Tab assembly, battery and electric equipment

Abstract

The utility model belongs to the technical field of batteries, and particularly relates to a pole lug assembly, a battery and electric equipment, the pole lug assembly comprises a pole lug main body and pole lug glue arranged on the pole lug main body, the pole lug main body comprises a first conducting layer, a second conducting layer and a polymer layer, the polymer layer is arranged between the first conductive layer and the second conductive layer; the first conductive layer and the second conductive layer effectively ensure the conductive performance of the tab assembly, so that the current can flow between the interior of the battery and an external circuit; and the polymer layer has high temperature resistance and corrosion resistance, and is better in tensile strength and ductility, so that the bending resistance of the tab assembly is effectively improved, the breakage probability of the tab assembly is reduced, the mechanical test passing rate of the tab assembly is improved, the service life of the tab assembly is prolonged, and the safety and reliability of the battery are further improved.

Description

Technical Field

[0001] This utility model belongs to the technical field of batteries, specifically relating to electrode assemblies, batteries, and electrical devices. Background Technology

[0002] Lithium-ion batteries, as a new type of rechargeable battery, have advantages such as high energy density and power density, high operating voltage, light weight, small size, long cycle life, good safety, and environmental friendliness. They have broad application prospects in portable electrical appliances, power tools, large-scale energy storage, and electric transportation power supplies.

[0003] In existing technologies, electrode tabs are generally made of aluminum, nickel, or copper. However, these tabs have certain limitations in terms of folding resistance. During mechanical testing, these tabs are easily damaged during bending and are prone to breakage after repeated folding. This shortens the lifespan of the tabs and reduces the safety and reliability of the battery. Utility Model Content

[0004] The purpose of this utility model is to address the shortcomings of the existing technology by providing a tab assembly, a battery, and an electrical device, thereby solving the technical problems of poor folding resistance, easy bending and damage, and easy breakage of the tab after repeated folding in the existing technology.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] In a first aspect, the present invention provides an electrode assembly, including an electrode body and an electrode adhesive disposed on the electrode body. The electrode body includes a first conductive layer, a second conductive layer and a polymer layer, wherein the polymer layer is disposed between the first conductive layer and the second conductive layer.

[0007] In some embodiments, the thickness F of the first conductive layer and the thickness J of the polymer layer satisfy the relationship: F≤J;

[0008] And / or, the thickness G of the second conductive layer and the thickness J of the polymer layer satisfy the relationship: G≤J.

[0009] In some embodiments, the thickness F of the first conductive layer satisfies the following relationship: 1μm≤F≤200μm;

[0010] And / or, the thickness G of the second conductive layer satisfies the relationship: 1μm≤G≤200μm.

[0011] In some embodiments, the thickness F of the first conductive layer and the thickness G of the second conductive layer satisfy the relationship: F ​​= G;

[0012] Or, F > G;

[0013] Or, F < G.

[0014] In some embodiments, the thickness J of the polymer layer satisfies the relationship: 1μm≤J≤200μm.

[0015] In some embodiments, the first conductive layer is an aluminum layer, a nickel layer, a copper layer, a copper-aluminum alloy layer, a copper-nickel alloy layer, an aluminum-nickel alloy layer, or a copper-aluminum-nickel alloy layer.

[0016] And / or, the second conductive layer is an aluminum layer, a nickel layer, a copper layer, a copper-aluminum alloy layer, a copper-nickel alloy layer, an aluminum-nickel alloy layer, or a copper-aluminum-nickel alloy layer.

[0017] In some embodiments, the first conductive layer and the second conductive layer are the same type of metal layer or alloy layer.

[0018] In some embodiments, the polymer layer is a polypropylene layer, a polyethylene terephthalate layer, or a polyimide layer.

[0019] Secondly, this utility model provides a battery, including an aluminum-plastic film and a battery cell. The aluminum-plastic film has a accommodating cavity, and the battery cell includes a battery cell body and the aforementioned tab assembly. The tab assembly is disposed at one end of the battery cell body, and the tab assembly extends partially beyond the aluminum-plastic film.

