Solid-state battery and method for producing the same, and battery module

Abstract

To provide a solid-state battery that can effectively dissipate heat generated by an electrode stack.SOLUTION: An electrode stack 110 of a solid-state battery 10 of the present disclosure includes a first current collector layer 111, a first electrode active material layer 112, a solid electrolyte layer 113, a second electrode active material layer 114 and a second current collector layer 115, in this order. An insulating member 120 is disposed on at least part of the edge face of the electrode stack, and the second current collector layer is contacted with the insulating member. A method, of the present disclosure, for producing the solid-state battery includes the following steps: forming a preliminary stack; applying the insulating member onto at least part of the edge face of the preliminary stack; after application of the insulating member, stacking the second current collector layer onto the preliminary stack to form the electrode stack; and bringing the second current collector layer into contact with the insulating member.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a solid-state battery, a manufacturing method thereof, and a battery module. [Background technology]

[0002] In the automotive industry, growing environmental awareness has led to the development of electric vehicles, hybrid vehicles, etc., and this has led to a growing demand for high-voltage secondary batteries. Meanwhile, in the field of portable electronic devices, the widespread adoption and development of these devices has led to a demand for small, lightweight, high-capacity secondary batteries capable of long periods of continuous operation.

[0003] Known high-voltage, high-capacity batteries include, for example, batteries that include an electrode stack having, in this order, a negative electrode current collector layer, a negative electrode active material layer, a solid electrolyte layer, a positive electrode active material layer, and a positive electrode current collector layer.

[0004] In such batteries, for example, if the current collector layer of one electrode extends beyond the electrode stack, it may come into contact with the current collector layer and / or active material layer of the other electrode, resulting in a short circuit. The portion of the current collector layer extending beyond the electrode stack is also called a current collector tab. This short circuit is particularly likely to occur when the area of ​​the current collector layer of one electrode is larger than the area of ​​the current collector layer of the other electrode. Therefore, technologies to prevent such short circuits have been developed.

[0005] For example, Patent Document 1 discloses a method for manufacturing a stacked all-solid-state battery, which includes preparing a first stacked body in which a solid electrolyte layer, a first active material layer (electrode active material layer), a first current collector layer having a first current collector tab extending to the side of the stacked all-solid-state battery, a first active material layer, and a solid electrolyte layer are stacked in this order; applying an insulating coating liquid to an end of the first stacked body to form an insulating part (insulating member); and assembling the first stacked body with the insulating part formed thereon, a second active material layer, and a second current collector tab extending to the side of the stacked all-solid-state battery. and a second current collector layer having a second current collecting tab, to prepare a battery structure (electrode laminate) having a plurality of second laminates, each of which is formed by laminating a second current collector layer having a second current collecting tab, a second active material layer, a solid electrolyte layer, a first active material layer, a first current collector layer having a first current collecting tab, a first active material layer, a solid electrolyte layer, and a second active material layer in this order; and joining a plurality of second current collecting tabs extending from the plurality of second current collectors in the battery structure. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 2018-049696 Summary of the Invention [Problem to be solved by the invention]

[0007] In a battery including an electrode laminate, the electrode laminate may generate heat during charging and discharging, and the current collector layer of the electrode laminate in particular is likely to reach high temperatures. Such heat generation can deteriorate battery performance, so it is desirable to be able to effectively dissipate the heat generated in the electrode laminate.

[0008] An object of the present disclosure is to provide a solid-state battery capable of effectively dissipating heat generated in an electrode stack, a method for manufacturing the same, and a battery module having such a solid-state battery. [Means for solving the problem]

