JP2013089318A - Secondary battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a malfunction from occurring by a temperature of an electrode body exceeding an acceptable range.SOLUTION: A positive electrode side current collector terminal 30A and positive electrode 12, or at least one of a negative electrode side current collector terminal and a negative electrode, are connected with a first to a sixth connection members 51 to 56, capable of shutting off a connection between the positive electrode side current collector terminal 30A and the positive electrode 12, or a connection between the negative electrode side current collector terminal and the negative electrode, when a temperature of an electrode body 11 reaches a predetermined temperature.

Description

  The present invention relates to a secondary battery including an electrode body that is formed by insulating a positive electrode and a negative electrode and winding or laminating them.

  For example, Patent Document 1 discloses a secondary battery (storage battery). As shown in FIG. 5, in the storage battery of Patent Document 1, a plurality of positive electrode plates 71 and negative electrode plates 71 are stacked, and each collector terminal 72 is connected to each of the positive electrode plates 71 and the negative electrode plates 71. It has a configuration. The positive electrode plate 71 and the negative electrode plate 71 are formed of a reaction portion 73 to which an active material is applied and a lead portion 74 to which no active material is applied. In FIG. 5, only the configuration on the positive electrode side is shown, and the configuration on the negative electrode side is omitted. In FIG. 5, only the first to fourth electrode plates 71 a, 71 b, 71 c, 71 d among the plurality of electrode plates 71 are illustrated for convenience of explanation.

  First to fourth welding surfaces 72 a, 72 b, 72 c and 72 d are formed on the side surface of the current collecting terminal 72. The first to fourth welding surfaces 72a, 72b, 72c, 72d are at different positions in the direction in which the first to fourth electrode plates 71a, 71b, 71c, 71d are laminated (the direction of the arrow W1 shown in FIG. 5). Has been placed. Further, in the direction orthogonal to the direction in which the first to fourth electrode plates 71a, 71b, 71c, 71d are laminated (the direction of the arrow W2 shown in FIG. 5), the first welding surface 72a and the second welding surface 72b The third welding surface 72c and the fourth welding surface 72d are disposed at different positions. And the 1st electrode plate 71a and the 2nd electrode plate 71b are current collection terminals by bundling the projection part 74a of the lead part 74 of the 1st electrode plate 71a and the 2nd electrode plate 71b, and welding to the 1st welding surface 72a. 72. Similarly, the third electrode plate 71c and the fourth electrode plate 71d are collected by bundling and welding the protrusions 74a of the lead portions 74 of the third electrode plate 71c and the fourth electrode plate 71d to the third welding surface 72c. Connected to terminal 72.

JP-A-9-213299

By the way, such a storage battery may have a problem if the temperature exceeds an allowable range due to heat generation of the first to fourth electrode plates 71a, 71b, 71c, 71d accompanying charging and discharging.
The present invention has been made in order to solve the above-described problems, and an object of the present invention is to provide a secondary battery capable of preventing a problem from occurring due to an electrode body temperature exceeding an allowable range. There is to do.

  In order to achieve the above object, the invention according to claim 1 is provided with an electrode body formed by insulating between the positive electrode and the negative electrode and winding or laminating them, and the positive electrode side current collecting terminal is provided on the positive electrode. Is connected to the negative electrode, and the negative electrode side current collector terminal is connected to the negative electrode, and at least one of the positive electrode side current collector terminal and the positive electrode, or the negative electrode side current collector terminal and the negative electrode When the temperature of the electrode body reaches a predetermined temperature, a connection member that can cut off the connection between the positive current collector terminal and the positive electrode or the connection between the negative current collector terminal and the negative electrode The gist is that they are connected.

