Tab and battery cell

Abstract

The utility model provides a tab and a battery cell, the tab comprises a metal belt and tab glue arranged on the metal belt, the ratio of the width of the metal belt to the thickness of the metal belt is more than or equal to 5: 3 and less than or equal to 50: 1, and / or the ratio of the width of the metal belt to the thickness of the metal belt is more than or equal to 1: 1, so that the tab glue can be adhered to the metal belt. And the ratio of the current to the current is smaller than or equal to 500: 1, so that the conductivity of the tab is improved, the current transmission efficiency is improved, the contact resistance is reduced, the heat dissipation capability is enhanced, the risk of local overheating is effectively reduced, and the use safety performance of the battery cell is improved.

Description

Technical Field

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

[0002] Lithium-ion batteries are widely used in consumer electronics, but their safety has become an increasing concern due to their high energy density and thin cell design. In recent years, fires and explosions caused by short circuits, overcharging, and mechanical damage have occurred frequently, making them a key focus of the industry.

[0003] Currently, the main improvement measures for lithium-ion battery short circuit problems are focused on structural optimization and process control. However, under normal temperature short circuit or high temperature short circuit tests, the battery still faces the risk of fire and thermal runaway. Existing improvement measures have not been able to fundamentally solve the short circuit safety problem. Utility Model Content

[0004] This utility model provides a tab and a battery cell to improve the safety performance of the battery cell.

[0005] In a first aspect, embodiments of the present invention provide a tab, comprising:

[0006] Metal strip;

[0007] The tab adhesive is disposed on the metal strip;

[0008] Wherein, the ratio of the width of the metal strip to the thickness of the metal strip is greater than or equal to 5:3 and less than or equal to 50:1, and / or, the ratio of the width of the metal strip to the thickness of the metal strip is greater than or equal to 1:1 and less than or equal to 500:1.

[0009] In one embodiment, the width of the metal strip is greater than or equal to 1 mm and less than or equal to 5 mm.

[0010] In one embodiment, the thickness of the metal strip is greater than or equal to 0.1 mm and less than or equal to 0.6 mm.

[0011] In one embodiment, the thickness of the metal strip is greater than or equal to 0.01 mm and less than or equal to 1 mm.

[0012] In one embodiment, the tab adhesive includes a main body and two extensions located at both ends of the main body, the main body overlapping the metal strip, and the extensions extending from both sides of the main body in the width direction to the outside of the metal strip;

[0013] Wherein, the ratio of the width of the metal strip, the thickness of the metal strip, and the width of the extension is greater than or equal to 5:3:10 and less than or equal to 50:1:5, and / or the ratio of the width of the metal strip, the thickness of the metal strip, and the width of the extension is greater than or equal to 1:1:3 and less than or equal to 500:1:50.

[0014] In one embodiment, the width of the extension is greater than or equal to 0.5 mm and less than or equal to 3 mm.

[0015] In one embodiment, the metal strip is a pure nickel metal strip.

[0016] In one embodiment, the metal strip is a pure aluminum metal strip.

[0017] Secondly, this utility model also provides a battery cell, including the tabs described in any of the above embodiments.

[0018] In one embodiment, the battery cell includes:

[0019] The positive electrode tab includes a first metal strip and a first electrode tab adhesive disposed on the first metal strip;

[0020] The negative electrode tab includes a second metal strip and a second electrode tab adhesive disposed on the second metal strip;

[0021] The first tab adhesive and the second tab adhesive do not overlap.

[0022] The beneficial effects of this embodiment:

[0023] This utility model embodiment provides an electrode tab and a battery cell. The electrode tab includes a metal strip and electrode tab adhesive disposed on the metal strip. By setting the ratio of the width to the thickness of the metal strip to be greater than or equal to 5:3 and less than or equal to 50:1, and / or the ratio of the width to the thickness of the metal strip to be greater than or equal to 1:1 and less than or equal to 500:1, the conductivity of the electrode tab is improved, the current transmission efficiency is increased, the contact resistance is reduced, and the heat dissipation capacity is enhanced, effectively reducing the risk of local overheating, thereby improving the safety performance of the battery cell. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in this embodiment, the accompanying drawings used in the description of the embodiment will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1This is a schematic diagram of the battery structure provided in an embodiment of the present utility model;

[0026] Figure 2 This is a schematic diagram of the electrode tab provided in an embodiment of the present utility model;

[0027] Figure 3 Provided for the embodiments of this utility model Figure 2 Enlarged schematic diagram of region A in the middle;

[0028] Figure 4 Provided for the embodiments of this utility model Figure 2 A schematic diagram of the first type of cross-sectional structure along section B-Bˋ;

[0029] Figure 5 Provided for the embodiments of this utility model Figure 2 A schematic diagram of the second type of cross-sectional structure along section B-Bˋ.

