrode body 10a has a protruding portion P110B. The protruding portion P110B protrudes from each of the end surface S12 of the positive electrode active material layer 12 and the end surface S13 of the negative electrode active material layer 13. Note that in FIG. 5, a portion of the protruding portion P110B is denoted as a protruding portion P110Bc.

[0090] The electrode unit 10a is similar to the electrode unit 10AU except that the protruding portion P110A is changed to a protruding portion P110B.

[0091] There are no particular limitations on the methods for forming the positive electrode current collector 14 with the positive electrode current collector tab 21, the positive electrode active material layer 12, the negative electrode active material layer 13, and the negative electrode current collector 15 with the negative electrode current collector tab 22, and any known method may be used. There are also no particular limitations on the lamination method, and any known method may be used.

[0092] The length L4 (see FIG. 5) of the protruding portion P110B in the X-axis direction is not particularly limited, and may be 0.5 mm to 7.0 mm.

[0093] Hereinafter, the side surface of the electrode unit 10b corresponding to the third side surface S10C of the electrode unit 10A will also be referred to as "S10c." The protruding portion P110B protruding from the third side surface S10c of the electrode unit 10b will also be referred to as "P110Bc."

[0094] (1.2.4) First heating step In the first heating step, heat is applied to the protruding portion P110Bc of the unit electrode body 10a from the third side surface portion S10c of the unit electrode body 10a toward the inside of the unit electrode body 10b, causing the protruding portion P110Bc to melt at the third side surface portion S10c of the unit electrode body 10a. As a result, the protruding portion P110Bc becomes the protruding portion P110A. Thus, the unit electrode body 10b (see FIG. 5) is obtained.

[0095] The heat input method is not particularly limited, and examples include a heat gun, an infrared lamp, etc. The melting point of the support 110B is preferably 100°C to 150°C.

[0096] (1.2.5) Lamination process In the stacking step, a plurality of unit electrode bodies 10b are stacked in this order along the Z-axis direction to form an electrode body 10c (see FIG. 6). The electrode body 10c is similar to the electrode body 10A except that the protruding portion P110B has a plurality of pores. The electrode body 10c has a plurality of protruding portions P110A. The protruding portions P110A of the electrode body 10c protrude onto each of the end face S12 of the positive electrode active material layer 12 and the end face S13 of the negative electrode active material layer 13.

[0097] The lamination method is not particularly limited, and any known method may be used.

[0098] The length L5 (see FIG. 7) of the protruding portion P110B of the electrode body 10c in the Y-axis direction is not particularly limited and may be 2.0 mm to 7.0 mm. In FIG. 7, the protruding portion P110B is represented as protruding portion P110Ba and protruding portion P110Bb.

[0099] Hereinafter, the side surface of the unit electrode body 10b corresponding to the first side surface S10A of the electrode body 10A will also be referred to as "S10a." The side surface of the unit electrode body 10b corresponding to the second side surface S10B of the electrode body 10A will also be referred to as "S10b." The side surface of the unit electrode body 10b corresponding to the fourth side surface S10D of the electrode body 10A will also be referred to as "S10d." The protruding portion P110B protruding from the first side surface S10a of the unit electrode body 10b will also be referred to as "P110Ba." The protruding portion P110B protruding from the second side surface S10b of the unit electrode body 10b will also be referred to as "P110Bb." The protruding portion P110B protruding from the fourth side surface S10d of the unit electrode body 10b will also be referred to as "P110Bd."

[0100] (1.2.6) Second heating step In the second heating step, heat is applied to the protruding portions P110Ba, P110Bb, and P110Bd of the electrode assembly 10c in a direction from the side portions S10a, S10b, and S10d of the electrode assembly 10c toward the inside of the electrode assembly 10c, causing the protruding portions P110Ba, P110Bb, and P110Bd to melt at the side portions S10a, S10b, and S10d of the electrode assembly 10c. As a result, the protruding portions P110Ba, P110Bb, and P110Bd become the protruding portion P110A. The electrode assembly 10A (see FIGS. 6 and 7) is obtained.