  Here, the “predetermined temperature” is a temperature that exists within an allowable range in which the secondary battery does not normally operate at the temperature of the electrode body, and is a temperature that is close to the upper limit within the allowable range. It is. According to this invention, when the temperature of the electrode body reaches a predetermined temperature, the connection between the positive current collector terminal and the positive electrode connected by the connection member or the connection between the negative current collector terminal and the negative electrode is interrupted. Therefore, for example, it is possible to prevent the temperature of the electrode body from rising above a predetermined temperature due to heat generation of the electrode body accompanying charge / discharge. As a result, it is possible to prevent the secondary battery from being defective due to the temperature of the electrode body exceeding the allowable range.

  The invention according to claim 2 is the invention according to claim 1, wherein the connection member is made of a low melting point alloy that melts due to heat of the electrode body when the temperature of the electrode body reaches a predetermined temperature. The gist is that it is formed.

  According to this invention, when the temperature of the electrode body reaches a predetermined temperature, the connection member melts, so that the connection between the positive current collecting terminal and the positive electrode or the connection between the negative current collecting terminal and the negative electrode is made. Can be cut off. Therefore, for example, by cutting the connection member using a cutting means, the positive electrode side current collector terminal is connected to the positive electrode side current collector terminal and the positive electrode or the negative electrode side current collector terminal and the negative electrode are disconnected from each other. The connection between the electric terminal and the positive electrode or the connection between the negative current collecting terminal and the negative electrode can be easily cut off.

  The invention according to claim 3 is the invention according to claim 1, wherein the connecting member is connected to the positive current collector terminal and the positive electrode, or connected to the negative current collector terminal and the negative electrode. In the shut-off state, when the temperature of the electrode body is lowered from a predetermined temperature by a preset temperature, the positive electrode side current collector terminal and the positive electrode, or the negative electrode side current collector terminal and The gist of the present invention is that the negative electrode can be returned from the disconnected state to the connected state.

According to this invention, the secondary battery in which the connection between the positive current collecting terminal and the positive electrode or the connection between the negative current collecting terminal and the negative electrode is once interrupted can be used again.
The gist of the invention of claim 4 is that, in the invention of claim 3, the connecting member is made of a material that can be deformed according to temperature.

  According to this invention, when the temperature of the electrode body reaches a predetermined temperature, the connecting member is deformed by the heat of the electrode body, and the connection between the positive current collecting terminal and the positive electrode or the negative current collecting terminal and the negative electrode Is disconnected. After that, when the temperature of the electrode body is lowered from the predetermined temperature by a preset temperature, the temperature of the connection member also decreases, so that the connection member returns to its original shape, and the positive-side current collector terminal and the positive electrode, Alternatively, the negative current collecting terminal and the negative electrode can be returned from the disconnected state to the connected state. Therefore, when the temperature of the electrode body is lowered from the predetermined temperature by a preset temperature, for example, the return member is used to return the connecting member to the original shape, and the positive electrode side current collecting terminal And positive electrode, or negative electrode current collector terminal and negative electrode are easily disconnected from positive electrode current collector terminal and positive electrode, or negative electrode current collector terminal and negative electrode, compared with the case of returning from the disconnected state to the connected state. The state can be returned to the connected state.

  According to this invention, it can prevent that a malfunction will arise because the temperature of an electrode body exceeds an allowable range.

The longitudinal cross-sectional view of the secondary battery in embodiment. The perspective view which expands and shows a part of electrode body. The perspective view which looked at the main-body part of the positive electrode side current collection terminal from the surface side. Sectional drawing which shows the connection state of a positive electrode side current collection terminal and a positive electrode. The perspective view which shows a part of secondary battery in a prior art example.

Hereinafter, an embodiment embodying the present invention will be described with reference to FIGS.
As shown in FIG. 1, the secondary battery 10 includes an electrode body 11, a case C that houses the electrode body 11, and a lid F of the case C. Case C has a bottomed rectangular box shape with one side opened, and an electrolyte is injected therein. A positive terminal F1 and a negative terminal F2 are attached to the lid F.

