JP5831213B2 - Secondary battery, vehicle - Google Patents

Description

  The present invention relates to a secondary battery and a vehicle equipped with the secondary battery.

  Conventionally, lithium ion secondary batteries and nickel metal hydride secondary batteries are known as secondary batteries. Such a secondary battery has, for example, a configuration in which an electrode body (electrode group) is formed by winding an electrode sheet (electrode) with an insulating separator interposed, and the electrode body is housed in a case. ing. And in a secondary battery, while providing the current collection member joined with the electrode sheet | seat of an electrode body, this current collection member is electrically connected with respect to the electrode terminal provided so that it may protrude from a case (for example, Patent Document 1).

JP 2003-249423 A

  By the way, in the secondary battery, the performance may be deteriorated due to the heat generation of the electrode body accompanying the environmental temperature or charging / discharging. For this reason, in a conventional secondary battery, temperature adjustment is performed by flowing a heat exchange medium (heat medium) outside the case, and such performance degradation is suppressed. In the secondary battery of Patent Document 1, since the current collecting member is connected to the electrode terminal, heat exchange can be performed between the electrode body and the case via the current collecting member. However, from the viewpoint of suppressing the performance deterioration of the secondary battery, it has been expected that the efficiency of heat exchange between the electrode body and the case is further increased and the temperature is adjusted quickly.

  The present invention has been made paying attention to the problems existing in the prior art, and an object of the present invention is to provide a secondary battery and a vehicle capable of suitably adjusting the temperature.

In order to solve the above-mentioned problem, the invention according to claim 1 is a secondary battery comprising a case in which an electrode group in which a positive electrode sheet and a negative electrode sheet that are insulated with a separator sandwiched therebetween has a layered structure is housed in a case. a battery, comprising: a flat plate portion, a connecting portion for connecting the electrode group and said plate comprises a current collecting member made of a conductive material, one face of said plate inner surface of the front Symbol case Between the case and an insulating layer made of an insulating material formed on the inner surface of the case, and is connected to the case on the other surface. Are electrically and thermally connected , the case is made of metal, and the case has a bottomed cylindrical shape having a bottom portion and a wall portion erected from the periphery of the bottom portion, and accommodates the electrode group. A main body member that is aligned with the inner surface of the case in the flat plate portion. And a taper that is inclined toward the electrode group toward the bottom of the main body member on the bottom surface side of the main body member on the surface that meets the inner surface of the wall portion. The gist is that the section is provided . Here, “thermally connected” indicates a state in which heat exchange can be performed, and it does not matter whether or not they are directly connected.

According to this, the case in the state one surface of which an insulating layer made of an insulating material formed on the inner surface of the state or case through the sheet made of an insulating material between the inner surface of the to case flat portion And a connecting portion is electrically and thermally connected to the other surface. For this reason, compared with the structure which connects a current collection member (flat plate part) with a case thermally with the other surface where the connection part was connected, a current collection member is thermally connected with a case in a wider area. Is possible. Thereby, the efficiency of heat exchange with an electrode group and a case can be improved, and temperature control can be performed rapidly. Therefore, temperature adjustment can be suitably performed. Further, the flat plate portion is arranged in a state of being fitted to the inner surface of the wall portion of the main body member, and further, a taper that is inclined toward the electrode group side toward the bottom portion of the main body member on the bottom side of the main body member in the surface mating with the inner surface of the wall portion. Is provided. For this reason, when the electrode group is housed in the main body member together with the current collecting member in a state where the connection portion and the electrode group are connected, the insertion property of the electrode group can be improved by being guided by the tapered portion. .

  According to a second aspect of the present invention, in the secondary battery according to the first aspect, a sheet made of an insulating material is interposed between a surface of the flat plate portion that meets the inner surface of the case and an inner surface of the case. It is a summary. According to this, it is possible to increase the efficiency of heat exchange between the electrode group and the case while ensuring the insulation between the current collecting member and the case.

The gist of the invention described in claim 3 is that the secondary battery according to claim 1 or 2 is mounted in a vehicle. According to this, since temperature adjustment can be suitably performed as a secondary battery, performance degradation due to environmental temperature and heat generation of the electrode body due to charge / discharge is suppressed, and for example, the replacement frequency of the secondary battery is increased. Moreover, it can suppress that the electric energy which can be utilized by one full charge falls.

