Battery cell

Abstract

To accurately detect the temperature of a battery element.SOLUTION: A battery cell 10 includes a battery element 100, an exterior material 400 including a wound part 410 that is wound around the battery element 100 and an extracted part 420 that is extracted from the wound part 410, and a temperature sensor 500 that is disposed inside the extracted part 420 at least partially.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a battery cell. [Background technology]

[0002] In recent years, various types of battery cells have been developed. A battery cell has a battery element having a positive electrode, a negative electrode, and a separator.

[0003] Patent Document 1 describes an example of a battery cell. This battery cell includes an exterior material that seals a battery element. The battery element is provided with a positive electrode lead and a negative electrode lead. A temperature sensor is disposed in the negative electrode lead.

[0004] Patent Document 2 describes an example of a battery cell. In this battery cell, an electrode body is sealed with a single folded laminate film. A thermistor is disposed on the periphery of the electrode body of the folded laminate film. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2007-335352 A [Patent Document 2] JP 2007-141782 A Summary of the Invention [Problem to be solved by the invention]

[0006] In the battery cells described in Patent Documents 1 and 2, a temperature sensor is disposed around the battery element at a distance from the battery element. When the temperature sensor is disposed at a distance from the battery element, it may become difficult to accurately detect the temperature of the battery element depending on the distance between the temperature sensor and the battery element.

[0007] One object of the present invention is to accurately detect the temperature of a battery element. Other objects of the present invention will become apparent from the description of this specification. [Means for solving the problem]

[0008] One aspect of the present invention is as follows. 1. A battery element; an exterior material having a wound portion wound around the battery element and a drawn-out portion drawn out from the wound portion; a temperature sensor disposed at least partially within said drawer portion; A battery cell comprising: 2. The battery cell of claim 1, wherein the temperature sensor is at least partially sealed by the drawer portion. 3. The battery cell according to claim 1 or 2, wherein the drawn-out portion defines a space into which gas generated from the battery element enters. 4. The battery cell according to any one of 1. to 3., wherein the battery element and the drawn-out portion at least partially overlap each other. Effect of the Invention

[0009] According to the above aspect of the present invention, the temperature of the battery element can be detected accurately. [Brief description of the drawings]

[0010] [Figure 1] FIG. 2 is a perspective view of a battery module according to the embodiment; [Diagram 2] FIG. 2 is a perspective view of a battery cell according to an embodiment. [Diagram 3] FIG. 2 is a right side view of the battery element according to the embodiment with the exterior material removed. [Figure 4] 3 is a cross-sectional view taken along line AA in FIG. 2. [Diagram 5] 5A to 5C are diagrams for explaining an example of a manufacturing method of a battery cell according to an embodiment. [Figure 6] 5A to 5C are diagrams for explaining an example of a manufacturing method of a battery cell according to an embodiment. [Figure 7] FIG. 11 is a perspective view of a battery cell according to Modification 1. [Figure 8] FIG. 11 is a perspective view of a battery cell according to Modification Example 2. [Figure 9] FIG. 11 is a perspective view of a battery cell according to Modification 3. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, embodiments and modifications of the present invention will be described with reference to the drawings. In all the drawings, similar components are given similar reference numerals and descriptions thereof will be omitted as appropriate.

[0012] Fig. 1 is a perspective view of a battery module 1 according to an embodiment. Fig. 2 is a perspective view of a battery cell 10 according to an embodiment. Fig. 3 is a right side view of a battery element 100 according to an embodiment with an exterior material 400 removed. Fig. 4 is a cross-sectional view taken along line AA in Fig. 2.

