battery

Abstract

The application provides a battery. The battery comprises a shell and an electric core. The electric core comprises a first electrode and a second electrode, and an insulation layer is arranged between the first electrode and the second electrode. The first electrode is a negative electrode, and the second electrode is a positive electrode. The first electrode comprises a first current collector extending in a first direction and a first electrode film formed on the outer side of the first current collector. The second electrode comprises a second current collector extending in the first direction and a second electrode film formed on the outer side of the second current collector. The second electrode is arranged around the first electrode. In the first direction, the end of the first current collector is provided with a negative electrode empty foil area, the first electrode further comprises a first lead wire connected with the negative electrode empty foil area, the end of the second current collector is provided with a positive electrode empty foil area, and the second electrode further comprises a second lead wire connected with the positive electrode empty foil area. The area of the positive electrode empty foil area is A1, the area of the negative electrode empty foil area is A2, and A1 / A2<1.

Description

Technical Field

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

[0002] Lithium-ion batteries (such as lithium-ion pouch batteries) are rechargeable high-energy batteries that operate by moving lithium ions between the positive and negative electrodes to perform the charging and discharging process. Due to their advantages such as high energy density, high battery voltage, wide operating temperature range, and long storage life, lithium-ion batteries are widely used in mobile phones, laptops, and wearable electronic devices.

[0003] In recent years, with the upgrading of small smart wearable products, components of wearable products (such as watch straps and temples of smartwatches and bracelets, glasses, etc.) also need to be fitted with lithium batteries that can fit their internal space. This places higher demands on the battery's installability, flexibility, and bendability. The traditional designs of square pouch batteries and square steel-cased batteries are no longer suitable for use in the components of the aforementioned smart wearable products.

[0004] Therefore, it is essential to develop a new type of battery with a flexible structure. Summary of the Invention

[0005] In view of this, embodiments of this application provide a bendable battery to meet the requirements of battery flexibility and bendability.

[0006] An embodiment of this application provides a battery comprising a casing and a cell. The casing has a receiving cavity, and the cell is disposed within the receiving cavity. The cell includes a first electrode and a second electrode, at least one of which is linear. An insulating layer is disposed between the first electrode and the second electrode. The first electrode is a negative electrode, and the second electrode is a positive electrode. The first electrode includes a first current collector extending along a first direction and a first electrode diaphragm formed on the outer side of the first current collector. The second electrode includes a second current collector extending along the first direction and a second electrode diaphragm formed on the outer side of the second current collector. The second electrode is wound around the first electrode. Along the first direction, a negative electrode empty foil region is provided at the end of the first current collector. The first electrode also includes a first lead connected to the negative electrode empty foil region. A positive electrode empty foil region is provided at the end of the second current collector. The second electrode also includes a second lead connected to the positive electrode empty foil region. The area of ​​the positive electrode empty foil region is A1, and the area of ​​the negative electrode empty foil region is A2, where A1 / A2 < 1.

[0007] Optionally, in some embodiments, along the first direction, the length of the positive electrode empty foil region is L1, where L1 satisfies: 2 mm ≤ L1 ≤ 10 mm; and / or, the length of the negative electrode empty foil region is L2, where L2 satisfies: 2 mm ≤ L2 ≤ 10 mm; and / or, L1 and L2 satisfy: L1 ≤ L2.

[0008] Optionally, in some embodiments, the length of the battery is L3, which is 5 cm to 50 cm, and L1 and L3 satisfy: 0.004≤L1 / L3≤0.2, and / or L2 and L3 satisfy: 0.004≤L2 / L3≤0.2.

[0009] Optionally, in some embodiments, along the second direction, there is a spacing D between the positive electrode empty foil region and the negative electrode empty foil region, where D satisfies: D > 0.1 mm, and the second direction is perpendicular to the first direction.

[0010] Optionally, in some embodiments, the first lead is riveted, hinged, welded, or bonded to the negative electrode empty foil area; and / or, the second lead is riveted, hinged, welded, or bonded to the positive electrode empty foil area.

[0011] Optionally, in some embodiments, the connection portion of the first lead to the negative electrode empty foil region forms a first connection region, and a first insulating member is disposed on the first connection region. The connection portion of the second lead to the positive electrode empty foil region forms a second connection region, and a second insulating member is disposed on the second connection region. The first insulating member extends to cover the end of the first electrode diaphragm for a first length L4, where L4 is 0.2 mm to 1 mm; and / or, the second insulating member extends to cover the end of the second electrode diaphragm for a second length L5, where L5 is 0.2 mm to 1 mm.

[0012] Optionally, in some embodiments, the first lead includes a first portion extending out of the housing along a first direction, the first portion being located on the side of the first connection region away from the first electrode diaphragm, and a third insulating member is formed on the first portion, at least a portion of the third insulating member being bonded to the housing. The second lead includes a second portion extending out of the housing along a first direction, the second portion being located on the side of the second connection region away from the second electrode diaphragm, and a fourth insulating member is formed on the second portion, at least a portion of the fourth insulating member being bonded to the housing. Along the first direction, the length by which the first insulating member covers the third insulating member is a third length L6, where L6 is 0.2 mm to 1 mm; and / or, the length by which the second insulating member covers the fourth insulating member is a fourth length L7, where L7 is 0.2 mm to 1 mm.

[0013] Optionally, in some embodiments, the first electrode is linear, the diameter or / thickness of the first lead is d1, the diameter of the first current collector is d2, d1 and d2 satisfy: 1≤d1 / d2≤5, and / or, the diameter d5 of the first electrode is 50 μm~500 μm; and / or, the second electrode is linear, the diameter or thickness of the second lead is d3, the diameter of the second current collector is d4, d3 and d4 satisfy: 1≤d3 / d4≤5, and / or, the diameter d6 of the second electrode is 50 μm~500 μm; and / or The tensile strength of the first electrode and / or the second electrode is ≥50 MPa, and / or the elongation at break of the first electrode and / or the second electrode is ≥1%.

[0014] Optionally, in some embodiments, the housing has a first surface and a second surface, the first surface facing the battery cell and the second surface away from the battery cell. At least partially, a polymer layer is disposed on each of the first and second surfaces. Along a first direction, the polymer layers are bonded and sealed to form the housing. A first lead and a second lead extend from the housing. The polymer layer includes one or more of polyethylene, polypropylene, a copolymer of polypropylene and acrylic acid, a copolymer of polyethylene and acrylic acid, polyvinyl chloride, a terpolymer of polypropylene-butene-ethylene, and a copolymer of ethylene and propylene.

