Battery cell and battery module

Abstract

The invention relates to a battery cell and a battery module. A battery cell having: an electrode body in which a plurality of laminated structures having a positive electrode, a negative electrode, and a separator interposed between the positive electrode and the negative electrode are further laminated; and a battery cell case in which the electrode body is sealed, in which at least one of the current collector of the positive electrode and the current collector of the negative electrode has an uncoated part in which the composite material is not coated at the peripheral edge of the surface. Among the current collectors having the uncoated portions, the uncoated portion of the current collector having the largest distance from the surface of the battery cell case is used as a first uncoated portion, and the first uncoated portion extends to the outside of the battery cell case and is provided with a first exposed portion.

Description

Technical Field

[0001] The present disclosure relates to a battery cell and a battery module. Background Art

[0002] Conventionally, a battery cell is used in which an electrode body in which a plurality of positive electrodes, negative electrodes, and separators are stacked is sealed in a battery cell case.

[0003] For example, Japanese Patent Publication No. 2015-522912 discloses a battery cell in which a member for dissipating heat generated from an electrode body (for example, heat generated during charge / discharge or when a short circuit occurs) is installed inside the electrode body, and a portion of the heat dissipating member is exposed to the outside.

[0004] International Publication No. 2013 / 027306 discloses a battery cell having a structure in which a current collector disposed near a battery cell case extends to the outside. Summary of the invention

[0005] Problem that the invention aims to solve

[0006] In the battery cell disclosed in Japanese Patent Publication No. 2015-522912, a heat dissipation member is exposed to the outside of the battery cell to dissipate heat generated from the electrode body. In addition, in International Publication No. 2013 / 027306, a current collector is extended to the outside of the battery cell to dissipate heat from the electrode body.

[0007] However, there is a need for a configuration that can dissipate heat more efficiently.

[0008] The present disclosure has been made in view of the above-mentioned actual situation, and an object of the present disclosure is to provide a battery cell capable of efficiently dissipating heat generated from an electrode body, and a battery module including the battery cell.

[0009] Solutions for solving problems

[0010] The aspects of the present disclosure include the following aspects.

[0011] <1>

[0012] A battery cell, the battery cell comprising:

[0013] an electrode body further including a plurality of stacked structures, the stacked structures having a positive electrode, a negative electrode, and a separator interposed between the positive electrode and the negative electrode; and

[0014] The battery cell casing has the electrode body enclosed therein, wherein:

[0015] The positive electrode and the negative electrode each include a current collector and a composite material containing an active material and coated on a surface of the current collector.

[0016] At least one of the current collector of the positive electrode and the current collector of the negative electrode has an uncoated portion on the peripheral edge of the surface where the composite material is not coated,

[0017] Among the current collectors having the uncoated portions, the uncoated portion of the current collector that is the longest in distance from the surface of the cell case is defined as a first uncoated portion that extends to the outside of the cell case and includes a first exposed portion.

[0018] <2>

[0019] according to <1> In the battery cell, the electrode surface of the electrode body has a rectangular shape, and the first exposed portion is arranged on a long side of the rectangular shape.

[0020] <3>

[0021] according to <1> or <2> In the battery cell, the electrode surface of the electrode body has a rectangular shape, and the electrode of the positive electrode and the negative electrode having a longer side of the rectangular shape has the first exposed portion.

[0022] <4>

[0023] according to <1> ~ <3> A battery cell as described in any one of the preceding claims, wherein the uncoated portion of the collector having a smaller distance from the surface of the battery cell case than the collector having the first uncoated portion is used as a second uncoated portion, and the second uncoated portion extends to the outside of the battery cell case and has a second exposed portion.

[0024] <5>

[0025] according to <4> The battery cell may include a portion where the first uncoated portion and the second uncoated portion are joined inside the battery cell case.

[0026] <6>

[0027] according to <4> or <5> In the battery cell, the first uncoated portion has a plate thickness greater than that of the second uncoated portion.

[0028] <7>

[0029] A battery module comprising:

[0030] <1> ~ <6> The battery cell described in any one of the preceding claims; and

[0031] at least one of a cooler and a battery module housing, wherein

[0032] The first exposed portion is insulated and joined to at least one of the cooler and the battery module case.

[0033] Effects of the Invention

[0034] According to the present disclosure, it is possible to provide a battery cell capable of efficiently dissipating heat generated from an electrode body, and a battery module including the battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a schematic cross-sectional view illustrating a battery cell according to an embodiment of the present disclosure.

