Battery

Abstract

To provide a battery capable of securing negative electrode capacity, suppressing short circuits, and improving volumetric efficiency.SOLUTION: A battery has a laminate 100 including a cathode current collector layer 110, a cathode active material layer 120, an electrolyte layer 130, and an anode active material layer 140 stacked in this order. At least one end of the laminate 100 has the end faces of the cathode active material layer 120, the electrolyte layer 130, and the anode active material layer 140 each forming a sloping surface heading towards the tip, approaching the cathode current collector layer 110, and, towards the tip end of the laminate, a tip 120b of the sloping surface of the cathode active material layer, a tip 140b of the sloping surface of the anode active material layer, and a tip 130b of the sloping surface of the electrolyte layer are arranged in that order.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to batteries. [Background technology]

[0002] A battery generally has a laminate in which a positive electrode active material layer, an electrolyte layer, and a negative electrode active material layer are stacked. This laminate is manufactured, for example, by applying an electrode mixture slurry or the like to the surface of a current collector layer to form each layer. In the electrode active material layer obtained by applying such an electrode mixture slurry, the edge of the electrode mixture slurry coating film spreads by wetting before the electrode mixture slurry coating film dries, which may cause so-called sagging portions in the electrode active material layer. For example, the following all-solid-state batteries are known.

[0003] Patent Document 1 discloses an all-solid-state secondary battery having a positive electrode layer, a negative electrode layer, and a solid electrolyte layer sandwiched between the positive electrode layer and the negative electrode layer, characterized in that the thickness of the electrolyte layer and the positive electrode layer or the negative electrode layer at their edges is thinner than that of their center. According to the all-solid-state secondary battery in Patent Document 1, by continuously thinning the edges of the electrolyte layer and the positive electrode layer or the negative electrode layer, it is possible to prevent breakage and film tearing of the laminate cell, and to produce a solid-state secondary battery with a laminate film exterior and thick, high-density electrodes. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-116136 Summary of the Invention [Problem to be solved by the invention]

[0005] For example, when a battery is manufactured by coating and laminating a negative electrode active material layer, an electrolyte layer, and a positive electrode active material layer in this order on a negative electrode current collector layer, in order to prevent a short circuit in the battery, specifically to prevent the positive electrode active material layer from contacting the negative electrode current collector layer or the negative electrode active material layer, it is necessary to coat the composite slurry that forms each layer taking into consideration the sagging portions of each layer. In such a battery, the sagging portions of each layer have a multi-stage configuration, which reduces the volumetric efficiency of the battery.

[0006] Furthermore, in order to prevent short circuits in the battery, it is also conceivable to cover the positive electrode active material layer with an electrolyte layer, and then cover the electrolyte layer with a negative electrode active material layer, as in the battery disclosed in Patent Document 1. However, even in such a battery, the sagging portions of each layer are covered by the layer above it, which increases the unnecessary portions of the electrode active material layer and electrolyte layer, thereby reducing the volumetric efficiency of the battery.

[0007] Therefore, an object of the present disclosure is to provide a battery that can ensure negative electrode capacity, suppress short circuits, and improve volumetric efficiency. [Means for solving the problem]

[0008] The present disclosure achieves the above object by the following means.

[0009] <Aspect 1> a laminate in which a positive electrode current collector layer, a positive electrode active material layer, an electrolyte layer, and a negative electrode active material layer are laminated in this order; At least one end of the laminate the end faces of the positive electrode active material layer, the electrolyte layer, and the negative electrode active material layer all form inclined surfaces that approach the positive electrode current collector layer as they approach the tip; and the tip of the inclined surface of the positive electrode active material layer, the tip of the inclined surface of the negative electrode active material layer, and the tip of the inclined surface of the electrolyte layer are arranged in this order toward the tip side of the end of the laminate; battery. <Aspect 2> The battery according to aspect 1, wherein the angle between the tangent direction at the tip of the positive electrode active material layer and the plane direction of the surface of the positive electrode current collector layer is 0.5° to 90°. <Aspect 3> The battery according to any one of aspects 1 and 2, wherein the angle between the tangent direction at the tip of the negative electrode active material layer and the plane direction of the surface of the positive electrode current collector layer is 0.5° to 90°. [Effects of the Invention]