[0009] The present inventors have found that the above problems can be solved by the following means. <Aspect 1> A solid-state battery having an electrode stack, the electrode laminate has, in this order, a first current collector layer, a first electrode active material layer, a solid electrolyte layer, a second electrode active material layer, and a second current collector layer; an insulating member is disposed on at least a part of an end surface of the electrode stack; the second current collector layer extends from an end surface of the electrode stack on which the insulating member is disposed, and The second current collector layer is in contact with the insulating member. solid state battery. <Aspect 2> the electrode laminate has the first electrode active material layer, the solid electrolyte layer, the second electrode active material layer, and the second current collector layer, in this order, on both sides of the first current collector layer; One of the second current collector layers is in contact with the insulating member. 2. The solid-state battery of embodiment 1. <Aspect 3> the insulating member is disposed on an end surface of the electrode stack, spanning from one of the second electrode active material layers to the other of the second electrode active material layers; and the second current collector layer is in contact with the insulating member over 50% or more of the surface area of ​​the insulating member; 3. The solid-state battery of embodiment 2. <Aspect 4> 4. The solid state battery according to any one of aspects 1 to 3, wherein the insulating member comprises a thermoplastic resin. <Aspect 5> 4. The solid state battery according to any one of aspects 1 to 3, wherein the insulating member includes a mixture of a resin and an insulating filler, and the insulating filler has a higher thermal conductivity than the resin. <Aspect 6> 6. The solid-state battery of embodiment 5, wherein the insulating filler is a metal oxide. <Aspect 7> 7. The solid-state battery of any one of aspects 1 to 6, wherein the first current collector layer is a negative electrode current collector layer, the first electrode active material layer is a negative electrode active material layer, the second electrode active material layer is a positive electrode active material layer, and the second current collector layer is a positive electrode current collector layer. <Aspect 8> A battery module having the solid state battery according to any one of embodiments 1 to 7. <Aspect 9> A method for producing the solid state battery according to any one of aspects 1 to 7, comprising the steps of: (a) laminating the first current collector layer, the first electrode active material layer, the solid electrolyte layer, and the second electrode active material layer in this order to form a preliminary laminate; (b) applying the insulating member to at least a portion of an end surface of the pre-laminate; (c) after applying the insulating member, laminating the second current collector layer on the second electrode active material layer of the pre-laminate to form the electrode laminate; and (d) contacting the second current collector layer with the insulating member. <Aspect 10> the insulating member contains a thermoplastic resin, In the step (d), the second current collector layer is pressed against the insulating member while being heated to adhere it to the insulating member. 10. The method of embodiment 9. <Aspect 11> A solid-state battery having an electrode stack, the electrode laminate has, in this order, a first current collector layer, a first electrode active material layer, a solid electrolyte layer, a second electrode active material layer, and a second current collector layer; an insulating member is disposed on at least a part of an end surface of the electrode stack; The insulating member includes a mixture of a resin and an insulating filler, and The thermal conductivity of the insulating filler is higher than the thermal conductivity of the resin. solid state battery. [Effects of the Invention]

[0010] According to the present disclosure, it is possible to provide a solid-state battery capable of effectively dissipating heat generated in an electrode stack, a method for manufacturing the same, and a battery module having such a solid-state battery. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a schematic plan view showing an example of a solid state battery according to the present disclosure. [Figure 2] FIG. 2 is a schematic cross-sectional view showing an example of an arrangement of insulating members in the solid state battery of the present disclosure. [Figure 3] FIG. 3 is a schematic cross-sectional view showing an example of an embodiment in which the insulating member contains a mixture of a resin and an insulating filler in the solid state battery of the present disclosure. [Figure 4] FIG. 4 is a schematic perspective view showing an example of a battery module according to the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. Note that the present disclosure is not limited to the following embodiments, and various modifications can be made within the scope of the present disclosure. Furthermore, the dimensional relationships in the drawings do not reflect the actual dimensional relationships.

[0013] 《Solid-state battery》 As illustrated in FIG. 1 , a solid state battery 10 according to the present disclosure includes an electrode stack 110. As illustrated in FIG. 2 , the electrode stack 110 includes a first current collector layer 111, a first electrode active material layer 112, a solid electrolyte layer 113, a second electrode active material layer 114, and a second current collector layer 115, in this order. An insulating member 120 is disposed on at least a portion of an end surface of the electrode stack 110. A second current collector layer 115 extends from the end surface of the electrode stack 110 on which the insulating member 120 is disposed, and the second current collector layer 115 is in contact with the end surface of the insulating member 120. FIG. 2 is a schematic cross-sectional view showing an enlarged view of the insulating member 120 portion of the solid state battery 10 according to the present disclosure.