  According to the present invention, temperature adjustment can be suitably performed.

The fragmentary sectional view which shows a lithium ion secondary battery typically. (A) is the left view which shows a lithium ion secondary battery typically, (b) is the AA line partial expanded sectional view shown to (a). The partial expanded sectional view which shows typically the lithium ion secondary battery in another embodiment. (A) is sectional drawing which shows typically the lithium ion secondary battery in another embodiment, (b) is a left view similarly.

Hereinafter, an embodiment embodying the present invention will be described with reference to FIGS. 1 and 2.
As shown in FIG. 1, a lithium ion secondary battery (hereinafter simply referred to as “secondary battery”) 10 includes a case 11 having a flat, generally cubic shape as a whole. The case 11 includes a main body member 12 formed in a flat bottomed substantially square cylinder shape, and a lid member having a substantially rectangular flat plate shape that is assembled to the main body member 12 so as to cover (seal) the opening of the main body member 12. 13. The main body member 12 and the lid member 13 are both made of metal (for example, stainless steel or aluminum). Hereinafter, for convenience of explanation, the longitudinal direction of the case 11 indicated by the arrow Y1 in FIG. 1 is indicated as the left-right direction, and the height direction of the case 11 indicated by the arrow Y2 is indicated as the up-down direction. In addition, the short direction of the case 11 indicated by the arrow Y3 in FIG.

  As shown in FIG. 1, the lid member 13 is provided with a positive electrode terminal 15 and a negative electrode terminal 16 that are formed in a substantially columnar shape from the upper surface of the lid member 13 so as to protrude upward. Further, the lower surface (inner surface) of the lid member 13 is made of a metal (aluminum in the present embodiment) as a conductive material (conductor), and is connected to the positive terminal 15 at the base end ( One end) is fixed. Further, the lower surface (inner surface) of the lid member 13 is made of a metal (copper in the present embodiment) as a conductive material (conductor), and is connected to the negative terminal 16 at the base end ( One end) is fixed. In the present embodiment, the current collecting terminals 17 and 18 are current collecting members.

  In addition, in the case 11, an electrode body 23 as an electrode group formed in a flat shape extending along the left-right direction (longitudinal direction of the case 11) as a whole is a sheet (insulating material) made of an insulating material (insulator). The film is stored in an insulating bag 11a formed of a film. 1 to 4, the insulating bag 11 a is shown to be slightly thinner than the main body member 12, but in fact, it is much thinner than the main body member 12 and ignores the thickness (substantially omitted). It is formed to the extent possible.

  The electrode body 23 has a separator (diaphragm) 27 interposed therebetween, a positive electrode sheet 28 as a positive electrode sheet having a long rectangular sheet shape, and a negative electrode sheet as a negative electrode sheet having a long rectangular sheet shape. It is formed by laminating 29 by winding in a spiral shape. That is, in the electrode body 23, the positive electrode sheet 28 and the negative electrode sheet 29 insulated with the separator 27 interposed therebetween have a layered structure. The positive electrode sheet 28 is formed by applying a positive electrode active material to a metal foil (in this embodiment, an aluminum foil), while the negative electrode sheet 29 is formed in a metal foil (in this embodiment, a copper foil) with a negative electrode. It is formed by applying an active material. The separator 27 is a long porous sheet made of an insulating resin material (for example, polyethylene). In the electrode body 23, separators 27 are disposed on the innermost periphery and the outermost periphery.

  In addition, the positive electrode sheet 28 is provided with a non-coated region 28a to which a positive electrode active material is not applied so as to extend in the longitudinal direction of the positive electrode sheet 28 with a constant width from the left end thereof, and a negative electrode sheet 29. The non-application area | region 29a in which the negative electrode active material is not apply | coated is set so that it may extend in the longitudinal direction of the negative electrode sheet 29 with a fixed width from the right end. And the electrode sheets 28 and 29 of this embodiment are wound in the state which piled up the application | coating area | region T with which the active material was apply | coated. Thereby, the positive electrode lead 24 in which the metal foil of the positive electrode sheet 28 is laminated is formed on the left end portion of the electrode body 23, while the negative electrode in which the metal foil of the negative electrode sheet 29 is laminated on the right end portion. Leads 25 are formed. In the positive electrode lead 24 and the negative electrode lead 25, the separator 27 is not interposed between the metal foils. The positive electrode lead 24 is electrically connected to the tip (one end) of the current collecting terminal 17, while the negative electrode lead 25 is electrically connected to the tip (one end) of the current collecting terminal 18. It is connected to the. The case 11 is filled with a liquid or gel electrolyte (not shown).