[0013] For the sake of explanation, each figure is labeled with an X direction, a Y direction, and a Z direction. The X direction indicates the front-rear direction of the battery cell 10. The Y direction is perpendicular to the X direction. The Y direction indicates the left-right direction of the battery cell 10. The Z direction is perpendicular to both the X direction and the Y direction. The Z direction indicates the up-down direction of the battery cell 10. The direction indicated by the arrow indicating the X direction and the direction indicated by the arrow indicating the Z direction are the forward direction and the upward direction, respectively. For the sake of explanation, the direction indicated by the arrow indicating the Y direction as viewed from the front is the right direction, and the opposite direction to the direction indicated by the arrow indicating the Y direction as viewed from the front is the left direction. However, the relationship between the X direction, the Y direction, the Z direction, the front-rear direction, the left-right direction, and the up-down direction of the battery cell 10 is not limited to this example. In FIG. 3 and FIG. 4, a white circle with a black dot indicating the X direction or the Y direction indicates that the direction from the back of the paper to the front is the direction indicated by the arrow indicating that direction.

[0014] Hereinafter, where necessary, the direction perpendicular to the X direction will be referred to as the YZ plane direction, the direction perpendicular to the Y direction will be referred to as the ZX plane direction, and the direction perpendicular to the Z direction will be referred to as the XY plane direction.

[0015] The battery module 1 will be described with reference to FIG.

[0016] The battery module 1 according to the embodiment includes a plurality of battery cells 10, a plurality of elastic members 20, and a heat conducting element 30.

[0017] The multiple battery cells 10 are stacked in the Y direction. The battery cells 10 adjacent to each other in the Y direction are connected in series or in parallel via a front terminal 310 or a rear terminal 320, which will be described later. Three battery cells 10 are illustrated in FIG. 1 . However, the number of battery cells 10 included in the battery module 1 is not limited to three, and may be two, or may be four or more. Alternatively, the number of battery cells 10 included in the battery module 1 may be only one.

[0018] The elastic members 20 and the battery cells 10 are alternately arranged in the Y direction. In the example shown in FIG. 1, each elastic member 20 has a substantially sheet shape extending in a direction substantially parallel to the ZX plane. In the embodiment, each elastic member 20 is, for example, a compression pad. The battery cells 10 and the elastic members 20 are compressed in the Y direction by plates (not shown) located on both sides of the battery cells 10 and the elastic members 20 in the Y direction. Thus, each battery cell 10 is pressed in the Y direction by the bias of the adjacent elastic members 20. Therefore, it is easier to fix the position of each battery cell 10 in the Y direction compared to a case where the elastic members 20 are not provided.

[0019] An upper surface of the heat conducting element 30 and a lower surface of each battery cell 10 are thermally coupled to each other. The heat conducting element 30 is, for example, a thermal glue or a heat dissipation sheet. In one example, the multiple battery cells 10 are mounted on a lower plate of a housing (not shown) that houses the multiple battery cells 10 via the heat conducting element 30. Thus, heat can be conducted between each battery cell 10 and the lower plate via the heat conducting element 30.

[0020] The battery cell 10 will be described with reference to FIGS. 2 to 4, and with reference to FIG. 1 as necessary.

[0021] The battery cell 10 according to the embodiment includes a battery element 100, a front cover material 210, a rear cover material 220, a front terminal 310, a rear terminal 320, an exterior material 400, and a temperature sensor 500. The exterior material 400 has a wound portion 410 and a pulled-out portion 420.

[0022] The battery element 100 has a substantially rectangular parallelepiped shape. The dimension of the battery element 100 in the X direction is the dimension in the longitudinal direction of the battery element 100. The dimension of the battery element 100 in the Z direction is the dimension in the lateral direction of the battery element 100. The dimension of the battery element 100 in the Y direction is the dimension in the thickness direction of the battery element 100.

[0023] The battery element 100 has at least one positive electrode (not shown), at least one negative electrode (not shown), and at least a separator (not shown). In one example, a plurality of positive electrodes and a plurality of negative electrodes are alternately stacked in the Y direction. At least a portion of the separator is located between the positive electrodes and the negative electrodes adjacent in the Y direction. Specifically, in one example, each of a plurality of sheet-like separators is located between the positive electrodes and the negative electrodes adjacent in the Y direction. However, one sheet-like separator may be alternately folded back at the upper end of the positive electrode and the lower end of the negative electrode, or alternately folded back at the lower end of the positive electrode and the upper end of the negative electrode. Alternatively, the positive electrode, the negative electrode, and the separator may be wound so that the separator is disposed between the positive electrode and the negative electrode. In one example, the positive electrode, the negative electrode, and the separator are wound in a state in which both sides of one of the positive electrode and the negative electrode are covered by the separator. In another example, a laminate including a plurality of unit laminates including a positive electrode, a separator, and a negative electrode in this order may be wound, but the winding structure of the positive electrode, the negative electrode, and the separator is not limited to these examples.

