Tab insulating film, battery top cover assembly and battery

Abstract

The application belongs to the technical field of batteries, and particularly relates to a tab insulation film, a battery top cover assembly and a battery. The tab insulation film comprises a hot melt fixing layer, an intermediate bonding layer arranged on the surface of the hot melt fixing layer, and a high-temperature-resistant insulation layer arranged on the surface of the side of the intermediate bonding layer away from the hot melt fixing layer. The ratio of the thickness of the hot melt fixing layer, the thickness of the intermediate bonding layer and the thickness of the high-temperature-resistant insulation layer is (1-3):1:(1-5). The tab insulation film has good high-temperature resistance, insulation and reliable hot melt fixing, and can effectively isolate the tab and the battery cell body under high-temperature working conditions, preventing the tab from being directly overlapped with the shell to cause electrochemical corrosion.

Description

Technical Field

[0001] This application belongs to the field of battery technology, specifically relating to a tab insulating film, a battery top cover assembly, and a battery. Background Technology

[0002] Currently, electrode insulating films mostly use single-layer pure polypropylene (PP) films, single-layer pure polyimide (PI) films, or composite structures of homogeneous materials (such as direct hot-pressing of multiple PI films). These solutions offer relatively limited functionality and struggle to simultaneously achieve excellent high-temperature resistance and insulation performance. When the battery cell is under high-temperature conditions, conventional PP materials are prone to melting and softening, easily causing the insulation structure to fail and posing safety hazards. PI films have no fixed melting point and typically do not melt at high temperatures, thus they cannot be heat-fused to the underlying plastic, hindering proper assembly and use. Therefore, electrode insulating films require further improvement. Summary of the Invention

[0003] This application aims to at least partially solve one of the technical problems in the related art. To this end, this application proposes an electrode insulating film with good high temperature resistance, insulation and reliable heat-melt fixation, which can effectively isolate the electrode from the battery casing under high temperature conditions and prevent electrochemical corrosion caused by direct contact between the electrode and the casing.

[0004] A first aspect of this application provides a tab insulating film, comprising: Hot melt fixing layer; An intermediate bonding layer is disposed on the surface of the hot-melt fixing layer; A high-temperature resistant insulating layer is disposed on the surface of the intermediate bonding layer away from the hot-melt fixing layer; The ratio of the thickness of the hot-melt fixing layer, the thickness of the intermediate bonding layer, and the thickness of the high-temperature resistant insulating layer is (1 ~ 3): 1: (1 ~ 5).

[0005] This application uses an intermediate bonding layer to firmly bond the heat-melt fixing layer (PP) and the high-temperature resistant insulating layer (PI) into one unit, forming an asymmetric three-layer structure. The heat-melt fixing layer has good mechanical strength and insulation properties, enabling reliable heat-melt fixing with the underlying plastic; the high-temperature resistant insulating layer has good mechanical strength, insulation properties, and high-temperature resistance, thus maintaining structural stability and insulation properties under high-temperature environments and preventing short circuits between the tab and the encapsulation material; the intermediate bonding layer enables a strong bond between the two. Furthermore, within the aforementioned thickness ratio range, the thicknesses of the three layers are matched and work synergistically, achieving a good balance between high-temperature resistance, insulation properties, and heat-melt fixing effect in the tab insulating film. Applying the tab insulating film to batteries can effectively isolate the tab from the cell casing under high-temperature conditions, preventing electrochemical corrosion caused by direct contact between the tab and the casing.

[0006] According to embodiments of this application, the above-mentioned tab insulating film satisfies at least one of the following conditions: The thickness of the hot-melt fixing layer is 5μm~150μm; The thickness of the intermediate bonding layer is 5μm~50μm; The thickness of the high-temperature resistant insulating layer is 5μm~250μm.

[0007] According to embodiments of this application, the above-mentioned tab insulating film satisfies at least one of the following conditions: The material of the hot-melt fixing layer is selected from at least one of polypropylene, polyethylene, polyvinyl chloride, and ethylene propylene rubber; The material of the intermediate bonding layer is selected from at least one of acrylic resin, epoxy resin, and polyurethane resin. The material of the high-temperature resistant insulation layer is selected from at least one of polyimide, polyamide-imide, polyetheretherketone, and fluoroplastics.

