Tab and battery cell

Abstract

The utility model provides a tab and a battery cell, the tab comprises a first tab section, a second tab section and a circuit breaking device, the circuit breaking device is connected in series between the first tab section and the second tab section, the circuit breaking device comprises a first elastic sheet, a second elastic sheet and a temperature change structure, the first elastic sheet is connected with the first tab section, and the second elastic sheet is connected with the second tab section; wherein the temperature change structure is configured to respond to temperature change to change the shape, and when the temperature is not lower than a threshold value, the temperature change structure deforms to drive the second elastic piece to be separated from the first elastic piece; when the temperature is lower than the threshold value, the temperature change structure generates reset deformation, so that the second elastic piece rebounds to abut against the first elastic piece. The battery cell provided by the utility model comprises the tab. According to the tab and the battery cell, the safety performance of the battery cell can be ensured, the battery cell can be reused, and resource waste can be reduced.

Description

Technical Field

[0001] This application relates to the field of battery technology, specifically to a tab and a battery cell. Background Technology

[0002] In the field of battery cell technology, when a battery cell is under high-rate charging and discharging, abnormal charging and discharging, or short-circuited, the cell temperature will rise sharply, potentially leading to serious safety hazards such as fire and explosion. To address this issue, overcurrent-fuse type tabs are currently the primary method. These tabs automatically cut off the circuit when there is an overload, thus ensuring the cell's safety. However, a blown tab will render the cell unusable, resulting in resource waste. Utility Model Content

[0003] This application aims to address at least one of the technical problems existing in the prior art. To this end, this application proposes a tab that enables the reuse of battery cells while ensuring cell safety, thereby reducing the waste of battery cell resources.

[0004] This application also proposes a battery cell having the aforementioned tabs.

[0005] According to an embodiment of this application, the electrode tab includes a first electrode tab segment, a second electrode tab segment, and a circuit breaker device;

[0006] A circuit breaker is connected in series between the first tab section and the second tab section. The circuit breaker includes a first spring, a second spring, and a temperature-changing structure. The first spring is connected to the first tab section, and the second spring is connected to the second tab section.

[0007] The thermochromic structure is configured to change shape in response to temperature changes. When the temperature is not lower than a threshold, the thermochromic structure deforms to drive the second spring to separate from the first spring. When the temperature is lower than the threshold, the thermochromic structure undergoes a reset deformation to allow the second spring to spring back and resist the first spring.

[0008] The tabs according to the embodiments of this application have at least the following beneficial effects: the first tab segment is used to connect the battery cell body, the second tab segment is used to connect the external circuit, and the circuit breaker device is connected in series with the first tab segment and the second tab segment, so that the first tab segment and the second tab segment can be connected through the circuit breaker device. On the one hand, the temperature-changing structure can change shape when the temperature is not lower than the threshold to drive the first spring and the second spring to separate, thereby cutting off the electrical conduction between the first tab segment and the second tab segment, preventing the current from continuing to pass, avoiding serious safety hazards such as fire and explosion that may be caused by overheating of the battery cell, and helping to ensure the safety of the battery cell. On the other hand, the temperature-changing structure can also generate a reset deformation after the temperature is lower than the threshold to release the second spring, so that the second spring can rebound and resist the first spring, realizing the conduction between the first tab segment and the second tab segment, ensuring the reuse of the battery cell after eliminating safety hazards. Thus, while ensuring the safety of the battery cell, it can also improve the utilization rate of resources.

[0009] According to some embodiments of this application, the circuit breaker includes an insulating body with a receiving cavity, a first spring piece connected to the insulating body and a portion of the first spring piece extending into the receiving cavity, a second spring piece connected to the insulating body and a portion of the second spring piece extending into the receiving cavity, and a temperature-changing structure located in the receiving cavity, the temperature-changing structure being connected to the insulating body and spaced apart from the first spring piece.

[0010] When the temperature is below the threshold, the first and second springs abut against each other within the cavity.

[0011] According to some embodiments of this application, the temperature-changing structure includes a first temperature-changing element and a second temperature-changing element, the first temperature-changing element and the second temperature-changing element are stacked, the second temperature-changing element is located on the side of the first temperature-changing element facing the second spring sheet, and the second temperature-changing element is configured to have a coefficient of thermal expansion that is smaller than that of the first temperature-changing element.