[0015] Optionally, in some embodiments, the first electrode is linear, the diameter or / thickness of the first lead is d1, the diameter of the first current collector is d2, d1 and d2 satisfy: 1≤d1 / d2≤5, and / or, the diameter d5 of the first electrode is 50 μm~500 μm; and / or, the second electrode is sheet-like, the diameter or thickness of the second lead is d3, the thickness of the second current collector is D4, d3 and D4 satisfy: 1≤d3 / D4≤5, and / or, the thickness D6 of the second electrode is 50 μm~500 μm; and / or The tensile strength of the first electrode and / or the second electrode is ≥50 MPa, and / or the elongation at break of the first electrode and / or the second electrode is ≥1%.

[0016] In this application, at least one of the first electrode and the second electrode is linear, and an insulating layer is disposed between the first electrode and the second electrode to isolate them. The second electrode is wound around the first electrode, with the first electrode being the negative electrode and the second electrode being the positive electrode. This arrangement allows for relative deformation between the two electrodes, thereby improving the battery's flexibility and giving it a certain degree of bendability. Therefore, it overcomes the problem in existing lithium-ion batteries where the positive and negative electrodes and the separator are typically formed by multiple stacks or layers, resulting in poor battery flexibility and deformability, and an inability to bend to fit the installation space.

[0017] However, when the electrode sheet is a wire electrode, the welding difficulty and welding instability increase due to structural differences. Furthermore, compared to sheet electrodes, the elongated structure of wire electrodes forces electrons to travel a long axial distance, resulting in a narrower electron transport path and more obstructed ion transport. Therefore, the resistance increases significantly for the same length, making local concentration polarization more likely at the same charge / discharge rate. When the electrode is a negative electrode, the volume change effect during charge / discharge, coupled with the slower lithium-ion insertion / extraction kinetics and higher charge transfer impedance compared to the positive electrode, leads to greater polarization. When the negative electrode is a wire electrode, localized current density concentration and overheating are more likely, further exacerbating the aforementioned polarization problems and potentially inducing lithium plating.

[0018] Therefore, while improving the flexibility and bendability of the battery, it is necessary to control the size of the empty foil area on the negative and positive electrodes. This application controls the area A1 of the positive electrode empty foil area and the area A2 of the negative electrode empty foil area, ensuring that A1 / A2 < 1, to improve the problem of large negative electrode polarization during charging and discharging. Setting the area of ​​the negative electrode empty foil area larger than that of the positive electrode empty foil area can increase the effective conductive cross-sectional area of ​​the negative electrode current collector, disperse excessively high local current density, and alleviate the electric field concentration effect. Simultaneously, it provides a larger heat dissipation area to improve the aforementioned negative electrode polarization problem, ensuring the overcurrent capacity and internal resistance consistency of the positive and negative electrodes, preventing large differences in internal resistance between the positive and negative electrodes during charging, which could lead to ineffective battery performance and reduced battery cycle performance.

[0019] When A1 / A2 is greater than 1, the above-mentioned polarization problem cannot be improved, resulting in local current density concentration and local overheating of the electrode, reducing the local strength and thermal fatigue resistance of the electrode, and causing the risk of electrode breakage during cycling after the battery is bent. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the drawings only show some embodiments of this application and should not be considered as a limitation of the scope. It should also be understood that the same or similar reference numerals are used in the drawings to represent the same or similar elements. Furthermore, it should be understood that the drawings are merely schematic, and the dimensions and scale of the elements in the drawings are not necessarily precise.

[0021] Figure 1 This is a schematic diagram of the structure of a battery cell according to an embodiment of this application.

[0022] Figure 2 This is another structural schematic diagram of a battery cell according to one embodiment of this application.

[0023] Figure 3 for Figure 2 A magnified view of a portion of point A in the middle.

[0024] Figure 4 This is another structural schematic diagram of a battery cell according to one embodiment of this application.

[0025] Figure 5 This is another structural schematic diagram of a battery cell according to one embodiment of this application.

[0026] Figure 6 This is yet another structural schematic diagram of a battery cell according to an embodiment of this application.

[0027] Figure 7 This is a schematic diagram of the structure of the first electrode according to an embodiment of this application.

[0028] Figure 8 This is a schematic diagram of the structure of the second electrode according to an embodiment of this application.

[0029] Figure 9 This is a schematic diagram of the structure of a battery according to an embodiment of this application.

[0030] Figure 10 This is a cross-sectional structural schematic diagram of the housing according to an embodiment of this application.

[0031] Figure 11 This is another structural schematic diagram of a battery according to one embodiment of this application.

[0032] Figure label: 100. Battery; 10. Cell; 11. First electrode; 111. First current collector; 1111. Negative electrode empty foil area; 112. First electrode diaphragm; 113. First lead; 1131. First part; 114. First connection area; 12. Separator; 13. Second electrode; 131. Second current collector; 1311. Positive electrode empty foil area; 132. Second electrode diaphragm; 133. Second lead; 1331. Second part; 134. Second connection area; 14. First insulating component; 15. Second insulating component; 16. Third insulating component; 17. Fourth insulating component; 20. Housing; 21. First surface; 22. Second surface; 30. Sealing component. Detailed Implementation

[0033] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0034] In recent years, with the upgrading of smart wearable products, there has been a greater demand for the flexibility and bendability of batteries. However, most commercially available lithium-ion batteries are cylindrical, steel-cased, or square pouch cells, and their internal battery cells are usually stacked or wound. These batteries cannot be flexible and bendable, which has played a limiting role in the development of various types of portable devices.

[0035] The following is for reference. Figures 1 to 11 The present application provides an example description of the battery provided in the embodiments.