[0014] As described above, in a battery including an electrode laminate, the electrode laminate may generate heat during charging and discharging, and the current collector layer of the electrode laminate in particular is likely to reach a high temperature. The present inventors have discovered that by bringing the second current collector layer extending from the end face of the electrode laminate into contact with an insulating member, heat generated in the electrode laminate can be dissipated more effectively than when the electrode laminate and the second current collector layer extending from the end face of the electrode laminate are separated by, for example, air.

[0015] Furthermore, when an insulating member is formed on the end surface of the electrode stack, the current collecting tabs are joined to each other at a distance from the electrode stack due to the insulating member, resulting in a decrease in the volumetric efficiency of the battery. The present inventors have discovered that by bringing the insulating member into contact with a second current collecting layer extending from the end surface of the electrode stack, the positions at which the current collecting tabs are joined to each other can be brought closer to the electrode stack, thereby improving the volumetric efficiency of the battery.

[0016] In the present disclosure, in particular, the second current collector layer may be bonded to the insulating member. This configuration facilitates adhesion of the second current collector layer to the insulating member, thereby enabling more effective dissipation of heat generated in the electrode stack. In the present disclosure, bonding includes bonding with an adhesive, adhesion with tape or a material having tackiness, thermal welding, etc.

[0017] 2 , when the electrode stack 110 has a first electrode active material layer 112, a solid electrolyte layer 113, a second electrode active material layer 114, and a second current collector layer 115 on both sides of a first current collector layer 111 in this order, an insulating member 120 may be disposed on the end face of the electrode stack 110, spanning from one second electrode active material layer 114 to the other second electrode active material layer 114, and the second current collector layer 115 may be in contact with the insulating member 120 over 50% or more of the surface area of ​​the insulating member 120. This configuration effectively prevents short circuits due to contact between the second current collector layer 115 and the first current collector layer 111 and first electrode active material layer 112, and more effectively dissipates heat generated in the electrode stack. Furthermore, the volumetric efficiency of the battery can be further improved. In this case, at least a part of the contact area between the second current collector layer 115 and the insulating member 120 may be bonded, and in particular the entire area may be bonded.

[0018] In the context of 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. Alternatively, the solid-state battery of the present disclosure may be an all-solid-state battery, i.e., a battery that uses only a solid electrolyte as the electrolyte.

[0019] The solid-state battery of the present disclosure may be a lithium-ion secondary battery. Examples of uses of the battery include power sources for vehicles such as hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), electric vehicles (BEVs), gasoline-powered vehicles, and diesel-powered vehicles. In particular, the battery is preferably used as a driving power source for hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), or electric vehicles (BEVs). The battery of the present disclosure may also be used as a power source for mobile objects other than vehicles (e.g., trains, ships, and aircraft), or as a power source for electrical appliances such as information processing devices.

[0020] The elements constituting the solid-state battery of the present disclosure will be described below.

[0021] <Electrode laminate> The solid state battery 10 of the present disclosure has an electrode stack 110. The electrode stack functions as the power generating element of the battery.

[0022] The electrode stack 110 has a first current collector layer 111, a first electrode active material layer 112, a solid electrolyte layer 113, a second electrode active material layer 114, and a second current collector layer 115 in this order. As illustrated in FIG. 2 , the electrode stack 110 may have a first electrode active material layer 112, a solid electrolyte layer 113, a second electrode active material layer 114, and a second current collector layer 115 in this order on both sides of a first current collector layer 111. That is, the electrode stack 110 may have a second current collector layer 115, a second electrode active material layer 114, a solid electrolyte layer 113, a first electrode active material layer 112, a first current collector layer 111, a first electrode active material layer 112, a solid electrolyte layer 113, a second electrode active material layer 114, and a second current collector layer 115 in this order, and one of the second current collector layers 115 may be in contact with an end face of the insulating member 120. Note that, although FIG. 2 illustrates an example in which two electrode laminates each having a first electrode active material layer 112, a solid electrolyte layer 113, a second electrode active material layer 114, and a second current collector layer 115 in this order are laminated on both sides of a first current collector layer 111, the number of electrode laminates in the solid state battery of the present disclosure is not limited to this.

