Battery

Abstract

The invention provides a battery. The battery includes: an electrode body in which a positive electrode current collector, a positive electrode active material, a solid electrolyte, a negative electrode active material, and a negative electrode current collector are laminated; a case that accommodates the electrode body; and an insulating resin layer provided in a gap between the electrode body and the case, the insulating resin layer being provided in a gap between an end surface of the electrode body extending in the longitudinal direction and the case, the insulating resin layer having a thin portion formed at at least one end portion thereof, the thickness of the thin portion in contact with the electrode body is thinner than the central portion of the insulating resin layer.

Description

Technical Field

[0001] This disclosure relates to batteries.

[0002] This application is based on Japanese Patent Application No. 2024-141153, filed on August 22, 2024, and claims priority to it under Section 119 of Title 35 of the United States Code, the disclosure of which is incorporated herein by reference. Background Technology

[0003] Japanese Patent Application Publication No. 5-074424 discloses a secondary battery in which an electrode body is housed in an outer can. In the secondary battery disclosed in Japanese Patent Application Publication No. 5-074424, the electrode body is formed into an oblong shape, and an insulating plate is attached to the bottom of the electrode body, thereby insulating the electrode body from the outer can.

[0004] However, in structures such as those disclosed in Japanese Patent Application Publication No. 5-074424, where the insulating plate is placed at the corner of the outer can to ensure insulation, stress may concentrate at the end of the insulating plate and cause it to peel off when the outer can is deformed by external force. Summary of the Invention

[0005] The purpose of this disclosure is to obtain a battery that can maintain insulation well, taking into account the above facts.

[0006] The battery of the first embodiment includes: an electrode body having a positive current collector, a positive active material, a solid electrolyte, a negative active material, and a negative current collector stacked thereon; a housing housing the electrode body; and an insulating resin layer disposed in the gap between the electrode body and the housing, the insulating resin layer being disposed in the gap between an end face of the electrode body extending in the length direction and the housing, and having a thin-walled portion formed at at least one end of the insulating resin layer, the thickness of the thin-walled portion in contact with the electrode body being thinner than the central portion of the insulating resin layer.

[0007] In the battery of the first embodiment, an electrode body is housed within a casing. The electrode body is constructed by stacking a positive current collector, a positive active material, a solid electrolyte, a negative active material, and a negative current collector. Furthermore, an insulating resin layer is provided in the gap between the electrode body and the casing. Thus, by having the insulating resin layer positioned between the electrode body and the casing, the electrode body is insulated from the casing.

[0008] Here, an insulating resin layer is provided in the gap between the end face of the electrode body extending along the length direction and the housing. Furthermore, a thin-walled portion, thinner than the central portion, is formed at at least one end of the insulating resin layer that contacts the electrode body. Thus, by forming a thin-walled portion at the end of the insulating resin layer, peeling of the insulating resin layer from the housing or the electrode body can be prevented even when an external force is applied to the housing.

[0009] In the second type of battery, the insulating resin layer is formed by including thermally conductive fillers, as in the first type.

[0010] In the second type of battery, the insulating resin layer is thermally conductive because it includes a thermally conductive filler. This allows heat from the electrode body to be released from the casing to the outside via the insulating resin layer. In other words, the cooling performance of the electrode body is improved.

[0011] In the third type of battery, in the first type, a positive electrode tab is provided at one end of the electrode body along its length direction. The positive electrode tab is formed by assembling positive electrode foils extending from the positive current collector. The thin-walled portion is formed at least at the end of the insulating resin layer on the positive electrode tab side.

[0012] In this type of battery, the thin-walled portion of the insulating resin layer is formed at least at the end on the positive electrode tab side. Therefore, insulation can be well maintained even when an external force is applied to the positive electrode tab side of the casing.

[0013] In the fourth type of battery, in the first type, a negative electrode tab is provided at the other end of the electrode body in the length direction. The negative electrode tab is formed by assembling negative electrode foils extending from the negative electrode current collector. The thin-walled portion is formed at least at the end of the insulating resin layer on the negative electrode tab side.

[0014] In the fourth type of battery, a thin-walled portion of the insulating resin layer is formed at least at the end on the negative electrode tab side. Therefore, insulation can be well maintained even when an external force is applied to the negative electrode tab side of the casing.