[0036] refer to Figures 1 to 11 This application provides a battery 100, which includes a casing 20 and a battery cell 10. The casing 20 has a receiving cavity, and the battery cell 10 is disposed within the receiving cavity. The battery cell 10 includes a first electrode 11 and a second electrode 13, at least one of the first electrode 11 and the second electrode 13 being linear. An insulating layer is disposed between the first electrode 11 and the second electrode 13, the first electrode 11 being the negative electrode and the second electrode 13 being the positive electrode. The first electrode 11 includes a first current collector 111 extending along a first direction and a first electrode diaphragm 112 formed on the outer side of the first current collector 111. The second electrode 13 includes a second current collector 131 extending along the first direction and a second electrode diaphragm 132 formed on the outer side of the second current collector 131. The second electrode 13 is wound around the first electrode 11. Along the first direction, the end of the first current collector 111 is provided with a negative electrode empty foil region 1111. The first electrode 11 also includes a first lead 113, which is connected to the negative electrode empty foil region. The end of the second current collector 131 is provided with a positive electrode empty foil region 1311. The second electrode 13 also includes a second lead 133, which is connected to the positive electrode empty foil region 1311. The area of ​​the positive electrode empty foil region 1311 is A1, and the area of ​​the negative electrode empty foil region 1111 is A2. A1 and A2 satisfy: A1 / A2 < 1.

[0037] At least one of the first electrode 11 and the second electrode 13 in this application is linear. An insulating layer is provided between the first electrode 11 and the second electrode 13 to isolate them. The second electrode 13 is wound around the first electrode 11. The first electrode 11 is the negative electrode, and the second electrode 13 is the positive electrode. This arrangement allows for relative deformation between the two electrodes, thereby improving the flexibility of the battery 100 and giving it a certain degree of bendability. Therefore, it overcomes the problem that in existing lithium-ion batteries 100, the positive and negative electrodes and the separator 12 are usually stacked or layered and wound multiple times, resulting in poor flexibility and deformability of the battery 100, making it impossible to bend to fit the installation space.

[0038] However, when the electrode sheet is a wire electrode, the welding difficulty and welding instability increase due to structural differences. Furthermore, compared to sheet electrodes, the elongated structure of wire electrodes forces electrons to travel a long axial distance, resulting in a narrower electron transport path and more obstructed ion transport. Therefore, the resistance increases significantly for the same length, making local concentration polarization more likely at the same charge / discharge rate. When the electrode is a negative electrode, the volume change effect during charge / discharge, coupled with the slower lithium-ion insertion / extraction kinetics and higher charge transfer impedance compared to the positive electrode, leads to greater polarization. When the negative electrode is a wire electrode, localized current density concentration and overheating are more likely, further exacerbating the aforementioned polarization problems and potentially inducing lithium plating.

[0039] Therefore, while improving the flexibility and bendability of the battery 100, it is necessary to control the size of the empty foil area on the negative and positive electrodes of the battery 100. This application controls the area A1 of the positive electrode empty foil area 1311 and the area A2 of the negative electrode empty foil area 1111, ensuring that A1 / A2 < 1. This improves the problem of large negative electrode polarization during charging and discharging. Setting the area of ​​the negative electrode empty foil area 1111 to be larger than that of the positive electrode empty foil area 1311 increases the effective conductive cross-sectional area of ​​the negative electrode current collector, disperses excessively high local current density, and alleviates the electric field concentration effect. Simultaneously, it provides a larger heat dissipation area to improve the aforementioned negative electrode polarization problem, ensuring the overcurrent capacity and internal resistance consistency of the positive and negative electrodes, preventing large differences in internal resistance between the positive and negative electrodes during charging, which could lead to ineffective performance of the battery 100 and reduced cycle performance.

[0040] When A1 / A2 is greater than 1, the above-mentioned polarization problem cannot be improved, resulting in local current density concentration and local overheating of the electrode, reducing the local strength and thermal fatigue resistance of the electrode, and causing the risk of electrode breakage during cycling after the battery is bent 100 times.

[0041] In this application, for linear electrodes, the area of ​​the empty foil region (e.g., positive electrode empty foil region 1311 or negative electrode empty foil region 1111) refers to the surface area of ​​the current collector of the empty foil region, which is obtained by measuring the diameter and length of the empty foil region and using the formula for calculating the circumferential area. For sheet-like electrodes, the area of ​​the empty foil region (e.g., positive electrode empty foil region 1311 or negative electrode empty foil region 1111) refers to the area of ​​the current collector of the empty foil region projected along the thickness direction of the current collector, which is calculated by measuring the length and width of the projected projection.

[0042] In some examples, the material of the first current collector includes stainless steel, aluminum, nickel, titanium, copper, aluminum-cadmium alloy, stainless steel surface-treated with a conductive material, conductive polymer, non-conductive polymer surface-treated with a conductive material, or conductive polymer; further, the conductive material includes one or more of polyacetylene, polyaniline, polypyrrole, polythiophene, polysulfide, indium tin oxide (ITO), silver, nickel, titanium, carbon black, graphite, graphene, carbon fiber, and carbon nanotubes; and / or, the non-conductive polymer includes at least one of polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), polyethylene (PE), polypropylene (PP), polyimide (PI), polyethylene terephthalate (PET), polyvinyl chloride (PVC), and polysiloxane; the conductive polymer includes one or more of polyacetylene, polyaniline, polypyrrole, polythiophene, and polysulfide.

[0043] In some examples, the first electrode diaphragm 112 includes a first material, which includes one or more of natural graphite, artificial graphite or carbonaceous materials, silicon-carbon materials and silicon-oxygen materials, and includes at least one of elemental, alloy or oxide of Si, Sn, Li, Zn, Mg, Cd, Ce and Ni.

[0044] In some examples, the second electrode film 132 includes a second material, such as LiCoO2, LiNiO2, LiMn2O4, LiCoPO4, LiFePO4, LiNiMnCoO2, or LiNiO2. 1-x-y-z Co x M1 y M2 z One or more of O2. M1 and M2 are each independently selected from Al, Ni, Co, Fe, Mn, V, Cr, Ti, W, Ta, Mg and Mo, and x, y and z are each independently the atomic fractions of the elements forming the oxide, 0≤x<0.5, 0≤y<0.5, 0≤z<0.5, and x+y+z≤1.