Hereinafter, the characteristic current collecting terminals 17 and 18 in the secondary battery 10 of this embodiment will be described in detail.
In the present embodiment, the current collecting terminal 17 and the current collecting terminal 18 are symmetrical in shape. The joining structure of the current collecting terminal 17 and the positive electrode sheet 28 (positive electrode lead 24) and the joining structure of the current collecting terminal 18 and the negative electrode sheet 29 (negative electrode lead 25) are symmetrical. . Therefore, in the following description, only the current collecting terminal 17 and the junction structure between the current collecting terminal 17 and the positive electrode sheet 28 will be described in detail, and the current collecting terminal 18, the current collecting terminal 18 and the negative electrode sheet 29 will be described in detail. The description of the joint structure is simplified by attaching the same reference numerals.

  The current collecting terminal 17 has a rectangular flat plate shape extending in the left-right direction, and is connected downward to the connecting portion 30 electrically connected to the positive electrode terminal 15 and the outer end (here, the left end portion) of the connecting portion 30 in the left-right direction. A hanging portion 31 as a flat plate portion having a substantially rectangular flat plate shape is provided. As shown in FIGS. 1 and 2, the drooping portion 31 has an outer surface 31 a disposed on the side opposite to the electrode body 23 provided (standing) on the body member 12 around the bottom portion 12 a. It arrange | positions so that the inner wall surface of the left wall part 12b may be opposed among wall parts. That is, the outer side surface 31 a of the hanging portion 31 is arranged in a state where it is in contact with the inner surface of the case 11, more specifically, in a state where it is aligned with the inner surface of the left wall portion 12 b in the main body member 12.

  The hanging portion 31 extends along the left wall portion 12b so that the entire surface (substantially the entire surface) of the outer side surface 31a is in contact (contacted) with the inner wall surface of the left wall portion 12b via the insulating bag 11a. Has been placed. That is, the insulating bag 11 a is sandwiched between the inner wall surface (inner surface) of the case 11 and the outer surface 31 a of the hanging portion 31. For this reason, in the current collecting terminal 17, the outer surface 31 a of the hanging portion 31 is in close contact with the insulating bag 11 a, and the insulating bag 11 a is in close contact with the inner wall surface (inner surface) of the case 11. The outer surface 31a is formed flat (smooth). As described above, the insulating bag 11 a is interposed between the outer surface 31 a of the hanging portion 31 and the inner surface of the case 11.

  Further, as shown in FIG. 2A, the hanging portion 31 has a size along the front-rear direction slightly smaller than a size along the front-rear direction on the inner wall surface of the left wall portion 12b, and in the up-down direction. The size along the upper wall of the left wall portion 12b is about two-thirds of the size along the vertical direction. The drooping portion 31 is formed such that the size along the front-rear direction is larger than the size along the front-rear direction of the electrode body 23 (positive electrode lead 24), and the size along the vertical direction is the electrode. The body 23 (positive electrode lead 24) is formed to have a size of about two thirds of the size along the vertical direction. Therefore, the drooping portion 31 is formed so as to cover more than half of the electrode body 23 (positive electrode lead 24) in the left side view. The drooping portion 31 of the present embodiment is interposed (inserted) between the electrode body 23 and the case 11 (main body member 12).

  As shown in FIGS. 1 and 2, a taper portion 32 that is inclined toward the electrode body 23 toward the bottom portion 12 a of the main body member 12 is formed on the outer surface 31 a of the hanging portion 31 on the bottom portion 12 a side of the main body member 12. Is provided. The tapered portion 32 is linear in a front view so that the lower end portion (tip portion) is located on the inner side in the left-right direction (here, on the right side) than the connecting portion (base portion) connected to the hanging portion 31. It is formed so as to be inclined. That is, the taper portion 32 is inclined toward the bottom portion 12a of the main body member 12 so as to be separated from the left wall portion 12b. The size of the tapered portion 32 along the front-rear direction is the same (substantially the same) as the size of the hanging portion 31 along the front-rear direction.