[0015] In the fifth type of battery, in the first type, the thin-walled portion has a shape in which the thickness gradually decreases from the center of the insulating resin layer toward the end.

[0016] In the fifth type of battery, the thin-walled portion is a shape in which the thickness of the insulating resin layer gradually decreases, thus suppressing stress concentration in a part of the insulating resin layer.

[0017] In the sixth type of battery, in the first type, the thin-walled portion is shaped as a central recess in the thickness direction of the insulating resin layer.

[0018] In the sixth type of battery, a thin-walled portion is formed by recessing the central portion of the insulating resin layer in the thickness direction. As a result, when an external force is applied, a portion of the external force can be absorbed by the recessed central portion.

[0019] In the seventh type of battery, in the first type, the thin-walled portion is formed at both one end and the other end of the insulating resin layer.

[0020] In the seventh type of battery, since thin-walled portions are formed at both ends of the insulating resin layer, the peeling of the insulating resin layer can be suppressed regardless of the direction from which external force is applied.

[0021] In the battery of the eighth type, in any of the first to seventh types, the insulating resin layer is disposed on both sides in the short side direction of the electrode body, and the thin-walled portion is formed only on one side of the insulating resin layer.

[0022] In the battery of the eighth type, insulating resin layers are provided on both sides of the electrode body in the short-side direction, thus insulating the electrode body from the casing on both sides of the short-side direction. Furthermore, the thin-walled portion is formed only on one side of the insulating resin layer. Therefore, by placing the insulating resin layer with the thin-walled portion on the side of the casing where external forces are more easily applied, peeling of the insulating resin layer can be effectively suppressed. On the other hand, by not forming a thin-walled portion in the insulating resin layer on the side where external forces are less likely to apply, insulation performance can be improved.

[0023] As explained above, the battery according to this disclosure can maintain good insulation. Attached Figure Description

[0024] Exemplary embodiments of this disclosure will be described in detail with reference to the following figures, wherein:

[0025] Figure 1 This is a schematic top view showing the main parts of a vehicle using a battery implemented in this way.

[0026] Figure 2 This is a schematic 3D diagram of the battery module.

[0027] Figure 3 This is a schematic cross-sectional view of the battery cell in the embodiment, viewed from the thickness direction.

[0028] Figure 4 This is a schematic cross-sectional view of the battery cell of the first modified example, viewed from the thickness direction.

[0029] Figure 5 This is a schematic cross-sectional view of the battery cell of the second modified example, viewed from the thickness direction.

[0030] Figure 6 It is a schematic enlarged cross-sectional view of the main part of the battery cell of the third variation, viewed from the thickness direction. Detailed Implementation

[0031] (The overall structure of vehicle 100)

[0032] Figure 1 This is a schematic top view showing the main parts of a vehicle 100 using the battery pack 10 of this embodiment. Figure 1 As shown, vehicle 100 is an electric vehicle (BEV) with a battery pack 10 mounted under the floor. Additionally, the arrows UP, FR, and LH in each figure represent the upper side in the vertical direction, the front side in the longitudinal direction, and the left side in the width direction, respectively. When using the directions front-back, left-right, up-down, or forward / backward, unless otherwise specified, they represent the front-back direction, the left-right direction, and the up-down direction, respectively.

[0033] In this embodiment, the vehicle 100 is an example, in which a DC / DC converter 102, an electric compressor 104, and a PTC (Positive Temperature Coefficient) heater 106 are arranged on the front side of the vehicle relative to the battery pack 10. In addition, an electric motor 108, a gearbox 110, an inverter 112, and a charger 114 are arranged on the rear side of the vehicle relative to the battery pack 10.

[0034] The DC current output from the battery pack 10 is regulated by the DC / DC converter 102 and then supplied to the electric compressor 104, PTC heater 106, inverter 112, etc. In addition, by supplying power to the motor 108 via the inverter 112, the rear wheels rotate, thus driving the vehicle 100.

[0035] A charging port 116 is provided on the right side of the rear of the vehicle 100. By connecting the charging port 116 to the charging plug of an external charging device (not shown), power can be stored in the battery pack 10 via the charger 114.