  As shown in FIG. 2, the electrode body 11 has a strip-shaped separator 14 interposed between a strip-shaped positive electrode 12 and a strip-shaped negative electrode 13 to insulate the positive electrode 12 and the negative electrode 13 from each other. It is constituted by winding around L in a spiral shape. The positive electrode 12 is made of aluminum, and the negative electrode 13 is made of copper. The positive electrode 12 and the negative electrode 13 are formed with coated portions 12a and 13a to which the active material is applied and uncoated portions 12b and 13b to which the active material is not applied.

  The positive electrode 12 and the negative electrode 13 are stacked while being shifted in the width direction via the separator 14, and the uncoated portions 12 b and 13 b of the positive electrode 12 and the negative electrode 13 are projected outward from both end edges 14 a and 14 b of the separator 14, respectively. In this state, the wire is wound around the winding axis L in a swirl shape. Then, after the positive electrode 12, the negative electrode 13, and the separator 14 are wound in a swirl shape, the flat electrode body 11 is formed by compressing the positive electrode 12, the negative electrode 13, and the separator 14 from both sides in the radial direction. The electrode body 11 includes both bent portions 21 and 22 that are bent so as to be curved in an arc shape located at both ends in the circumferential direction (the direction of the arrow Y1 shown in FIG. 2), and both the bent portions 21 and 22 that extend in the circumferential direction. It is formed from the connection part 23 which connects.

  As shown in FIG. 1, at both ends in the winding axis L direction of the electrode body 11, a positive current collecting terminal 30 </ b> A is connected to the uncoated portion 12 b of the positive electrode 12 forming the connecting portion 23, and the negative electrode 13 A negative current collecting terminal 30B is joined to the uncoated portion 13b.

  Hereinafter, the positive electrode side current collecting terminal 30A bonded to the uncoated portion 12b of the positive electrode 12 will be described in detail. In addition, since the negative electrode side current collection terminal 30B joined to the uncoated part 13b of the negative electrode 13 is the same structure as the positive electrode side current collection terminal 30A joined to the uncoated part 12b of the positive electrode 12, its description Omitted.

  As shown in FIG. 3, the main body portion 30 </ b> C of the positive current collecting terminal 30 </ b> A has a flat plate shape that tapers from the proximal end toward the distal end. The main body portion 30C has a tip portion 301a formed on the tip side thereof, and a first mounting surface 31 and a second mounting surface 32 are formed on both side surfaces of the tip portion 301a. The first mounting surface 31 and the second mounting surface 32 are formed in a flat surface having a rectangular shape when viewed from the side, and extend parallel to each other in the circumferential direction of the electrode body 11 (the direction of the arrow Y1 shown in FIG. 3). .

  The main body portion 30C is formed with a first connecting portion 302a that is connected to the proximal end of the distal end portion 301a. The thickness direction of the layer in the electrode body 11 (shown in FIG. 3) in the state of being inserted between the layers of the uncoated portion 12b on both side surfaces of the first connecting portion 302a from the front end to the base end of the main body portion 30C. A first inclined surface 37 and a second inclined surface 38 are formed so as to be separated from each other in the direction of arrow Z1). The first inclined surface 37 is continuous with the first mounting surface 31, and the second inclined surface 38 is continuous with the second mounting surface 32. Here, the “layer thickness direction in the electrode body 11” refers to the same direction as the direction in which the layers of the uncoated portions 12 b of the positive electrode 12 forming the connecting portion 23 are arranged.

  The main body portion 30C is formed with a central portion 303a that is connected to the base end of the first connecting portion 302a and is located at the center of the main body portion 30C. A third mounting surface 33 and a fourth mounting surface 34 are formed on both side surfaces of the central portion 303a. The third mounting surface 33 and the fourth mounting surface 34 are formed in a flat surface having a rectangular shape in a side view, and extend in parallel to each other in the circumferential direction of the electrode body 11. The third attachment surface 33 is continuous with the first inclined surface 37, and the fourth attachment surface 34 is continuous with the second inclined surface 38.