[0030] Explanation of reference numerals in the attached figures:

[0031] 1-Battery; 11-Positive electrode tab; 111-Positive electrode metal strip; 112-First electrode tab adhesive; 12-Negative electrode tab; 121-Negative electrode metal strip; 122-Second electrode tab adhesive; 13-Casing;

[0032] 10-Electrode tab; 101-Metal strip; 102-Electrode tab adhesive; 1021-Main body; 1022-Extension. Detailed Implementation

[0033] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present utility model. In addition, it should be understood that the specific embodiments described herein are only for illustration and explanation of the present utility model and are not intended to limit the present utility model. In the present utility model, unless otherwise stated, directional terms such as "upper" and "lower" generally refer to the upper and lower positions of the device in actual use or operation, specifically the drawing directions in the accompanying drawings; while "inner" and "outer" refer to the outline of the device.

[0034] Please combine Figure 1 , Figure 2 , Figure 3 and Figure 4In one embodiment, the tab 10 includes a metal strip 101 and tab adhesive 102 disposed on the metal strip 101. By reasonably selecting the material of the metal strip 101, the tab 10 can be adapted to serve as the positive tab 11 or negative tab 12 of the battery 1, thereby improving the adaptability and design flexibility of the battery 1.

[0035] Specifically, the metal strip 101 includes, but is not limited to, a pure nickel metal strip or a pure aluminum metal strip. The appropriate metal material can be selected according to the specific application requirements to improve the performance of the tab 10. It is understood that different metal materials have different electrical conductivity, thermal conductivity and mechanical strength, and are suitable for different working environments and usage scenarios.

[0036] Furthermore, the tab 10 is a positive tab 11, and the metal strip 101 is made of pure aluminum, that is, the metal strip 101 is a pure aluminum metal strip.

[0037] Understandably, aluminum has a low density and light weight, while possessing high conductivity, enabling it to effectively conduct current. By using pure aluminum for the metal strip 101, the performance of the battery 1 can be improved. Especially in large-scale battery 1 applications, using pure aluminum metal strips can reduce overall weight and increase energy density, thereby improving the overall performance of the battery 1. At the same time, pure aluminum metal strips have good machinability, allowing for more precise control of shape and size during manufacturing, thus improving production efficiency.

[0038] Please continue to combine Figures 1 to 4 The tab 10 is a positive tab 11. The ratio of the width W1 of the metal strip 101 to the thickness T of the metal strip 101 is greater than or equal to 5:3 and less than or equal to 50:1. By controlling the ratio between the width W1 and the thickness T of the metal strip 101, the conductivity of the positive tab 11 is improved, the current transmission efficiency is increased, the contact resistance is reduced, and the heat dissipation capacity is enhanced, effectively reducing the risk of local overheating.

[0039] Furthermore, the width W1 of the metal strip 101 is greater than or equal to 1 mm and less than or equal to 5 mm, and the thickness T of the metal strip 101 is greater than or equal to 0.1 mm and less than or equal to 0.6 mm. By controlling the ratio between the width W1 and the thickness T of the metal strip 101, the conductivity and thermal conductivity of the metal strip 101 can be improved. This allows the heat generated by the short circuit of the battery 1 during room temperature and high temperature short circuit tests to be rapidly dissipated from the local short circuit point, thereby reducing the local temperature rise and avoiding thermal runaway caused by overheating, thus improving the safety of the battery 1.