[0023] The first current collector layer may be a negative electrode current collector layer, the first electrode active material layer may be a negative electrode active material layer, the second electrode active material layer may be a positive electrode active material layer, and the second current collector layer may be a positive electrode current collector layer. That is, the electrode laminate may have a negative electrode current collector layer, a negative electrode active material layer, a solid electrolyte layer, a positive electrode active material layer, and a positive electrode current collector layer in this order.

[0024] The shape of the electrode laminate is not particularly limited, and may have, for example, a top surface, a bottom surface opposite the top surface, and four side surfaces connecting the top surface and the bottom surface. The shape of the top surface is not particularly limited, and examples thereof include quadrilaterals such as squares, rectangles, rhombuses, trapezoids, and parallelograms. The shape of the top surface may also be polygonal other than a quadrilateral, or may have a curved shape such as a circle. The shape of the bottom surface may be the same as the shape of the top surface. The shape of the side surface is not particularly limited, and examples thereof include quadrilaterals such as squares, rectangles, rhombuses, trapezoids, and parallelograms.

[0025] The size of the electrode laminate is not particularly limited, and can be appropriately designed depending on, for example, the desired battery characteristics.

[0026] Hereinafter, each of the components that can constitute the electrode stack according to the present disclosure will be described.

[0027] To facilitate understanding of the present disclosure, the components of an electrode stack of a solid-state lithium-ion secondary battery will be described as an example, but the solid-state battery of the present disclosure is not limited to a lithium-ion secondary battery.

[0028] (Positive electrode current collector layer) The conductive material used for the positive electrode current collector layer is not particularly limited, and may be, for example, SUS, aluminum, copper, nickel, iron, titanium, carbon, or the like.

[0029] The shape of the positive electrode current collector layer is not particularly limited, and examples thereof include foil, plate, mesh, etc. Among these, the foil shape is preferred.

[0030] The positive electrode current collector layer may extend from the end face of the electrode stack, and a plurality of positive electrode current collector layers may be joined at the extending portion.

[0031] (Cathode active material layer) The positive electrode active material layer contains at least a positive electrode active material, and preferably further contains a solid electrolyte described below. In addition, depending on the intended use and purpose, it may contain additives used in positive electrode active material layers of solid-state batteries, such as a conductive additive or a binder.

[0032] The material of the positive electrode active material is not particularly limited. For example, the positive electrode active material may be lithium cobalt oxide (LiCoO2), lithium nickel oxide (LiNiO2), lithium manganese oxide (LiMn2O4), Li 1.5 Co 1 / 3 Ni 1 / 3 Mn 1 / 3 O2, LiCo 1 / 3 Ni 1 / 3 Mn 1 / 3 O2, Li 1+x Mn 2-x-y M y It may be a different element-substituted Li-Mn spinel having a composition represented by O4 (M is one or more metal elements selected from Al, Mg, Co, Fe, Ni, and Zn), or the like.

[0033] The conductive additive is not particularly limited, and may be, for example, a carbon material such as VGCF (Vapor Grown Carbon Fiber) or carbon nanofiber, or a metal material.

[0034] The binder is not particularly limited, and may be, for example, polyvinylidene fluoride (PVdF), carboxymethyl cellulose (CMC), butadiene rubber (BR), styrene butadiene rubber (SBR), or a combination thereof.

[0035] (Solid electrolyte layer) The solid electrolyte layer includes at least a solid electrolyte. The solid electrolyte is not particularly limited, and any material that can be used as a solid electrolyte for a solid-state battery can be used. For example, the solid electrolyte may be a sulfide solid electrolyte, an oxide solid electrolyte, a polymer electrolyte, or the like.

[0036] 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 etc.), LiI-Li2S-P2O5, LiI-Li3PO4-P2S5, Li 7-x PS 6-x Cl x etc.; or combinations thereof, but are not limited to these.

[0037] 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, Li 3+x PO 4-x N x (LiPON), etc., but are not limited to these.

[0038] Polymer electrolytes include, but are not limited to, polyethylene oxide (PEO), polypropylene oxide (PPO), and the like, and copolymers thereof.

[0039] The solid electrolyte may be glass or crystallized glass (glass ceramic). The solid electrolyte layer may contain, in addition to the solid electrolyte described above, a conductive additive, a binder, and the like, as needed. For details about the conductive additive and the binder, see the description of the positive electrode active material layer.