[0024] In the embodiment, the battery cell 10 is a battery cell containing an electrolyte. However, the battery cell 10 may be an all-solid-state battery. In the all-solid-state battery, a solid electrolyte layer is provided in a portion corresponding to a separator. The all-solid-state battery does not contain an electrolyte. Hereinafter, unless otherwise specified, the battery cell 10 will be described as a battery cell containing an electrolyte.

[0025] The front cover member 210 covers the front end surface of the battery element 100. The front cover member 210 is made of, for example, at least one of resin and metal. When viewed from the X direction, the front cover member 210 has a substantially rectangular shape having a pair of short sides substantially parallel to the Y direction and a pair of long sides substantially parallel to the Z direction.

[0026] The rear cover member 220 covers the rear end surface of the battery element 100. The rear cover member 220 is made of, for example, at least one of resin and metal. When viewed from the X direction, the rear cover member 220 has a substantially rectangular shape having a pair of short sides substantially parallel to the Y direction and a pair of long sides substantially parallel to the Z direction.

[0027] The front terminal 310 is disposed on the front end surface side of the battery element 100. The front terminal 310 protrudes forward from the front cover member 210. The front terminal 310 is electrically connected to one of the positive electrode and the negative electrode included in the battery element 100 via the front current collector 110 drawn out from the front end surface of the battery element 100. When the front terminal 310 and the positive electrode are electrically connected to each other, the front terminal 310 functions as a positive electrode terminal. When the front terminal 310 and the negative electrode are electrically connected to each other, the front terminal 310 functions as a negative electrode terminal.

[0028] The rear terminal 320 is disposed on the rear end surface side of the battery element 100. The rear terminal 320 protrudes rearward from the rear cover member 220. The rear terminal 320 is electrically connected to the other of the positive electrode and the negative electrode included in the battery element 100 via the rear current collector 120 drawn out from the rear end surface of the battery element 100. Thus, the polarity of the front terminal 310 and the polarity of the rear terminal 320 are different from each other. When the rear terminal 320 and the positive electrode are electrically connected to each other, the rear terminal 320 functions as a positive electrode terminal. When the rear terminal 320 and the negative electrode are electrically connected to each other, the rear terminal 320 functions as a negative electrode terminal.

[0029] The exterior material 400 is, for example, a laminate film including a metal layer and resin layers provided on both sides of the metal layer.

[0030] The wound portion 410 is wound around the battery element 100, the front cover material 210, and the rear cover material 220 in the X direction. The wound portion 410 defines an internal space that accommodates the battery element 100 and an electrolyte (not shown). The inner peripheral surface of the front end of the wound portion 410 and the outer peripheral surface of the front cover material 210 are joined to each other by, for example, heat fusion. Thus, a sealing portion is formed between the inner peripheral surface of the front end of the wound portion 410 and the outer peripheral surface of the front cover material 210. The inner peripheral surface of the rear end of the wound portion 410 and the outer peripheral surface of the rear cover material 220 are joined to each other by, for example, heat fusion. Thus, a sealing portion is formed between the inner peripheral surface of the rear end of the wound portion 410 and the outer peripheral surface of the rear cover material 220.

[0031] The pulled-out portion 420, as an excess portion of the exterior material 400 relative to the wound portion 410, is pulled out from a portion of the wound portion 410 covering the upper right corner of the battery element 100. The pulled-out portion 420 is folded relative to the wound portion 410 so that the pulled-out portion 420 and the battery element 100 at least partially overlap each other in the Y direction. The pulled-out portion 420 may be pulled out from a portion of the wound portion 410 covering another corner of the battery element 100. Alternatively, the pulled-out portion 420 may be pulled out from a portion of the wound portion 410 covering the side surface of the battery element 100.