[0036] Furthermore, the configuration and structure of the components constituting the vehicle 100 are not limited to the structure described above. For example, it can also be applied to hybrid vehicles (HV) or plug-in hybrid electric vehicles (PHEVs) equipped with an engine. In this embodiment, the vehicle is a rear-wheel drive vehicle with the electric motor 108 mounted at the rear of the vehicle, but it is not limited to this. It can also be a front-wheel drive vehicle with the electric motor 108 mounted at the front of the vehicle, or a pair of electric motors 108 can be mounted at both the front and rear of the vehicle. Furthermore, it can also be a vehicle with an in-wheel electric motor at each wheel.

[0037] Here, the battery pack 10 is configured to include a plurality of battery modules 11. In this embodiment, as an example, 10 battery modules 11 are provided. Specifically, 5 battery modules 11 are arranged along the front-rear direction on the right side of the vehicle 100, and 5 battery modules 11 are arranged along the front-rear direction on the left side of the vehicle 100. In addition, the battery modules 11 are electrically connected to each other.

[0038] Figure 2 This is a schematic 3D view of battery module 11. (As shown) Figure 2 As shown, the battery module 11 is formed into a generally rectangular parallelepiped shape with the width of the vehicle as its length. Furthermore, the housing 13 of the battery module 11 is made of aluminum alloy. For example, the housing 13 of the battery module 11 is formed by joining aluminum die-castings to both ends of extruded aluminum alloy material using laser welding or the like.

[0039] A pair of voltage terminals 12 and a connector 14 are respectively provided at both ends of the battery module 11 in the vehicle width direction. In addition, busbars (not shown) are welded to both ends of the battery module 11 in the vehicle width direction.

[0040] Here, multiple battery cells serving as batteries are housed inside the battery module 11.

[0041] Figure 3 This is a schematic cross-sectional view of the battery cell 20 of the embodiment, viewed from the thickness direction. (See attached image.) Figure 3 As shown, the battery cell 20 of this embodiment is configured to include an outer can 22 as a housing, an electrode body 24, and a first insulating resin layer 26 and a second insulating resin layer 28 disposed in the gap between the outer can 22 and the electrode body 24.

[0042] The outer can 22 constitutes the outer casing of the battery cell 20 and is formed in a generally rectangular parallelepiped shape. As an example, the outer can 22 in this embodiment is configured to include a generally cylindrical peripheral wall portion 22A, a positive electrode side cover portion 22B that closes the opening on one side of the peripheral wall portion 22A, and a negative electrode side cover portion 22C that closes the opening on the other side of the peripheral wall portion 22A.

[0043] The peripheral wall portion 22A is formed of metal into a generally rectangular cylindrical shape with openings at both ends, and is sized to accommodate the electrode body 24 internally. The positive electrode side cover portion 22B is fixed to the opening on one side of the peripheral wall portion 22A by fitting, welding, or other means, closing the opening on one side of the peripheral wall portion 22A. Furthermore, an opening 22D is formed in the center of the positive electrode side cover portion 22B, and a generally frame-shaped positive electrode side insulator 30 is disposed in this opening 22D. A positive electrode tab 34, described later, is disposed inside the positive electrode side insulator 30.

[0044] The negative electrode side cover 22C is fixed to the opening on the other side of the peripheral wall 22A by fitting, welding or other means, thus closing the opening on the other side of the peripheral wall 22A. Furthermore, an opening 22E is formed in the center of the negative electrode side cover 22C, and a generally frame-shaped negative electrode side insulator 32 is disposed in this opening 22E. A negative electrode tab 36, described later, is disposed inside the negative electrode side insulator 32.

[0045] The electrode body 24 housed in the outer container 22 is constructed by stacking a positive current collector, a positive active material, a solid electrolyte, a negative active material, and a negative current collector. Furthermore, the electrode body 24 has an external shape corresponding to the outer container 22, and when viewed from the stacking direction, it is formed into a generally rectangular shape having both a long side and a short side. Additionally, the electrode body 24 of this embodiment... Figure 3 The depth direction of the paper surface is the stacking direction. In addition, the left-right direction of the paper surface of electrode body 24 is the long side direction, and the up-down direction of the paper surface is the short side direction.