[0040] Specifically, the width W1 of the metal strip 101 includes, but is not limited to, 1 mm, 2 mm, 3 mm, 4 mm, and 5 mm, and the thickness T of the metal strip 101 includes, but is not limited to, 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, and 0.6 mm. By controlling the ratio between the width W1 and the thickness T of the metal strip 101, the positive electrode tab 11 has sufficient mechanical strength during ultrasonic spot welding and cell assembly, preventing breakage or deformation of the positive electrode tab 11 during welding or assembly, which would affect production yield and cell consistency. Simultaneously, it also improves the stability of the connection between the positive electrode tab 11 and the cell and external connecting components, meeting the quality control requirements of the battery 1 product in large-scale manufacturing.

[0041] It is understood that, by controlling the ratio between the width W1 and the thickness T of the metal strip 101, this embodiment can reduce the resistance of the positive electrode tab 11, achieve low internal resistance of the positive electrode tab 11, reduce current loss from the positive electrode tab 11 to the inside of the battery 1, improve current transmission efficiency, and thus reduce the overall internal resistance of the battery 1. At the same time, it allows the heat generated by the short circuit of the battery 1 to be quickly conducted and dissipated, enabling the battery 1 to operate stably in both room temperature and high temperature short circuit tests, preventing thermal runaway induced by short circuits. Furthermore, it avoids affecting the performance of other cells due to the adjustment of the size of the positive electrode tab 11, and the design of the metal strip 101 does not increase manufacturing costs, is compatible with existing production processes, and ensures the feasibility of mass production.

[0042] Please combine Figures 1 to 4 In one embodiment, the tab 10 is a positive tab 11, and the tab adhesive 102 includes a main body 1021 and two extensions 1022 located at both ends of the main body 1021. The main body 1021 overlaps with the metal strip 101, and the extensions 1022 extend from both sides of the main body 1021 in the width direction to the outside of the metal strip 101. The ratio of the width W1 of the metal strip 101, the thickness T of the metal strip 101, and the width W2 of the extensions 1022 is greater than or equal to 5:3:10 and less than or equal to 50:1:5, thereby improving the mechanical strength, welding quality, electrical performance, thermal management, and production stability of the battery 1.

[0043] Specifically, the width W2 of the extension 1022 is greater than or equal to 0.5 mm and less than or equal to 3 mm. The width W2 of the extension 1022 includes, but is not limited to, 0.5 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm and 3 mm. By controlling the ratio between the width W1 of the metal strip 101, the thickness T of the metal strip 101 and the width W2 of the extension 1022, the structural stability and mechanical strength of the positive electrode tab 11 during welding and assembly can be improved, preventing welding defects such as incomplete welding, overheating erosion or uneven welding caused by excessively large or small contact area, thereby improving production reliability and the consistency of the battery 1.

[0044] Meanwhile, by controlling the width W2 of the extension 1022, the tab adhesive 102 is more evenly distributed on the metal strip 101, allowing the current to be transmitted more evenly in the welding area, avoiding excessively high local current density, reducing hot spot effects, and improving the stability of current transmission and overall conductivity. Furthermore, it helps to disperse the heat generated during current flow, preventing excessively high local temperatures, thereby reducing the risk of thermal runaway, and thus improving the heat dissipation efficiency of the battery 1, enhancing the safety and long-term reliability of the battery 1.

[0045] Please combine Figure 1 , Figure 2 , Figure 3 and Figure 5 In one embodiment, the tab 10 is a negative tab 12, and the metal strip 101 is made of pure nickel, that is, the metal strip 101 is a pure nickel metal strip.

[0046] Understandably, nickel possesses excellent electrical conductivity, corrosion resistance, and thermal conductivity. By employing pure nickel metal strips, not only can contact resistance be effectively reduced, ensuring stable current transmission, but heat can also be rapidly dispersed when a short circuit occurs in battery 1, reducing the risk of localized overheating and thus improving the safety of battery 1. Simultaneously, pure nickel metal strips have high mechanical strength, making them less prone to breakage or deformation during welding and assembly, thereby improving the production yield and cycle life of battery 1. Furthermore, pure nickel metal strips exhibit excellent corrosion resistance, resisting electrolyte erosion and further enhancing the durability and long-term stability of battery 1.