[0012] According to some embodiments of this application, the tab also includes a protective adhesive that is connected to and covers the circuit breaker.

[0013] According to some embodiments of this application, along the length direction of the tab, the protective adhesive includes a first protective portion and a second protective portion connected together. The first protective portion covers the circuit breaker, and the second protective portion covers the first tab segment or the second tab segment. Along the width direction of the tab, the width of the first protective portion is smaller than the width of the second protective portion.

[0014] According to some embodiments of this application, along the length direction of the tab, the shortest distance between the edge of the circuit breaker and the edge of the protective adhesive is a, where 1mm≤a≤2mm.

[0015] According to some embodiments of this application, the length of the circuit breaker along the length direction of the tab is b, where 4mm ≤ b ≤ 10mm.

[0016] According to some embodiments of this application, the width of the circuit breaker is c along the width direction of the tab, the width of the tab is d, and the ratio of c to d is 0.5 to 0.75.

[0017] According to some embodiments of this application, the thickness of the circuit breaker is e along the thickness direction of the tab, the thickness of the tab is f, and the ratio of e to f is 0.5 to 0.8.

[0018] The battery cell according to the embodiments of this application includes the tabs in any of the above embodiments.

[0019] The battery cell according to the embodiments of this application has at least the following beneficial effects: the battery cell can cut off power when the temperature exceeds the threshold to ensure electrical safety, and can be re-energized when the temperature is below the threshold to avoid scrapping, which is beneficial to extending the service life of the battery cell and improving the utilization rate of resources.

[0020] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0021] The present application will be further described below with reference to the accompanying drawings and embodiments, wherein:

[0022] Figure 1 This is a schematic diagram of the electrode tab structure in an embodiment of this application;

[0023] Figure 2 This is a partial structural schematic diagram of the electrode tab in an embodiment of this application;

[0024] Figure 3 for Figure 2 Simplified sectional view at point AA;

[0025] Figure 4 This is a schematic diagram of the battery cell structure according to an embodiment of this application;

[0026] Figure 5 This is a schematic diagram of the structure of a battery cell according to another embodiment of this application;

[0027] Figure 6 This is a schematic diagram of the conducting state of the circuit breaker device according to an embodiment of this application;

[0028] Figure 7 This is a schematic diagram of the circuit breaker in the open state according to an embodiment of this application.

[0029] Reference numerals: First electrode segment 110, Second electrode segment 120;

[0030] Circuit breaker 200, first spring 210, second spring 220, insulating body 230, receiving cavity 231, temperature change structure 240, first temperature change element 241, second temperature change element 242;

[0031] Protective adhesive 300, first protective part 310, second protective part 320;

[0032] Battery cell body 400. Detailed Implementation

[0033] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0034] In the description of this application, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0035] In the description of this application, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0036] In the description of this application, unless otherwise expressly defined, terms such as "setup," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this application in conjunction with the specific content of the technical solution.

[0037] In the description of this application, the terms "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0038] The embodiments of this application are described below with reference to the accompanying drawings:

[0039] Reference Figures 1 to 4According to an embodiment of this application, the tab is used to connect with the cell body 400 to form a cell. The tab of this application includes a first tab section 110, a second tab section 120, and a circuit breaker device 200. The first tab section 110 is used to connect to the cell body 400, and the second tab section 120 is used to connect to an external circuit, such as electrically connecting the second tab section 120 to other cells, circuit control boards, or other components. The circuit breaker device 200 is connected in series between the first tab section 110 and the second tab section 120, and the first tab section 110 and the second tab section 120 can be electrically connected through the circuit breaker device 200.

[0040] Reference Figures 5 to 7 The circuit breaker 200 includes a first spring 210, a second spring 220, and a temperature-sensitive structure 240. The first spring 210 is connected to a first tab section 110, and the second spring 220 is connected to a second tab section 120. The temperature-sensitive structure 240 is configured to change shape in response to temperature changes. When the temperature of the temperature-sensitive structure 240 is not lower than a threshold, it can deform to drive the second spring 220 to separate from the first spring 210, thereby cutting off the electrical connection between the first tab section 110 and the second tab section 120. This is to prevent the battery cell from overheating and causing safety hazards, thus ensuring the safety performance of the battery cell. When the temperature of the temperature-sensitive structure 240 is lower than the threshold, it can undergo a reset deformation to cause the second spring 220 to rebound and resist the first spring 210, thereby restoring the electrical conduction between the first tab section 110 and the second tab section 120. This allows the battery cell to continue to be used after the safety hazard has been eliminated, thus improving the utilization rate of battery cell resources.