[0036] Figure 2 It is a schematic perspective view showing an electrode body of a battery cell according to an embodiment of the present disclosure.

[0037] Figure 3 This is a schematic cross-sectional view illustrating another form of the battery cell according to the embodiment of the present disclosure.

[0038] Figure 4 It is a schematic plan view showing the main parts of the vehicle.

[0039] Figure 5 This is a schematic perspective view of a battery module.

[0040] Figure 6 It is a top view of the battery module with the upper cover removed.

[0041] Figure 7 This is a schematic diagram of battery cells housed in a battery module as viewed from the thickness direction.

[0042] Description of Reference Numerals

[0043] 4: positive electrode, 42, 420: positive electrode collector, 42A: second exposed portion, 44: positive electrode composite material, 5: negative electrode, 52, 520: negative electrode collector, 52A: first exposed portion, 54: negative electrode composite material, 6: separator, 7: battery cell case, 8: electrode body, 10: battery pack, 11: battery module, 12: voltage terminal, 14: connector, 20: battery cell, 22: flexible printed substrate, 24: thermistor, 26: terminal, 28: laminating film, 30: fixing belt, 100: vehicle, 102: converter, 104: electric compressor, 106: heater, 108: motor, 110: gear box, 112: inverter, 114: on-board charger, 116: charging port. DETAILED DESCRIPTION

[0044] <Battery Unit>

[0045] The battery cell of the embodiment of the present disclosure has an electrode body and a battery cell shell, wherein the electrode body is further stacked with a plurality of stacked structures, wherein the stacked structures have a positive electrode, a negative electrode, and a separator between the positive electrode and the negative electrode, and the battery cell shell has the electrode body enclosed inside. The positive electrode and the negative electrode respectively have a collector and a composite material containing an active material and applied to the surface of the collector. Furthermore, at least one of the collector of the positive electrode and the collector of the negative electrode has an uncoated portion on the peripheral portion of the surface where the composite material is not applied.

[0046] Furthermore, the uncoated portion of the current collector having the uncoated portion, which is the longest distance from the surface of the battery cell case, is defined as the first uncoated portion, and the first uncoated portion extends to the outside of the battery cell case and has a first exposed portion. It should be noted that, among the current collectors having the uncoated portion, the current collector having the longest distance from the surface of the battery cell case refers to, for example, the current collector closest to the center of the electrode body in the stacking direction of the electrode body among the stacked electrode bodies.

[0047] Hereinafter, one embodiment of a battery cell according to an embodiment of the present disclosure will be described using the drawings.

[0048] Each figure described below is a schematic diagram, and the size and shape of each part are appropriately exaggerated for easy understanding. In addition, the same reference numerals are attached to corresponding parts in each figure, and repeated descriptions are appropriately omitted.

[0049] Figure 1 It is a schematic cross-sectional view illustrating a battery cell according to an embodiment of the present disclosure.

[0050] Figure 1 The battery cell 20 shown has a positive electrode 4, a negative electrode 5, and a separator 6 between the positive electrode 4 and the negative electrode 5. Furthermore, a stacked structure of a plurality of positive electrodes 4, negative electrodes 5, and separators 6 is further stacked to form an electrode body 8. The positive electrode 4 has a positive electrode collector 42 and a positive electrode composite material 44 containing an active material and coated on the surface of the positive electrode collector 42, and the negative electrode 5 has a negative electrode collector 52 and a negative electrode composite material 54 containing an active material and coated on the surface of the negative electrode collector 52. It should be noted that in Figure 1 In the electrode body 8 shown, next to the structure in which the positive electrode 4, the separator 6, and the negative electrode 5 are stacked in this order, there is a structure in which the negative electrode 5, the separator 6, and the positive electrode 4 are stacked in this order, that is, the negative electrodes 5 are adjacent to each other, and the adjacent negative electrodes 5 share a negative electrode collector 52. Similarly, next to the structure in which the negative electrode 5, the separator 6, and the positive electrode 4 are stacked in this order, there is a structure in which the positive electrode 4, the separator 6, and the negative electrode 5 are stacked in this order, that is, the positive electrodes 4 are adjacent to each other, and the adjacent positive electrodes 4 share a positive electrode collector 42. Thus, Figure 1The electrode body 8 shown is stacked in sequence from the top with "positive electrode collector 42, positive electrode composite material 44, separator 6, negative electrode composite material 54, negative electrode collector 52, negative electrode composite material 54, separator 6, positive electrode composite material 44, positive electrode collector 42, positive electrode composite material 44, separator 6, negative electrode composite material 54, negative electrode collector 52, negative electrode composite material 54...positive electrode collector 42".