[0045] In some examples, the material of the second current collector 131 includes stainless steel, aluminum, nickel, titanium, baked carbon, copper, stainless steel surface-treated with carbon, nickel, titanium, or silver, aluminum-cadmium alloys, and non-conductive polymers surface-treated with conductive materials. Exemplarily, the conductive material includes a metal paste of metal powders of Ni, Al, Au, Ag, Al, Pd / Ag, Cr, Ta, Cu, Ba, or ITO, or a carbon paste containing carbon powders of graphite, carbon black, or carbon nanotubes. Exemplarily, the non-conductive polymer includes one or more of polyacetylene, polyaniline, polypyrrole, polythiophene, and polysulfide.

[0046] In one example, the first electrode 11 and the second electrode 13 are both wires, which are intertwined to form a battery cell 10.

[0047] In one example, the first electrode 11 is sheet-shaped and the second electrode 13 is wire-shaped. The first electrode 11 is spirally wound around the second electrode 13, or the first electrode 11 is wrapped around the second electrode 13 (that is, the first electrode 11 is wrapped around the second electrode 13).

[0048] In one example, the second electrode 13 is sheet-shaped and the first electrode 11 is wire-shaped. The second electrode 13 is spirally wound around the first electrode 11, or the second electrode 13 is wrapped around the first electrode 11 (that is, the second electrode 13 is wrapped around the first electrode 11).

[0049] It should be noted that the line shape in this application refers to the length direction being much larger than the dimensions in other directions, that is, it is long and narrow.

[0050] In some embodiments, the length of the positive electrode empty foil region 1311 along the first direction is L1, where L1 satisfies: 2 mm ≤ L1 ≤ 10 mm, for example, 2 mm, 4 mm, 6 mm, 8 mm, or 10 mm. This avoids L1 being too small, which would prevent effective connection with the second lead 133, reducing overcurrent capacity, leading to excessive local heat in the battery 100 and increased internal resistance, affecting the cycle performance and electrical output of the battery 100; or L1 being too large, affecting the energy density of the battery 100.

[0051] In some embodiments, the length of the negative electrode empty foil region 1111 along the first direction is L2, where L2 satisfies: 2 mm ≤ L2 ≤ 10 mm, for example, 2 mm, 4 mm, 6 mm, 8 mm, or 10 mm. This avoids L2 being too small, which would prevent effective connection with the first lead 113, reducing overcurrent capacity, causing excessive local heat in the battery 100, and increasing internal resistance, thus affecting the cycle performance and electrical output of the battery 100. Simultaneously, it improves the length of the negative electrode empty foil region 1111 to address the problem of large negative electrode polarization. Alternatively, if L2 is too large, it would affect the energy density of the battery 100 or cause a capacity mismatch between the positive and negative electrodes, leading to lithium plating problems.

[0052] In some embodiments, L1 and L2 satisfy: L1≤L2, so that the length of the positive electrode empty foil region 1311 is not greater than the length of the negative electrode empty foil region 1111, which is beneficial to improve the negative electrode charging polarization problem. It can ensure the consistency of internal resistance and prevent the negative electrode polarization from being aggravated due to the large difference in internal resistance between the first lead 113 and the second lead 133, thereby reducing the cycle performance of the battery 100.

[0053] In some embodiments, the length of the battery 100 is L3, which is 5 cm to 50 cm, for example, 5 cm, 7 cm, 9 cm, 11 cm, 13 cm, 15 cm, 17 cm, 20 cm, 25 cm, 30 cm, 35 cm, 40 cm, 45 cm, or 50 cm, or any value between them. When the length L3 of the battery 100 meets the above range, the battery 100 is less likely to rebound when bent, and at the same time, it ensures that the internal stress is not too large, reducing the risk of electrode breakage after the battery 100 is bent.

[0054] In some embodiments, L1 and L3 satisfy: 0.004 ≤ L1 / L3 ≤ 0.2, for example, 0.004, 0.005, 0.008, 0.01, 0.03, 0.05, 0.08, 0.1, 0.15, or 0.2, or any value between them. This avoids the positive electrode empty foil region 1311 being too long, occupying too much of the battery 100 length space, leading to energy density loss, or the positive electrode empty foil region 1311 being too short, affecting the strength and stability of the connection with the second lead 133, increasing the internal resistance of the battery 100, and deteriorating the cycle performance of the battery 100.

[0055] In some embodiments, L2 and L3 satisfy: 0.004 ≤ L2 / L3 ≤ 0.2, for example, 0.004, 0.005, 0.008, 0.01, 0.03, 0.05, 0.08, 0.1, 0.15, or 0.2, or any value between them. This avoids the negative electrode empty foil region 1111 being too long, occupying too much of the battery 100 length space, leading to energy density loss, or the negative electrode empty foil region 1111 being too short, affecting the strength and stability of the connection with the first lead 113, increasing the internal resistance of the battery 100, and deteriorating the cycle performance of the battery 100.

[0056] In some embodiments, along the second direction, there is a spacing D between the positive electrode empty foil region 1311 and the negative electrode empty foil region 1111, where D satisfies: D > 0.1 mm, for example, 0.12 mm, 0.13 mm, 0.15 mm, 0.18 mm, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm, or 0.5 mm, etc. The second direction is perpendicular to the first direction.

[0057] This prevents the distance between the first lead 113 and the second lead 133 from being too close, which could cause the positive electrode empty foil region 1311 and the negative electrode empty foil region 1111 to easily overlap and cause a short circuit.

[0058] refer to Figures 2 to 5In some embodiments, the first lead 113 is riveted, hinged, welded, or bonded to the negative electrode empty foil area 1111 to set the first lead 113 in various ways. Here, the connection methods such as hinge and riveting realize the connection between the first lead 113 (tab) and the first current collector 111 through mechanical connection, which can reduce the connection difficulty between the first lead 113 and the negative electrode empty foil area 1111. In addition, multiple first leads 113 can be connected at the same time to ensure the current carrying capacity of the first lead 113.

[0059] In some embodiments, the second lead 133 is riveted, hinged, welded, or bonded to the positive electrode empty foil region 1311. Here, the connection methods such as hinge and riveting achieve the connection between the second lead 133 (tab) and the second current collector 131 through mechanical connection, which can reduce the connection difficulty between the second lead 133 and the positive electrode empty foil region 1311. In addition, multiple second leads 133 can be connected at the same time to ensure the current carrying capacity of the second lead 133.