[0046] Both the positive and negative current collectors are formed of metal foil, such as aluminum foil, copper foil, nickel foil, titanium foil, and stainless steel foil. Furthermore, a coating layer can be formed on the surface of the current collector, which can be formed by known methods such as plating or spraying. Aluminum foil is preferred as the positive current collector, and copper foil is preferred as the negative current collector.

[0047] There are no particular limitations on the positive electrode active material; previously known materials can be appropriately used. For example, LiCoO2, LiNiO2, LiMnO2, LiMn2O4, Li(NiCoMn)O2, Li(NiCoAl)O2, and LiFePO4 can be cited as positive electrode active materials. Furthermore, the positive electrode active material particles can be Hi-Nickel (positive electrode active materials with a high Ni ratio), or they can be Li-Ni-Co-Mn composite oxides or ternary positive electrode active materials.

[0048] Examples of anode active materials include natural graphite, artificial graphite, hard carbon (non-graphitized carbon) or soft carbon (graphitizable carbon), Si, SiOx (0 < x < 2), Si-based alloys, Sn, SnOx (0 < x < 2), Li, Li-based alloys, and Li4Ti5O. 12 At least one of the group. Examples of artificial graphite include highly oriented graphite and mesophase carbon microspheres. Artificial graphite is preferred as the negative electrode active material.

[0049] Here, the positive electrode foil extends to one side from the end of the positive current collector, and the positive electrode foils of multiple stacked positive current collectors are assembled to form the positive electrode tab 34. The positive electrode tab 34 extends outward from the inside of the positive electrode side insulator 30 to the outside of the outer can 22.

[0050] On the other hand, the negative electrode foil extends from one end of the negative electrode current collector to the other side, and the negative electrode foils of multiple stacked negative electrode current collectors are assembled to form the negative electrode tab 36. The negative electrode tab 36 extends from the inside of the negative electrode side insulator 32 to the outside of the outer packaging can 22. Thus, in the battery cell 20 of this embodiment, a positive electrode tab 34 is provided at one end of the electrode body 24 in the longitudinal direction, and a negative electrode tab 36 is provided at the other end in the longitudinal direction.

[0051] A first insulating resin layer 26 and a second insulating resin layer 28 are provided in the gap between the electrode body 24 and the outer can 22.

[0052] The first insulating resin layer 26 is disposed in the gap between the end face of the electrode body 24 on one side in the short side direction and the outer can 22, and is bonded to at least one of the electrode body 24 and the outer can 22. In other words, the first insulating resin layer 26 is disposed in the gap between the end face of the electrode body 24 extending in the length direction and the outer can 22.

[0053] In this embodiment, as an example, the first insulating resin layer 26 is bonded to both the electrode body 24 and the outer can 22. Furthermore, the first insulating resin layer 26 is bonded to the entire area of ​​the end face of one end of the electrode body 24 in the short side direction, covering the entire end face.

[0054] Furthermore, the first insulating resin layer 26 of this embodiment is formed by including a thermally conductive filler. Therefore, the first insulating resin layer 26 has thermal conductivity. In addition to the thermally conductive filler, the first insulating resin layer 26 also includes a known insulating resin with insulating properties. Furthermore, metals, synthetic diamonds, silicon carbide, etc., are used as the thermally conductive filler.

[0055] Here, a thin-walled portion is formed at at least one end of the first insulating resin layer 26. In this embodiment, thin-walled portions 26A are formed at one end and the other end along the length of the first insulating resin layer 26.

[0056] The thin-walled portion 26A is formed such that the thickness in contact with the electrode body 24 is thinner than the central portion of the first insulating resin layer 26. Specifically, the thin-walled portion 26A has a shape in which the thickness gradually decreases from the central portion of the first insulating resin layer 26 toward the end. Therefore, viewed from the stacking direction of the electrode body 24, the thickness of the first insulating resin layer 26 in the thin-walled portion 26A gradually decreases from the central side of the length direction of the electrode body 24 toward the end side.

[0057] In this embodiment, as described above, by forming thin-walled portions 26A at both ends of the first insulating resin layer 26, spaces unfilled by the first insulating resin layer 26 are provided at both corners of the outer packaging can 22.