[0051] The battery cell 20 includes a battery cell case 7 that seals an electrode body 8. The battery cell case 7 is formed by welding the ends of two films together to form a housing portion that seals the electrode body 8.

[0052] The positive electrode current collector 42 of the positive electrode 4 has an uncoated portion on the peripheral portion of the surface where the positive electrode composite material 44 is not coated. Similarly, the negative electrode current collector 52 of the negative electrode 5 has an uncoated portion on the peripheral portion of the surface where the negative electrode composite material 54 is not coated. Moreover, among the current collectors having uncoated portions, the uncoated portion (referred to as "first uncoated portion") 52B of the negative electrode current collector 520, which corresponds to the current collector with the largest distance from the surface of the battery cell case 7, extends to the outside of the battery cell case 7 and has a first exposed portion 52A exposed from the battery cell case 7. That is, the first uncoated portion 52B of the negative electrode current collector 520 continues to the first exposed portion 52A disposed outside the battery cell case 7. The top end of the first exposed portion 52A is formed in a curved shape.

[0053] The negative electrode current collector 520 having the first exposed portion 52A is located in the stacking direction ( Figure 1 The collector closest to the center of the electrode body 8 in the direction of the arrow X in FIG.

[0054] The battery cell according to the embodiment of the present disclosure has the above-described structure, and can efficiently dissipate the heat generated from the electrode body.

[0055] In the electrode body, heat is generated during charging and discharging, short circuiting, etc. In order to dissipate the heat generated from the electrode body, in the past, for example, a structure was adopted in which the heat generated from the electrode body was dissipated by exposing the heat dissipation component to the outside of the battery cell, or by extending the collector closest to the surface of the battery cell shell to the outside of the battery cell to form a path for dissipating the heat from the electrode body. However, in the former, due to the bonding state between the electrode body and the heat dissipation component, heat conduction at the bonding portion may become a rate-limiting process. In addition, in the latter, in the stacked electrode body, the heat dissipation path from the center may become a rate-limiting process. Therefore, it is necessary to dissipate the heat generated from the electrode body more efficiently.

[0056] In contrast, the battery cell of the embodiment of the present disclosure adopts a structure in which a collector having an uncoated portion is provided in the electrode body housed in the battery cell, and the collector having the uncoated portion which is farthest from the surface of the battery cell housing is also used as a heat dissipation member. Therefore, in the electrode body which is a heat source, the collector arranged in the center part which is particularly prone to heat accumulation is used as a heat dissipation member. As a result, heat can be dissipated smoothly without the speed-limiting process of heat conduction, and the heat generated from the electrode body can be dissipated efficiently.

[0057] In addition, no dedicated additional member for heat dissipation is used, thereby achieving a reduction in the number of parts.

[0058] · Location of the first exposed part

[0059] When the shape of the electrode surface of the electrode body is a rectangle, the first exposed portion is preferably arranged on the long side of the rectangle.

[0060] That is, Figure 2 As shown, when the electrode body 8 is in a substantially rectangular shape and the electrode surface 8A is in a rectangular shape, the first exposed portion 52A in the current collector 520 is preferably disposed on the long side surface 8B rather than the short side surface 8C of the rectangular shape of the electrode surface 8A. Figure 2 In the figure, the positive electrode collector, positive electrode composite material, negative electrode collector, negative electrode composite material, separator, etc. constituting the electrode body 8 are omitted, and the electrode body is depicted only as the electrode body 8 except for the collector 520 having the first exposed portion 52A.

[0061] With this structure, the distance between the center of the electrode body where heat is easily concentrated and the first exposed portion can be shortened, and the cross-sectional area of ​​the heat dissipation path can be increased, so that the heat generated from the electrode body can be dissipated more efficiently.

[0062] ·Electrode for the first exposed part is provided

[0063] When the shape of the electrode surface of the electrode body is a rectangle, the first exposed portion is preferably provided on the electrode with the longer long side of the rectangular shape of the positive electrode and the negative electrode. Thus, the cross-sectional area of ​​the heat dissipation path can be increased, so that the heat generated from the electrode body can be dissipated more efficiently. It should be noted that the electrode with the longer long side of the rectangular shape of the positive electrode and the negative electrode is preferably the negative electrode.