[0060] Next, refer to Figures 2 to 5 In some embodiments, the connection portion of the first lead 113 and the negative electrode empty foil area 1111 forms a first connection area 114, and a first insulating element 14 is provided on the first connection area 114. The connection portion of the second lead 133 and the positive electrode empty foil area 1311 forms a second connection area 134, and a second insulating element 15 is provided on the second connection area 134 to prevent burrs in the connection area from piercing the housing 20, and at the same time to play the role of insulation and isolation.

[0061] refer to Figure 4 In one example, the first insulating element 14 (e.g., insulating tape) extends to cover the end of the first electrode diaphragm 112 by a first length L4, where L4 is 0.2 mm to 1 mm, for example, 0.2 mm, 0.4 mm, 0.6 mm, 0.8 mm, or 1 mm. This ensures that the connection area (e.g., solder area) and the end edge of the electrode diaphragm are covered by insulating tape, improving the safety of the battery 100, while avoiding excessive ineffective area occupied by the first insulating element 14 and thus preventing energy density waste.

[0062] Next, refer to Figure 4 In one example, the second insulating element 15 (e.g., insulating tape) extends to cover the end of the second electrode diaphragm 132 by a second length L5, where L5 is 0.2 mm to 1 mm, for example, 0.2 mm, 0.4 mm, 0.6 mm, 0.8 mm, or 1 mm. This ensures that the connection area (e.g., solder area) and the end edge of the electrode diaphragm are covered with insulating tape, improving the safety of the battery 100, while avoiding excessive ineffective area occupied by the second insulating element 15 and preventing wasted energy density.

[0063] refer to Figure 9In some embodiments, the first lead 113 includes a first portion 1131 extending out of the housing 20. Along a first direction, the first portion 1131 is located on the side of the first connection region 114 away from the first electrode diaphragm 112. A third insulating element 16 (e.g., adhesive for the first lead 113) is formed on the first portion 1131, and at least a portion of the third insulating element 16 is bonded to the housing 20. The second lead 133 includes a second portion 1331 extending out of the housing 20. Along a first direction, the second portion 1331 is located on the side of the second connection region 134 away from the second electrode diaphragm 132. A fourth insulating element 17 (e.g., adhesive for the second lead 133) is formed on the second portion 1331, and at least a portion of the fourth insulating element 17 is bonded to the housing 20. Providing insulating elements at the connection points of the first lead 113 and the second lead 133 with the housing 20 ensures the sealing effect of the battery 100, prevents moisture from entering the battery 100, and improves the safety performance of the battery 100.

[0064] Return to reference Figure 4 In one example, along the first direction, the first insulating member 14 covers the third insulating member 16 by a third length L6, where L6 is 0.2 mm to 1 mm, for example, 0.2 mm, 0.4 mm, 0.6 mm, 0.8 mm, or 1 mm. This ensures, on the one hand, that the gap between the end edge of the first electrode diaphragm 112 and the negative electrode empty foil region 1111 is completely covered, preventing the first electrode diaphragm 112 from detaching from its edge and avoiding partial exposure of the negative electrode empty foil region 1111, which could increase safety hazards. On the other hand, it allows for a smooth transition in thickness between the end edge of the first electrode diaphragm 112 and the negative electrode empty foil region 1111, while minimizing liquid penetration and corrosion of the connection area between the first lead 113 and the negative electrode empty foil region 1111.

[0065] Next, refer to Figure 4 In one example, the second insulating member 15 covers the fourth insulating member 17 by a length L7, which is 0.2 mm to 1 mm, for example, 0.2 mm, 0.4 mm, 0.6 mm, 0.8 mm, or 1 mm. This ensures, on the one hand, that the gap between the end edge of the second electrode diaphragm 132 and the positive electrode empty foil region 1311 is completely covered, preventing the edge of the second electrode diaphragm 132 from detaching and avoiding increased safety hazards due to partial exposure of the positive electrode empty foil region 1311. On the other hand, it allows for a smooth transition in thickness between the end edge of the second electrode diaphragm 132 and the positive electrode empty foil region 1311, while minimizing liquid penetration and corrosion of the connection area between the second lead 133 and the positive electrode empty foil region 1311.

[0066] refer to Figure 7In some embodiments, the first electrode 11 is linear, the diameter of the first lead 113 (if the first lead 113 is linear) or / or the thickness of the first lead 113 (if the first lead 113 is sheet-like) is d1, and the diameter of the first current collector 111 is d2. d1 and d2 satisfy: 1 ​​≤ d1 / d2 ≤ 5, for example, 1, 1.5, 2, 3, 4, or 5, to ensure that the dimensions of the first lead 113 and the first current collector 111 are compatible, ensuring that both have certain mechanical properties while reducing the difficulty of connecting them. Furthermore, it can also satisfy the current transmission capacity while avoiding the first lead 113 being too large, which would affect the subsequent insertion of the battery cell 10 into the casing and the sealing safety of the battery 100.

[0067] Next, refer to Figure 7 In some embodiments, the diameter d5 of the first electrode 11 is 50 μm to 500 μm, for example, 50 μm, 70 μm, 100 μm, 130 μm, 150 μm, 170 μm, 200 μm, 250 μm, 300 μm, 350 μm, 400 μm, 450 μm or 500 μm, to ensure flexibility while ensuring that it has suitable internal resistance and overcurrent capability, thereby improving the electrical performance of the battery 100.

[0068] refer to Figure 8 In some embodiments, the second electrode 13 is linear, the diameter or thickness of the second lead 133 is d3, and the diameter of the second current collector 131 is d4. d3 and d4 satisfy: 1 ​​≤ d3 / d4 ≤ 5, for example, 1, 1.5, 2, 3, 4, or 5, to ensure that the dimensions of the second lead 133 and the second current collector 131 are compatible, ensuring that both have certain mechanical properties while reducing the difficulty of their connection. Furthermore, it can also satisfy the current transmission capacity while avoiding the second lead 133 being too large, which would affect the subsequent insertion of the battery cell 10 into the casing and the sealing safety of the battery 100.

[0069] Next, refer to Figure 8 In some embodiments, the diameter d6 of the second electrode 13 is 50 μm to 500 μm, for example, 50 μm, 70 μm, 100 μm, 130 μm, 150 μm, 170 μm, 200 μm, 250 μm, 300 μm, 350 μm, 400 μm, 450 μm or 500 μm, to ensure flexibility while ensuring that it has suitable internal resistance and overcurrent capability, thereby improving the electrical performance of the battery 100.