[0010] According to the battery of the present disclosure, it is possible to ensure negative electrode capacity, suppress short circuits, and improve volumetric efficiency. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a schematic diagram illustrating a battery according to the present disclosure. [Figure 2] FIG. 2 is a schematic diagram illustrating a battery according to the prior art. [Figure 3] FIG. 3 is a schematic diagram for explaining a battery according to the prior art. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, embodiments of the present disclosure will be described in detail. Note that the present disclosure is not limited to the following embodiments, and various modifications can be made within the scope of the gist of the present disclosure. In addition, in the description of the drawings, the same elements are given the same reference numerals, and duplicated descriptions will be omitted.

[0013] In the present disclosure, the battery may be a liquid-based battery containing an electrolytic solution as the electrolyte layer, or a solid-state battery having a solid electrolyte layer as the electrolyte layer. In the present disclosure, a "solid-state battery" refers to a battery that uses at least a solid electrolyte as the electrolyte, and therefore a solid-state battery may use a combination of a solid electrolyte and a liquid electrolyte as the electrolyte. In the present disclosure, the battery may also be an all-solid-state battery, i.e., a battery that uses only a solid electrolyte as the electrolyte.

[0014] "battery" The battery of the present disclosure comprises: a laminate in which a positive electrode current collector layer, a positive electrode active material layer, an electrolyte layer, and a negative electrode active material layer are laminated in this order; At least one end of the laminate the end faces of the positive electrode active material layer, the electrolyte layer, and the negative electrode active material layer all form inclined surfaces that approach the positive electrode current collector layer as they approach the tip; and The tip of the inclined surface of the positive electrode active material layer, the tip of the inclined surface of the negative electrode active material layer, and the tip of the inclined surface of the electrolyte layer are arranged in this order toward the tip of the end of the laminate.

[0015] According to the battery of the present disclosure, it is possible to ensure negative electrode capacity, suppress short circuits, and improve volumetric efficiency.

[0016] Without being limited to theory, by positioning the tip of the inclined surface of the negative electrode active material layer closer to the tip of the end of the laminate than the tip of the inclined surface of the positive electrode active material layer, the area of ​​the negative electrode active material layer can be made larger than the area of ​​the positive electrode active material layer, thereby ensuring the negative electrode capacity.

[0017] Furthermore, by positioning the tip of the inclined surface of the electrolyte layer closer to the tip of the end of the laminate than the tip of the inclined surface of the positive electrode active material layer, insulation of the positive electrode active material layer can be ensured, thereby suppressing short circuits in the battery.

[0018] Furthermore, by positioning the tip of the inclined surface of the electrolyte layer closer to the tip of the end of the laminate than the tip of the inclined surface of the negative electrode active material layer, it is possible to prevent the negative electrode active material layer from contacting the positive electrode current collector layer and improve the volumetric efficiency of the battery.

[0019] FIG. 1 is a schematic diagram showing one embodiment of the battery of the present disclosure, but is not limited to this embodiment.