[0047] Furthermore, the ratio of the width W1 of the metal strip 101 to the thickness T of the metal strip 101 is greater than or equal to 1:1 and less than or equal to 500:1. By controlling the ratio of the width W1 of the metal strip 101 to the thickness T of the metal strip 101, the conductivity and current transmission efficiency of the negative electrode tab 12 are improved, the contact resistance is reduced, and the heat dissipation capacity of the negative electrode tab is enhanced, effectively reducing the risk of local overheating.

[0048] Specifically, the width W1 of the metal strip 101 is greater than or equal to 1 mm and less than or equal to 5 mm, and the thickness T of the metal strip 101 is greater than or equal to 0.01 mm and less than or equal to 1 mm. By controlling the ratio of the width W1 to the thickness T of the metal strip 101, the resistance of the negative electrode tab 12 can be reduced, allowing the current to flow more smoothly, reducing contact resistance and energy loss, and optimizing heat dissipation capability. This reduces the local temperature rise during short circuits or high-current charging and discharging, improves the safety and stability of the battery 1, avoids thermal runaway caused by overheating, and thus improves the safety of the battery 1.

[0049] The width W1 of the metal strip 101 includes, but is not limited to, 1 mm, 2 mm, 3 mm, 4 mm, and 5 mm, and the thickness T of the metal strip 101 includes, but is not limited to, 0.05 mm, 0.07 mm, 0.09 mm, 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, and 1 mm. By controlling the ratio of the width W1 to the thickness T of the metal strip 101, the negative electrode tab 12 has sufficient mechanical strength during ultrasonic spot welding and cell assembly, preventing breakage or deformation of the negative electrode tab 12 during welding or assembly, which would affect production yield and cell consistency. Simultaneously, it also improves the stability of the connection between the negative electrode tab 12 and the cell and external connecting components, meeting the quality control requirements of the battery 1 product in large-scale manufacturing.

[0050] It is understood that, by controlling the ratio of the width W1 to the thickness T of the metal strip 101, this embodiment can reduce the resistance of the positive electrode tab 11, achieve low internal resistance of the positive electrode tab 11, reduce current loss from the positive electrode tab 11 to the inside of the battery 1, improve current transmission efficiency, and thus reduce the overall internal resistance of the battery 1. At the same time, it allows the heat generated by the short circuit of the battery 1 to be quickly conducted and dissipated, enabling the battery 1 to operate stably in both room temperature and high temperature short circuit tests, preventing thermal runaway induced by short circuits. Furthermore, it avoids affecting the performance of other cells due to the adjustment of the size of the positive electrode tab 11, and the design of the metal strip 101 does not increase manufacturing costs, is compatible with existing production processes, and ensures the feasibility of mass production.

[0051] Please combine Figure 1 , Figure 2 , Figure 3 and Figure 5In one embodiment, the tab 10 is a negative tab 12, and the tab adhesive 102 includes a main body 1021 and two extensions 1022 located at both ends of the main body 1021. The main body 1021 overlaps with the metal strip 101, and the extensions 1022 extend from both sides of the main body 1021 in the width direction to the outside of the metal strip 101. The ratio of the width W1 of the metal strip 101, the thickness T of the metal strip 101, and the width W2 of the extensions 1022 is greater than or equal to 1:1:3 and less than or equal to 500:1:50, thereby improving the mechanical strength, welding quality, electrical performance, thermal management, and production stability of the battery 1.

[0052] The width W2 of the extension 1022 is greater than or equal to 0.5 mm and less than or equal to 3 mm. The width W2 of the extension 1022 includes, but is not limited to, 0.5 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm and 3 mm. By controlling the ratio between the width W1 of the metal strip 101, the thickness T of the metal strip 101 and the width W2 of the extension 1022, the structural stability and mechanical strength of the positive electrode tab 11 during welding and assembly can be improved. This prevents welding defects such as incomplete welding, overheating erosion or uneven welding caused by excessively large or small contact areas, thereby improving production reliability and the consistency of the battery 1.

[0053] It should be noted that when the tab 10 is the negative tab 12, the tab adhesive structure used in the negative tab 12 is the same as that of the positive tab 11, including the design of the main body and the extension, the distribution of the tab adhesive on the metal strip, and the width range of the extension. Since the tab adhesive structure of the positive tab 11 has been described in detail in the above embodiments, including its impact on welding stability, current transmission efficiency, heat distribution and battery 1 safety, the tab adhesive structure of the negative tab 12 will not be described again here to avoid redundancy.