[0070] In some embodiments, the tensile strength of the first electrode 11 and / or the second electrode 13 is ≥50 MPa, for example, 50 MPa, 52 MPa, 55 MPa, 60 MPa, 65 MPa, 70 MPa, 75 MPa, or 80 MPa, to ensure sufficient strength and the ability to undergo moderate deformation without breaking during bending deformation. In some embodiments, the elongation at break of the first electrode 11 and / or the second electrode 13 is ≥1%, for example, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, or 10%, to ensure deformability.

[0071] In some embodiments, the first electrode 11 is linear, the diameter and / or thickness of the first lead 113 is d1, and the diameter of the first current collector 111 is d2. d1 and d2 satisfy: 1 ​​≤ d1 / d2 ≤ 5, for example, 1, 1.5, 2, 3, 4, or 5, to ensure that the dimensions of the first lead 113 and the first current collector 111 are compatible, ensuring that both have certain mechanical properties while reducing the difficulty of their connection. Furthermore, it can also meet the current transmission capacity requirements. At the same time, it avoids the first lead 113 being too large, which would affect the subsequent insertion of the battery cell 10 into the casing and the sealing safety of the battery 100. The diameter d5 of the first electrode 11 is 50 μm to 500 μm, for example, 50 μm, 70 μm, 100 μm, 130 μm, 150 μm, 170 μm, 200 μm, 250 μm, 300 μm, 350 μm, 400 μm, 450 μm, or 500 μm, to ensure flexibility while maintaining suitable internal resistance and overcurrent capability, thereby improving the electrical performance of the battery 100. The second electrode 13 is sheet-shaped, with the diameter or thickness of the second lead 133 being d3, and the thickness of the second current collector 131 being D4. d3 and D4 satisfy: 1 ​​≤ d3 / D4 ≤ 5, for example, 1, 1.5, 2, 3, 4, or 5, to ensure that the dimensions of the second lead 133 and the second current collector 131 are compatible, guaranteeing certain mechanical properties while reducing the difficulty of their connection. Furthermore, it also satisfies the current transmission capability. Meanwhile, to avoid the second lead 133 being too large, which would affect the subsequent insertion of the battery cell 10 into the casing and the sealing safety of the battery 100, the thickness D6 of the second electrode 13 is 50 μm to 500 μm, for example, 50 μm, 70 μm, 100 μm, 130 μm, 150 μm, 170 μm, 200 μm, 250 μm, 300 μm, 350 μm, 400 μm, 450 μm or 500 μm, to ensure flexibility while ensuring it has suitable internal resistance and overcurrent capacity, thereby improving the electrical performance of the battery 100.

[0072] refer to Figure 10In some embodiments, the housing 20 has a first surface 21 and a second surface 22, the first surface 21 facing the battery cell 10 and the second surface 22 away from the battery cell 10. At least partially, a polymer layer is disposed on each of the first surface 21 and the second surface 22. The polymer layers are bonded and sealed along a first direction to form the housing 20 (i.e., the housing 20 surrounds the battery cell 10 and is sealed along the first direction) to ensure reliable sealing. A first lead 113 and a second lead 133 extend from the housing 20. The polymer layer includes one or more of polyethylene, polypropylene, a copolymer of polypropylene and acrylic acid, a copolymer of polyethylene and acrylic acid, polyvinyl chloride, a terpolymer of polypropylene-butene-ethylene, and a copolymer of ethylene and propylene.

[0073] refer to Figure 11 In some embodiments, the housing 20 is provided with sealing members 30 at both ends along the first direction, and the first lead 113 and the second lead 133 are led out from the housing 20 at the sealing member 30.

[0074] In some embodiments, the housing 20 is a heat shrink tubing, and the two ends of the housing 20 are heat-sealed along the first direction X. The first lead 113 and the second lead 133 are led out from the end of the housing 20.

[0075] Secondly, embodiments of this application provide an electrical device that includes the battery 100 described above.

[0076] For example, the electrical device can be a watch strap, a wristband, or an eyeglass armband, etc.

[0077] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications or equivalent substitutions made within the spirit and principles of this application should be included within the protection scope of this application.

[0078] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, 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, and therefore should not be construed as a limitation of this application.

[0079] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0080] In this application, unless otherwise expressly 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 part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between components; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0081] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0082] In this application, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is 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. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0083] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

[0084] The present application is described in detail below with reference to specific embodiments, which are used to understand rather than limit the present application.

[0085] Unless otherwise specified, all materials and reagents used in the following examples are commercially available. Unless otherwise specified, the processing procedures and techniques involved are conventional technical methods.

[0086] Example 1 Negative electrode preparation: The negative electrode active material (i.e., negative electrode active material: graphite and silicon carbide), sodium carboxymethyl cellulose, styrene-butadiene rubber, and conductive carbon black are dispersed in deionized water (or water) at a mass percentage of 94:1.5:1.5:3 and mixed evenly to obtain a slurry. The prepared negative electrode slurry is uniformly coated onto the negative electrode current collector, dried at 100°C, compacted, and slit to obtain the negative electrode. The negative electrode active material is a graphite and silicon carbide composite material. The silicon content in the negative electrode active material is 19%, and the silicon content in the silicon carbide composite material is 45%. The silicon content is controlled by controlling the content of the silicon carbide composite material in the negative electrode active material. The negative electrode current collector consists of a core material formed of high molecular weight polyethylene fiber and copper wires wound around the core material, with winding gaps between the copper wires.

[0087] Positive electrode preparation: The positive electrode active material lithium nickel cobalt manganese oxide (NCM), binder polyvinylidene fluoride, and conductive agent carbon black are mixed in a mass percentage ratio of 97.2:1.8:1. An appropriate amount of N-methylpyrrolidone is added as a solvent, and the mixture is stirred until homogeneous, forming a uniformly dispersed electrode slurry with a solid content of 65 wt%. The prepared positive electrode slurry is uniformly coated onto the positive electrode current collector, dried at 100℃, compacted, and slit to form the positive electrode. The positive electrode current collector is aluminum foil.

[0088] Both sides of the positive current collector are coated with positive electrode slurry.