[0040] (Negative electrode active material layer) The negative electrode active material layer contains at least a negative electrode active material, and preferably further contains the above-mentioned solid electrolyte. In addition, depending on the intended use and purpose, it may contain additives used in negative electrode active material layers of solid-state batteries, such as a conductive additive and a binder.

[0041] The material of the negative electrode active material is not particularly limited, but is preferably capable of absorbing and releasing metal ions such as lithium ions. For example, the negative electrode active material may be, but is not limited to, an oxide-based negative electrode active material, an alloy-based negative electrode active material, a carbon material, or the like.

[0042] The oxide-based negative electrode active material is not particularly limited, and examples thereof include lithium titanate (LTO) particles.

[0043] 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 silicon, silicon oxide, silicon carbide, silicon nitride, and solid solutions thereof. The Si alloy-based negative electrode active material can also contain 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 contain tin, tin oxide, tin nitride, or solid solutions thereof. The Sn alloy-based negative electrode active material can also contain elements other than tin, such as Fe, Co, Sb, Bi, Pb, Ni, Cu, Zn, Ge, In, Ti, Si, etc.

[0044] The carbon material is not particularly limited, and examples thereof include hard carbon, soft carbon, graphite, and the like.

[0045] For the solid electrolyte used in the negative electrode active material layer, the above description regarding the solid electrolyte layer can be referred to, and for the conductive additive and binder, the above description regarding the positive electrode active material layer can be referred to.

[0046] (negative electrode current collector layer) The conductive material used for the negative electrode current collector layer is not particularly limited, and may be, for example, SUS, aluminum, copper, nickel, iron, titanium, carbon, or the like, but is not limited to these.

[0047] The shape of the negative electrode current collector layer is not particularly limited, and examples thereof include foil, plate, mesh, etc. Among these, foil is preferred.

[0048] The negative electrode current collector layer may extend from the end face of the electrode stack, and a plurality of negative electrode current collector layers may be joined at the extending portion.

[0049] <Insulating materials> In the solid state battery 10 of the present disclosure, an insulating member 120 is disposed on at least a portion of the end face of the electrode stack 110 .

[0050] The insulating member 120 may contain a thermoplastic resin or may be a thermoplastic resin. This configuration makes it easier to bond the second current collector layer 115 to the insulating member 120. That is, as will be described later, the second current collector layer 115 can be bonded to the insulating member 120 by pressing the second current collector layer 115 against the insulating member 120 while heating it.

[0051] The thermoplastic resin is not particularly limited and may be either a non-reactive type or a reactive type. Examples of non-reactive thermoplastic resins include, but are not particularly limited to, ethylene vinyl acetate (EVA)-based, synthetic rubber-based, olefin-based, polyamide-based, and polyester-based resins such as polyethylene terephthalate (PET). Examples of reactive resins include, but are not particularly limited to, urethane-based resins.

[0052] The insulating member 120 may contain a curable resin or may be a curable resin. The curable resin may have tackiness after curing. By using such a curable resin, the second current collector layer 115 can be easily bonded to the insulating member 120.

[0053] The curable resin is not particularly limited, and examples thereof include thermosetting resins and photocurable resins, such as acrylic and epoxy resins.

[0054] By using such a resin as the insulating member 120, it is easy to arrange the insulating member 120 on the end face of the electrode stack 110.

[0055] The insulating member 120 may be an insulating tape. The insulating tape may be a double-sided tape. By using such an insulating tape, the second current collector layer 115 can be easily adhered to the insulating member 120.

[0056] By using an insulating tape as the insulating member 120, the space occupied by the insulating member 120 is reduced, and therefore the volumetric efficiency of the battery can be further improved.

[0057] 3, the insulating member 120 may include a mixture of a resin 121 and an insulating filler 121, and the thermal conductivity of the insulating filler may be greater than the thermal conductivity of the resin. 8 This means that the electrical resistance is Ω·cm or more. When the insulating member 120 contains the insulating filler 121, heat generated in the electrode stack 110 can be more effectively dissipated to the outside of the battery. FIG. 3 is a schematic cross-sectional view showing an enlarged portion of the insulating member 120 of the solid state battery 10 of the present disclosure. FIG. 3 illustrates an example in which two electrode stacks each having a first electrode active material layer 112, a solid electrolyte layer 113, a second electrode active material layer 114, and a second current collector layer 115 in this order are stacked on either side of the first current collector layer 111, but the number of electrode stacks in the solid state battery of the present disclosure is not limited to this.