  The main body part 30C is formed with a second connecting part 304a that is connected to the base end of the central part 303a. The both side surfaces of the second connecting portion 304a are separated from each other in the thickness direction of the layer of the electrode body 11 in a state of being inserted between the layers of the uncoated portion 12b from the distal end to the proximal end of the main body portion 30C. A third inclined surface 39 and a fourth inclined surface 40 that are inclined in this manner are formed. The third inclined surface 39 is continuous with the third mounting surface 33, and the fourth inclined surface 40 is continuous with the fourth mounting surface 34.

  The main body portion 30C is formed with a pair of base end portions 305a and 306a that are connected to the base end of the second connecting portion 304a and are located on the base end side of the main body portion 30C. In each of the base end portions 305a and 306a, a fifth mounting surface 35 and a sixth mounting surface 36 are formed on the outer side surface of the electrode body 11 in the layer thickness direction. The fifth mounting surface 35 and the sixth mounting surface 36 are formed in a flat surface having a rectangular shape in a side view, and extend in parallel to each other in the circumferential direction of the electrode body 11. The fifth attachment surface 35 is continuous with the third inclined surface 39, and the sixth attachment surface 36 is continuous with the fourth inclined surface 40. Further, the side surfaces 41 and 42 facing each other at the base end portions 305a and 306a are spaced apart by a width H9.

  In the thickness direction of the layer in the electrode body 11, the distance H1 between the first mounting surface 31 and the second mounting surface 32, the distance H2 between the first mounting surface 31 and the third mounting surface 33, the third mounting A distance H3 between the surface 33 and the fifth mounting surface 35, a distance H4 between the second mounting surface 32 and the fourth mounting surface 34, and a distance between the fourth mounting surface 34 and the sixth mounting surface 36. H5 is all the same. That is, the first to sixth attachment surfaces 31 to 36 are arranged at equal intervals in the layer thickness direction of the electrode body 11.

  In the circumferential direction of the electrode body 11, the distance H11 between the first mounting surface 31 and the second mounting surface 32 and the third mounting surface 33 and the fourth mounting surface 34 is equal to the third mounting surface 33 and the fourth mounting surface. It is the same as the distance H12 between the surface 34 and the fifth mounting surface 35 and the sixth mounting surface 36. That is, the first mounting surface 31, the second mounting surface 32, the third mounting surface 33, the fourth mounting surface 34, the fifth mounting surface 35, and the sixth mounting surface 36 are equally spaced in the circumferential direction of the electrode body 11. Is arranged.

  A terminal connection portion 45 connected to the positive electrode terminal F1 is provided on the surface 301 that is the surface opposite to the surface on the electrode body 11 side (the uncoated portion 12b side of the positive electrode 12) in the main body portion 30C. . In addition, in the negative electrode side current collection terminal 30B joined to the uncoated part 13b of the negative electrode 13, the terminal connection part 45 provided in the surface 301 of the main-body part 30C is connected to the negative electrode terminal F2.

  First to sixth connection members 51 to 56 as connection members are fixed to the first to sixth attachment surfaces 31 to 36. The first to sixth connection members 51 to 56 have a rectangular plate shape and are formed of a low melting point alloy (an alloy formed by combining indium (In), tin (Sn), and zinc (Zn)). The melting point of this low melting point alloy is about 100 ° C. One end in the longitudinal direction of the first to sixth connecting members 51 to 56 is connected to the first to sixth mounting surfaces 31 to 36, and the other end in the longitudinal direction is not coated with the positive electrode 12 at the positive current collecting terminal 30A. It protrudes toward the uncoated portion 12b side of the positive electrode 12 from the back surface 302 which is the surface on the processed portion 12b side. The width in the short direction of the first to sixth connecting members 51 to 56 is set to a width at which electricity easily flows and melts, and this width is obtained by, for example, experiments.