[0020] FIG. 1A is a schematic cross-sectional view of the periphery of one end of a laminate 100 included in a battery 10, and FIG. 1B is a schematic view of the periphery of one end of the laminate 100 included in the battery 10, viewed from the surface side of the negative electrode active material layer. The battery 10 illustrated in FIGS. 1A and 1B has a laminate 100 in which a positive electrode current collector layer 110, a positive electrode active material layer 120, an electrolyte layer 130, and a negative electrode active material layer 140 are stacked in this order. The end face 120a of the positive electrode active material layer forms an inclined surface that approaches the positive electrode current collector layer 110 toward the tip of the positive electrode active material layer. The end face 130a of the electrolyte layer also forms an inclined surface that approaches the positive electrode current collector layer 110 toward the tip of the electrolyte layer, and the end face 140a of the negative electrode active material layer also forms an inclined surface that approaches the positive electrode current collector layer 110 toward the tip of the negative electrode active material layer. 1A and 1B, particularly as shown in Fig. 1B, the tips of the inclined surfaces of the layers are arranged in the following order toward the tip of the end of the laminate 100: tip 120b of the inclined surface of the positive electrode active material layer, tip 140b of the inclined surface of the negative electrode active material layer, and tip 130b of the inclined surface of the electrolyte layer. In Fig. 1B, tip 120b of the inclined surface of the positive electrode active material layer is located at the position shown by the dotted line.

[0021] By positioning the tip 140b of the inclined surface of the negative electrode active material layer closer to the tip of the end of the laminate than the tip 120b of the inclined surface of the positive electrode active material layer, the area of ​​the negative electrode active material layer can be made larger than the area of ​​the positive electrode active material layer, thereby ensuring negative electrode capacity. Furthermore, by positioning the tip 130b of the inclined surface of the electrolyte layer closer to the tip of the end of the laminate than the tip 120b of the inclined surface of the positive electrode active material layer, insulation of the positive electrode active material layer can be ensured, thereby preventing short circuits in the battery. Furthermore, by positioning the tip 130b of the inclined surface of the electrolyte layer closer to the tip of the end of the laminate than the tip 140b of the inclined surface of the negative electrode active material layer, contact between the negative electrode active material layer and the positive electrode current collector layer can be prevented, and the volumetric efficiency of the battery can be improved.

[0022] FIG. 2 is a schematic diagram showing one embodiment of a battery in the prior art, but is not limited to this case.

[0023] FIG. 2A is a cross-sectional schematic diagram of the vicinity of one end of the laminate 100 of the battery 10, and FIG. 2B is a schematic diagram of the vicinity of one end of the laminate 100 of the battery 10, viewed from the surface side of the positive electrode active material layer. The conventional battery illustrated in FIGS. 2A and 2B is obtained by, for example, sequentially coating and drying an electrode composite slurry and a solid electrolyte composite slurry to form a laminate, and each layer has a sagging portion. Specifically, the battery 10 illustrated in FIGS. 2A and 2B has a laminate 100 in which an anode current collector layer 150, an anode active material layer 140, an electrolyte layer 130, and a cathode active material layer 120 are stacked in this order. The end surface 140a of the anode active material layer forms an inclined surface that approaches the anode current collector layer 150 as it approaches the tip of the anode active material layer. The end surface 130a of the electrolyte layer and the end surface 120a of the positive electrode active material layer also form an inclined surface similar to the end surface 140a of the negative electrode active material layer. Each layer has an inclined surface, a so-called sagging portion (the area enclosed by a dotted line in FIG. 2A), and these sagging portions are arranged in a stepped pattern, which reduces the volumetric efficiency of the battery. On the other hand, in the battery 10 shown in FIGS. 2A and 2B, the electrolyte layer and the positive electrode active material layer are formed in this order on top of the negative electrode active material layer having the sagging portion, so that the area of ​​the negative electrode active material layer can be made larger than the area of ​​the positive electrode active material layer, thereby ensuring negative electrode capacity.

[0024] Unlike the present disclosure, the tips of the inclined surfaces of the layers are arranged in the following order toward the tip end of the end of the laminate 100, as shown in FIGS. 2A and 2B, particularly as shown in FIG. 2B: tip 120b of the inclined surface of the positive electrode active material layer, tip 130b of the inclined surface of the electrolyte layer, and tip 140b of the inclined surface of the negative electrode active material layer.

[0025] FIG. 3 is a schematic diagram showing one embodiment of another battery in the prior art, but is not limited to this case.