[0101] The heat input method is not particularly limited, and examples thereof include the same methods as those exemplified as the heat input method in the first heating step.

[0102] (1.2.7) Connection process In the connection step, the positive electrode current collecting tabs 21 connected to the electrode body 10A are connected to the positive electrode terminal 31, and the negative electrode current collecting tabs 22 connected to the electrode body 10A are connected to the negative electrode terminal 32. Specifically, in the first embodiment, a first bundle including the positive electrode current collecting tabs 21 is formed, and the first bundle is electrically connected to the positive electrode terminal 31. Similarly, a second bundle including the negative electrode current collecting tabs 22 is formed, and the second bundle is electrically connected to the negative electrode terminal 43.

[0103] The connection method is not particularly limited and may be any known method.

[0104] (1.2.8) Sealing process In the sealing step, the electrode body 10A to which the positive electrode terminal 31 and the negative electrode terminal 32 are connected is sealed with an exterior body 40. In this way, a solid state battery 1A is obtained.

[0105] The sealing method is not particularly limited, and any known method may be used.

[0106] (1.3) Action and effect The effects of the solid state battery 1A will be specifically described below with reference to the drawings. As described with reference to FIGS. 1 to 7, the solid state battery 1A includes an electrode assembly 10A, a positive electrode current collector tab 21, and a negative electrode current collector tab 22. The electrode assembly 10A includes a positive electrode current collector 14, a positive electrode active material layer 12, a solid electrolyte layer 11A, a negative electrode active material layer 13, and a negative electrode current collector 15, which are stacked along the Z-axis direction. The solid electrolyte layer 11A includes a support 110A. The support 110A includes protruding portions P110A and non-protruding portions N110. The number of pores in the support 110A in the protruding portions P110A is smaller than the number of pores in the support 110A in the non-protruding portions N110. The protruding portion P110A prevents electrical contact between the positive electrode active material layer 12 and the negative electrode active material layer 13. As a result, the occurrence of short circuits is suppressed in the solid state battery 1A.

[0107] 1 to 7, the electrode body 10A includes a plurality of unit electrode bodies 10AU stacked along the X-axis direction. Each unit electrode body 10AU includes a positive electrode current collector 14, a positive electrode active material layer 12, a solid electrolyte layer 11A, a negative electrode active material layer 13, and a negative electrode current collector 15. Between two adjacent unit electrode bodies AU, the protruding portions P110A of the adjacent solid electrolyte layers 11A are arranged so as to be connected to each other. That is, between two adjacent unit electrode bodies 10AU, the positive electrode active material layer 12 or the negative electrode active material layer 13 disposed between adjacent solid electrolyte layers 11A is likely to be reliably covered by the protruding portion P110A. As a result, the protruding portion P110A more reliably prevents electrical contact between the positive electrode active material layer 12 and the negative electrode active material layer 13. In addition, the protruding portion P110A more reliably prevents electrical contact between at least one of the positive electrode active material layer 12 and the negative electrode active material layer 13 and the exterior body 40. As a result, the occurrence of short circuits in the solid battery 1A is further suppressed.

[0108] 1 to 7, the unit electrode body 10AU is formed by laminating a positive electrode current collector 14, a positive electrode active material layer 12, a solid electrolyte layer 11A, a negative electrode active material layer 13, a negative electrode current collector 15, a negative electrode active material layer 13, a solid electrolyte layer 11A, a positive electrode active material layer 12, and a positive electrode current collector 14 in this order along the X-axis direction. The protruding portion P110A is arranged within the unit electrode body 10AU to connect adjacent solid electrolyte layers 11A. That is, in the unit electrode body 10AU, the positive electrode active material layer 12 or the negative electrode active material layer 13 arranged between adjacent solid electrolyte layers 11A is likely to be reliably covered by the protruding portion P110A. As a result, the protruding portion P110A more reliably prevents electrical contact between the positive electrode active material layer 12 and the negative electrode active material layer 13. In addition, the protruding portion P110A more reliably prevents electrical contact between at least one of the positive electrode active material layer 12 and the negative electrode active material layer 13 and the exterior body 40. As a result, the occurrence of short circuits in the solid state battery 1A is further suppressed.