[0058] As described above, the current collector layer in particular is prone to high temperatures within the electrode stack 110. Therefore, by arranging the insulating member 120 so as to cover the first current collector layer 111 on the end face of the electrode stack 110, the heat generated in the electrode stack 110 can be dissipated particularly effectively.

[0059] The insulating filler may be a metal oxide, and the metal oxide is not particularly limited, but may be, for example, aluminum oxide.

[0060] The shape, size, etc. of the insulating member 120 are not particularly limited, and can be designed appropriately taking into consideration the ease of contact with the second current collector layer, the volumetric efficiency of the battery, etc. For example, the length of the insulating member 120 in the stacking direction of the electrode stack 110 may be smaller than the thickness of the electrode stack 110. With this configuration, even when forming a battery module including the solid state battery 10 of the present disclosure as described below, the insulating member 120 can be prevented from interfering with the restraint of the electrode stack 110 in the stacking direction.

[0061] <Laminating film> The solid state battery 10 of the present disclosure may have a laminate film 130. The laminate film may house an electrode stack. Specifically, the laminate film may house the electrode stack by rolling it up. The laminate film may also be composed of first and second films, and in this case, the electrode stack may be housed by being sandwiched between the first and second films from above and below in the stacking direction of the electrode stack.

[0062] The laminate film may have a sealant resin layer, a metal layer, and a protective resin layer in this order along the thickness direction. Examples of materials for the sealant resin layer include olefin resins such as polypropylene (PP) and polyethylene (PE). Examples of materials for the metal layer include aluminum, aluminum alloys, and stainless steel. Examples of materials for the protective resin layer include polyethylene terephthalate (PET) and nylon.

[0063] The thickness of each layer constituting the laminate film and the laminate film itself are not particularly limited. The thickness of the sealant resin layer is, for example, 40 μm or more and 100 μm or less. The thickness of the metal layer is, for example, 30 μm or more and 60 μm or less. The thickness of the protective resin layer is, for example, 20 μm or more and 60 μm or less. The thickness of the laminate film is, for example, 80 μm or more and 250 μm or less.

[0064] (Current collector terminal) The solid state battery 10 of the present disclosure may further include a current collecting terminal 140. The current collecting terminal may be electrically connected to the current collecting portion of the electrode stack. The material of the current collecting terminal is not particularly limited as long as it has a current collecting function. As illustrated in FIG. 1, the positive electrode current collecting terminal and the negative electrode current collecting terminal may be disposed on a pair of opposing side surfaces of the electrode stack. The positive electrode current collecting terminal and the negative electrode current collecting terminal may be disposed spaced apart from each other on one side surface of the electrode stack.

[0065] The shape and size of the current collecting terminal are not particularly limited.

[0066] When the solid-state battery according to the present disclosure has a current collecting terminal, the laminate film may house the electrode stack together with the current collecting terminal. Specifically, the laminate film may house the electrode stack together with the current collecting terminal by winding the electrode stack and the current collecting terminal. The laminate film may also be composed of first and second films. In this case, the first and second films may sandwich the electrode stack and the current collecting terminal from above and below in the stacking direction of the electrode stack, housing the electrode stack together with the current collecting terminal.

[0067] <<Solid-state battery manufacturing method>> The disclosed method for manufacturing a solid-state battery includes the following steps: (a) stacking a first current collector layer 111, a first electrode active material layer 112, a solid electrolyte layer 113, and a second electrode active material layer 114 in this order to form a pre-laminate; (b) applying an insulating member 120 to at least a portion of an end face of the pre-laminate; (c) after applying the insulating member, stacking a second current collector layer 115 on the second electrode active material layer of the pre-laminate to form an electrode laminate; and (d) contacting the second current collector layer with the insulating member.

[0068] By using such a method, it is possible to manufacture the solid state battery of the present disclosure with improved volumetric efficiency.