[0041] Specifically, both the first spring 210 and the second spring 220 have certain elastic deformation properties, and they can elastically counteract each other. The temperature-changing structure 240 can be a composite metal sheet, shape memory alloy, or other structure that can change shape with temperature. Thus, the circuit breaker 200 has two states: a conducting state and a disconnecting state, and the temperature-changing structure 240 has different forms corresponding to these two states. Taking the temperature-changing structure 240 as a composite metal sheet as an example, the composite metal sheet is composed of at least two metal sheets with different coefficients of thermal expansion stacked together. When the temperature of the battery cell rises, it will transfer heat to the temperature-changing structure 240. When the temperature of the temperature-changing structure 240 is greater than or equal to a threshold, the composite metal sheet will bend and deform towards the side with the smaller coefficient of thermal expansion, thereby driving the second spring 220 to undergo elastic deformation and separate from the first spring 210, so as to cut off the electrical conduction between the first tab section 110 and the second tab section 120, terminate the abnormal charging and discharging of the battery cell, and avoid damage to the battery cell.

[0042] When the cell fault is cleared and the cell temperature drops below the threshold, the temperature-changing structure 240 can also generate a reset deformation, causing the second spring 220 to elastically rebound and resist the first spring 210, and the first tab section 110 and the second tab section 120 to reconnect. Therefore, the cell is safer to use and can be reused, which is beneficial to improving resource utilization.

[0043] Reference Figures 5 to 7 In other embodiments, the circuit breaker 200 includes an insulating body 230, a first spring 210, and a second spring 220, all connected to the insulating body 230. A temperature-changing structure 240 is connected to the insulating body 230 and spaced apart from the first spring 210. Therefore, when the temperature-changing structure 240 abuts against the second spring 220, driving the second spring 220 to move, the temperature-changing structure 240 remains insulated from the first spring 210. Thus, by separating the second spring 220 from the first spring 210, the electrical conduction between the first tab section 110 and the second tab section 120 can be cut off. This achieves overheat protection for the battery cell, making electricity use safer. Furthermore, the tabs of this application can remain intact, and after eliminating safety hazards, conduction can be restored, enabling the reuse of the battery cell.

[0044] Reference Figures 5 to 7 In some embodiments, the circuit breaker 200 includes an insulating body 230 with a receiving cavity 231. A first spring 210 is connected to the insulating body 230, and a portion of the first spring 210 extends into the receiving cavity 231. A second spring 220 is connected to the insulating body 230, and a portion of the second spring 220 extends into the receiving cavity 231. A temperature-changing structure 240 is located in the receiving cavity 231, connected to the insulating body 230 and spaced apart from the first spring 210 to ensure that the resistance between the temperature-changing structure 240 and the first spring 210 is broken. When the temperature of the temperature-changing structure 240 is lower than a threshold, the first spring 210 and the second spring 220 elastically abut against each other in the receiving cavity 231. When the temperature of the temperature-changing structure 240 is greater than or equal to the threshold, the temperature-changing structure 240 deforms to drive the second spring 220 to separate from the first spring 210. The receiving cavity 231 is used to block the arc generated during switching, thereby improving the safety of switching on and off.

[0045] Reference Figures 5 to 7In some embodiments, the temperature-changing structure 240 includes a first temperature-changing element 241 and a second temperature-changing element 242, which are stacked together. The first temperature-changing element 241 is connected to the insulating body 230, and the second temperature-changing element 242 is located on the side of the first temperature-changing element 241 facing the second spring 220. The second temperature-changing element 242 is configured to have a lower coefficient of thermal expansion than the first temperature-changing element 241. Thus, when the temperature of the battery cell changes, the temperature-changing structure 240 is heated, and the first temperature-changing element 241 and the second temperature-changing element 242 can expand differently. Since the coefficient of thermal expansion of the first temperature-changing element 241 is greater than that of the second temperature-changing element 242, when the temperature exceeds a threshold, the temperature-changing structure 240 will bend towards the side of the second temperature-changing element 242, thereby driving the second spring 220 and timely cutting off the contact between the first spring 210 and the second spring 220. While ensuring electrical safety, damage to the electrode tab is avoided, thus allowing the battery cell to be reused.