[0064] · Part 2

[0065] exist Figure 1 , an embodiment is shown in which the uncoated portion of the current collector has only one exposed portion extending to the outside of the battery cell case, but the present invention is not limited thereto and may have two or more exposed portions.

[0066] Here, use Figure 3 A method having two exposed portions will be described.

[0067] Figure 3 This is a schematic cross-sectional view illustrating another form of the battery cell according to the embodiment of the present disclosure.

[0068] for Figure 3 In the battery cell 20 shown in the figure, among the current collectors having uncoated portions, the first uncoated portion 52B of the negative electrode current collector 520, which corresponds to the current collector having the largest distance from the surface of the battery cell case 7, extends to the outside of the battery cell case 7 and has a first exposed portion 52A exposed from the battery cell case 7. In addition, the uncoated portion (referred to as "second uncoated portion") 42B of the positive electrode current collector 420 having a smaller distance from the surface of the battery cell case 7 than the negative electrode current collector 520 having the first exposed portion 52A extends to the outside of the battery cell case 7 and has a second exposed portion 42A. That is, the first uncoated portion 52B of the negative electrode current collector 520 continues to the first exposed portion 52A disposed outside the battery cell case 7, and the second uncoated portion 42B of the positive electrode current collector 420 continues to the second exposed portion 42A disposed outside the battery cell case 7. The top ends of the first exposed portion 52A and the second exposed portion 42A are both formed in a curved shape.

[0069] The negative electrode current collector 520 having the first exposed portion 52A is the current collector closest to the center of the electrode body 8 in the stacking direction of the electrode body 8, and the positive electrode current collector 420 having the second exposed portion 42A is the current collector farther from the center of the electrode body 8 than the negative electrode current collector 520 in the stacking direction of the electrode body 8.

[0070] With this structure, the cross-sectional area of ​​the heat dissipation path can be increased, so the heat generated from the electrode body can be dissipated more efficiently.

[0071] It should be noted that the second uncoated portion is preferably joined to the first uncoated portion inside the battery cell case. Providing a portion where the first uncoated portion and the second uncoated portion are joined inside the battery cell case can efficiently dissipate heat from the entire stacked electrode body.

[0072] In addition, it is preferred that the thickness of the first uncoated portion (in Figure 3 The thickness of the uncoated portion 52B of the negative electrode current collector 520) is greater than the thickness of the second uncoated portion (in Figure 3 The thickness of the uncoated portion 42B of the positive electrode current collector 420 is greater than that of the positive electrode current collector 420. It should be noted that the thickness refers to the average thickness, which is the arithmetic mean of the thicknesses of 10 points randomly selected from the corresponding parts.

[0073] By increasing the thickness of the first uncoated portion, it is possible to preferentially dissipate heat from the central portion where heat is particularly likely to be concentrated.

[0074] exist Figure 1 In the battery cell 20 shown in FIG. 1 , the first uncoated portion 52B of the negative electrode current collector 520 is exposed to the outside through the welded portion formed by welding the ends of the two films together. Figure 3 In the battery cell 20 shown, the first uncoated portion 52B of the negative electrode current collector 520 and the second uncoated portion 42B of the positive electrode current collector 420 are exposed to the outside through the welded portion formed by welding the ends of the two films to each other. However, in the welded portion, the current collector exists between the two films at the location where these uncoated portions exist, and is tightly attached to the two films. From the viewpoint of improving the weldability and airtightness, it is preferred to perform at least one of a roughening treatment and a carbon coating treatment on the surface of the first uncoated portion 52B and the second uncoated portion 42B that pass through the welded portion of the battery cell case 7.

[0075] It should be noted that in Figure 1 and Figure 3 In the embodiment of the present disclosure, the stacked electrode bodies are shown, but the battery cell of the embodiment of the present disclosure is not limited to this. For example, a wound electrode body unit having a wound electrode body inside may be used.

[0076] Next, a battery module, a battery pack, and a vehicle including a battery cell according to an embodiment of the present disclosure will be described using the drawings.