[0026] FIG. 3A is a schematic cross-sectional view of the periphery of one end of the laminate 100 of the battery 10, and FIG. 3B is a schematic view of the periphery of one end of the laminate 100 of the battery 10, viewed from the surface side of the positive electrode active material layer. The battery 10 shown in FIGS. 3A and 3B has a laminate 100 in which a positive electrode current collector layer 110, a positive electrode active material layer 120, an electrolyte layer 130, and a negative electrode active material layer 140 are stacked in this order. The end surface 120a of the positive electrode active material layer forms an inclined surface that approaches the positive electrode current collector layer 110 toward the tip of the positive electrode active material layer. The end surface 130a of the electrolyte layer and the end surface 140a of the negative electrode active material layer also form an inclined surface similar to the end surface 120a of the positive electrode active material layer. Each layer has an inclined surface, or a so-called sagging portion. The battery shown in Figure 3A has a structure in which the sagging portion of the positive electrode active material layer is covered with an electrolyte layer, and the sagging portion of the electrolyte layer is further covered with a negative electrode active material layer. This reduces the volumetric efficiency of the battery. Furthermore, to prevent the negative electrode active material layer from contacting the positive electrode current collector layer, the tip of the positive electrode current collector layer extends only to the tip of the positive electrode active material layer or the tip of the electrolyte layer.

[0027] Unlike the present disclosure, as shown in Figures 3A and 3B, particularly as shown in Figure 3B, the tips of the inclined surfaces of the layers are arranged in the following order toward the tip end of the end of the laminate 100: tip 120b of the inclined surface of the positive electrode active material layer, tip 130b of the inclined surface of the electrolyte layer, and tip 140b of the inclined surface of the negative electrode active material layer. Note that in Figure 3B, tip 120b of the inclined surface of the positive electrode active material layer and tip 130b of the inclined surface of the electrolyte layer are located at the positions shown by dotted lines.

[0028] In the battery of the present disclosure, at least one end of the laminate may, but is not particularly limited to, have a positive electrode current collector layer that extends beyond the tip of the positive electrode active material layer.

[0029] The laminate 100 included in the battery 10 shown in FIGS. 1A and 1B includes a positive electrode current collector layer 110, a positive electrode active material layer 120, an electrolyte layer 130, and a negative electrode active material layer 140 stacked in this order. The positive electrode current collector layer 110 extends beyond the leading edge 120b of the inclined surface of the positive electrode active material layer. In the battery of the present disclosure, the leading edge 130b of the inclined surface of the electrolyte layer is positioned closer to the leading edge of the end of the laminate than the leading edge 140b of the inclined surface of the negative electrode active material layer. This prevents the negative electrode active material layer from contacting the positive electrode current collector layer, thereby allowing the positive electrode current collector layer to extend. The extending positive electrode current collector layer allows, for example, connection between the positive electrode current collector layer and a current collector terminal.

[0030] In the battery of the present disclosure, the angle between the tangential direction at the tip of the positive electrode active material layer and the plane direction of the surface of the positive electrode current collector layer is not particularly limited, but is preferably 0.5° to 90°. The angle may be, for example, 0.5° or more, 1.0° or more, 5.0° or more, 10° or more, 20° or more, 30° or more, 40° or more, or 50° or more, or may be 90° or less, 80° or less, 70° or less, or 60° or less.

[0031] In the present disclosure, the term "tangent" refers to a tangent in a cross section perpendicular to the plane direction of each layer and perpendicular to a line formed by the tip of each layer.

[0032] 1A and 1B, the angle 120d between the tangential direction at the tip of the positive electrode active material layer and the in-plane direction of the surface of the positive electrode current collector layer will be described. The cross-sectional schematic diagram of the battery in FIG. 1A is a cross-section perpendicular to the in-plane direction of the positive electrode current collector layer 110 and perpendicular to the line formed by the tip 120b of the inclined surface of the positive electrode active material layer, specifically, a cross-section taken at the cutting position shown by the dashed line in FIG. 1B. The angle 120d is the angle between the tangential direction 120c at the tip of the positive electrode active material layer and the in-plane direction of the surface of the positive electrode current collector layer 110 in the cross-section shown in FIG. 1A. The angle 120d is preferably 0.5° to 90°.