[0109] As described with reference to FIGS. 1 to 7, the protruding portion P110A is disposed so as to cover the end face S12 of the positive electrode active material layer 12 and the end face S13 of the negative electrode active material layer . This allows the protruding portion P110A to more reliably prevent electrical contact between the positive electrode active material layer 12 and the negative electrode active material layer 13. The protruding portion P110A to more reliably prevent electrical contact between the positive electrode active material layer 12 and the negative electrode active material layer 13 and the exterior body 40. As a result, the occurrence of short circuits is further suppressed in the solid state battery 1A.

[0110] As described with reference to Figures 1 to 7, the electrode body 10A has a first side surface portion S10A, a second side surface portion S10B, a third side surface portion S10C, and a fourth side surface portion S10D. The positive electrode current collector tab 21 protrudes from the third side surface portion S10C. The negative electrode current collector tab 22 protrudes from the fourth side surface portion S10D. The protruding portion P110A is disposed so as to cover the first side surface portion S10A and the second side surface portion S10B. This ensures that the protruding portion P110A prevents electrical contact between the positive electrode active material layer 12 and the negative electrode active material layer 13 more reliably than when the protruding portion P110A is not disposed so as to cover the first side surface portion S10A and the second side surface portion S10B. The protruding portion P110A more reliably prevents electrical contact between the positive electrode active material layer 12 and the negative electrode active material layer 13 and the exterior body 40. As a result, the occurrence of short circuits in the solid state battery 1A is further reduced.

[0111] 1 to 7, the positive electrode current collector tab 21 protrudes from the third side surface portion S10C. The negative electrode current collector tab 22 protrudes from the fourth side surface portion S10D. The protruding portion P110A is arranged to connect to the positive electrode current collector tab 21 and the negative electrode current collector tab 22 on the third side surface portion S10C and the fourth side surface portion S10D. The positive electrode active material layer 12 or the negative electrode active material layer 13 arranged between the solid electrolyte layer 11A and the positive electrode current collector tab 21 or the negative electrode current collector tab 22 is likely to be reliably covered by the protruding portion P110A. As a result, the protruding portion P110A more reliably prevents electrical contact between the positive electrode active material layer 12 and the negative electrode active material layer 13. The protruding portion P110A more reliably prevents electrical contact between the positive electrode active material layer 12 and the negative electrode active material layer 13 and the exterior body 40. As a result, the occurrence of a short circuit is more suppressed in the solid battery 1A.

[0112] As described with reference to FIGS. 1 to 7, the support 110A of the non-protruding portion N110 is preferably made of nonwoven fabric. As a result, the solid-state battery 1A has more satisfactory battery performance than when the support 110A of the non-protruding portion N110 is not made of nonwoven fabric.

[0113] As described with reference to FIGS. 1 to 7, the manufacturing method of the first embodiment includes a preparation step, a unit electrode body forming step, a first heating step, and a second heating step. The method for manufacturing a solid state battery according to the first embodiment can manufacture a solid state battery 1A in which the occurrence of short circuits is suppressed.

[0114] (2) Variations In the first embodiment, the electrode assembly 10A includes a plurality of unit electrode bodies 10AU, but the present disclosure is not limited to this. The electrode assembly 10A may include one unit electrode body 10AU.