[0020] Thirdly, this utility model provides an electrical device, including the aforementioned battery.

[0021] Compared with the prior art, the beneficial effects achieved by this utility model are as follows:

[0022] This utility model discloses a tab assembly that utilizes a tab body and tab adhesive in conjunction. The tab adhesive is disposed on the tab body, which includes a first conductive layer, a second conductive layer, and a polymer layer. The first and second conductive layers effectively ensure the conductivity of the tab assembly, thereby guaranteeing the flow of current between the battery's internal and external circuits. The polymer layer, disposed between the first and second conductive layers, possesses high-temperature resistance, corrosion resistance, and excellent tensile strength and ductility, effectively improving the tab assembly's bending resistance. This reduces the probability of tab assembly breakage, increases the mechanical test pass rate, extends the lifespan of the tab assembly, and ultimately enhances the battery's safety and reliability.

[0023] Additional aspects and advantages of this invention 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 the invention. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art 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 1 This is one of the structural schematic diagrams of the electrode assembly of this utility model.

[0026] Figure 2 This is the second structural schematic diagram of the electrode assembly of this utility model.

[0027] The reference numerals in the attached figures are explained as follows:

[0028] 100. Electrode assembly;

[0029] 10. Electrode body; 11. First conductive layer; 12. Second conductive layer; 13. Polymer layer;

[0030] 20. Ear gel. Detailed Implementation

[0031] If certain terms are used in the specification and claims to refer to specific components, those skilled in the art will understand that hardware manufacturers may use different names to refer to the same component. This specification and claims do not distinguish components based on differences in name, but rather on differences in function. The term "comprising" as used throughout the specification and claims is an open-ended term and should be interpreted as "comprising but not limited to." "Approximately" means that within an acceptable margin of error, those skilled in the art can solve the technical problem and substantially achieve the technical effect within a certain margin of error.

[0032] Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be interpreted as indicating or implying relative importance.

[0033] In this invention, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this invention, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0034] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0035] The following will be combined with the appendix Figures 1-2 The technical solutions in the embodiments of this utility model are clearly and completely described. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of this utility model.

[0036] The electrical equipment described in this utility model embodiment includes a battery. The electrical equipment can be automobiles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, and power tools, etc. Automobiles can be gasoline-powered vehicles, natural gas-powered vehicles, or new energy vehicles; new energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc.; spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc.; electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc.; power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc. This application embodiment does not impose any special limitations on the above-mentioned electrical equipment.

[0037] The battery of this utility model embodiment includes an aluminum-plastic film and a battery cell. The aluminum-plastic film has a accommodating cavity. The battery cell includes a battery cell body and a tab assembly 100. The tab assembly 100 is disposed at one end of the battery cell body and extends partially outside the aluminum-plastic film.

[0038] Please see Figures 1-2 The tab assembly 100 of this utility model includes a tab body 10 and a tab adhesive 20 disposed on the tab body 10. The tab body 10 includes a first conductive layer 11, a second conductive layer 12 and a polymer layer 13, with the polymer layer 13 disposed between the first conductive layer 11 and the second conductive layer 12.

[0039] Compared with the prior art, the tab assembly 100 of this utility model embodiment, through the cooperative use of the tab body 10 and the tab adhesive 20, with the tab adhesive 20 disposed on the tab body 10, includes a first conductive layer 11, a second conductive layer 12, and a polymer layer 13. The first conductive layer 11 and the second conductive layer 12 effectively ensure the conductivity of the tab assembly 100, thereby ensuring that current can flow between the internal and external circuits of the battery. The polymer layer 13 is disposed between the first conductive layer 11 and the second conductive layer 12. The polymer layer 13 has high temperature resistance, corrosion resistance, and good tensile strength and ductility, effectively improving the bending resistance of the tab assembly 100, thereby reducing the probability of the tab assembly 100 breaking, improving the mechanical test pass rate of the tab assembly 100, extending the service life of the tab assembly 100, and thus improving the safety and reliability of the battery.