  As shown in FIG. 2, in the hanging portion 31, the inner side surface 31 b disposed on the electrode body 23 side has a substantially rectangular wall extending from the inner side surface 31 b toward the inner side in the left-right direction (here, the right side). A pair of joint portions 35 and 36 having a shape are provided. The joint portions 35 and 36 of the present embodiment are formed in the same shape (substantially the same shape), are opposed to each other, are paired, and are arranged so as to be parallel to each other.

  Each of the joint portions 35 and 36 is disposed so as to be inserted between the positive electrode leads 24 of the electrode body 23. The positive electrode lead 24 is bonded to the bonding portions 35 and 36 by ultrasonic bonding or welding, whereby the current collecting terminal 17 and the positive electrode lead 24 are electrically connected. As with the current collecting terminal 17, the current collecting terminal 18 of the present embodiment has an outer surface 31 a of the hanging portion 31 via an insulating bag 11 a (intervening) and an inner wall surface (inner surface) of the right wall portion 12 c. It is arranged to touch. Therefore, the length from the outer surface 31a of the drooping portion 31 of the current collecting terminal 17 to the outer surface 31a of the drooping portion 31 of the current collecting terminal 18 is the distance between the left wall portion 12b and the right wall portion 12c of the main body member 12. The length is set slightly smaller than the distance (substantially the same length). As described above, the joint portions 35 and 36 serve as connection portions that connect the hanging portions 31 and the electrode bodies 23 in the current collecting terminals 17 and 18.

Next, a method for manufacturing the secondary battery 10 will be described.
As shown in FIG. 1, after the electrode sheets 28 and 29 are wound and laminated with a separator 27 interposed therebetween, they are further pressed (compressed) in the front-rear direction to form a flat shape. 23 is obtained. At this time, the electrode sheets 28 and 29 are wound in a state where the application regions T of the active material are overlapped and the separators 27 are interposed so as to correspond to the application regions T. As a result, a positive electrode lead 24 is formed at the left end portion of the electrode body 23, and a negative electrode lead 25 is formed at the right end portion of the electrode body 23. Further, the current collecting terminals 17 and 18 are obtained (prepared) in a process different from the process of obtaining the electrode body 23.

  The positive electrode lead 24 of the electrode body 23 is joined to the joint portions 35 and 36 by ultrasonic joining or welding, and is electrically connected to the current collecting terminal 17. Similarly, the negative electrode lead 25 of the electrode body 23 is joined to the joint portions 35 and 36 by ultrasonic joining or welding and is electrically connected to the current collecting terminal 18.

  Thereafter, the positive terminal 15 is electrically connected to the current collecting terminal 17, while the negative terminal 16 is connected to the current collecting terminal 18. Next, the electrode body 23 to which the current collecting terminal 17 and the current collecting terminal 18 are joined is housed in the insulating bag 11a and is inserted into the main body member 12 from above. At this time, the electrode body 23 is guided so that the tapered portion 32 is positioned at the approximate center in the left-right direction by contacting the opening edge of the main body member 12 and the wall portions 12b and 12c via the insulating bag 11a. The Therefore, the insertability of the electrode body 23 into the main body member 12 can be improved. Further, it is possible to prevent the electrode body 23 from being damaged due to contact with the main body member 12 when the electrode body 23 is inserted.

  Then, the lid member 13 is assembled to the main body member 12 with the positive electrode terminal 15 and the negative electrode terminal 16 protruding from the upper surface, and finally, the electrolyte is filled to complete the secondary battery 10.

Next, the operation of the secondary battery 10 will be described.
First, a case where the temperature of the electrode body 23 becomes higher than the heat exchange medium (heat medium) flowing outside the secondary battery 10 (case 11) due to heat generated by charging / discharging through the positive terminal 15 and the negative terminal 16. explain.