[0046] Specifically, when the temperature is below the threshold, the first spring 210 and the second spring 220 abut against each other. The first temperature-sensitive element 241 can be copper, and the second temperature-sensitive element 242 can be iron, arranged in a stacked manner. When the temperature exceeds the threshold, both the first temperature-sensitive element 241 and the second temperature-sensitive element 242 will expand, with the first temperature-sensitive element 241 expanding more than the second temperature-sensitive element 242. Therefore, the temperature-sensitive structure 240 will bend towards the side where the second temperature-sensitive element 242 is located, thereby abutting against the second spring 220 to drive the second spring 220 to separate from the first spring 210, achieving a circuit break to protect the battery cell. Furthermore, when the safety hazard is eliminated and the temperature is below the threshold, the temperature-sensitive structure 240 undergoes a reset deformation, and the second spring 220 elastically resets and abuts against the first spring 210 again to conduct the first tab section 110 and the second tab section 120. The battery cell can be reused, which is beneficial for resource conservation.

[0047] Reference Figure 1 and Figure 2In some embodiments, the tab also includes a protective adhesive 300, which is connected to and covers the circuit breaker 200. The protective adhesive 300 can be made of an insulating material. On one hand, the protective adhesive 300 covers the solder joints between the circuit breaker 200 and the first tab section 110, and also covers the solder joints between the circuit breaker 200 and the second tab section 120, effectively preventing solder burrs from piercing the cell body 400 or the protective film, thus ensuring the integrity of the cell and making its use safer. On the other hand, the coverage of the protective adhesive 300 helps conduct heat to the circuit breaker 200, allowing the circuit breaker 200 to more sensitively sense changes in the cell temperature, thereby achieving more timely and accurate circuit switching control. That is, when the cell temperature rises abnormally, the circuit breaker 200 can respond more quickly to cut off the circuit, preventing damage to the cell due to overheating; when the temperature returns to normal, it can promptly restore the circuit, ensuring the normal operation of the cell.

[0048] Reference Figure 1 and Figure 2 In some embodiments, along the length of the tab, the protective adhesive 300 includes a first protective portion 310 and a second protective portion 320 connected together. The first protective portion 310 covers the circuit breaker 200, and the second protective portion 320 covers the first tab segment 110 or the second tab segment 120. Along the width of the tab, the width of the first protective portion 310 is smaller than the width of the second protective portion 320. The first protective portion 310 is used to seal the circuit breaker 200 and also facilitates heat conduction to the circuit breaker 200, enabling the temperature-changing structure 240 to respond more promptly to temperature changes in the battery cell, thereby improving electrical safety. The second protective portion 320 covers the tab and corresponds to the sealing edge of the battery cell, effectively preventing tab burrs from damaging the battery cell encapsulation and improving the battery cell's sealing performance.

[0049] Reference Figure 1 and Figure 4 In some embodiments, the shortest distance between the edge of the circuit breaker 200 and the edge of the protective adhesive 300 along the length of the tab is 'a', where 1mm ≤ a ≤ 2mm. Defining the lower limit of the shortest distance 'a' ensures that the protective adhesive 300 covers the circuit breaker 200, preventing the sealing edge from contacting exposed solder joints and causing poor cell sealing. Defining the upper limit of the shortest distance 'a' helps reduce production costs. Therefore, limiting the range of values ​​for the shortest distance 'a' allows for a better balance between cell performance and cost.

[0050] Specifically, the shortest distance 'a' can be set to any length of 1.0mm, 1.2mm, 1.4mm, 1.6mm, 1.8mm, or 2mm, or any length value within the range of 1mm to 2mm. Alternatively, it can be any two values ​​of 1.0mm, 1.2mm, 1.4mm, 1.6mm, 1.8mm, or 2mm as endpoints to form a range value, thereby further optimizing the size of the protective adhesive 300. While ensuring the performance of the battery cell, the space occupied by the protective adhesive 300 is reduced, and the structure of the tab is more compact.

[0051] Reference Figures 1 to 3 In other embodiments, with the length direction of the tab as the axis, the protective adhesive 300 is wrapped around the circuit breaker 200 to seal the circuit breaker 200. This helps to further improve the sealing performance of the circuit breaker 200 and provide heat conduction to the circuit breaker 200 more effectively, so that the circuit breaker 200 can sense the temperature change of the battery cell more promptly.