  As shown in FIG. 4, in each layer of the uncoated portion 12b of the positive electrode 12 forming the connecting portion 23, the uncoated portion 12b is a first to sixth mounting surface 31 corresponding to each layer of the uncoated portion 12b. Are connected to the other ends in the longitudinal direction of the first to sixth connecting members 51 to 56 attached to .about.36. In the present embodiment, it is assumed that the connecting portion 23 is formed from the layers of the uncoated portions 12b of the six positive electrodes 12.

  Specifically, among the layers of the uncoated portion 12b of the positive electrode 12 that forms the connecting portion 23, it is located on the most end side in the layer thickness direction (the direction of the arrow Z1 shown in FIG. 4) in the electrode body 11. The uncoated portion 12 b of the first layer S <b> 1 is connected to the other end side of the fifth connection member 55. Of the layers of the uncoated portion 12b of the positive electrode 12 forming the connecting portion 23, the uncoated portion 12b of the second layer S2 located in the second layer from the one end side in the layer thickness direction of the electrode body 11. Is connected to the other end of the third connecting member 53. Furthermore, among the layers of the uncoated portion 12b of the positive electrode 12 that forms the connecting portion 23, the uncoated portion 12b of the third layer S3 located in the third layer from one end side in the layer thickness direction of the electrode body 11. Is connected to the other end side of the first connecting member 51. Further, among the layers of the uncoated portion 12b of the positive electrode 12 forming the connecting portion 23, the uncoated portion 12b of the fourth layer S4 located in the fourth layer from one end side in the layer thickness direction of the electrode body 11. Is connected to the other end of the second connecting member 52. Furthermore, among the layers of the uncoated portion 12b of the positive electrode 12 forming the connecting portion 23, the uncoated portion 12b of the fifth layer S5 located at the fifth layer from the one end side in the layer thickness direction of the electrode body 11. Is connected to the other end of the fourth connecting member 54. Further, among the layers of the uncoated portion 12b of the positive electrode 12 forming the connecting portion 23, the uncoated portion 12b of the sixth layer S6 located on the other end side in the layer thickness direction of the electrode body 11 is: The sixth connection member 56 is connected to the other end side.

  The other end side of the first to sixth connecting members 51 to 56 and the uncoated portion 12b are irradiated with a laser beam toward the contact portion, so that the contact portion is melted, and these melted portions are re-applied. They are joined together by solidifying. Thereby, the positive electrode side current collecting terminal 30 </ b> A and the uncoated portion 12 b of the positive electrode 12 are connected.

  In addition, since the connection of the negative electrode side current collection terminal 30B and the uncoated part 13b of the negative electrode 13 is the same as the connection of the positive electrode side current collection terminal 30A and the uncoated part 12b of the positive electrode 12, its detailed description Is omitted. For this reason, regarding the connection between the negative electrode side current collecting terminal 30B and the uncoated portion 13b of the negative electrode 13, “positive electrode 12” in the above description is changed to “negative electrode 13” and “positive electrode side current collecting terminal 30A”. Is replaced with “negative electrode side current collecting terminal 30B” and “uncoated part 12b” is replaced with “uncoated part 13b”.

  And while connecting each terminal connection part 45 to the positive electrode terminal F1 or the negative electrode terminal F2, the positive electrode 12 or the negative electrode 13, the positive electrode terminal F1, or the negative electrode terminal F2 via the positive electrode side current collection terminal 30A or the negative electrode side current collection terminal 30B, The secondary battery 10 is configured by housing the electrode body 11 connected to the case C in a case C, and closing and sealing the opening of the case C with a lid F.