[0058] On the other hand, the second insulating resin layer 28 is disposed in the gap between the end face of the electrode body 24 on the other side in the short side direction and the outer packaging can 22, and is bonded to at least one of the electrode body 24 and the outer packaging can 22. In other words, the second insulating resin layer 28 is disposed in the gap between the end face of the electrode body 24 extending in the length direction and the outer packaging can 22.

[0059] In this embodiment, as an example, the second insulating resin layer 28 is bonded to both the electrode body 24 and the outer packaging can 22. Furthermore, the second insulating resin layer 28 is bonded to the entire area of ​​the end face of one end of the electrode body 24 in the short side direction, covering the entire end face.

[0060] Furthermore, in this embodiment, the second insulating resin layer 28, like the first insulating resin layer 26, is also composed of thermally conductive filler. Additionally, the first insulating resin layer 26 and the second insulating resin layer 28 may be formed to be longer than the electrode body 24.

[0061] In this embodiment, the second insulating resin layer 28 differs from the first insulating resin layer 26 in that it does not have a thin-walled portion. Therefore, the thin-walled portion is formed only in one insulating resin layer.

[0062] (effect)

[0063] Next, the function of the battery cell 20 and the energy storage device mounting structure in this embodiment will be explained.

[0064] In the battery cell 20 of this embodiment, an electrode body 24 is housed in an outer casing 22, which serves as the outer shell. The electrode body 24 is constructed by stacking a positive current collector, a positive active material, a solid electrolyte, a negative active material, and a negative current collector. Furthermore, a first insulating resin layer 26 and a second insulating resin layer 28 are provided in the gap between the electrode body 24 and the outer casing 22. Thus, by having the insulating resin layer positioned between the electrode body 24 and the outer casing 22, the electrode body 24 is insulated from the outer casing 22.

[0065] Here, a first insulating resin layer 26 is disposed in the gap between the end face of the electrode body 24 extending along the length direction and the outer can 22. A thin-walled portion 26A, which is thinner than the central portion and contacts the electrode body 24, is formed at at least one end of the first insulating resin layer 26. In this way, by forming a thin-walled portion 26A at the end of the first insulating resin layer 26, even when an external force is applied to the outer can 22, the first insulating resin layer 26 can be prevented from peeling off from the outer can 22 or the electrode body 24. As a result, good insulation can be maintained.

[0066] Furthermore, in this embodiment, since the first insulating resin layer 26 and the second insulating resin layer 28 include thermally conductive fillers, they are thermally conductive. Therefore, heat from the electrode body 24 can be released from the outer canister 22 to the outside via the first insulating resin layer 26 and the second insulating resin layer 28. In other words, the cooling performance of the electrode body 24 can be improved.

[0067] Furthermore, in this embodiment, since the thin-walled portion 26A of the first insulating resin layer 26 is formed at the end on the positive electrode tab 34 side, insulation can be well maintained even when an external force is applied to the positive electrode tab 34 side of the outer packaging can 22. Similarly, the thin-walled portion 26A is also formed at the end on the negative electrode tab 36 side. Thus, insulation can be well maintained even when an external force is applied to the negative electrode tab 36 side of the outer packaging can 22.

[0068] Furthermore, the thin-walled portion 26A has a shape in which the thickness of the first insulating resin layer 26 gradually decreases, thus suppressing stress concentration on a portion of the first insulating resin layer 26. In particular, in this embodiment, since the thin-walled portion 26A is formed at both ends of the first insulating resin layer 26, stress concentration can be suppressed regardless of the direction from which external force is applied, thereby suppressing the peeling of the first insulating resin layer 26.

[0069] Furthermore, in this embodiment, insulating resin layers (first insulating resin layer 26 and second insulating resin layer 28) are provided on both sides of the short side of the electrode body 24, thus insulating the electrode body 24 from the outer can 22 on both sides of the short side. Additionally, the thin-walled portion 26A is formed only in the first insulating resin layer 26; therefore, by providing the first insulating resin layer 26 with the thin-walled portion 26A on the side of the outer can 22 where external force is easily applied, peeling of the first insulating resin layer 26 can be effectively suppressed. On the other hand, by not forming a thin-walled portion in the second insulating resin layer 28 on the side where external force is less likely to apply, insulation performance can be improved.