[0077] (Overall Structure of Vehicle 100)

[0078] Figure 4 1 is a schematic top view showing the main parts of a vehicle 100 to which the battery pack 10 according to the embodiment is applied. Figure 4 As shown, the vehicle 100 is an electric vehicle (BEV: Battery Electric Vehicle) equipped with a battery pack 10 under the floor. It should be noted that the arrows UP, FR, and LH in the respective figures indicate the upper side in the vehicle vertical direction, the front side in the vehicle front-rear direction, and the left side in the vehicle width direction, respectively. When the front-rear, left-right, up-down directions are used for explanation, unless otherwise specified, they indicate the front-rear direction in the vehicle front-rear direction, the left-right direction in the vehicle width direction, and the up-down direction in the vehicle vertical direction.

[0079] As an example, the vehicle 100 of the present embodiment has a DC / DC converter 102, an electric compressor 104, and a PTC (Positive Temperature Coefficient) heater 106 disposed on the front side of the vehicle relative to the battery pack 10. In addition, a motor 108, a gear box 110, an inverter 112, and a charger 114 are disposed on the rear side of the vehicle relative to the battery pack 10.

[0080] The DC current output from battery pack 10 is supplied to electric compressor 104, PTC heater 106, inverter 112, etc. after the voltage is adjusted by DC / DC converter 102. In addition, by supplying power to motor 108 via inverter 112, the rear wheels rotate and vehicle 100 travels.

[0081] A charging port 116 is provided on the right side of the rear portion of the vehicle 100 . By connecting a charging plug of an external charging device (not shown) to the charging port 116 , electric power can be stored in the battery pack 10 via the on-vehicle charger 114 .

[0082] It should be noted that the configuration and structure of the various components constituting the vehicle 100 are not limited to the above-mentioned structure. For example, it can also be applied to a hybrid vehicle (HV: Hybrid Vehicle) or a plug-in hybrid vehicle (PHEV: Plug-in Hybrid Electric Vehicle) equipped with an engine. In addition, in the present embodiment, the motor 108 is mounted on the rear of the vehicle and is a rear-wheel drive vehicle, but it is not limited to this. It can be a front-wheel drive vehicle with the motor 108 mounted on the front of the vehicle, or a pair of motors 108 can be mounted on the front and rear of the vehicle. In addition, it can also be a vehicle with a hub motor on each wheel.

[0083] Here, the battery pack 10 is configured to include a plurality of battery modules 11. In the present embodiment, as an example, 10 battery modules 11 are provided. Specifically, five battery modules 11 are arranged along the vehicle front-rear direction on the right side of the vehicle 100, and five battery modules 11 are arranged along the vehicle front-rear direction on the left side of the vehicle 100. In addition, each battery module 11 is electrically connected.

[0084] Figure 5 1 is a schematic three-dimensional diagram of the battery module 11. Figure 5 As shown, the battery module 11 is formed into a substantially rectangular parallelepiped shape with the vehicle width direction as the length direction. In addition, the outer shell of the battery module 11 is formed of an aluminum alloy. For example, an aluminum die-cast product is joined to both ends of an extruded material of an aluminum alloy by laser welding or the like, thereby forming the outer shell of the battery module 11.

[0085] A pair of voltage terminals 12 and a connector 14 are provided at both ends of the battery module 11 in the vehicle width direction. A flexible printed circuit board 22 described later is connected to the connector 14. Bus bars (not shown) are welded to both ends of the battery module 11 in the vehicle width direction.

[0086] The battery module 11 has a length MW in the vehicle width direction of, for example, 350 mm to 600 mm, a length ML in the vehicle front-rear direction of, for example, 150 mm to 250 mm, and a height MH in the vehicle vertical direction of, for example, 80 mm to 110 mm.

[0087] Figure 6 FIG. 1 is a top view of the battery module 11 with the upper cover removed. Figure 6 As shown, a plurality of battery cells 20 are accommodated in an aligned state inside the battery module 11. In the present embodiment, as an example, 24 battery cells 20 are aligned in the vehicle front-rear direction and bonded to each other.

[0088] A flexible printed circuit (FPC) 22 is disposed on the battery cell 20. The flexible printed circuit 22 is formed in a strip shape with the vehicle width direction as the longitudinal direction, and thermistors 24 are provided at both ends of the flexible printed circuit 22. The thermistor 24 is a structure that is not bonded to the battery cell 20 and is pressed toward the battery cell 20 by the upper cover of the battery module 11.

[0089] In addition, one or more buffers (not shown) are stored inside the battery module 11. For example, the buffer is a thin plate-shaped member that can be elastically deformed and is arranged between the battery cells 20 adjacent to each other in the thickness direction of the arrangement direction of the battery cells 20. In this embodiment, as an example, buffers are arranged at both ends in the longitudinal direction and the central part in the longitudinal direction of the battery module 11.