Next, the operation of this embodiment will be described.
In the secondary battery 10, the temperature of the electrode body 11 rises due to heat generation of the electrode body 11 due to charge / discharge. The heat of the electrode body 11 is transmitted to the first to sixth connection members 51 to 56. When the temperature of the electrode body 11 reaches a predetermined temperature (about 100 ° C. in the present embodiment), the first to sixth connection members 51 to 56 are melted by the heat of the electrode body 11. Thereby, the connection between the positive current collecting terminal 30A and the positive electrode 12 through the first to sixth connecting members 51 to 56, or the connection between the negative current collecting terminal 30B and the uncoated portions 12b and 13b of the negative electrode 13 is achieved. Is interrupted, and charging / discharging in the secondary battery 10 is not performed.

In the above embodiment, the following effects can be obtained.
(1) When the temperature of the electrode body 11 reaches a predetermined temperature, the positive electrode side current collector terminal 30A and the positive electrode 12 are connected to the positive electrode side current collector terminal 30A and the positive electrode 12, and the negative electrode side current collector terminal 30B and the negative electrode 13. And the negative electrode side current collecting terminal 30B and the negative electrode 13 are connected by first to sixth connecting members 51 to 56, respectively. Therefore, when the temperature of the electrode body 11 reaches a predetermined temperature, the connection between the positive current collecting terminal 30A and the positive electrode 12 connected by the first to sixth connecting members 51 to 56, and the negative current collecting terminal Connection between 30B and the negative electrode 13 is cut off. For this reason, it can prevent beforehand that the temperature of the electrode body 11 rises from predetermined temperature by the heat_generation | fever of the electrode body 11 accompanying charging / discharging. As a result, it is possible to prevent the secondary battery 10 from being defective due to the temperature of the electrode body 11 exceeding the allowable range.

  (2) The 1st-6th connection members 51-56 were formed with the low melting point alloy. Therefore, when the temperature of the electrode body 11 reaches a predetermined temperature, the first to sixth connecting members 51 to 56 are melted, so that the connection between the positive current collecting terminal 30A and the positive electrode 12 and the negative electrode side collecting are performed. The connection between the electrical terminal 30B and the negative electrode 13 can be cut off. Therefore, for example, by cutting the first to sixth connection members 51 to 56 using a cutting means, the connection between the positive electrode side current collector terminal 30A and the positive electrode 12 and the connection between the negative electrode side current collector terminal 30B and the negative electrode 13 are established. Compared with the case where the connection is cut off, the connection between the positive electrode side current collecting terminal 30A and the positive electrode 12 and the connection between the negative electrode side current collecting terminal 30B and the negative electrode 13 can be easily cut off.

  (3) The first to sixth attachment surfaces 31 to 36 are arranged at intervals in the layer thickness direction of the electrode body 11 and at intervals in the circumferential direction of the electrode body 11. First to sixth connection members 51 to 56 connected to the uncoated portion 12 b of the positive electrode 12 or the uncoated portion 13 b of the negative electrode 13 are attached to the sixth attachment surfaces 31 to 36. Therefore, in each layer of the uncoated portion 12b of the positive electrode 12 or the uncoated portion 13b of the negative electrode 13 forming the connecting portion 23, the positive electrode side current collecting terminal 30A, the uncoated portion 12b, the negative electrode side current collecting terminal 30B and the uncoated portion Connection points with the coating part 13b can be dispersed. For this reason, it can suppress that a potential difference arises between the layers of the uncoated part 12b of the positive electrode 12 which forms the connection part 23, or the uncoated part 13b of the negative electrode 13. As a result, the electrode reaction of the positive electrode 12 or the negative electrode 13 forming the connecting portion 23 can be easily made uniform.