[0040] Understandably, in order to reduce the resistivity difference between the first conductive layer 11 and the second conductive layer 12, the tab body 10 is provided with a through-hole structure penetrating the first conductive layer 11, the polymer layer 13, and the second conductive layer 12, and the through-hole structure is filled with a conductive material. Specifically, the conductive material can be the same material as the first conductive layer 11 and the second conductive layer 12; or the conductive material can be a different material from the first conductive layer 11 and the second conductive layer 12. For example, the conductive material is carbon black, carbon nanotubes, graphite, acetylene black, graphene, nickel, iron, copper, aluminum, or an alloy.

[0041] In some embodiments, the first conductive layer 11 is an aluminum layer, a nickel layer, a copper layer, a copper-aluminum alloy layer, a copper-nickel alloy layer, an aluminum-nickel alloy layer, or a copper-aluminum-nickel alloy layer; and / or, the second conductive layer 12 is an aluminum layer, a nickel layer, a copper layer, a copper-aluminum alloy layer, a copper-nickel alloy layer, an aluminum-nickel alloy layer, or a copper-aluminum-nickel alloy layer. By providing the first conductive layer 11 and the second conductive layer 12, and making the first conductive layer 11 and / or the second conductive layer 12 an aluminum layer, a nickel layer, a copper layer, a copper-aluminum alloy layer, a copper-nickel alloy layer, an aluminum-nickel alloy layer, or a copper-aluminum-nickel alloy layer, the selectivity of the first conductive layer 11 and the second conductive layer 12 is effectively increased.

[0042] Specifically, the aluminum layer has good conductivity and low cost; the nickel layer has stable conductivity and a certain degree of corrosion resistance; the copper layer has better conductivity than both aluminum and nickel. By selecting different materials or combinations, the conductivity of the tab assembly 100 can be optimized to meet the needs of different application scenarios.

[0043] Furthermore, copper-aluminum alloy layers, copper-nickel alloy layers, aluminum-nickel alloy layers, or copper-aluminum-nickel alloy layers can fully utilize the advantages of each material to create a complementary effect. For example, a copper-aluminum alloy layer combines the high conductivity of copper with the lightweight and high strength of aluminum, allowing the tab assembly 100 to maintain conductivity while reducing weight and improving overall performance. A copper-nickel alloy layer combines the high conductivity of copper with the corrosion resistance of nickel, allowing the tab assembly 100 to maintain conductivity while also being corrosion resistant. A nickel-aluminum alloy layer combines the corrosion resistance of nickel with the lightweight and conductivity of aluminum, allowing the tab assembly 100 to maintain conductivity while reducing weight and increasing corrosion resistance.

[0044] In some embodiments, the first conductive layer 11 and the second conductive layer 12 are of the same type of metal or alloy layer. By using the first conductive layer 11 and the second conductive layer 12 together, since they are of the same type of metal or alloy layer, they can be manufactured using the same production processes and equipment, thereby simplifying the production process and improving production efficiency. Simultaneously, the use of the same type of metal or alloy layer for the first conductive layer 11 and the second conductive layer 12 reduces the types of materials and processing steps, helping to lower manufacturing costs. Furthermore, the identical structure of the first conductive layer 11 and the second conductive layer 12 means that their key parameters such as material composition, thickness, and resistivity are consistent, thus ensuring the stability of conductivity and reducing the likelihood of performance degradation due to material differences or processing errors during long-term use, thereby improving the reliability and service life of the tab assembly 100.

[0045] It is understandable that since the first conductive layer 11 and the second conductive layer 12 are of the same type of metal or alloy layer, their materials are always consistent. For example, when the first conductive layer 11 is an aluminum layer, the second conductive layer 12 is also an aluminum layer; when the first conductive layer 11 is a nickel layer, the second conductive layer 12 is also a nickel layer; and when the first conductive layer 11 is a copper-aluminum alloy layer, the second conductive layer 12 is also a copper-aluminum alloy layer.