[0052] Reference Figure 1 and Figure 2 In some embodiments, the length of the circuit breaker 200 along the length direction of the tab is b, and 4mm ≤ b ≤ 10mm. For example, the length of the circuit breaker 200 can be set to 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, or 10mm, or any length value from 4mm to 10mm. Furthermore, any two values ​​from 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, and 10mm can be selected as endpoints to form a range value, further optimizing the length of the circuit breaker 200. A lower limit on the length of the circuit breaker 200 is defined to prevent it from being too short and difficult to manufacture, while an upper limit on the length of the circuit breaker 200 is defined to avoid affecting the battery cell packaging and to ensure the current carrying capacity of the circuit breaker 200.

[0053] Reference Figures 5 to 7 In other embodiments, along the length of the tab, a portion of the first spring 210 and a portion of the second spring 220 are exposed outside the insulating body 230. The exposed portions of both the first spring 210 and the second spring 220 are welded portions, meaning the circuit breaker 200 includes two welded portions. Along the length of the tab, the insulating body 230 is located between the two welded portions. To ensure the stability of the connection between the circuit breaker 200 and the two tab segments, the ratio of the length of the insulating body 230 to the length of the welded portion is 0 (excluding) to 1.5. Therefore, while limiting the size of the circuit breaker 200, a better balance can be struck between the manufacturing difficulty and welding difficulty of the circuit breaker 200, making the tab in this application easier to manufacture.

[0054] Reference Figures 1 to 3In some embodiments, along the width direction of the tab, the width of the circuit breaker 200 is c, and the width of the tab is d (which can be understood as the width of the first tab segment 110 and / or the second tab segment 120). The ratio of c to d is 0.5 to 1. The lower limit of this ratio is defined to ensure the manufacturability and current carrying capacity of the circuit breaker 200. The upper limit of this ratio is defined to prevent the circuit breaker 200 from exceeding the width of the tab, thereby preventing the circuit breaker 200 from adversely affecting the cell thickness in the area outside the tab and ensuring the flatness of the cell.

[0055] Specifically, the ratio of c to d can be set to 0.5, 0.6, 0.7, 0.8, 0.9 or 1, or any value between 0.5 and 1. Alternatively, any two values ​​among 0.5, 0.6, 0.7, 0.75, 0.8, 0.9 or 1 can be used as endpoints to form a range value. For example, the ratio of c to d can be between 0.5 and 0.75 to better balance the performance of the circuit breaker 200 with the width ratio of the tab.

[0056] Reference Figures 1 to 3 In other embodiments, the width of the welded portion is not less than two-thirds of the width of the insulating body 230 along the width direction of the tabs, so as to ensure the welding strength between the circuit breaker 200 and the two tab segments.

[0057] Reference Figures 1 to 3 In some embodiments, along the thickness direction of the tab, the thickness of the circuit breaker 200 is e, and the thickness of the tab is f. The ratio of e to f is 0.5 to 0.8. The lower limit of this thickness ratio is set to make the circuit breaker 200 easy to manufacture and to ensure the normal switching function of the circuit breaker 200. The upper limit of this thickness ratio is set to prevent the circuit breaker 200 from protruding locally, so that the tab is flatter.

[0058] Specifically, the aforementioned thickness ratio can be set to any ratio of 0.5, 0.6, 0.7, or 0.8, or any value between 0.5 and 0.8, or a range of any two values ​​among 0.5, 0.6, 0.7, and 0.8 as endpoint values, in order to better optimize the structure of the tab.

[0059] Reference Figures 1 to 3 In other embodiments, the protective adhesive 300 covers the circuit breaker 200, and the upper limit of the thickness ratio is used to ensure that the protective adhesive 300 covers the circuit breaker 200 and to prevent the protective adhesive 300 from protruding additionally, so that the tab is flatter.

[0060] Reference Figures 1 to 3In other embodiments, the protective adhesive 300 covers the circuit breaker 200. Along the width direction of the tab, the width of the circuit breaker 200 does not exceed the width of any tab segment. The protective adhesive 300 located on any side of the circuit breaker 200 extends beyond the edge of the tab segment to ensure full coverage of the circuit breaker 200.