[0054] Understandably, the uniform design of the tab adhesive 102 structure helps to improve the consistency of the production process, reduce manufacturing complexity, and ensure the reliability of tabs 10 of different polarities during assembly and use.

[0055] Please combine Figures 1 to 5The battery 1 includes a positive electrode tab 11, a negative electrode tab 12, a battery cell (not shown in the figure), and a casing 13. The casing 13 is used to encapsulate the battery cell, thereby improving the safety and stability of the battery cell. The positive electrode tab 11 and the negative electrode tab 12 are both electrically connected to the battery cell and extend through the casing 13 to the outside of the casing 13, thereby forming the positive and negative electrodes of the battery 1 to facilitate the connection of external circuits.

[0056] Furthermore, the housing 13 is typically made of aluminum-plastic film material to balance lightweight and sealing performance; the tab adhesive 102 is located between the metal strip 101 and the housing 13, thereby playing an insulating and buffering role to prevent the metal strip 101 from directly contacting the housing 13 and causing a short circuit; at the same time, both the metal strip 101 and the tab adhesive 102 extend from the inside of the housing 13 to the outside of the housing 13 to improve the conductivity and structural stability of the battery 1.

[0057] Specifically, the positive electrode tab 11 includes a positive metal strip 111 and a first tab adhesive 112 disposed on the positive metal strip 111, and the negative electrode tab 12 includes a negative metal strip 121 and a second tab adhesive 122 disposed on the negative metal strip 121; wherein the first tab adhesive 112 and the second tab adhesive 122 do not overlap, thereby avoiding the risk of short circuit between the positive electrode tab 11 and the negative electrode tab 12, and improving the safety and stability of the battery 1; at the same time, it can reduce the waste of tab adhesive 102 material, improve the manufacturing process of the battery 1, and improve the overall performance and reliability of the battery 1.

[0058] The specific embodiments of this utility model are illustrated in detail below through specific examples 1, 2, 1, and 2. It can be understood that by comparing the structural and performance differences of different embodiments and comparative examples, the technical advantages and improvement effects of this utility model can be more clearly demonstrated. It should be noted that the following embodiments are only some embodiments of this utility model and are not intended to specifically limit this utility model.

[0059] Example 1 provides a battery 1, which includes a positive electrode tab 11, a negative electrode tab 12, a battery cell, and a casing 13. The positive electrode tab 11 includes a positive electrode metal strip 111 and a second electrode adhesive 122 disposed on the positive electrode metal strip 111. The second electrode adhesive 122 includes a first main body portion and two first extension portions located at both ends of the first main body portion. The negative electrode tab 12 includes a negative electrode metal strip 121 and a second electrode adhesive 122 disposed on the negative electrode metal strip 121. The second electrode adhesive 122 includes a second main body portion and two second extension portions located at both ends of the second main body portion.

[0060] The positive electrode metal strip 111 has a width of 2 mm and a thickness of 0.15 mm, and the first extension has a width of 1 mm; the negative electrode metal strip 121 has a width of 2 mm and a thickness of 0.05 mm, and the first extension has a width of 1 mm.

[0061] Example 2 provides a battery 1, which includes a positive electrode tab 11, a negative electrode tab 12, a battery cell, and a casing 13. The positive electrode tab 11 includes a positive electrode metal strip 111 and a second electrode adhesive 122 disposed on the positive electrode metal strip 111. The second electrode adhesive 122 includes a first main body portion and two first extension portions located at both ends of the first main body portion. The negative electrode tab 12 includes a negative electrode metal strip 121 and a second electrode adhesive 122 disposed on the negative electrode metal strip 121. The second electrode adhesive 122 includes a second main body portion and two second extension portions located at both ends of the second main body portion.

[0062] The positive electrode metal strip 111 has a width of 4 mm and a thickness of 0.3 mm, and the first extension has a width of 2 mm; the negative electrode metal strip 121 has a width of 4 mm and a thickness of 0.07 mm, and the first extension has a width of 2 mm.