In addition, you may change the said embodiment as follows.
In the embodiment, the first to sixth connection members 51 to 56 are arranged in such a manner that the connection between the positive electrode side current collector terminal 30A and the positive electrode 12 and the negative electrode side current collector terminal 30B and the negative electrode 13 is disconnected. When the temperature of 11 is lowered from the predetermined temperature by a preset temperature, the positive current collecting terminal 30A and the positive electrode 12, and the negative current collecting terminal 30B and the negative electrode 13 are connected from the cut-off state. You may make it the structure which can be returned to a state. For example, the first to sixth connecting members 51 to 56 are formed of a material that can be deformed according to the temperature, such as a shape memory alloy or a bimetal. When the temperature of the electrode body 11 reaches a predetermined temperature, the first to sixth connection members 51 to 56 are deformed by the heat of the electrode body 11, and the connection between the positive current collecting terminal 30A and the positive electrode 12 is performed. In addition, the connection between the negative electrode side current collecting terminal 30B and the negative electrode 13 is cut off. Thereafter, when the temperature of the electrode body 11 is lowered from the predetermined temperature by a preset temperature, the temperatures of the first to sixth connection members 51 to 56 themselves also decrease, and thus the first to sixth connection members 51. -56 return to the original shape, and the positive electrode side current collecting terminal 30A and the positive electrode 12 and the negative electrode side current collecting terminal 30B and the negative electrode 13 return from the cut-off state to the connected state. According to this, the secondary battery 10 in which the connection between the positive electrode side current collector terminal 30A and the positive electrode 12 and the connection between the negative electrode side current collector terminal 30B and the negative electrode 13 are once interrupted can be used again. Further, for example, the first to sixth connecting members 51 to 56 are restored to their original shapes by using another return means, and the positive electrode side current collecting terminal 30A and the positive electrode 12, and the negative electrode side current collecting terminal 30B and the negative electrode 13 are restored. Is more easily restored from the disconnected state to the connected state than the positive current collecting terminal 30A and the positive electrode 12, and the negative current collecting terminal 30B and the negative electrode 13 as compared with the case of returning from the disconnected state to the connected state. be able to. When the temperature of the electrode body 11 is lowered from the predetermined temperature by a preset temperature, for example, the first to sixth connecting members 51 to 56 are restored to their original shapes using a return means. The positive current collecting terminal 30A and the positive electrode 12 and the negative electrode current collecting terminal 30B and the negative electrode 13 may be returned from the cut-off state to the connected state.

  In the embodiment, the widths of the first to sixth connection members 51 to 56 may be locally reduced. According to this, when the temperature of the electrode body 11 reaches a predetermined temperature, the first to sixth connection members 51 to 56 can be easily melted from the locally reduced width portion, and the positive electrode side The connection between the current collecting terminal 30A and the positive electrode 12 and the connection between the negative electrode side current collecting terminal 30B and the negative electrode 13 can be quickly cut off.

  In embodiment, you may form so that it may have the urging | biasing force which urges | biases the longitudinal direction other end side of the 1st-6th connection members 51-56 in the direction away from the uncoated parts 12b and 13b. And when welding the 1st-6th connection members 51-56 to uncoated parts 12b and 13b, the longitudinal direction other end side of the 1st-6th connection members 51-56 is uncoated parts 12b and 13b. Weld while pressing against the side. In this way, when the temperature of the electrode body 11 reaches a predetermined temperature, the first to sixth connection members 51 to 56 and the uncoated portions 12b and 13b are disconnected from each other. The sixth connecting members 51 to 56 are vigorously detached so as to jump up in a direction away from the uncoated portions 12b and 13b. Therefore, the connection between the positive electrode side current collecting terminal 30A and the positive electrode 12 and the connection between the negative electrode side current collecting terminal 30B and the negative electrode 13 can be quickly cut off.

  In the embodiment, when the temperature of the electrode body 11 reaches a predetermined temperature, the positive electrode side current collecting terminal 30A and the positive electrode 12 are cut by cutting the first to sixth connecting members 51 to 56 using a cutting means. And the connection between the negative current collecting terminal 30B and the negative electrode 13 may be cut off.