  In this case, as shown in FIG. 2 (b), the heat generated in the electrode body 23 is transmitted to the electrode lead 24 mainly through the metal foil of the electrode sheets 28 and 29, and further from the positive electrode lead 24. It is transmitted to the joint portions 35 and 36 of the current collecting terminal 17 (indicated by the arrow Ya). The heat transmitted to the current collecting terminal 17 is transmitted from the outer surface 31a of the hanging part 31 to the case 11 (main body member 12) through the insulating bag 11a. The heat transferred to the case 11 is dissipated by heat exchange with the heat exchange medium (heat medium) flowing outside the case 11 (indicated by an arrow Yb). The heat generated in the electrode body 23 is similarly transmitted from the negative electrode lead 25 and the current collecting terminal 18 to the case 11 (main body member 12) and radiated. Thus, in the secondary battery 10 of this embodiment, the electrode body 23 accommodated inside can be rapidly cooled.

Next, the case where the temperature of the electrode body 23 becomes lower than the heat exchange medium (heat medium) flowing outside the secondary battery 10 (case 11) in a low temperature environment or the like will be described.
In this case, the heat transmitted from the heat exchange medium (heat medium) to the case 11 (main body member 12) is transmitted from the outer surface 31a of the hanging part 31 to the current collecting terminal 17 via the insulating bag 11a. The heat transmitted to the current collecting terminal 17 is transmitted from the joint portions 35 and 36 to the positive electrode lead 24 and is transmitted to the electrode body 23 mainly through the metal foil of the electrode sheets 28 and 29. The heat transmitted from the heat exchange medium to the case 11 (main body member 12) is also transmitted from the negative electrode lead 25 and the current collecting terminal 18 to the electrode body 23. Thus, in the secondary battery 10 of this embodiment, the electrode body 23 accommodated in the inside can be quickly heated (heated).

  As described above, in the secondary battery 10 according to the present embodiment, the current collecting terminals 17 and 18 are connected to the case 11 (main body) on the outer surface 31a opposite to the surface where the joint portions 35 and 36 are provided in the hanging portion 31. It is thermally connected (coupled) to the member 12). More specifically, in each current collecting terminal 17, 18, one surface (outer surface 31 a) of the hanging portion 31 is in contact with the inner surface (inner surface) of the case 11 with the insulating bag 11 a interposed between the case 11 and the heat. The joints 35 and 36 are electrically and thermally connected to the other surface (inner side surface 31b).

  For this reason, the contact area of the hanging part 31 and the case 11 can be widened compared with the structure thermally connected (coupled) with the case on the surface provided with the joint portions 35 and 36. That is, the current collecting terminals 17 and 18 and the case 11 can be thermally connected in a wider area. Thereby, the efficiency of heat exchange between the electrode body 23 and the case 11 can be further increased, and the temperature can be adjusted quickly.

Therefore, according to the above embodiment, the following effects can be obtained.
(1) One surface (outer surface 31a) of the hanging portion 31 is thermally connected to the case 11 with an insulating bag 11a made of an insulating material between the inner surface of the case 11 and the other surface (inner Joints 35, 36 are electrically and thermally connected to the side surface 31b). For this reason, compared with the structure which connects the current collection terminals 17 and 18 and the case 11 thermally with the surface (outer surface 31a) in which the junction parts 35 and 36 were provided, the current collection terminals 17 and 18 in a wider area. 18 and the case 11 can be thermally connected. Thereby, the efficiency of heat exchange with the electrode body 23 and the case 11 can be improved, and temperature control can be performed rapidly. Therefore, temperature adjustment can be suitably performed.

  (2) In each current collecting terminal 17, 18, an insulating bag 11 a is interposed between the outer surface 31 a of the hanging part 31 and the inner surface of the case 11. Therefore, the efficiency of heat exchange between the electrode body 23 and the case 11 can be enhanced while ensuring the insulation between the current collecting terminals 17 and 18 and the case 11.

  (3) The hanging portion 31 of the current collecting terminal 17 is disposed so as to face the left wall portion 12b of the main body member 12, and further on the outer surface 31a of the hanging portion 31 on the bottom portion 12a side of the main body member 12, the bottom portion 12a. A tapered portion 32 that is inclined toward the electrode body 23 is provided. The same applies to the current collecting terminal 18. Therefore, when the electrode body 23 is housed in the main body member 12 together with the current collecting terminals 17 and 18 in a state in which the joint portions 35 and 36 and the electrode body 23 are joined (connected), the electrode body 23 is moved by the taper portion 32. By being guided, the insertability of the electrode body 23 can be improved.