[0033] In the battery according to the present disclosure, the angle between the tangential direction at the tip of the negative electrode active material layer and the plane direction of the surface of the positive electrode current collector layer is not particularly limited, but is preferably 0.5° to 90°. The angle may be, for example, 0.5° or more, 1.0° or more, 5.0° or more, 10° or more, 20° or more, 30° or more, 40° or more, or 50° or more, or may be 90° or less, 80° or less, 70° or less, or 60° or less.

[0034] 1A, the angle 140d between the tangential direction at the tip of the negative electrode active material layer and the in-plane direction of the surface of the positive electrode current collector layer will be described. Similar to the angle 120d between the tangential direction at the tip of the positive electrode active material layer and the in-plane direction of the surface of the positive electrode current collector layer, the angle 140d is the angle between the tangential direction 140c at the tip of the negative electrode active material layer and the in-plane direction of the surface of the positive electrode current collector layer 110 in the cross section shown in FIG. 1A. The angle 140d is preferably 0.5° to 90°.

[0035] The tip of the inclined surface of the electrolyte layer may be located, but is not particularly limited to, 1.0 mm to 1.4 mm closer to the end of the stack than the tip of the inclined surface of the positive electrode active material layer, and the tip of the inclined surface of the negative electrode active material layer may be located, but is not particularly limited to, 0.7 mm to 1.4 mm closer to the end of the stack than the tip of the inclined surface of the positive electrode active material layer.

[0036] The battery of the present disclosure can be manufactured by, for example, the following method, but is not limited to this. First, a positive electrode composite slurry is applied to the surface of a positive electrode current collector layer and dried to form a positive electrode active material layer with sagging portions. Next, an electrolyte composite slurry is applied to the surface of the electrolyte layer so as to cover the positive electrode active material layer with sagging portions and dried to form an electrolyte layer. Then, a negative electrode composite slurry is applied to the surface of the electrolyte layer and dried to form a negative electrode active material layer. Here, the application is performed so that the tip of the inclined surface of the negative electrode active material layer is positioned between the tip of the inclined surface of the positive electrode active material layer and the tip of the inclined surface of the electrolyte layer.

[0037] 《Battery; each configuration》 Each component of the battery will be described below.

[0038] In the present disclosure, a "composite" refers to a composition that can constitute an electrode active material layer, etc., either as it is or by further containing other components. Also, in the present disclosure, a "composite slurry" refers to a slurry that contains a dispersion medium in addition to a "composite" and can be applied and dried to form an electrode active material layer, etc.

[0039] In the battery according to the present disclosure, the laminate has a laminate in which a positive electrode current collector layer, a positive electrode active material layer, an electrolyte layer, and a negative electrode active material layer are laminated in this order, and may further have an optional negative electrode current collector layer.

[0040] <Positive electrode current collector layer> The material used for the positive electrode current collector layer is not particularly limited, and any material commonly used for battery current collectors can be appropriately used. Examples of materials used for the positive electrode current collector layer include, but are not limited to, Cu, Ni, Cr, Au, Pt, Ag, Al, Fe, Ti, Zn, Co, stainless steel, and carbon sheet. The positive electrode current collector layer may have a coating layer on its surface for purposes such as adjusting resistance.

[0041] The shape of the positive electrode current collector layer is not particularly limited, but examples thereof include foil, plate, mesh, etc. Among these, foil is preferred.

[0042] The thickness of the positive electrode current collector layer is not particularly limited, but may be 0.1 μm or more, or 1 μm or more, and may be 1 mm or less, or 100 μm or less.

[0043] <Cathode active material layer> The positive electrode active material layer contains at least a positive electrode active material, and may further contain, as desired, a solid electrolyte, a conductive additive, a binder, and the like.