[0069] <Pre-laminate formation process> The method of the present disclosure includes (a) laminating a first current collector layer, a first electrode active material layer, a solid electrolyte layer, and a second electrode active material layer in this order to form a preliminary laminate.

[0070] In the present disclosure, the term "pre-laminate" refers to a laminate having a first current collector layer, a first electrode active material layer, a solid electrolyte layer, and a second electrode active material layer in this order, and which can form an electrode laminate by laminating a second current collector layer thereon.

[0071] The method for laminating each layer is not particularly limited, and examples thereof include dry molding such as powder compaction and wet molding using a slurry. For example, in the case of wet molding, a first electrode mixture slurry capable of forming a first electrode active material layer is first applied to one surface of a first current collector layer and then dried, thereby laminating the first electrode active material layer on the first current collector layer. A solid electrolyte layer can be similarly laminated on the first electrode active material layer by using a solid electrolyte slurry. A second electrode mixture slurry can be similarly laminated on the solid electrolyte layer.

[0072] <Insulating material application process> The disclosed method includes (b) applying an insulating member to at least a portion of the end surface of the pre-laminate.

[0073] The method for applying an insulating member to at least a portion of the end surface of the pre-laminate is not particularly limited. For example, when the insulating member is a thermoplastic resin, a method of applying or immersing molten thermoplastic resin to at least a portion of the end surface of the pre-laminate, followed by solidification, can be used. For example, when the insulating member is a curable resin, a method of applying or immersing the curable resin to at least a portion of the end surface of the pre-laminate, followed by curing, can be used. For example, when the insulating member is an insulating tape, a method of attaching the insulating tape to at least a portion of the end surface of the pre-laminate can be used.

[0074] <Electrode laminate formation process> The method of the present disclosure includes (c) laminating a second current collector layer to the second electrode active material layer of the pre-laminate after applying the insulating member to form an electrode laminate.

[0075] The method for forming the electrode laminate by laminating the second current collector layer on the second electrode active material layer of the pre-laminate is not particularly limited. For example, when the second current collector layer is a metal foil, a method of placing the metal foil on the second electrode active material layer of the pre-laminate and pressing the metal foil can be mentioned.

[0076] <Contact process> The method of the present disclosure includes (d) contacting the insulating member with a second current collector layer.

[0077] When the insulating member contains a thermoplastic resin, in step (d), the second current collector layer may be pressed against the insulating member while being heated to adhere it, thereby allowing the second current collector layer to be adhered to the insulating member in a simple manner.

[0078] When the insulating member contains a curable resin that has tackiness after curing, or is an insulating tape that has adhesive properties on both sides, in step (d), the second current collector layer may be pressed against and adhered to the insulating member.

[0079] The method of the present disclosure may include, in step (a), laminating a first electrode active material layer, a solid electrolyte layer, and a second electrode active material layer in this order on both sides of a first current collector layer. In this case, in step (c), a second current collector layer may be laminated on each of the two second electrode active material layers to form an electrode laminate, and in step (d), one of the second current collector layers may be brought into contact with an insulating member.

[0080] Battery module As illustrated in Fig. 4, the battery module 1 of the present disclosure includes the solid-state battery 10 of the present disclosure. In particular, as described above, when the length of the insulating member in the stacking direction of the electrode stack is smaller than the thickness of the electrode stack in the solid-state battery of the present disclosure, the battery module of the present disclosure can prevent the insulating member from interfering with the restraint of the electrode stack in the stacking direction. For the solid-state battery 10 of the present disclosure, reference can be made to the above description of the solid-state battery of the present disclosure.

[0081] The number of solid-state batteries of the present disclosure in the battery module of the present disclosure is not particularly limited and may be at least one. In the battery module of the present disclosure, all batteries may be solid-state batteries of the present disclosure. Note that, although FIG. 4 illustrates an embodiment in which the number of solid-state batteries is two, the number of solid-state batteries in the battery module of the present disclosure is not limited to this.