  (4) The hanging portion 31 is interposed (inserted) between the electrode body 23 and the case 11. Therefore, the tip of each electrode lead 24, 25 does not contact the insulating bag 11a, and the separation distance can be reduced until the current collecting terminals 17, 18 and the case 11 (insulating bag 11a) are in contact. . More specifically, as shown in FIG. 2B, the metal foil is brought into contact with the tips of the electrode leads 24 and 25 when being joined to the joint portions 35 and 36, whereby the edge 24a of the metal foil. Is formed. For example, in the configuration in which the hanging portion 31 is not interposed between the electrode body 23 (tips of the electrode leads 24 and 25) and the case 11 as in Patent Document 1 described above, the edge 24a does not contact the insulating bag 11a. In addition, it is necessary to separate the current collecting terminals 17 and 18 from the case 11 (insulating bag 11a). For this reason, in Patent Document 1, a dead space is generated inside the secondary battery 10, which hinders downsizing of the secondary battery. On the other hand, in the secondary battery 10 of this embodiment, such a problem is solved suitably, the dead space in the secondary battery 10 inside can be reduced, and the secondary battery 10 can be reduced in size.

  (5) In particular, in the present embodiment, the drooping portion 31 is interposed (inserted) between the joint portion (edge 24 a) between the joint portions 35 and 36 and the electrode leads 24 and 25 and the case 11. Therefore, the contact between the edge 24a and the insulating bag 11a can be suitably prevented.

  (6) Moreover, in the outer side surface 31a of each hanging part 31, the part corresponding to the junction parts 35 and 36 by the side view is thermally connected with the case 11 via the insulating bag 11a. Therefore, the efficiency of heat exchange between the joint portions 35 and 36 and the case 11 can be further increased.

The embodiment is not limited to the above, and may be embodied as follows, for example.
As shown in FIG. 3, the positive electrode lead 24 may be joined so as to be inserted between the joint portions 35 and 36. The current collector terminal 18 and the negative electrode lead 25 can be similarly changed.

  As shown in FIG. 4A and FIG. 4B, the tapered portion 32 of the current collecting terminal 17 is formed so that the lower end portion (tip portion) is inserted inside the tip end of the positive electrode lead 24. May be. The current collecting terminal 18 can be similarly changed. By comprising in this way, when inserting the electrode body 23 in the main body member 12, it can suppress that the lower end part of the taper part 32 is caught in the opening edge part of the main body member 12, and can improve insertability more. it can. In this example, the area where the hanging part 31 is not inserted between the electrode body 23 and the case 11 increases, but the current collecting terminals 17 and 18 are provided on the surface where the joints 35 and 36 are provided. The contact area between the current collecting terminals 17 and 18 and the case 11 can be widened as compared with the configuration in which the case 11 and the case 11 are thermally connected.

  An insulating layer made of an insulating material (insulating resin or the like) may be formed on the inner surface of the case 11 (the main body member 12 and the lid member 13). In this case, the insulating bag 11a may be omitted, and the outer surface 31a of the hanging part 31 may be brought into contact with the inner surface of the case 11 (main body member 12).

The current collecting terminals 17 and 18 may be provided with one or three or more joint portions.
The taper portion 32 may be omitted from the current collecting terminals 17 and 18. In this case, the current collecting terminals 17 and 18 may be formed such that the size along the vertical direction of the hanging portion 31 is larger than the size along the vertical direction of the electrode body 23. That is, the current collecting terminals 17 and 18 may be formed so that the electrode body 23 is covered (included) by the hanging part 31 in a side view. Furthermore, the drooping portion 31 may be formed to have a size corresponding to the inner wall surface of the left wall portion 12b or the right wall portion 12c so as to be in contact with the entire inner wall surface.

  The drooping portion 31 and the tapered portion 32 may be formed in a flat plate shape that is elliptical or pentagonal in a side view. Moreover, you may form the taper part 32 in the circular arc shape curved to the electrode body 23 side by front view.