[0044] (Cathode active material) The material of the positive electrode active material is not particularly limited as long as it can absorb and release lithium ions. Examples of the positive electrode active material include lithium cobalt oxide (LiCoO), lithium nickel oxide (LiNiO), lithium manganese oxide (LiMnO), and nickel-cobalt-manganese oxide (NCM:LiCO 1 / 3 Ni 1 / 3 Mn 1 / 3 O2), lithium nickel-cobalt-aluminate (LiNi 0.8 (CoAl) 0.2 O2), etc., but are not limited to these.

[0045] The positive electrode active material may have a coating layer, although it is not particularly limited. The coating layer is a layer containing a substance that has lithium ion conductivity, low reactivity with the positive electrode active material and the solid electrolyte, and can maintain the shape of the coating layer without flowing even when in contact with the active material and the solid electrolyte. Specific examples of materials that constitute the coating layer include LiNbO3 and Li4Ti5O 12 , Li3PO4, etc., but are not limited to these.

[0046] The shape of the positive electrode active material is not particularly limited as long as it is a general shape for a positive electrode active material of a battery. The positive electrode active material may be, for example, in the form of particles. The positive electrode active material may be in the form of primary particles or secondary particles formed by agglomeration of a plurality of primary particles. The average particle diameter D of the positive electrode active material 50 The average particle size D may be, for example, 1 nm or more, 5 nm or more, or 10 nm or more, and may be 500 μm or less, 100 μm or less, 50 μm or less, or 30 μm or less. 50 is the particle size (median size) at 50% cumulative value in the volume-based particle size distribution determined by laser diffraction / scattering method.

[0047] (solid electrolyte) The material of the solid electrolyte is not particularly limited, but may be a sulfide solid electrolyte, an oxide solid electrolyte, a polymer electrolyte, or the like.

[0048] Examples of sulfide solid electrolytes include, but are not limited to, sulfide-based amorphous solid electrolytes, sulfide-based crystalline solid electrolytes, and argyrodite-type solid electrolytes. Specific examples of sulfide solid electrolytes include Li2S-P2S5-based (Li7P3S 11 , Li3PS4, Li8P2S9, etc.), Li2S-SiS2, LiI-Li2S-SiS2, LiI-Li2S-P2S5, LiI-LiBr-Li2S-P2S5, Li2S-P2S5-GeS2(Li 13 GeP3S 16 , Li 10 GeP2S 12 ), LiI-Li2S-P2O5, LiI-Li3PO4-P2S5, Li 7-x PS 6-x Cl x etc.; or combinations thereof, but are not limited to these.

[0049] An example of an oxide solid electrolyte is Li7La3Zr2O 12 , Li 7-x La3Zr 1-x Nb x O 12 , Li 7-3x La3Zr2Al x O 12 , Li 3x La 2 / 3-x TiO3, Li 1+x Al x Ti 2-x (PO4)3, Li 1+x Al x Ge 2-x (PO4)3, Li3PO4, or Li 3+x PO 4-x N x (LiPON), etc.; or combinations thereof.

[0050] The sulfide solid electrolyte and the oxide solid electrolyte may be glass or crystallized glass (glass ceramics).

[0051] Examples of polymer electrolytes include, but are not limited to, polyethylene oxide (PEO), polypropylene oxide (PPO), and copolymers thereof.

[0052] (Conductive additive) The conductive additive is not particularly limited. The conductive additive may be, for example, vapor grown carbon fiber (VGCF), acetylene black (AB), ketjen black (KB), carbon nanotube (CNT), carbon nanofiber (CNF), etc., but is not limited thereto. The conductive additive may be, for example, particulate or fibrous, and its size is not particularly limited. The conductive additive is not particularly limited, but one type may be used alone, or two or more types may be used in combination.

[0053] (binder) The binder is not particularly limited. The binder may be, for example, polyvinylidene fluoride (PVdF), butadiene rubber (BR), polytetrafluoroethylene (PTFE), styrene butadiene rubber (SBR), or other materials, but is not limited to these. The binder is not particularly limited, and one type may be used alone, or two or more types may be used in combination.