[0032] 4, the drawn-out portion 420 includes a first drawn-out portion 422, a second drawn-out portion 424, and a sealing portion 426. The first drawn-out portion 422 is drawn out from one end of the wound portion 410 around the X direction, and the second drawn-out portion 424 is drawn out from the other end of the wound portion 410 around the X direction. The first drawn-out portion 422 and the second drawn-out portion 424 are joined to each other via the sealing portion 426. The sealing portion 426 is formed by joining opposing surfaces of the first drawn-out portion 422 and the second drawn-out portion 424 to each other by, for example, heat fusion.

[0033] The temperature sensor 500 is a thermistor. The temperature sensor 500 is provided to detect the temperature of the battery element 100. As shown in Figs. 2 and 4, the temperature sensor 500 has a sealant 502 and a dumet wire 504. The sealant 502 is, for example, glass that seals a chip such as a thermistor chip. The dumet wire 504 is electrically connected to the chip sealed in the sealant 502. However, the structure of the temperature sensor 500 is not limited to the examples shown in Figs. 2 and 4.

[0034] 4, the seal 502 is disposed inside the drawn-out portion 420. Specifically, the seal 502 is disposed in the gap between the first drawn-out portion 422 and the second drawn-out portion 424. The Dumet wire 504 is drawn downward from the lower end of the seal 502 via the lower end of the drawn-out portion 420.

[0035] 4, the drawn-out portion 420 and the battery element 100 at least partially overlap each other in the Y direction. Thus, the sealing body 502 and the battery element 100 can be at least partially overlapped each other in the Y direction. Therefore, compared to a case in which the sealing body 502 is disposed around the battery element 100 at a distance from the battery element 100, the sealing body 502 and the battery element 100 can be brought closer to each other, and the temperature of the battery element 100 can be accurately detected.

[0036] 2 and 4, the sealing body 502 and the approximate central portion of the battery element 100 in the X and Z directions overlap each other in the Y direction. Therefore, compared to a case in which the sealing body 502 overlaps in the Y direction with a portion of the battery element 100 that is shifted in the X or Z direction from the approximate central portion of the battery element 100 in the X and Z directions, the temperature of the approximate central portion of the battery element 100 in the X and Z directions can be detected more accurately. However, the sealing body 502 may overlap in the Y direction with a portion of the battery element 100 that is shifted in at least one of the X and Z directions from the approximate central portion of the battery element 100 in the X and Z directions.

[0037] 2, the sealing portion 426 is formed over the entire drawn-out portion 420, except for the sealing body 502 and the vicinity of the sealing body 502 in the Y direction. Thus, a portion of the Dumet wire 504 is sealed by the drawn-out portion 420 below the sealing body 502. Thus, compared to a case where no portion of the temperature sensor 500 is sealed by the drawn-out portion 420, it is possible to suppress detachment of the temperature sensor 500 from the drawn-out portion 420. However, no portion of the temperature sensor 500 may be sealed by the drawn-out portion 420. When no portion of the temperature sensor 500 is sealed by the drawn-out portion 420, the temperature sensor 500 may simply be inserted into the gap between the first drawn-out portion 422 and the second drawn-out portion 424.

[0038] In one example, the encapsulant 502 may be in a substantially sheet shape extending in a direction substantially parallel to the ZX plane. When the encapsulant 502 is in a substantially sheet shape extending in a direction substantially parallel to the ZX plane, the influence of the thickness of the encapsulant 502 in the Y direction between the battery cells 10 adjacent in the Y direction can be suppressed in a state where a plurality of battery cells 10 are arranged in the Y direction as shown in FIG. 1, compared to a case where the thickness of the encapsulant 502 in the Y direction is relatively thick. Even if the thickness of the encapsulant 502 in the Y direction is relatively thick, the influence of the thickness of the encapsulant 502 in the Y direction can be suppressed by the elastic material 20 arranged between the battery cells 10 adjacent in the Y direction.