[0070] Furthermore, in this embodiment, thin-walled portions 26A with gradually decreasing thickness are provided at both ends of the first insulating resin layer 26, but this is not a limitation. For example, alternative methods may also be used. Figure 4 The first variant shown Figure 5 The second variation shown and Figure 6 The structure described in the third variation shown is illustrated. In the first to third variations described below, the same reference numerals are used to refer to structures that are the same as those in the embodiment, and descriptions are omitted where appropriate.

[0071] (First variation)

[0072] Figure 4 This is a schematic cross-sectional view of the battery cell 40 of the first modified example, viewed from the thickness direction. Figure 4 As shown, in this modified example, an electrode body 24 is housed in the outer can 22, and insulating resin layers are provided on both sides of the electrode body 24 in the short side direction.

[0073] Specifically, a first insulating resin layer 42 is provided on one end of the electrode body 24 in the short side direction (the side above the paper), and a second insulating resin layer 28 is provided on the other end of the electrode body 24 in the short side direction (the side below the paper). The second insulating resin layer 28 has the same structure as in the embodiment.

[0074] The first insulating resin layer 42 is disposed in the gap between the end face of the electrode body 24 on one side in the short side direction and the outer packaging can 22, and is bonded to at least one of the electrode body 24 and the outer packaging can 22. In other words, the first insulating resin layer 42 is disposed in the gap between the end face of the electrode body 24 extending in the length direction and the outer packaging can 22.

[0075] In addition, the first insulating resin layer 42 is bonded to both the electrode body 24 and the outer can 22, and is bonded to the entire area of ​​the end face of one end in the short side direction of the electrode body 24, thus covering the entire end face.

[0076] Furthermore, the first insulating resin layer 42 is formed by including a thermally conductive filler. Therefore, the first insulating resin layer 42 is thermally conductive. In addition to the thermally conductive filler, the first insulating resin layer 42 also includes a known insulating resin with insulating properties.

[0077] In this modified example, a thin-walled portion 42A is formed at one end of the first insulating resin layer 42. Specifically, the thin-walled portion 42A is formed at the end of the first insulating resin layer 42 on the side of the positive electrode tab 34. However, the structure differs from the embodiment in that no thin-walled portion is formed at the other end of the first insulating resin layer 42.

[0078] In the battery cell 40 of this modified example, a thin-walled portion 42A is formed at the end of the first insulating resin layer 42 on the positive electrode tab 34 side. As a result, insulation can be well maintained even when an external force is applied to the positive electrode tab 34 side of the external packaging can 22.

[0079] Furthermore, when the heat generation on the positive and negative sides of the electrode body 24 differs, especially when the heat generation on the positive side is greater, forming a thin-walled portion 42A on the positive side reduces the heat dissipation on the positive side compared to not forming the thin-walled portion 42A. As a result, a balance can be achieved between the heat dissipation of residual heat generated from the outer casing 22 on the positive and negative sides.

[0080] (Second variation)

[0081] Figure 5 This is a schematic cross-sectional view of the battery cell 50 of the second modified example, viewed from the thickness direction. Figure 5 As shown, in this modified example, an electrode body 24 is housed in the outer can 22, and insulating resin layers are provided on both sides of the electrode body 24 in the short side direction.

[0082] Specifically, a first insulating resin layer 52 is provided on one end of the electrode body 24 in the short side direction (the side above the paper), and a second insulating resin layer 28 is provided on the other end of the electrode body 24 in the short side direction (the side below the paper). The second insulating resin layer 28 has the same structure as in the embodiment.

[0083] The first insulating resin layer 52 is disposed in the gap between the end face of the electrode body 24 on one side in the short side direction and the outer packaging can 22, and is bonded to at least one of the electrode body 24 and the outer packaging can 22. In other words, the first insulating resin layer 52 is disposed in the gap between the end face of the electrode body 24 extending in the length direction and the outer packaging can 22.

[0084] In addition, the first insulating resin layer 52 is bonded to both the electrode body 24 and the outer can 22, and is bonded to the entire area of ​​the end face of one end in the short side direction of the electrode body 24, thus covering the entire end face.

[0085] Furthermore, the first insulating resin layer 52 is formed by including a thermally conductive filler. Therefore, the first insulating resin layer 52 is thermally conductive. In addition to the thermally conductive filler, the first insulating resin layer 52 also includes a known insulating resin with insulating properties.