[0046] In some embodiments, the polymer layer 13 is a polypropylene layer, a polyethylene terephthalate layer, or a polyimide layer. By providing the polymer layer 13, the variety of choices for the polymer layer 13 is effectively increased by making the polymer layer 13 a polypropylene (PP) layer, a polyethylene terephthalate (PET) layer, or a polyimide (PI) layer.

[0047] Specifically, the polypropylene layer, polyethylene terephthalate layer, and polyimide layer all have good corrosion resistance and high temperature resistance, as well as good tensile strength and ductility, which effectively improves the bending resistance of the tab assembly 100, thereby reducing the probability of the tab assembly 100 breaking, improving the mechanical test pass rate of the tab assembly 100, extending the service life of the tab assembly 100, and thus improving the safety and reliability of the battery.

[0048] The inventors discovered that the excessive thickness of the aluminum, nickel, and copper tabs creates significant gaps between the tab adhesive 20 and the aluminum-plastic film after battery encapsulation. This not only increases the risk of battery leakage during drop tests but also, due to their thickness, causes them to protrude noticeably from the surrounding electrode plates when connected to the cell body, occupying more internal space. During compression tests, this protrusion leads to higher localized pressure in that area, increasing the risk of current collector tearing and potentially causing cell failure.

[0049] Therefore, the tab assembly 100 of this utility model, by setting the thickness F of the first conductive layer 11, the thickness G of the second conductive layer 12, and the thickness J of the polymer layer 13, reduces the overall thickness of the tab assembly 100 while ensuring the structural strength and good conductivity of the tab assembly 100. This effectively reduces the gap between the tab adhesive 20 and the aluminum-plastic film after battery encapsulation, thereby reducing the risk of battery leakage during drop tests. Simultaneously, the smaller thickness of the tab assembly 100 effectively reduces the height of the tab assembly 100 protruding from the cell body, improving the surface flatness of the cell. This results in more uniform local pressure on the tab assembly 100 during compression tests, effectively preventing the current collector from tearing due to excessive pressure.

[0050] In addition, the polymer layer 13 not only effectively improves the bending resistance of the tab assembly 100, but also provides a certain buffering effect when the tab assembly 100 is squeezed, disperses and reduces local pressure, and effectively prevents the current collector from tearing due to excessive pressure, thereby improving the safety and reliability of the battery.

[0051] Please see Figure 2In some embodiments, the thickness F of the first conductive layer 11 and the thickness J of the polymer layer 13 satisfy the relationship: F ​​≤ J; and / or, the thickness G of the second conductive layer 12 and the thickness J of the polymer layer 13 satisfy the relationship: G ≤ J. By setting the thickness F of the first conductive layer 11, the thickness G of the second conductive layer 12, and the thickness J of the polymer layer 13, such that the thickness F of the first conductive layer 11 is less than the thickness J of the polymer layer 13 (i.e., F < J), and the thickness G of the second conductive layer 12 is less than the thickness J of the polymer layer 13 (i.e., G < J), the thickness F of the first conductive layer 11 and the thickness G of the second conductive layer 12 are effectively reduced, resulting in smaller burrs formed after the tab assembly 100 breaks, thereby effectively avoiding puncture of the separator and short circuit of the battery cell. When the thickness F of the first conductive layer 11, the thickness G of the second conductive layer 12, and the thickness J of the polymer layer 13 are all the same (i.e., F = G = J), the overall structure of the tab assembly 100 will be more uniform when the thicknesses are all the same, which to some extent helps to simplify the manufacturing process and improve production efficiency. In addition, a uniform thickness may allow for a more even distribution of stress when the component is subjected to external forces, thereby improving the overall mechanical strength to some extent.

[0052] Please see Figure 2 In some embodiments, the thickness F of the first conductive layer 11 satisfies the relationship: 1μm≤F≤200μm; and / or, the thickness G of the second conductive layer 12 satisfies the relationship: 1μm≤G≤200μm.