[0090] Figure 7 2 is a schematic diagram of a battery cell 20 housed in a battery module 11 as viewed from the thickness direction. Figure 7 As shown, the battery cell 20 is formed in a substantially rectangular plate shape, and an electrode body (not shown) is accommodated inside. The electrode body is formed by laminating a positive electrode, a negative electrode, and a separator, and is sealed by a laminate film 28 .

[0091] In this embodiment, as an example, the storage part of the electrode body is formed by folding and laminating the sheet-shaped laminate film 28 after embossing. It should be noted that both single-cup embossing structure with embossing at one location and double-cup embossing structure with embossing at two locations can be adopted, but in this embodiment, a single-cup embossing structure with a drawing depth of about 8 mm to 10 mm is used.

[0092] The upper ends of both ends of the battery cell 20 in the longitudinal direction are bent, and the corners form contours. In addition, the upper end of the battery cell 20 is bent, and a fixing band 30 is wound around the upper end of the battery cell 20 along the longitudinal direction.

[0093] Here, terminals (tabs) 26 are provided at both ends of the battery cell 20 in the longitudinal direction. In the present embodiment, as an example, the terminals 26 are provided at positions offset downward from the vertical center of the battery cell 20. The terminals 26 are joined to bus bars (not shown) by laser welding or the like.

[0094] The length CW1 of the battery cell 20 in the vehicle width direction is, for example, 530 mm to 600 mm, the length CW2 of the region storing the electrode body is, for example, 500 mm to 520 mm, and the height CH of the battery cell 20 is, for example, 80 mm to 110 mm. In addition, the thickness of the battery cell 20 is, for example, 7.0 mm to 9.0 mm, and the height TH of the terminal 26 is, for example, 40 mm to 50 mm.

[0095] Module housing in battery modules

[0096] It should be noted that the battery module may be further housed in a battery module housing. In this case, preferably, the first exposed portion (preferably the first exposed portion and the second exposed portion, and more preferably all exposed portions) in the battery cell is insulated and joined to the battery module housing. By insulating and joining the exposed portion to the battery module housing, the heat generated from the electrode body can be dissipated more efficiently.

[0097] Coolers in battery modules

[0098] The battery module may also include a cooler. In this case, it is preferred that the first exposed portion (preferably the first exposed portion and the second exposed portion, and more preferably all exposed portions) in the battery cell be insulated and joined to the cooler. By insulating and joining the exposed portion to the cooler, the heat generated from the electrode body can be dissipated more efficiently.

[0099] In addition, as a method of insulating bonding, potting and bonding using alumina are mentioned, for example.

Claims

1. A battery cell, comprising: an electrode body further including a plurality of stacked structures, the stacked structures having a positive electrode, a negative electrode, and a separator interposed between the positive electrode and the negative electrode; and The battery cell casing has the electrode body enclosed therein, wherein: The positive electrode and the negative electrode each include a current collector and a composite material containing an active material and coated on a surface of the current collector. At least one of the current collector of the positive electrode and the current collector of the negative electrode has an uncoated portion on the peripheral edge of the surface where the composite material is not coated, Among the current collectors having the uncoated portions, the uncoated portion of the current collector that is the longest in distance from the surface of the cell case is defined as a first uncoated portion that extends to the outside of the cell case and includes a first exposed portion.

2. The battery cell according to claim 1, wherein: The electrode surface of the electrode body has a rectangular shape, and the first exposed portion is arranged on a long side of the rectangular shape.

3. The battery cell according to claim 1 or 2, wherein: The electrode surface of the electrode body has a rectangular shape, and the electrode having a longer side of the rectangular shape of the positive electrode and the negative electrode has the first exposed portion.

4. The battery cell according to claim 1 or 2, wherein: The uncoated portion of the current collector having a smaller distance from the surface of the cell case than the current collector having the first uncoated portion is defined as a second uncoated portion extending to the outside of the cell case and having a second exposed portion.

5. The battery cell according to claim 4, wherein: A portion where the first uncoated portion and the second uncoated portion are joined is provided inside the battery cell case.

6. The battery cell according to claim 4, wherein: The first uncoated portion has a plate thickness greater than that of the second uncoated portion.

7. A battery module comprising: The battery cell according to any one of claims 1 to 6; and at least one of a cooler and a battery module housing, wherein The first exposed portion is insulated and joined to at least one of the cooler and the battery module case.

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