[0061] refer to Figure 4 The battery cell according to the embodiments of this application includes the tabs in any of the above embodiments. The tabs are connected to the battery cell body 400 to form the battery cell. Thus, the battery cell in this application can cut off the power in time when subjected to abnormal high temperature, so as to avoid the danger of fire, explosion and other hazards. This is beneficial to fully ensure the safety of the battery cell. Moreover, after the battery cell fault is eliminated, the power can be restored, so as to ensure the reuse of the battery cell and reduce the waste of resources.

[0062] Specifically, the battery cell is encapsulated by an aluminum-plastic film, and the circuit breaker 200 is located outside the encapsulation cavity surrounded by the aluminum-plastic film. The second protection part 320 corresponds to the sealing edge of the aluminum-plastic film. The heat of the battery cell can be conducted to the circuit breaker 200, which can cut off or connect the tabs to realize the power supply control of the battery cell.

[0063] Reference Figure 5 In other embodiments, the circuit breaker 200 is located inside the encapsulation cavity, and the cell body 400 includes an electrode with a groove. The circuit breaker 200 is placed in the groove, thereby enabling the circuit breaker 200 to cut off the circuit more promptly according to the temperature change of the cell, making the use of electricity safer. In addition, the groove accommodates the circuit breaker 200, making the cell more flat.

[0064] The embodiments of this application have been described in detail above with reference to the accompanying drawings. However, this application is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of this application. Furthermore, unless otherwise specified, the embodiments and features described in the embodiments of this application can be combined with each other.

Claims

1. A tab, characterized in that, include: First pole ear segment; Second pole ear segment; A circuit breaker is connected in series between the first tab section and the second tab section. The circuit breaker includes a first spring, a second spring, and a temperature-changing structure. The first spring is connected to the first tab section, and the second spring is connected to the second tab section. The temperature-changing structure is configured to change shape in response to temperature changes. When the temperature is not lower than a threshold, the temperature-changing structure deforms to drive the second spring to separate from the first spring. When the temperature is lower than the threshold, the temperature-changing structure undergoes a reset deformation to cause the second spring to rebound and abut against the first spring.

2. The electrode tab according to claim 1, characterized in that, The circuit breaker includes an insulating body with a receiving cavity. A first spring is connected to the insulating body, and a portion of the first spring extends into the receiving cavity. A second spring is connected to the insulating body, and a portion of the second spring extends into the receiving cavity. A temperature-changing structure is located inside the receiving cavity and is connected to the insulating body and spaced apart from the first spring. When the temperature is below the threshold, the first and second springs abut against each other within the receiving cavity.

3. The electrode tab according to claim 1, characterized in that, The temperature-changing structure includes a first temperature-changing element and a second temperature-changing element, the first temperature-changing element and the second temperature-changing element are stacked, the second temperature-changing element is located on the side of the first temperature-changing element facing the second spring sheet, and the second temperature-changing element is configured to have a coefficient of thermal expansion that is smaller than that of the first temperature-changing element.

4. The electrode tab according to claim 1, characterized in that, The electrode tab also includes a protective adhesive, which is connected to and covers the circuit breaker.

5. The electrode tab according to claim 4, characterized in that, Along the length of the tab, the protective adhesive includes a first protective part and a second protective part connected together. The first protective part covers the circuit breaker, and the second protective part covers either the first tab segment or the second tab segment. Along the width of the tab, the width of the first protective part is smaller than the width of the second protective part.

6. The electrode tab according to claim 4, characterized in that, Along the length of the tab, the shortest distance between the edge of the circuit breaker and the edge of the protective adhesive is a, where 1mm ≤ a ≤ 2mm.

7. The electrode tab according to claim 1, characterized in that, Along the length direction of the electrode tab, the length of the circuit breaker is b, where 4mm ≤ b ≤ 10mm.

8. The electrode tab according to claim 1, characterized in that, Along the width direction of the tab, the width of the circuit breaker is c, the width of the tab is d, and the ratio of c to d is 0.5 to 1.

9. The electrode tab according to claim 1, characterized in that, Along the thickness direction of the tab, the thickness of the circuit breaker is e, the thickness of the tab is f, and the ratio of e to f is 0.5 to 0.

8.

10. A battery cell, characterized in that, Includes the tabs according to any one of claims 1 to 9.

Images