[0053] The thickness F of the first conductive layer 11 must be neither too large nor too small. When the thickness F is too large (F > 200 μm), the overall thickness of the tab assembly 100 increases. After battery encapsulation, a large gap will form between the tab adhesive 20 and the aluminum-plastic film. This not only increases the risk of battery leakage during drop tests, but also causes the tab assembly 100 to bulge significantly compared to the surrounding electrode plates when connected to the cell body. During compression tests, this bulge causes the area to experience higher local pressure, increasing the risk of current collector tearing and potentially leading to cell failure. When the thickness F of the first conductive layer 11 is too small (F < 1 μm), although a thinner first conductive layer 11 can reduce the current transmission path length, the cross-sectional area of ​​the first conductive layer 11 decreases, leading to increased resistance. This reduces the battery's charging and discharging efficiency and affects the overall battery performance. Therefore, the thickness F of the first conductive layer 11 is set to satisfy the relationship: 1μm≤F≤200μm. This moderate thickness effectively ensures good adhesion between the tab adhesive 20 and the aluminum-plastic film, reducing the formation of voids. This not only helps improve the battery's sealing performance and prevent electrolyte leakage, but also provides additional protection for the battery during drop tests, reducing the risk of battery damage. Simultaneously, it ensures a smoother connection between the tab assembly 100 and the cell body, avoiding tearing of the current collector due to excessive local pressure during compression tests. This helps improve the internal structural stability of the battery and extend its lifespan. Furthermore, the moderate thickness of the first conductive layer 11 reduces the current transmission path length and lowers resistance while ensuring sufficient conductivity. This helps improve the battery's charge and discharge efficiency, increasing its power density and energy density.

[0054] Similarly, the thickness G of the second conductive layer 12 must be neither too large nor too small. When the thickness G of the second conductive layer 12 is too large (G > 200 μm), the overall thickness of the tab assembly 100 increases. After battery encapsulation, a large gap will form between the tab adhesive 20 and the aluminum-plastic film. This not only increases the risk of battery leakage during drop tests, but also causes the tab assembly 100 to bulge significantly compared to the surrounding electrode sheets when connected to the cell body. During compression tests, this bulge leads to higher local pressure in this area, increasing the risk of current collector tearing and potentially causing cell failure. When the thickness G of the second conductive layer 12 is too small (F < 1 μm), although a thinner second conductive layer 12 can reduce the current transmission path length, a smaller thickness G results in a smaller cross-sectional area of ​​the second conductive layer 12, leading to increased resistance. This reduces the battery's charging and discharging efficiency and affects the overall battery performance. Therefore, the thickness G of the second conductive layer 12 is set to satisfy the relationship: 1μm≤F≤200μm. This moderate thickness G effectively ensures good adhesion between the tab adhesive 20 and the aluminum-plastic film, reducing the formation of voids. This not only helps improve the battery's sealing performance and prevent electrolyte leakage, but also provides additional protection for the battery during drop tests, reducing the risk of battery damage. Simultaneously, it ensures a smoother connection between the tab assembly 100 and the cell body, avoiding tearing of the current collector due to excessive local pressure during compression tests. This helps improve the internal structural stability of the battery and extend its lifespan. Furthermore, the moderately thick second conductive layer 12 can reduce the current transmission path length and lower resistance while ensuring sufficient conductivity. This helps improve the battery's charge and discharge efficiency, increasing its power density and energy density.

[0055] Furthermore, the thickness F of the first conductive layer 11 is 1 μm, 5 μm, 10 μm, 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 110 μm, 120 μm, 130 μm, 140 μm, 150 μm, 160 μm, 170 μm, 180 μm, 190 μm, 199 μm, or 200 μm. However, it is not limited to the listed values, and other values ​​within the range are also applicable.