In the embodiment, according to the number of layers of the uncoated portions 12b and 13b, the number of attachment surfaces formed on the main body portion 30C may be further increased, and the number of connection members may be further increased.
In the embodiment, the shape of the main body 30C is not particularly limited. For example, a plate having a thickness instead of a flat plate shape may be used. Further, the distance H1 between the first mounting surface 31 and the second mounting surface 32, the distance H2 between the first mounting surface 31 and the third mounting surface 33, the third mounting surface 33 and the fifth mounting surface 35, , The distance H4 between the second mounting surface 32 and the fourth mounting surface 34, and the distance H5 between the fourth mounting surface 34 and the sixth mounting surface 36 may not be the same. Furthermore, the distance H11 between the first mounting surface 31 and the second mounting surface 32 and the third mounting surface 33 and the fourth mounting surface 34, the third mounting surface 33, the fourth mounting surface 34, and the fifth mounting surface 35. And the distance H12 between the sixth attachment surface 36 may not be the same.

  In the embodiment, the first to sixth connecting members 51 to 56 may be provided only in either the positive electrode side current collecting terminal 30A or the negative electrode side current collecting terminal 30B. Either the positive electrode side current collecting terminal 30A or the negative electrode side current collecting terminal 30B where the first to sixth connecting members 51 to 56 are not provided needs to be in direct contact with the uncoated portions 12b and 13b.

  In the embodiment, for example, among the layers of the uncoated portions 12b and 13b, the uncoated portions 12b and 13b of the first layer S1 and the second layer S2 are bundled to form the first layer S1 and the second layer S2. The uncoated portions 12 b and 13 b may be connected to the fifth connection member 55 attached to the fifth attachment surface 35. That is, you may change suitably the number of the layers of the uncoated parts 12b and 13b connected to the 1st-6th connection members 51-56 attached to the 1st-6th attachment surfaces 31-36.

  In the embodiment, the positive electrode 12 and the negative electrode 13 are stacked while being shifted in the width direction via the separator 14, but the present invention is not limited thereto, and the positive electrode 12 and the negative electrode 13 are stacked via the separator without being shifted in the width direction. May be.

  In the embodiment, the electrode body 11 is used in which the strip-shaped separator 14 is interposed between the strip-shaped positive electrode 12 and the negative electrode 13 and these are wound around the winding axis L in a spiral manner. For example, an electrode body configured by laminating a separator between a positive electrode and a negative electrode may be used.

  DESCRIPTION OF SYMBOLS 10 ... Secondary battery, 11 ... Electrode body, 12 ... Positive electrode, 13 ... Negative electrode, 30A ... Positive electrode side current collection terminal, 30B ... Negative electrode side current collection terminal, 51-56 ... 1st-6th connection member as a connection member .

Claims (4)

An electrode body is formed by insulating between the positive electrode and the negative electrode and winding or laminating them, and a positive current collector terminal is connected to the positive electrode, and a negative current collector terminal is connected to the negative electrode Secondary battery,
At least one of the positive electrode side current collector terminal and the positive electrode, or the negative electrode side current collector terminal and the negative electrode, when the temperature of the electrode body reaches a predetermined temperature, A secondary battery, wherein the secondary battery is connected by a connection member capable of interrupting connection with a positive electrode or connection between the negative-electrode current collector terminal and the negative electrode.   2. The secondary battery according to claim 1, wherein the connection member is formed of a low melting point alloy that is melted by heat of the electrode body when the temperature of the electrode body reaches a predetermined temperature. 3. .   In the connection member, the temperature of the electrode body is set in advance from a predetermined temperature in a state where the connection between the positive current collector terminal and the positive electrode or the connection between the negative current collector terminal and the negative electrode is interrupted. When the temperature is lowered by an amount corresponding to the temperature, the positive current collector terminal and the positive electrode, or the negative current collector terminal and the negative electrode can be returned from the disconnected state to the connected state. The secondary battery according to claim 1, characterized in that:   The secondary battery according to claim 3, wherein the connection member is made of a material that can be deformed according to temperature.

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