[0063] Comparative Example 1 provides a battery 1, which includes a positive electrode tab 11, a negative electrode tab 12, a battery cell, and a casing 13. The positive electrode tab 11 includes a positive electrode metal strip 111 and a second electrode adhesive 122 disposed on the positive electrode metal strip 111. The second electrode adhesive 122 includes a first main body portion and two first extension portions located at both ends of the first main body portion. The negative electrode tab 12 includes a negative electrode metal strip 121 and a second electrode adhesive 122 disposed on the negative electrode metal strip 121. The second electrode adhesive 122 includes a second main body portion and two second extension portions located at both ends of the second main body portion.

[0064] The positive electrode metal strip 111 has a width of 6.5 mm and a thickness of 1 mm, and the first extension has a width of 5 mm; the negative electrode metal strip 121 has a width of 8 mm and a thickness of 1.2 mm, and the first extension has a width of 5 mm.

[0065] Comparative Example 2 provides a battery 1, which includes a positive electrode tab 11, a negative electrode tab 12, a battery cell, and a casing 13. The positive electrode tab 11 includes a positive electrode metal strip 111 and a second electrode adhesive 122 disposed on the positive electrode metal strip 111. The second electrode adhesive 122 includes a first main body portion and two first extension portions located at both ends of the first main body portion. The negative electrode tab 12 includes a negative electrode metal strip 121 and a second electrode adhesive 122 disposed on the negative electrode metal strip 121. The second electrode adhesive 122 includes a second main body portion and two second extension portions located at both ends of the second main body portion.

[0066] The positive electrode metal strip 111 has a width of 4.5 mm and a thickness of 0.8 mm, and the first extension has a width of 3.5 mm; the negative electrode metal strip 121 has a width of 5 mm and a thickness of 1 mm, and the first extension has a width of 3.5 mm.

[0067] It should be noted that the battery structures provided in Example 1, Example 2, Comparative Example 1, and Comparative Example 2 can all be modified. Figure 1 The battery structures shown in Example 1, Example 2, Comparative Example 1, and Comparative Example 2 differ in the different configurations of the tab size and the metal strip size. These differences affect the battery's internal resistance, current transmission efficiency, welding reliability, and thermal management performance and safety under short-circuit conditions.

[0068] Room temperature short-circuit tests were performed on Examples 1, 2, Comparative Example 1, and Comparative Example 2 to evaluate the safety and thermal management performance of different batteries under short-circuit conditions. The method for room temperature short-circuit testing included the following steps: fully charging the test batteries to ensure that all samples were in the same initial state; placing the batteries under experimental conditions of an ambient temperature of 25±3℃ and standard atmospheric pressure; using a battery short-circuit device to connect the positive and negative terminals of the batteries through wires and closing the switch to achieve a short-circuit state.

[0069] It should be noted that this experiment does not restrict the specific signal type of the battery short circuit device, and the resistance of the wires used is controlled at 80±20mΩ to ensure the consistency of the experimental conditions. The cutoff condition of the experiment is set to terminate the test when one of the following two situations occurs: (1) when the battery temperature drops to below 20% of the peak temperature; (2) when the short circuit duration reaches 24 hours. It should be noted that during the experiment, the state of the battery should be closely observed and recorded to determine whether it catches fire or explodes in order to evaluate its short circuit safety performance. The experimental results of Example 1, Example 2, Comparative Example 1 and Comparative Example 2 are shown in Table 1.

[0070] Table 1

[0071] Test Project Test methods Number of tests Number of fires / explosions Pass rate (%) Example 1 Short circuit at room temperature (25℃) 50 0 100％ Example 2 Short circuit at room temperature (25℃) 50 0 100％ Comparative Example 1 Short circuit at room temperature (25℃) 50 50 0％ Comparative Example 2 Short circuit at room temperature (25℃) 50 20 60％

[0072] High-temperature short-circuit tests were conducted on Examples 1, 2, Comparative Example 1, and Comparative Example 2 to evaluate the safety and thermal management performance of different batteries under short-circuit conditions. The method for room-temperature short-circuit testing included the following steps: fully charging the test batteries to ensure that all samples were in the same initial state; placing the batteries in a constant-temperature drying oven at an ambient temperature of 60±2℃ and standard atmospheric pressure to simulate a high-temperature environment; using a battery short-circuit device to connect the positive and negative terminals of the batteries through wires and closing the switch to put the batteries into a short-circuit state.