[0056] The thickness G of the second conductive layer 12 is 1 μm, 5 μm, 10 μm, 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 110 μm, 120 μm, 130 μm, 140 μm, 150 μm, 160 μm, 170 μm, 180 μm, 190 μm, 199 μm, or 200 μm. However, it is not limited to the listed values, and other values ​​within the range are also applicable.

[0057] In some embodiments, the thickness F of the first conductive layer 11 and the thickness G of the second conductive layer 12 satisfy the following relationships: F = G; or, F > G; or, F < G. When the thickness F of the first conductive layer 11 and the thickness G of the second conductive layer 12 are equal, i.e., F = G, the manufacturing process is effectively simplified, reducing additional processing steps and quality control requirements caused by thickness differences. Simultaneously, it helps reduce the difference in current transmission paths between the first conductive layer 11 and the second conductive layer 12, improving the battery's charging and discharging efficiency and performance. When the thickness F of the first conductive layer 11 is greater than the thickness G of the second conductive layer 12, i.e., F > G, effectively increasing the thickness F of the first conductive layer 11 can effectively reduce resistance, thereby specifically enhancing the battery's conductivity in a specific direction, reducing energy loss, and increasing the battery's output power. Conversely, when the thickness G of the second conductive layer 12 is greater than the thickness F of the first conductive layer 11, i.e., G > F, effectively increasing the thickness G of the second conductive layer 12 can effectively reduce resistance, thereby specifically enhancing the battery's conductivity in a specific direction, reducing energy loss, and increasing the battery's output power.

[0058] In some embodiments, the thickness J of the polymer layer 13 satisfies the relationship: 1μm≤J≤200μm. The thickness J of the polymer layer 13 cannot be too large or too small. When the thickness J of the polymer layer 13 is too large, i.e., J>200μm, the overall thickness of the tab assembly 100 increases. After battery encapsulation, a large gap will form between the tab adhesive 20 and the aluminum-plastic film. This not only increases the risk of battery leakage during drop tests, but also causes the tab assembly 100 to bulge significantly compared to the surrounding electrode sheets when connected to the cell body. During compression tests, this bulge causes the area to experience higher local pressure, increasing the risk of current collector tearing and potentially leading to cell failure. Furthermore, an excessively thick polymer layer 13 may reduce the overall flexibility of the material, decreasing the folding resistance of the tab assembly 100 and making it prone to breakage during bending. When the thickness J of the polymer layer 13 is too small, i.e., J < 1 μm, the thin polymer layer 13 may be more prone to breakage or deformation during processing, increasing the difficulty and cost of quality control in the production process. Therefore, the thickness J of the polymer layer 13 is set to satisfy the relationship: 1 μm ≤ J ≤ 200 μm. A moderate thickness J of the polymer layer 13 helps to form a tight fit during battery encapsulation, reducing the gap between the tab adhesive 20 and the aluminum-plastic film, thereby reducing the risk of battery leakage, especially in drop tests. In extrusion tests, a polymer layer 13 of appropriate thickness can reduce the protrusion of the tab assembly 100 relative to the surrounding electrodes, thereby reducing the local pressure in that area and reducing the risk of current collector tearing. This is of great significance for improving battery safety performance and extending battery life. Furthermore, within this thickness range, the polymer layer 13 can maintain sufficient flexibility, making the tab assembly 100 less prone to breakage during bending. Simultaneously, it helps to reduce breakage and deformation during processing, thereby reducing the difficulty and cost of quality control in the production process. This contributes to improving battery production efficiency and consistency.

[0059] Furthermore, the thickness J of the polymer layer 13 is 1 μm, 5 μm, 10 μm, 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 110 μm, 120 μm, 130 μm, 140 μm, 150 μm, 160 μm, 170 μm, 180 μm, 190 μm, 199 μm, or 200 μm. However, it is not limited to the listed values, and other values ​​within the range are also applicable.

[0060] The performance of the tab assembly 100 provided by this utility model will be described below through specific embodiments and comparative examples.