[0089] Then, while bringing the prepared negative and positive electrodes into contact with each other, the positive electrode is spirally wound onto the rod-shaped negative electrode in a first direction, with winding gaps between adjacent positive electrode segments, and an insulating layer (i.e., separator 12) is provided between the positive and negative electrodes to form a cell 10. The obtained cell 10 is then surrounded by a casing 20 made of polyvinyl chloride (PVC) resin coated with metallic nickel to obtain a battery 100.

[0090] Then, the battery cell 10 is housed in the casing 20 and manufactured into a battery 100 through steps such as encapsulation, electrolyte injection, formation, secondary sealing, and capacity testing. Here, the electrolyte is a commercially available electrolyte.

[0091] The area of ​​the positive electrode empty foil region 1311 is A1, and the area of ​​the negative electrode empty foil region 1111 is A2, with A1 / A2 = 0.7. The length of the positive electrode empty foil region 1311 is L1 = 3 mm, and the length of the negative electrode empty foil region 1111 is L2 = 8 mm. The length of the battery 100 is L3 = 35 cm. L1 / L3 = 0.009, L2 / L3 = 0.023. The distance between the positive electrode empty foil region 1311 and the negative electrode empty foil region 1111 is D = 0.5 mm. The first lead 113 is welded to the negative electrode empty foil region 1111, and the second lead 133 is welded to the positive electrode empty foil region 1311. Insulating tape is provided at the weld points. The first insulating component 14 covers the end of the first electrode diaphragm 112 by L4 = 0.5 mm, and the second insulating component 15 covers the end of the second electrode diaphragm 132 by L5 = 0.5 mm. A third insulating element 16 is disposed on the first portion 1131 of the first lead 113. A first insulating element 14 covers the third insulating element 16 for a third length L6 = 0.5 mm. A fourth insulating element 17 is disposed on the first portion 1131 of the second lead 133. A second insulating element 15 covers the fourth insulating element 17 for a third length L7 = 0.5 mm. The first electrode 11 is linear, with a diameter d5 = 300 μm. The ratio of the diameter d1 of the first lead 113 to the diameter d2 of the first current collector 111 is d1 / d2 = 3. The second electrode 13 is sheet-like, with a thickness d6 = 300 μm. The ratio of the thickness d3 of the second lead 133 to the thickness d4 of the second current collector 131 is d3 / d4 = 3. The tensile strength of the first electrode 11 is 70 MPa, and the elongation at break is 4%. The tensile strength of the second electrode 13 is 65 MPa, and the elongation at break is 5%.

[0092] Example 2 This embodiment is based on Embodiment 1, except that A1 / A2=0.1, L1=2 mm, L2=10 mm, L3=50 cm, L1 / L3=0.004, L2 / L3=0.2, D=0.15 mm, L4=0.2 mm, L5=0.2 mm, L6=1 mm, L7=1 mm, d1 / d2=1, d5=50 μm, d3 / d4=1, d6=50 μm, the tensile strength of the first electrode 11 is 50 MPa, and the elongation at break is 6%. The tensile strength of the second electrode 13 is 50 MPa, and the elongation at break is 6%.

[0093] Example 3 This embodiment is based on Embodiment 1, except that A1 / A2=0.95, L1=10 mm, L2=2 mm, L3=5 cm, L1 / L3=0.2, L2 / L3=0.04, D=1 mm, L4=1 mm, L5=1 mm, L6=0.2 mm, L7=0.2 mm, d1 / d2=5, d5=500 μm, d3 / d4=5, d6=500 μm, the tensile strength of the first electrode 11 is 100 MPa, and the elongation at break is 1%. The tensile strength of the second electrode 13 is 100 MPa, and the elongation at break is 1%.

[0094] Example 4 This embodiment is based on Embodiment 1, except that A1 / A2=0.7, L1=3 mm, L2=8 mm, L3=35 cm, L1 / L3=0.09, L2 / L3=0.023, D=0.5 mm, L4=0.5 mm, L5=0.5 mm, L6=0.5 mm, L7=0.5 mm, d1 / d2=3, d3 / d4=3, d6=300 μm.

[0095] Example 5 This embodiment is based on Embodiment 1, except that L1 = 1 mm.

[0096] Example 6 This embodiment is based on Embodiment 1, except that L1 = 12 mm and L1 > L2.

[0097] Example 7 This embodiment is based on Embodiment 1, except that L2 = 1 mm and L1 > L2.

[0098] Example 8 This embodiment is based on Embodiment 1, except that L2 = 12 mm.

[0099] Example 9 This embodiment is based on Embodiment 1, except that L3 = 3 mm.

[0100] Example 10 This embodiment is based on Embodiment 1, except that L3 = 60 mm.

[0101] Comparative Example 1 This embodiment is based on Embodiment 1, except that A1 / A2 = 1.1.

[0102] Material property testing 1. Test method for 1000T cycle capacity retention: Experimental steps: Conduct the experiment at 25℃±+5℃ using the following steps: a. Charge at a constant current rate of 0.2C, cut off at a current rate of 0.05C, and then discharge at a constant current rate of 0.2C, with a voltage range of 2.0 V to 4.3 V. This constitutes one charge-discharge cycle.

[0103] b. Record the discharge capacity Q1 in week 1.

[0104] c. Preparation of circulating fixture: Prepare a contouring fixture with a central angle of 180° according to the curvature of the product. The contouring fixture has built-in foam to ensure that the contouring fixture can maintain the curvature of the product while also allowing the battery to expand and release with a diameter of 100 mm.

[0105] d. Fix the battery 100 sample, after one charge-discharge cycle, onto the contour jig and bend it according to the curvature of the contour jig.

[0106] e. Perform the inspection cycle according to the cycle system in step a. After 1000 cycles, record the discharge capacity Q1000 in the 1000th cycle. Calculate the cycle capacity retention rate of the battery after 100 cycles by Q1000 / Q1×100%.

[0107] 2. Energy density test Battery 100 is charged at a current of 0.2C to a limiting voltage, then charged at a constant voltage until the current decreases to 0.02C. It is then discharged at a current of 0.2C to a limiting voltage, and the energy discharged is denoted as E. The dimensions of battery 100 are measured and calculated (e.g., the thickness, width, and length of battery 100 are measured and their product is calculated), and the volume of battery 100 is denoted as V. The volumetric energy density V is... ED =E / V. At least three samples should be tested and the average value taken.