-As long as it is formed from a conductor (metal), the material of the current collecting terminals 17 and 18 may be appropriately changed.
The electrode body 23 may be laminated by folding the electrode sheets 28 and 29 into a bellows shape with a separator 27 interposed therebetween, and the plurality of positive electrode sheets 28 and the plurality of negative electrode sheets 29 are laminated. May be.

  The case 11 may be formed in a flat oval shape as a whole. In this case, the main body member 12 is formed in a substantially oval cylindrical shape with a bottom, and the hanging parts 31 of the current collecting terminals 17 and 18 are formed so as to form an arc along the inner wall surface of the main body member 12 in plan view. Good. Further, the case 11 may not have a flat shape such as a cylindrical shape or a rectangular parallelepiped shape.

  The electrode body 23 may be stored in the case 11 so that the width direction of the electrode sheets 28 and 29 is along the vertical direction. In this case, the positive electrode lead 24 is formed at the upper left end portion of the electrode body 23, and the negative electrode lead 25 is formed at the upper right end portion of the electrode body 23.

The secondary battery 10 may be embodied as a nickel hydride secondary battery.
-The secondary battery 10 of the above embodiment is mounted on a vehicle (for example, an industrial vehicle or a passenger vehicle) and is charged by a generator mounted on the vehicle, while the compressor for an air conditioner is supplied with electric power supplied from the secondary battery 10 Alternatively, an electric motor for driving the wheels or an electrical component such as a car navigation system may be driven. According to this, since the temperature adjustment can be suitably performed as the secondary battery 10, the performance deterioration due to the heat generation of the electrode body 23 due to the environmental temperature and charging / discharging is suppressed, for example, the replacement frequency of the secondary battery 10. It is possible to prevent the amount of power that can be used from being reduced or the amount of power that can be used from being fully charged once.

Hereinafter, a technical idea that can be grasped from the above embodiment will be additionally described.
(B) The secondary battery according to claim 3, wherein the tapered portion is inserted between the positive electrode sheet or the negative electrode sheet on the bottom side of the main body member.

  (B) The secondary battery according to any one of claims 1 to 3, and the technical idea (a), wherein the flat plate portion is interposed between the electrode body and the case.

  DESCRIPTION OF SYMBOLS 10 ... Lithium ion secondary battery (secondary battery), 11 ... Case, 11a ... Insulation bag (sheet), 12 ... Main body member, 12a ... Bottom part, 12b ... Left wall part, 12c ... Right wall part, 17, 18 ... Current collecting terminal (current collecting member), 23 ... Electrode body (electrode group), 27 ... Separator, 28 ... Positive electrode sheet (positive electrode sheet), 29 ... Negative electrode sheet (negative electrode sheet), 31 ... Hanging part (flat plate part) , 31a ... outer surface, 31b ... inner surface, 32 ... tapered portion, 35,36 ... joint portion (connecting portion).

Claims (3)

A secondary battery comprising a case in which an electrode group in which a positive electrode sheet and a negative electrode sheet that are insulated with a separator sandwiched therebetween has a layered structure is housed in a case,
A flat plate portion, and a connecting portion that connects the flat plate portion and the electrode group, and includes a current collecting member made of a conductive material,
The case and the heat in the state on one surface of which an insulating layer made of an insulating material formed on the inner surface of the state or the case via a sheet made of an insulating material between the inner surface of the front SL case said plate Connected to the other surface, the connecting portion is electrically and thermally connected to the other surface ,
The case is made of metal,
The case includes a main body member that accommodates the electrode group in a bottomed cylindrical shape having a bottom portion and a wall portion erected from the periphery of the bottom portion,
A surface of the flat plate portion that is aligned with the inner surface of the case is disposed in a state of being aligned with the inner surface of the wall portion, and a bottom surface side of the main body member that faces the inner surface of the wall portion faces the bottom portion of the main body member. And a tapered portion inclined toward the electrode group side .   2. The secondary battery according to claim 1, wherein a sheet made of an insulating material is interposed between a surface of the flat plate portion that meets the inner surface of the case and an inner surface of the case. Vehicle, characterized in that mounting the secondary battery according to claim 1 or 2.