[0086] In this modified example, a thin-walled portion 52A is formed at the other end of the first insulating resin layer 52. Specifically, the thin-walled portion 52A is formed at the end on the negative electrode tab 36 side of the first insulating resin layer 52. Furthermore, the structure differs from the embodiment in that a thin-walled portion is not formed at one end of the first insulating resin layer 52.

[0087] In the battery cell 50 of this modified example, a thin-walled portion 52A is formed at the end of the negative electrode tab 36 side in the first insulating resin layer 52. As a result, insulation can be well maintained even when an external force is applied to the negative electrode tab 36 side of the external packaging can 22.

[0088] Furthermore, when the heat generation on the positive and negative sides of the electrode body 24 is different, especially when the heat generation on the positive side is large, by forming a thin-walled portion 52A on the negative side and not forming a thin-walled portion 52A on the positive side, residual heat can be actively generated from the positive side, which is prone to heat generation, and the temperature rise of the electrode body 24 can be suppressed.

[0089] (Third variation)

[0090] Figure 6 This is a schematic enlarged cross-sectional view of the main part of the battery cell 60 in the third modified example, viewed from the thickness direction. Figure 6 As shown, in this modified example, the electrode body 24 is housed in the outer can 22. Furthermore, similar to the battery cell 20 in the embodiment, insulating resin layers are provided on both sides of the electrode body 24 in the short-side direction.

[0091] Specifically, a first insulating resin layer 62 is provided on one end of the electrode body 24 in the short-side direction (the side above the paper). The first insulating resin layer 62 is disposed in the gap between the end face of the electrode body 24 in the short-side direction and the outer packaging can 22, and is bonded to at least one of the electrode body 24 and the outer packaging can 22. In other words, the first insulating resin layer 62 is disposed in the gap between the end face of the electrode body 24 extending in the length direction and the outer packaging can 22. In addition, the first insulating resin layer 62 is composed of thermally conductive filler.

[0092] Here, thin-walled portions 62A are formed at one end and the other end of the first insulating resin layer 62. The thin-walled portions 62A differ from those in the embodiment in that the central portion in the thickness direction of the first insulating resin layer 62 is recessed.

[0093] In the first insulating resin layer 62, the thin-walled portion 62A formed on the positive electrode tab 34 side has a shape in which the central portion of the first insulating resin layer 62 in the thickness direction is recessed towards the negative electrode tab 36 side. In addition, in the thin-walled portion 62A, one end in the thickness direction is bonded to the end of the electrode body 24, and the other end in the thickness direction is bonded to the outer packaging can 22.

[0094] In the first insulating resin layer 62, the thin-walled portion 62A formed on the negative electrode tab 36 side has a shape in which the central portion of the first insulating resin layer 62 in the thickness direction is recessed towards the positive electrode tab 34 side. In addition, in the thin-walled portion 62A, one end in the thickness direction is bonded to the end of the electrode body 24, and the other end in the thickness direction is bonded to the outer packaging can 22.

[0095] In the battery cell 60 of this modified example, a thin-walled portion 62A is formed by recessing the central portion of the first insulating resin layer 62 in the thickness direction. As a result, when an external force is applied, a portion of the external force can be absorbed by the recessed central portion.

[0096] The battery cells 20, 40, 50, and 60 involved in the embodiments and variations have been described above, but are not limited thereto. It is natural that they can be implemented in various ways without departing from the spirit of this disclosure. For example, in the above embodiments, the battery cells 20, 40, 50, and 60 are described in detail. Figure 2The battery module 11 shown is described as housing multiple battery cells 20, but it is not limited to this. A structure in which the battery cells 20 are directly mounted on the vehicle body is also possible.

[0097] Furthermore, in the above embodiments, such as Figure 3 As shown, a thin-walled portion 26A is formed only on one side of the first insulating resin layer 26 disposed in the short side direction of the electrode body 24, but it is not limited to this. For example, a thin-walled portion may also be formed on the second insulating resin layer 28 disposed on the other side of the short side direction of the electrode body 24.

[0098] Furthermore, it may be configured without the second insulating resin layer 28. In this case, an insulating component may be disposed between the electrode body 24 and the outer canister 22 instead of the second insulating resin layer 28.