[0039] Figures 5 and 6 are diagrams for explaining an example of a manufacturing method for the battery cell 10 according to the embodiment. An example of a manufacturing method for the battery cell 10 according to the embodiment will be explained with reference to Figures 5 and 6 as necessary. In this example, the battery cell 10 is manufactured as follows.

[0040] First, the battery element 100 is formed. A front current collector 110 and a rear current collector 120 are drawn out from the front end surface and the rear end surface of the battery element 100, respectively.

[0041] Next, with the front terminal 310 already provided on the front cover member 210, the front current collector 110 and the front terminal 310 are electrically connected to each other. Similarly, with the rear terminal 320 already provided on the rear cover member 220, the rear current collector 120 and the rear terminal 320 are electrically connected to each other.

[0042] Next, the laminate film that constitutes the exterior material 400 is wrapped around the battery element 100, the front cover material 210 and the rear cover material 220 in the X direction to form the wrapped portion 410, and the pulled-out portion 420 is pulled out from the wrapped portion 410 as an excess portion of the exterior material 400 relative to the wrapped portion 410.

[0043] Next, the outer peripheral surface around the X direction of the front cover material 210 and the inner peripheral surface around the X direction of the front end of the wound portion 410 are joined together by heat fusion to form a sealed portion between the outer peripheral surface around the X direction of the front cover material 210 and the inner peripheral surface around the X direction of the front end of the wound portion 410. Similarly, the outer peripheral surface around the X direction of the rear cover material 220 and the inner peripheral surface around the X direction of the rear end of the wound portion 410 are joined together by heat fusion to form a sealed portion between the outer peripheral surface around the X direction of the rear cover material 220 and the inner peripheral surface around the X direction of the rear end of the wound portion 410.

[0044] As shown in FIG. 5, before the first and second drawn portions 422, 424 are joined together, there is an opening 428 between the tip of the first drawn portion 422 and the tip of the second drawn portion 424, which opens into the gap between the first and second drawn portions 422, 424.

[0045] 6, the first lead-out portion 422 and the second lead-out portion 424 are joined together by heat fusion to form a sealing portion 426, except for the region where the temperature sensor 500 is inserted. Next, the seal 502 and at least a portion of the Dumet wire 504 are inserted into a gap between the first lead-out portion 422 and the opening 428 through an opening 428 in a portion of the lead-out portion 420 where the sealing portion 426 is not formed. Next, the first lead-out portion 422 and the second lead-out portion 424 are joined together by heat fusion below the seal 502 to form a sealing portion 426 below the seal 502 as well, and a portion of the Dumet wire 504 is sealed by the lead-out portion 420 below the seal 502.

[0046] The method of sealing the Dumet wire 504 by the lead-out portion 420 is not limited to the above example. For example, at least a part of the temperature sensor 500 may be inserted into the gap between the first lead-out portion 422 and the second lead-out portion 424 through the opening 428 in a state where neither of the first lead-out portion 422 nor the second lead-out portion 424 is joined to each other. After at least a part of the temperature sensor 500 is inserted into the gap between the first lead-out portion 422 and the second lead-out portion 424, the first lead-out portion 422 and the second lead-out portion 424 may be joined to each other around the sealing body 502 in the Y direction to form a sealing portion 426. By forming the sealing portion 426 around the sealing body 502 in the Y direction, a part of the Dumet wire 504 is sealed by the lead-out portion 420 below the sealing body 502.

[0047] Next, an electrolyte is injected into the internal space of the wound portion 410 through an injection hole provided in at least one of the front cover member 210 and the rear cover member 220. Next, the injection hole is closed.

[0048] In this manner, the battery cell 10 is manufactured.

[0049] Fig. 7 is a perspective view of a battery cell 10A according to Modification 1. The battery cell 10A according to Modification 1 is similar to the battery cell 10 according to the embodiment, except for the following points: The battery cell 10A according to Modification 1 includes a battery element 100 not shown in Fig. 7, like the battery cell 10 according to the embodiment.