[0115] In the first embodiment, the unit electrode body 10AU is formed by stacking the positive electrode current collector 14, the positive electrode active material layer 12, the solid electrolyte layer 11A, the negative electrode active material layer 13, the negative electrode current collector 15, the negative electrode active material layer 13, the solid electrolyte layer 11A, the positive electrode active material layer 12, and the positive electrode current collector 14 in this order along the Z-axis direction, but the present disclosure is not limited to this. The unit electrode body 10AU may also be formed by stacking the positive electrode current collector 14, the positive electrode active material layer 12, the solid electrolyte layer 11A, the negative electrode active material layer 13, and the negative electrode current collector 15 in this order along the Z-axis direction. The electrode unit 10AU may be formed by stacking the negative electrode current collector 15, the negative electrode active material layer 13, the solid electrolyte layer 11A, the positive electrode active material layer 12, the positive electrode current collector 14, the positive electrode active material layer 12, the solid electrolyte layer 11A, the negative electrode active material layer 13, and the negative electrode current collector 15 in this order along the Z-axis direction. The electrode unit 10AU may further include an insulating layer on the surface of at least one of the positive electrode current collectors 14 opposite to the positive electrode active material layer 12.

[0116] In the first embodiment, adjacent solid electrolyte layers 11A are arranged so as to be connected to each other within a unit electrode body 10AU and between two adjacent unit electrode bodies AU, but the present disclosure is not limited to this. In the present disclosure, adjacent solid electrolyte layers 11A may be arranged so as to be connected to each other either within a unit electrode body 10AU or between two adjacent unit electrode bodies AU. Adjacent solid electrolyte layers 11A do not have to be arranged so as to be connected to each other within a unit electrode body 10AU or between two adjacent unit electrode bodies AU.

[0117] In the first to third embodiments, the stacked structure of the electrode assembly 10A is a structure in which a plurality of unit electrode bodies 10AU having a monopolar structure are connected in parallel, but the present disclosure is not limited to this. The stacked structure of the electrode assembly may be a structure in which a plurality of unit electrode bodies having a monopolar structure are connected in series (hereinafter also referred to as a "monopolar series structure"). In a monopolar series configuration, the electrode assembly has a conductor that electrically connects the positive electrode current collector 14 and the negative electrode current collector 15, and does not have a bundle including a plurality of positive electrode current collector tabs 21 or a plurality of negative electrode current collector tabs 22. The stacked structure of the electrode assembly 10A may be a structure in which a plurality of unit electrode bodies having a bipolar structure are connected in series. An example of an electrode assembly having a structure in which a plurality of unit electrode bodies having a bipolar structure are connected in series is shown in FIG. 8.

[0118] In the first embodiment, the protruding portion P110A is arranged so as to cover the end face S12 of the positive electrode active material layer 12 and the end face S13 of the negative electrode active material layer 13, but the present disclosure is not limited to this. The protruding portion P110A does not have to be arranged so as to cover the end face S12 of the positive electrode active material layer 12 and the end face S13 of the negative electrode active material layer 13.

[0119] In the first embodiment, the protruding portion P110A is arranged to cover the first side surface portion S10A and the second side surface portion S10B, but the present disclosure is not limited to this. The protruding portion P110A does not have to be arranged to cover the first side surface portion S10A and the second side surface portion S10B.

[0120] In the first embodiment, the protruding portion P110A is arranged so as to connect to the positive electrode current collector tab 21 and the negative electrode current collector tab 22 on the third side surface portion S10C and the fourth side surface portion S10D, but the present disclosure is not limited to this. The protruding portion P110A does not have to be arranged so as to connect to the positive electrode current collector tab 21 and the negative electrode current collector tab 22 on the third side surface portion S10C and the fourth side surface portion S10D.

[0121] In the first to third embodiments, the exterior body 40 is a rectangular metal container, but the present disclosure is not limited to this. The exterior body 40 may be a container made of at least one laminate film, or may be a cylindrical metal container.

[0122] In the first embodiment, the protruding portion P110A of the support body 110A is formed by melting the protruding portion P110B, but the present disclosure is not limited to this. The protruding portion P110A of the support body 110A may also be formed by welding a corresponding protruding portion P110A of the support body 110A to a non-protruding portion N110 of a support body that does not have the protruding portion P110A.