[0054] The shape of the positive electrode active material layer is not particularly limited, and may be, for example, a substantially flat sheet-like positive electrode active material layer. The thickness of the positive electrode active material layer is not particularly limited, and may be, for example, 0.1 μm or more, 1 μm or more, or 10 μm or more, and may be 2 mm or less, 1 mm or less, or 500 μm or less.

[0055] <Electrolyte layer - solid electrolyte layer> The battery of the present disclosure can be a solid-state battery, i.e., have a solid electrolyte layer as an electrolyte layer. The solid electrolyte layer contains at least a solid electrolyte, and may contain a conductive additive, a binder, and the like as necessary. For details about the solid electrolyte, the conductive additive, and the binder, please refer to the description above in "<Positive Electrode Active Material Layer>".

[0056] The thickness of the solid electrolyte layer is not particularly limited, but may be, for example, 0.1 μm or more, 1 μm or more, or 10 μm or more, and may be 2 mm or less, 1 mm or less, or 500 μm or less.

[0057] <Electrolyte layer - separator layer> The battery of the present disclosure can be a liquid battery, i.e., have an electrolyte solution as the electrolyte layer, particularly an electrolyte solution held in a separator layer.

[0058] (electrolyte) The electrolyte is not particularly limited, but preferably contains a supporting salt and a solvent.

[0059] The supporting salt (lithium salt) of the electrolyte solution having lithium ion conductivity is not particularly limited, but examples thereof include inorganic lithium salts and organic lithium salts. Examples of inorganic lithium salts include, but are not limited to, LiPF, LiBF, LiClO, and LiAsF. Examples of organic lithium salts include, but are not limited to, LiCF, SO, LiN(CF, SO), LiN(CF, SO), LiN(FSO), LiC(CF, SO), and LiC(CF, SO).

[0060] The solvent used in the electrolyte solution is not particularly limited, but examples thereof include cyclic carbonates, chain carbonates, etc. Examples of cyclic carbonates include, but are not limited to, ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate (BC), etc. Examples of chain carbonates include, but are not limited to, dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), etc. The electrolyte solution is not particularly limited, but one type may be used alone, or two or more types may be used in combination.

[0061] (separator) The separator is not particularly limited, and any separator commonly used for batteries can be appropriately used, such as a polyolefin-based, polyamide-based, or polyimide-based nonwoven fabric.

[0062] <Negative electrode active material layer> The negative electrode active material layer contains at least a negative electrode active material, and may further contain, as desired, a solid electrolyte, a conductive additive, a binder, and the like.

[0063] (Negative electrode active material) As the negative electrode active material, various materials can be used that have a potential (charge / discharge potential) at which lithium ions are absorbed and released that is lower than that of the positive electrode active material. The material of the negative electrode active material is not particularly limited, and may be metallic lithium or a material capable of absorbing and releasing metal ions such as lithium ions. Examples of materials capable of absorbing and releasing metal ions such as lithium ions include alloy-based negative electrode active materials, carbon materials, and lithium titanate (Li4Ti5O 12 ) and the like can be mentioned, but are not limited to these.

[0064] The alloy-based negative electrode active material is not particularly limited, and examples thereof include Si alloy-based negative electrode active materials and Sn alloy-based negative electrode active materials. Examples of Si alloy-based negative electrode active materials include, but are not limited to, silicon, silicon oxide, silicon carbide, silicon nitride, and solid solutions thereof. The Si alloy-based negative electrode active material can also include metal elements other than silicon, such as Fe, Co, Sb, Bi, Pb, Ni, Cu, Zn, Ge, In, Sn, Ti, etc. The Sn alloy-based negative electrode active material can also include, but is not limited to, tin, tin oxide, tin nitride, and solid solutions thereof. The Sn alloy-based negative electrode active material can also include metal elements other than tin, such as Fe, Co, Sb, Bi, Pb, Ni, Cu, Zn, Ge, In, Ti, Si, etc.