[0050] The exterior material 400A of the battery cell 10A according to the first modification has a wound portion 410A and a drawn-out portion 420A. The sealed portion 426A of the drawn-out portion 420A according to the first modification extends continuously along the front edge, rear edge, and bottom edge of the drawn-out portion 420A. Thus, the drawn-out portion 420A defines an internal space surrounded by the sealed portion 426A. The internal space of the drawn-out portion 420A and the internal space of the wound portion 410A are in communication with each other.

[0051] Gas may be generated from the battery element 100. In the first modification, the gas generated from the battery element 100 enters the internal space of the drawn-out portion 420A from the internal space of the wound portion 410A. The gas that has entered the internal space of the drawn-out portion 420A causes the drawn-out portion 420A to expand. Therefore, as in the example shown in FIG. 1, even if gas is generated from the battery element 100 of at least one battery cell 10A when multiple battery cells 10A are lined up in the Y direction, the expansion of the drawn-out portion 420A can ensure a distance between adjacent battery cells 10A in the Y direction.

[0052] In the first modification, the sealing body 502 is disposed in the internal space of the drawn-out portion 420A. Thus, similarly to the embodiment, the sealing body 502 and the battery element 100 can be overlapped with each other in the Y direction. Therefore, compared to a case in which the sealing body 502 is disposed around the battery element 100 at a distance from the battery element 100, the sealing body 502 and the battery element 100 can be brought closer to each other, and the temperature of the battery element 100 can be detected accurately.

[0053] In the first modification, the Dumet wire 504 is sealed by the drawn-out portion 420 at a portion extending along the lower edge of the drawn-out portion 420A of the sealing portion 426A. Therefore, compared to a case in which no portion of the temperature sensor 500 is sealed by the drawn-out portion 420, detachment of the temperature sensor 500 from the drawn-out portion 420 can be suppressed.

[0054] Fig. 8 is a perspective view of a battery cell 10B according to Modification 2. The battery cell 10B according to Modification 2 is similar to the battery cell 10 according to the embodiment, except for the following points. Like the battery cell 10 according to the embodiment, the battery cell 10B according to Modification 2 includes a battery element 100 that is not shown in Fig. 8.

[0055] The battery cell 10B according to Modification 2 includes a front cover member 210B, a front terminal 310B, an exterior material 400B, and a temperature sensor 500B. The front cover member 210B, front terminal 310B, exterior material 400B, and temperature sensor 500B according to Modification 2 correspond to the front cover member 210, front terminal 310, exterior material 400, and temperature sensor 500, respectively, according to the embodiment. The exterior material 400B according to Modification 2 includes a wound portion 410B and an drawn-out portion 420B. The temperature sensor 500B according to Modification 2 includes a seal 502B and a Dumet wire 504B.

[0056] The pulled-out portion 420B according to the second modification is an excess portion of the exterior material 400B relative to the wound portion 410B, and is pulled out from a portion of the wound portion 410B that covers the upper left corner of the battery element 100. The pulled-out portion 420B is folded relative to the wound portion 410B so that the pulled-out portion 420B and the battery element 100 at least partially overlap each other in the Z direction.

[0057] The sealing body 502B according to the second modification is disposed inside the drawn-out portion 420B. Therefore, the sealing body 502B and the battery element 100 can be overlapped with each other in the Z direction. Therefore, compared to a case where the sealing body 502B is disposed around the battery element 100 at a distance from the battery element 100, the sealing body 502B and the battery element 100 can be brought closer to each other, and the temperature of the battery element 100 can be detected accurately.

[0058] The Dumet wire 504B according to the second modification is drawn out to the right from the right end of the sealing body 502B via the right end of the drawn-out portion 420B. A sealing portion 426B is formed over the entire drawn-out portion 420B, except for the sealing body 502B and the vicinity of the sealing body 502B in the Z direction. Thus, a portion of the Dumet wire 504B is sealed by the drawn-out portion 420B on the right side of the sealing body 502B. Therefore, detachment of the temperature sensor 500B from the drawn-out portion 420B can be suppressed, compared to a case in which no portion of the temperature sensor 500B is sealed by the drawn-out portion 420B.