[0123] In the first embodiment, the positive electrode current collector 14 and the positive electrode current collector tab 21 are separate bodies, and the negative electrode current collector 15 and the negative electrode current collector tab 22 are separate bodies, but the present disclosure is not limited to this. The positive electrode current collector 14 and the positive electrode current collector tab 21 may be the same body. The negative electrode current collector 15 and the negative electrode current collector tab 22 may be the same body. [Explanation of symbols]

[0124] 1A: solid-state battery, 10A: electrode body, 10AU: unit electrode body, 11A: solid electrolyte layer, 110A, 110B: support, 111: solid electrolyte, 12: positive electrode active material layer, 13: negative electrode active material layer, 14: positive electrode current collector, 15: negative electrode current collector, 21: positive electrode current collector tab, 22: negative electrode current collector tab, 40: exterior body, P110A, P110B: protruding portion

Claims

1. An electrode body and a current collecting tab connected to the electrode body, the electrode body has a positive electrode current collector, a positive electrode active material layer, a solid electrolyte layer, a negative electrode active material layer, and a negative electrode current collector, which are stacked along a stacking direction; the solid electrolyte layer has a support including a plurality of pores; the support has protruding portions protruding from the end faces of the positive electrode active material layer and the negative electrode active material layer, and non-protruding portions that are not the protruding portions, a number of pores in the support in the protruding portions being smaller than a number of pores in the support in the non-protruding portions;

2. the electrode body includes a plurality of unit electrode bodies stacked along the stacking direction, the unit electrode body includes the positive electrode current collector, the positive electrode active material layer, the solid electrolyte layer, the negative electrode active material layer, and the negative electrode current collector, The solid-state battery according to claim 1 , wherein the protruding portions of the solid electrolyte layers adjacent to each other are connected to each other between two adjacent electrode units.

3. the unit electrode body is formed by stacking the positive electrode current collector, the positive electrode active material layer, the solid electrolyte layer, the negative electrode active material layer, the negative electrode current collector, the negative electrode active material layer, the solid electrolyte layer, the positive electrode active material layer, and the positive electrode current collector in this order along the stacking direction, The solid-state battery according to claim 2 , wherein the protruding portions are arranged in the unit electrode body so as to connect adjacent ones of the solid electrolyte layers to each other.

4. The solid-state battery according to claim 1 , wherein the protruding portion is disposed so as to cover at least one end surface of the positive electrode active material layer and the negative electrode active material layer.

5. The electrode body A first side portion; a second side surface portion facing the first side surface portion; a third side surface portion connecting the first side surface portion and the second side surface portion; a fourth side surface portion connecting the first side surface portion and the second side surface portion and facing the third side surface portion; and the current collecting tab protrudes from at least one of the third side surface portion and the fourth side surface portion, The solid-state battery according to claim 1 , wherein the protruding portion is disposed to cover the first side surface portion and the second side surface portion.

6. The electrode body A first side surface portion; a second side surface portion facing the first side surface portion; a third side surface portion connecting the first side surface portion and the second side surface portion; a fourth side surface portion connecting the first side surface portion and the second side surface portion and facing the third side surface portion; and the current collecting tab protrudes from at least one of the third side surface portion and the fourth side surface portion, The solid-state battery according to claim 1 , wherein the protruding portions are arranged on the third side surface portion and the fourth side surface portion so as to be connected to the current collecting tabs.

7. The solid-state battery according to claim 1 , wherein the support of the non-protruding portion is made of a nonwoven fabric.

8. preparing a solid electrolyte sheet including a support including a plurality of pores and a solid electrolyte that is not disposed in a protruding portion that indicates a peripheral portion of the support and that is disposed in a portion of the support that is surrounded by the protruding portion; stacking a first current collector, a first active material layer, the solid electrolyte sheet, a second active material layer, and a second current collector along a stacking direction to form an electrode body having the protruding portions protruding from end faces of the first active material layer and the second active material layer; heat is applied to the protruding portion of the electrode body in a direction from a side surface of the electrode body toward an interior of the electrode body, thereby melting the protruding portion at the side surface of the electrode body; A method for manufacturing a solid-state battery comprising:

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