[0073] It should be noted that this experiment does not restrict the specific signal type of the battery short circuit device, and the resistance of the wires used is controlled at 80±20mΩ to ensure the consistency of the experimental conditions. The cutoff condition of the experiment is set to terminate the test when one of the following two situations occurs: (1) when the battery temperature drops to below 20% of the peak temperature; (2) when the short circuit duration reaches 24 hours. It should be noted that during the experiment, the state of the battery should be closely observed and recorded to determine whether it catches fire or explodes in order to evaluate its short circuit safety performance. The experimental results of Example 1, Example 2, Comparative Example 1 and Comparative Example 2 are shown in Table 2.

[0074] Table 2

[0075] Test Project Test methods Number of tests Number of fires / explosions Pass rate (%) Example 1 High-temperature short circuit (60℃) 50 0 100％ Example 2 High-temperature short circuit (60℃) 50 0 100％ Comparative Example 1 High-temperature short circuit (60℃) 50 50 0％ Comparative Example 2 High-temperature short circuit (60℃) 50 38 24％

[0076] As shown in Tables 1 and 2, compared with the batteries in Comparative Examples 1 and 2, the batteries in Examples 1 and 2 exhibit superior safety and thermal management performance in both room temperature short-circuit and high temperature short-circuit tests. Specifically, the batteries in Examples 1 and 2 did not catch fire or explode during the tests, indicating that their safety under extreme conditions is more reliable. This suggests that the batteries in Examples 1 and 2 are designed to effectively improve the thermal management capabilities of the batteries, thereby reducing safety risks caused by overheating.

[0077] The embodiments of this utility model have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this utility model. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this utility model. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this utility model. Therefore, the content of this specification should not be construed as a limitation of this utility model.

Claims

1. A type of electrode, characterized in that, include: Metal strip; The tab adhesive is disposed on the metal strip; Wherein, the ratio of the width of the metal strip to the thickness of the metal strip is greater than or equal to 5:3 and less than or equal to 50:1, and / or, the ratio of the width of the metal strip to the thickness of the metal strip is greater than or equal to 1:1 and less than or equal to 500:

1.

2. The electrode tab according to claim 1, characterized in that, The width of the metal strip is greater than or equal to 1 mm and less than or equal to 5 mm.

3. The electrode tab according to claim 2, characterized in that, The thickness of the metal strip is greater than or equal to 0.1 mm and less than or equal to 0.6 mm.

4. The electrode tab according to claim 2, characterized in that, The thickness of the metal strip is greater than or equal to 0.01 mm and less than or equal to 1 mm.

5. The electrode tab according to any one of claims 1 to 4, characterized in that, The tab adhesive includes a main body and two extensions located at both ends of the main body. The main body overlaps with the metal strip, and the extensions extend from both sides of the main body in the width direction to the outside of the metal strip. Wherein, the ratio of the width of the metal strip, the thickness of the metal strip, and the width of the extension is greater than or equal to 5:3:10 and less than or equal to 50:1:5, and / or the ratio of the width of the metal strip, the thickness of the metal strip, and the width of the extension is greater than or equal to 1:1:3 and less than or equal to 500:1:

50.

6. The electrode tab according to claim 5, characterized in that, The width of the extension is greater than or equal to 0.5 mm and less than or equal to 3 mm.

7. The electrode tab according to any one of claims 1 to 4, characterized in that, The metal strip is a pure nickel metal strip.

8. The electrode tab according to any one of claims 1 to 4, characterized in that, The metal strip is a pure aluminum metal strip.

9. A battery cell, characterized in that, Includes the tabs as described in any one of claims 1 to 8.

10. The battery cell according to claim 9, characterized in that, The battery cell includes: The positive electrode tab includes a first metal strip and a first electrode tab adhesive disposed on the first metal strip; The negative electrode tab includes a second metal strip and a second electrode tab adhesive disposed on the second metal strip; The first tab adhesive and the second tab adhesive do not overlap.

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