[0108] 3. Battery electrode breakage rate after 100 cycles The sample size of each embodiment and comparative test battery 100 was 10 units. Cyclic testing was conducted according to the 1000T cycle capacity retention rate test method described above. After the cycle test, the lithium-ion battery 100 was disassembled, and a visual inspection was performed to record whether the first electrode 11 and the second electrode 13 showed cracks, partial fractures, or complete fractures. It should be noted that the presence of cracks, partial fractures, or complete fractures in either the first electrode 11 or the second electrode 13 of the battery 100 is considered as a fracture of the battery 100 after cycling. 1 / 10 indicates that one out of the ten tested batteries 100 fractured.

[0109] Table 1 shows the test results.

[0110] Table 1

Claims

1. A battery, characterized in that, include: A housing and a battery cell, wherein the housing has a receiving cavity and the battery cell is disposed within the receiving cavity; The battery cell includes a first electrode and a second electrode, at least one of the first electrode and the second electrode is linear, an insulating layer is disposed between the first electrode and the second electrode, the first electrode is the negative electrode and the second electrode is the positive electrode; The first electrode includes a first current collector extending along a first direction and a first electrode diaphragm formed on the outside of the first current collector; The second electrode includes a second current collector extending along the first direction and a second electrode diaphragm formed on the outside of the second current collector; The second electrode is wound around the first electrode, wherein, Along the first direction, the end of the first current collector is provided with a negative electrode empty foil region, and the first electrode further includes a first lead wire connected to the negative electrode empty foil region. The end of the second current collector is provided with a positive electrode empty foil region, and the second electrode further includes a second lead wire connected to the positive electrode empty foil region. The area of ​​the positive electrode empty foil region is A1, and the area of ​​the negative electrode empty foil region is A2. A1 and A2 satisfy: A1 / A2 < 1.

2. The battery according to claim 1, characterized in that, Along the first direction, the length of the positive electrode empty foil region is L1, wherein L1 satisfies: 2 mm ≤ L1 ≤ 10 mm; and / or The length of the negative electrode empty foil region is L2, and L2 satisfies: 2 mm ≤ L2 ≤ 10 mm; And / or, L1 and L2 satisfy: L1≤L2.

3. The battery according to claim 2, characterized in that, The length of the battery is L3, which is 5 cm to 50 cm. The relationship between L1 and L3 satisfies: 0.004 ≤ L1 / L3 ≤ 0.2, and / or The L2 and L3 satisfy the condition: 0.004≤L2 / L3≤0.

2.

4. The battery according to claim 1, characterized in that, Along the second direction, there is a distance D between the positive electrode empty foil region and the negative electrode empty foil region, where D > 0.1 mm, and the second direction is perpendicular to the first direction.

5. The battery according to claim 1, characterized in that, The first lead is riveted, hinged, welded, or bonded to the negative electrode empty foil area; and / or The second lead is riveted, hinged, welded, or bonded to the positive electrode empty foil area.

6. The battery according to claim 5, characterized in that, The connection portion of the first lead and the negative electrode empty foil region forms a first connection area, and a first insulating element is disposed on the first connection area. The connection portion of the second lead and the positive electrode empty foil region forms a second connection area, and a second insulating element is disposed on the second connection area. The first insulating element extends to cover the end of the first electrode diaphragm by a first length L4, where L4 is 0.2 mm to 1 mm; and / or, The second insulating element extends to cover the end of the second electrode diaphragm by a second length L5, wherein L5 is 0.2 mm to 1 mm.

7. The battery according to claim 6, characterized in that, The first lead includes a first portion extending out of the housing along the first direction, the first portion being located on the side of the first connection region away from the first electrode diaphragm, and a third insulating member is formed on the first portion, at least a portion of the third insulating member being bonded to the housing. The second lead includes a second portion extending out of the housing along the first direction, the second portion being located on the side of the second connection region away from the second electrode diaphragm, and a fourth insulating member is formed on the second portion, at least a portion of the fourth insulating member being bonded to the housing. The first insulating member covers the third insulating member by a third length L6 along the first direction, where L6 is 0.2 mm to 1 mm; and / or The second insulating member covers the fourth insulating member by a length of L7, which is 0.2 mm to 1 mm.

8. The battery according to claim 1, characterized in that, The first electrode is linear, the diameter and / or thickness of the first lead is d1, and the diameter of the first current collector is d2, wherein d1 and d2 satisfy: 1 ​​≤ d1 / d2 ≤ 5, and / or The diameter d5 of the first electrode is 50 μm to 500 μm; and / or The second electrode is linear, the diameter or thickness of the second lead is d3, and the diameter of the second current collector is d4, wherein d3 and d4 satisfy: 1 ​​≤ d3 / d4 ≤ 5, and / or The diameter d6 of the second electrode is 50 μm to 500 μm; and / or The tensile strength of the first electrode and / or the second electrode is ≥50 MPa, and / or The elongation at break of the first electrode and / or the second electrode is ≥1%.

9. The battery according to claim 1, characterized in that, The housing has a first surface and a second surface, the first surface facing the battery cell and the second surface away from the battery cell. At least a polymer layer is disposed on each of the first and second surfaces. The polymer layers are bonded and sealed along the first direction to form the housing. The first lead and the second lead extend from the housing. Preferably, The polymer layer includes one or more of polyethylene, polypropylene, a copolymer of polypropylene and acrylic acid, a copolymer of polyethylene and acrylic acid, polyvinyl chloride, a terpolymer of polypropylene-butene-ethylene, and a copolymer of ethylene and propylene.

10. The battery according to any one of claims 1 to 9, characterized in that, The first electrode is linear, the diameter and / or thickness of the first lead is d1, and the diameter of the first current collector is d2, wherein d1 and d2 satisfy: 1 ​​≤ d1 / d2 ≤ 5, and / or The diameter d5 of the first electrode is 50 μm to 500 μm; and / or The second electrode is sheet-shaped, the diameter or thickness of the second lead is d3, and the thickness of the second current collector is D4, wherein d3 and D4 satisfy: 1≤d3 / D4≤5, and / or The thickness D6 of the second electrode is 50 μm to 500 μm; and / or The tensile strength of the first electrode and / or the second electrode is ≥50 MPa, and / or The elongation at break of the first electrode and / or the second electrode is ≥1%.

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