[0061] Example 1:

[0062] The tab assembly 100 includes a tab body 10 and tab adhesive 20 disposed on the tab body 10. The tab body 10 includes a first conductive layer 11, a second conductive layer 12, and a polymer layer 13 disposed between the first conductive layer 11 and the second conductive layer 12. The first conductive layer 11 and the second conductive layer 12 are both aluminum layers, and the thickness F of the first conductive layer 11 and the thickness G of the second conductive layer 12 are both 1 μm. The polymer layer 13 is a polyethylene terephthalate layer, and the thickness J of the polymer layer 13 is 6 μm.

[0063] Example 2:

[0064] The difference from Embodiment 1 is that both the first conductive layer 11 and the second conductive layer 12 are nickel layers.

[0065] Example 3:

[0066] The difference from Example 1 is that the thickness F of the first conductive layer 11 and the thickness G of the second conductive layer 12 are 5 μm, and the thickness J of the polymer layer 13 is 10 μm.

[0067] Example 4:

[0068] The difference from Example 3 is that both the first conductive layer 11 and the second conductive layer 12 are nickel layers.

[0069] Comparative Example 1:

[0070] The thickness of a standard aluminum tab is 80μm.

[0071] Comparative Example 2:

[0072] A typical nickel tab has a thickness of 80 μm.

[0073] Cell fabrication and testing methods:

[0074] To evaluate the actual performance of these tab assemblies 100, cells M, N, and L were fabricated.

[0075] The battery cell M includes a positive electrode, a negative electrode, and a separator. The tab assembly 100 of Example 1 is welded onto the current collector of the positive electrode, and the tab assembly 100 of Example 2 is welded onto the current collector of the negative electrode.

[0076] Unlike cell M, in cell N, the tab assembly 100 of embodiment 3 is welded to the current collector of the positive electrode, and the tab assembly 100 of embodiment 4 is welded to the current collector of the negative electrode.

[0077] Unlike cell M, in cell L, aluminum tabs of Comparative Example 1 are welded to the current collector of the positive electrode, and nickel tabs of Comparative Example 2 are welded to the current collector of the negative electrode.

[0078] Drop test method:

[0079] Charge the battery cells to 100% SOC (State of Charge);

[0080] We are preparing to conduct a drop test, dropping the battery cell from a height of 1 meter onto a hard concrete floor.

[0081] The drop test is to be performed with the following specific requirements: drop the battery cell from the positive and negative directions of the X-axis, Y-axis, and Z-axis respectively, for a total of 6 directions (X positive, X negative, Y positive, Y negative, Z positive, Z negative), drop once in each direction, for a total of 6 drop tests.

[0082] Compression test method:

[0083] Charge the battery cells to 100% of their SOC (State of Charge).

[0084] The charged battery cell sample was placed between two parallel test plates.

[0085] A compressive force is applied to the battery cell, and this force should be within the range of 13kN±1kN;

[0086] During the test, the applied pressure must be continuously monitored. When the preset maximum pressure value is reached, or when a sudden drop in pressure to 1 / 3 of the initial value is observed, the pressure application should be stopped immediately and the pressure should be released.

[0087] It should be noted that during the entire test, it is essential to ensure that no external short circuit occurs in the battery cell. This test only applies to the compression test on the wide side of the battery cell.

[0088] Drop tests were conducted on cells M, N, and L. The test results are shown in Table 1.

[0089] Table 1: Comparison of Drop Test Results for Cells M, N, and L

[0090]

[0091]

[0092] Crushing tests were conducted on cells M, N, and L. The test results are shown in Table 2.

[0093] Table 2: Comparison of extrusion tests for cells M, N, and L

[0094]

[0095] As shown in Table 1, cells M and N performed excellently in all tested samples, with no leakage, tab damage, fire, or explosion, and were therefore deemed to have passed the test. In contrast, some samples of cell L showed leakage and abnormal tab shape after the drop test, and were therefore deemed to have failed the test. Abnormal tab shape included tab breakage or tab deformation.