[0065] The carbon material is not particularly limited, and examples thereof include hard carbon, soft carbon, graphite, and the like.

[0066] The shape of the negative electrode active material is not particularly limited, and may be any shape commonly used for negative electrode active materials in batteries. The negative electrode active material may be, for example, in the form of particles or a sheet.

[0067] For the solid electrolyte, the conductive additive, and the binder, reference can be made to the above description of "<Positive electrode active material layer>".

[0068] The shape of the negative electrode active material layer is not particularly limited, and may be, for example, a substantially flat sheet-like negative electrode active material layer. The thickness of the negative electrode active material layer is not particularly limited, and may be, for example, 0.1 μm or more, 1 μm or more, or 10 μm or more, and may be 2 mm or less, 1 mm or less, or 500 μm or less.

[0069] <Negative electrode current collector layer> The material used for the negative electrode current collector layer is not particularly limited, and any material commonly used for battery current collectors can be appropriately used. Examples of materials used for the negative electrode current collector layer include, but are not limited to, Cu, Ni, Cr, Au, Pt, Ag, Al, Fe, Ti, Zn, Co, stainless steel, and carbon sheet. The negative electrode current collector layer may have a coating layer on its surface for the purpose of adjusting resistance, etc.

[0070] The shape of the negative electrode current collector layer is not particularly limited, but examples thereof include foil, plate, mesh, etc. Among these, foil is preferred.

[0071] The thickness of the negative electrode current collector layer is not particularly limited, but may be 0.1 μm or more, or 1 μm or more, and may be 1 mm or less, or 100 μm or less.

[0072] <Battery uses, etc.> The battery in the present disclosure is not particularly limited, and may be a lithium-ion secondary battery. The battery in the present disclosure may be, for example, an in-vehicle battery, or may be used as a power source for a moving body other than a vehicle (for example, a train, a ship, or an airplane), or may be used as a power source for an electrical appliance such as an information processing device.

[0073] While embodiments of the battery of the present disclosure have been described, those skilled in the art will recognize that modifications are possible without departing from the scope of the claims. [Explanation of symbols]

[0074] 10 batteries 100 laminate 110 Positive electrode current collector layer 120 Cathode active material layer 120a End surface of positive electrode active material layer 120b Tip of the inclined surface of the positive electrode active material layer 120c Tangential direction at the tip of the positive electrode active material layer 120d Angle between the tangential direction at the tip of the positive electrode active material layer and the plane direction of the surface of the positive electrode current collector layer 130 Electrolyte layer 130a End face of electrolyte layer 130b Tip of the inclined surface of the electrolyte layer 140 Negative electrode active material layer 140a End surface of negative electrode active material layer 140b Tip of the inclined surface of the negative electrode active material layer 140c Tangential direction at the tip of the negative electrode active material layer 140d Angle between the tangential direction at the tip of the negative electrode active material layer and the plane direction of the surface of the positive electrode current collector layer 150 Negative electrode current collector layer

Claims

1. a laminate in which a positive electrode current collector layer, a positive electrode active material layer, an electrolyte layer, and a negative electrode active material layer are laminated in this order; At least one end of the laminate The end faces of the positive electrode active material layer, the electrolyte layer, and the negative electrode active material layer all form inclined surfaces that approach the positive electrode current collector layer as they approach the tip, and the tip of the inclined surface of the positive electrode active material layer, the tip of the inclined surface of the negative electrode active material layer, and the tip of the inclined surface of the electrolyte layer are arranged in this order toward the tip side of the end of the laminate; battery.

2. 2. The battery according to claim 1, wherein an angle between a tangent direction at the tip of the positive electrode active material layer and a plane direction of the surface of the positive electrode current collector layer is 0.5° to 90°.

3. 3. The battery according to claim 1, wherein an angle between a tangent direction at the tip of the negative electrode active material layer and a plane direction of the surface of the positive electrode current collector layer is 0.5° to 90°.

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