[0059] Fig. 9 is a perspective view of a battery cell 10C according to Modification 3. The battery cell 10C according to Modification 3 is similar to the battery cell 10 according to the embodiment, except for the following points: The battery cell 10C according to Modification 3 includes a battery element 100 not shown in Fig. 9, like the battery cell 10 according to the embodiment.

[0060] In the example shown in FIG. 9, the dumet wire 504 is drawn forward from the front end of the sealing body 502 via the front end of the drawn-out portion 420. As described with reference to FIG. 1, a battery module may be formed by stacking a plurality of battery cells 10C in the Y direction. In such a battery module, the dumet wire 504 and the wiring electrically connected to the dumet wire 504 can be easily arranged if the dumet wire 504 is drawn forward of the drawn-out portion 420 rather than being drawn downward of the drawn-out portion 420. The dumet wire 504 may be drawn rearward of the drawn-out portion 420. When a plurality of battery cells 10C are stacked in the Y direction, whether the dumet wire 504 of each battery cell 10C is drawn forward of the drawn-out portion 420 or drawn rearward of the drawn-out portion 420 may be different depending on each battery cell 10C.

[0061] 9, sealing portion 426 is formed over the entire drawn-out portion 420, except for sealing body 502 and the vicinity thereof in the Y direction. However, sealing portion 426 may extend continuously along the front, rear and bottom edges of drawn-out portion 420, similar to sealing portion 426A shown in FIG. 7, and drawn-out portion 420 may define an interior space surrounded by sealing portion 426, similar to drawn-out portion 420A shown in FIG.

[0062] Although the embodiment and modified examples of the present invention have been described above with reference to the drawings, these are merely examples of the present invention, and various configurations other than those described above can also be adopted.

[0063] In the embodiment and each modified example, the positive electrode terminal and the negative electrode terminal are disposed on opposite sides of the battery element 100 in the X direction. However, both the positive electrode terminal and the negative electrode terminal may be disposed on only one of the front end face side and the rear end face side in the X direction of the battery element 100. When both the positive electrode terminal and the negative electrode terminal are disposed on only one of the front end face side and the rear end face side in the X direction of the battery element 100, the front end face and the rear end face of the battery element 100 are covered by, for example, two lid materials. Alternatively, only the end face of the battery element 100 from which the positive electrode terminal and the negative electrode terminal are drawn may be covered by the lid material. When only the end face of the battery element 100 from which the positive electrode terminal and the negative electrode terminal are drawn is covered by the lid material, the exterior material 400 may be sealed on the opposite side of the lid material of the battery element 100 and folded along the battery element 100. [Explanation of symbols]

[0064] 1 Battery module, 10, 10A, 10B, 10C Battery cell, 20 Elastic material, 30 Thermal conductive element, 100 Battery element, 110 Front current collector, 120 Rear current collector, 210, 210B Front cover material, 220 Rear cover material, 310, 310B Front terminal, 320 Rear terminal, 400, 400A, 400B Exterior material, 410, 410A, 410B Winding portion, 420, 420A, 420B Pull-out portion, 422 First pull-out portion, 424 Second pull-out portion 426, 426A, 426B Sealing portion, 428 Opening, 500, 500B Temperature sensor, 502, 502B Sealing body, 504, 504B Dumet wire

Claims

1. A battery element; an exterior material having a wound portion wound around the battery element and a drawn-out portion drawn out from the wound portion; a temperature sensor disposed at least partially within said drawer portion; A battery cell comprising:

2. The battery cell of claim 1 , wherein the temperature sensor is at least partially enclosed by the lead portion.

3. The battery cell according to claim 1 or 2, wherein the drawn-out portion defines a space into which gas generated from the battery element enters.

4. The battery cell according to claim 1 or 2, wherein the battery element and the lead-out portion at least partially overlap each other.

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