[0096] As shown in Table 2, all test samples of cells M and N successfully passed the test without any fire or explosion. The test results for cell L were more mixed. Some samples, although their voltage decreased, remained stable and no safety incidents occurred; however, the other two samples exploded during the test, and the test was deemed a failure.

[0097] In summary, the thickness of the tab assembly 100 in Embodiments 1-4 of this invention is less than the thickness of the aluminum tab in Comparative Example 1 and the nickel tab in Comparative Example 2. Furthermore, the bending resistance of the tab assembly 100 in Embodiments 1-4 of this invention is superior to that of the aluminum tab in Comparative Example 1 and the nickel tab in Comparative Example 2. Therefore, the battery cell M prepared using the tab assembly 100 of Embodiments 1-2, and the battery cell N prepared using the tab assembly 100 of Embodiments 3-4, have smaller gaps between the tab adhesive 20 and the aluminum-plastic film, making it less likely for battery cells M and N to leak or for the tab assembly 100 to break during drop tests. Therefore, battery cells M and N have extremely high pass rates in drop tests.

[0098] Meanwhile, since the thickness of the first conductive layer 11 and the thickness G of the second conductive layer 12 of the tab assembly 100 in Examples 1 to 4 are both small, especially when the thickness F of the first conductive layer 11 and the thickness G of the second conductive layer 12 are both 1 μm, even if the tab assembly 100 breaks, the burrs formed by the first conductive layer 11 and the second conductive layer 12 are small, thereby effectively avoiding puncturing the separator and causing a short circuit in the battery cell.

[0099] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention.

Claims

1. A tab assembly, characterized by: The tab assembly (100) comprises a tab body (10) and a tab rubber (20) arranged on the tab body (10), the tab body (10) comprises a first conductive layer (11), a second conductive layer (12) and a polymer layer (13), the polymer layer (13) is arranged between the first conductive layer (11) and the second conductive layer (12).

2. The tab assembly of claim 1, wherein: The thickness F of the first conductive layer (11) and the thickness J of the polymer layer (13) satisfy the relationship: F≤J; And / or, the thickness G of the second conductive layer (12) and the thickness J of the polymer layer (13) satisfy the relationship: G≤J.

3. The tab assembly of claim 2, wherein: The thickness F of the first conductive layer (11) satisfies the relationship: 1μm≤F≤200μm; And / or, the thickness G of the second conductive layer (12) satisfies the relationship: 1μm≤G≤200μm.

4. The tab assembly of any one of claims 1 to 3, wherein: The thickness F of the first conductive layer (11) and the thickness G of the second conductive layer (12) satisfy the relationship: F=G; Or, F>G; Or, F<G.

5. The tab assembly of claim 2, wherein: The thickness J of the polymer layer (13) satisfies the relationship: 1μm≤J≤200μm.

6. The tab assembly of claim 1, wherein: The first conductive layer (11) is an aluminum layer, a nickel layer, a copper layer, a copper-aluminum alloy layer, a copper-nickel alloy layer, an aluminum-nickel alloy layer or a copper-aluminum-nickel alloy layer; And / or, the second conductive layer (12) is an aluminum layer, a nickel layer, a copper layer, a copper-aluminum alloy layer, a copper-nickel alloy layer, an aluminum-nickel alloy layer or a copper-aluminum-nickel alloy layer.

7. The tab assembly of claim 6, wherein: The first conductive layer (11) and the second conductive layer (12) are metal layers or alloy layers of the same type.

8. The tab assembly of claim 1, wherein: The polymer layer (13) is a polypropylene layer, a polyethylene terephthalate layer or a polyimide layer.

9. A battery, characterized by: The battery comprises an aluminum plastic film and a battery core, the aluminum plastic film has a receiving cavity, the battery core comprises a battery core body and the tab assembly according to any one of claims 1-8, the tab assembly (100) is arranged at one end of the battery core body, and the tab assembly (100) partially extends out of the aluminum plastic film.

10. An electrical device, characterized by: The battery comprises the battery according to claim 9.

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