[0082] 《Solid-state battery》 1, a solid state battery 10 of the present disclosure has an electrode laminate 110. As illustrated in Fig. 3, the electrode laminate 110 has a first current collector layer 111, a first electrode active material layer 112, a solid electrolyte layer 113, a second electrode active material layer 114, and a second current collector layer 115, in this order, and an insulating member 120 is disposed on at least a portion of an end surface of the electrode laminate 110. The insulating member 120 includes a mixture of a resin 121 and an insulating filler 122, and the thermal conductivity of the insulating filler 122 is greater than the thermal conductivity of the resin 121.

[0083] As described above, in a battery including an electrode laminate, the electrode laminate may generate heat during charging and discharging, and in particular, the current collector layer of the electrode laminate is likely to reach a high temperature. The present inventors have discovered that by including an insulating member arranged on an end face of the electrode laminate containing a mixture of a resin and an insulating filler having a thermal conductivity higher than that of the resin, it is possible to dissipate heat generated in the electrode laminate to the outside of the battery via the insulating member.

[0084] In the solid-state battery 10 of the present disclosure, the second current collector layer 115 may extend from the electrode stack 110. In this case, the second current collector layer 115 may be in contact with the insulating member 120, and in particular, the second current collector layer 115 may be adhered to and in contact with the insulating member 120. With this configuration, heat generated in the electrode stack 110 can be dissipated to the outside of the battery via the insulating member 120 and the second current collector 115. [Explanation of symbols]

[0085] 1 Battery Module 10 solid state battery 110 Electrode laminate 111 First current collector layer 112 First electrode active material layer 113 Solid electrolyte layer 114 Second electrode active material layer 115 Second current collector layer 120 Insulating material 130 Laminating Film 140 Current collector terminal

Claims

1. A solid-state battery having an electrode stack, the electrode stack has, in this order, a first current collector layer, a first electrode active material layer, a solid electrolyte layer, a second electrode active material layer, and a second current collector layer; an insulating member is disposed on at least a part of an end surface of the electrode stack; the second current collector layer extends from an end surface of the electrode stack on which the insulating member is disposed, and the second current collector layer is in contact with the insulating member; solid state battery.

2. the electrode stack has the first electrode active material layer, the solid electrolyte layer, the second electrode active material layer, and the second current collector layer, in this order, on both sides of the first current collector layer; and one of the second current collector layers is in contact with the insulating member; The solid-state battery according to claim 1 .

3. the insulating member is disposed on an end surface of the electrode stack, spanning from one of the second electrode active material layers to the other of the second electrode active material layers; and the second current collector layer is in contact with the insulating member over 50% or more of a surface area of ​​the insulating member; The solid-state battery according to claim 2 .

4. The solid-state battery according to claim 1 , wherein the insulating member comprises a thermoplastic resin.

5. The solid-state battery according to claim 1 , wherein the insulating member includes a mixture of a resin and an insulating filler, and the insulating filler has a thermal conductivity greater than that of the resin.

6. The solid-state battery according to claim 5 , wherein the insulating filler is a metal oxide.

7. 7. The solid-state battery according to claim 1, wherein the first current collector layer is a negative electrode current collector layer, the first electrode active material layer is a negative electrode active material layer, the second electrode active material layer is a positive electrode active material layer, and the second current collector layer is a positive electrode current collector layer.

8. A battery module comprising the solid-state battery according to claim 7.

9. A method for producing the solid state battery according to any one of claims 1 to 6, comprising the following steps: (a) forming a preliminary laminate by stacking the first current collector layer, the first electrode active material layer, the solid electrolyte layer, and the second electrode active material layer in this order; (b) applying the insulating member to at least a portion of an end surface of the pre-laminate; (c) after applying the insulating member, laminating the second current collector layer on the second electrode active material layer of the pre-laminate to form the electrode laminate; and (d) contacting the second current collector layer with the insulating member;

10. the insulating member contains a thermoplastic resin, In the step (d), the second current collector layer is pressed against the insulating member while being heated to adhere it to the insulating member.

10. The method of claim 9.

11. A solid-state battery having an electrode stack, the electrode stack has, in this order, a first current collector layer, a first electrode active material layer, a solid electrolyte layer, a second electrode active material layer, and a second current collector layer; an insulating member is disposed on at least a part of an end surface of the electrode stack; The insulating member includes a mixture of a resin and an insulating filler, and The thermal conductivity of the insulating filler is higher than the thermal conductivity of the resin. solid state battery.

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