[0099] Furthermore, in the above embodiments, the first insulating resin layer 26 and the second insulating resin layer 28 are configured to include thermally conductive fillers, but are not limited thereto, and may also be configured to not include thermally conductive fillers. However, in terms of improving the cooling performance of the electrode body 24, it is preferable to use an insulating resin layer including thermally conductive fillers.

[0100] Regarding the above-described embodiments, the following notes are disclosed.

[0101] (Note 1)

[0102] A battery comprising: an electrode body having a positive current collector, a positive active material, a solid electrolyte, a negative active material, and a negative current collector stacked thereon; a housing housing the electrode body; and an insulating resin layer disposed in the gap between the electrode body and the housing, the insulating resin layer being disposed in the gap between an end face of the electrode body extending along its length and the housing, and having a thin-walled portion formed at at least one end of the insulating resin layer, the thickness of the thin-walled portion in contact with the electrode body being thinner than the central portion of the insulating resin layer.

[0103] (Note 2)

[0104] According to the battery described in Appendix 1, the insulating resin layer is composed of thermally conductive fillers.

[0105] (Note 3)

[0106] According to Appendix 1 or 2, a positive electrode tab is provided at one end of the long side of the electrode body, the positive electrode tab is formed by assembling a positive electrode foil extending from the positive current collector, and the thin-walled portion is formed at least at the end of the insulating resin layer on the positive electrode tab side.

[0107] (Note 4)

[0108] According to Appendix 1 or 2, a negative electrode tab is provided at the other end of the electrode body in the longitudinal direction. The negative electrode tab is formed by assembling a negative electrode foil extending from the negative electrode current collector. The thin-walled portion is formed at least at the end of the insulating resin layer on the negative electrode tab side.

[0109] (Note 5)

[0110] According to any one of Appendices 1 to 4, the thin-walled portion has a shape in which the thickness gradually decreases from the center of the insulating resin layer toward the end.

[0111] (Note 6)

[0112] According to any one of Appendices 1 to 4, the thin-walled portion has a shape in which the central portion of the insulating resin layer is recessed in the thickness direction.

[0113] (Note 7)

[0114] According to any one of Appendices 1 to 6, the thin-walled portion is formed at both one end and the other end of the insulating resin layer.

[0115] (Note 8)

[0116] According to any one of Appendices 1 to 7, the insulating resin layer is disposed on both sides of the electrode body in the short side direction, and the thin-walled portion is formed only on one side of the insulating resin layer.

Claims

1. A battery having: The electrode body comprises a positive current collector, a positive active material, a solid electrolyte, a negative active material, and a negative current collector, all stacked together. Housing, housing the electrode body; and An insulating resin layer is disposed in the gap between the electrode body and the housing. The insulating resin layer is disposed in the gap between the end face of the electrode body extending along the length direction and the housing, and a thin-walled portion is formed at at least one end of the insulating resin layer, wherein the thickness of the thin-walled portion in contact with the electrode body is thinner than that of the central portion of the insulating resin layer.

2. The battery according to claim 1, wherein, The insulating resin layer is composed of thermally conductive fillers.

3. The battery according to claim 1, wherein, A positive electrode tab is provided at one end along the length of the electrode body. The positive electrode tab is formed by assembling the positive electrode foil extending from the positive current collector. The thin-walled portion is formed at least at the end of the insulating resin layer on the positive electrode tab side.

4. The battery according to claim 1, wherein, A negative electrode tab is provided at the other end of the electrode body along its length. The negative electrode tab is formed by assembling the negative electrode foil extending from the negative electrode current collector. The thin-walled portion is formed at least at the end of the insulating resin layer on the negative electrode tab side.

5. The battery according to claim 1, wherein, The thin-walled portion has a shape in which the thickness gradually decreases from the center of the insulating resin layer toward the ends.

6. The battery according to claim 1, wherein, The thin-walled portion has a central recessed shape in the thickness direction of the insulating resin layer.

7. The battery according to claim 1, wherein, The thin-walled portion is formed at both one end and the other end of the insulating resin layer.

8. The battery according to any one of claims 1 to 7, wherein, The insulating resin layer is disposed on both sides of the short side of the electrode body. The thin-walled portion is formed only on one side of the insulating resin layer.

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