[0008] According to an embodiment of this application, at least four hot-melt positions are provided on the side surface of the hot-melt fixing layer away from the intermediate bonding layer, and the hot-melt positions are uniformly distributed along the circumference of the hot-melt fixing layer.

[0009] According to an embodiment of this application, the above-mentioned tab insulating film is provided with: An explosion-proof valve clearance groove is provided in the central area of ​​the electrode tab insulation film to avoid the explosion-proof valve protrusion; Two perforated clearance slots are symmetrically arranged on both sides of the longitudinal edge of the electrode insulating film; Positioning holes are symmetrically arranged on the central axis of the tab insulating film in the width direction.

[0010] According to an embodiment of this application, the shape of the explosion-proof valve vent groove is selected from any one of the following: elongated strip type with side round holes, cross-shaped convex petal type, and single-sided convex lug type.

[0011] According to embodiments of this application, the above-mentioned tab insulating film satisfies at least one of the following conditions: The length D1 of the explosion-proof valve's vent groove satisfies: D2+2 ≤ D1 ≤ D2+8; The width L1 of the explosion-proof valve's vent groove satisfies: L2+2 ≤ L1 ≤ L2+8; Where D2 is the length of the explosion-proof valve boss in mm, and L2 is the width of the explosion-proof valve boss in mm.

[0012] According to embodiments of this application, the above-mentioned tab insulating film satisfies at least one of the following conditions: The length D3 of the electrode insulating film satisfies: D4-8 ≤ D3 ≤ D4-2; The width L3 of the electrode insulating film satisfies: L3 ≥ L4 + 20 mm; Where D4 is the minimum spacing of the lower plastic edge support bosses in mm, and L4 is the width of the lower plastic in mm.

[0013] According to embodiments of this application, the above-mentioned tab insulating film satisfies at least one of the following conditions: The radius R1 of a single perforated clearance groove satisfies: R2+0.1≤ R1 ≤R2+2, where R2 is the radius of the through hole on the lower plastic post in mm; The center distance D5 between the two perforated clearance slots is equal to the center distance D6 between the pole posts.

[0014] According to an embodiment of this application, the electrode insulating film is sleeved on the electrode through a perforated groove, and the two ends of the electrode insulating film in the width direction extend to the side of the battery cell.

[0015] The insulating film of the electrode is sleeved on the electrode through a perforated groove, forming an insulating layer between the electrode and the cell. This effectively isolates the electrode and the cell casing under high-temperature conditions, preventing direct contact between the electrode and the casing and electrochemical corrosion. It also effectively prevents internal short circuits in the battery, thereby improving the battery's safety performance and service life.

[0016] A second aspect of this application provides a battery top cover assembly, comprising: Bright aluminum sheet; The lower plastic is disposed on the surface of the aluminum sheet near the battery cell. The tab insulating film described in the first aspect is disposed on the surface of the lower plastic near the battery cell.

[0017] The battery top cover assembly includes all the features and advantages of the tab insulating film described in the first aspect, which will not be repeated here.

[0018] According to an embodiment of this application, the electrode includes a first electrode and a second electrode, and the electrode insulating film has a first end and a second end disposed opposite to each other along the length direction of the aluminum sheet; Along the length of the aluminum sheet, the first end extends beyond the first tab and is farther away from the second tab, and the second end extends beyond the second tab and is farther away from the first tab.

[0019] A third aspect of this application provides a battery comprising the battery top cover assembly described in the second aspect. This battery includes all the features and advantages of the battery top cover assembly described in the second aspect, which will not be elaborated upon here. Attached Figure Description

[0020] Figure 1 This is a schematic cross-sectional view of the tab insulating film according to an embodiment of this application.

[0021] Figure 2 This is a schematic diagram showing the location of the heat-melting position according to an embodiment of this application.

[0022] Figure 3 This is a schematic diagram of the structure of the tab insulating film according to an embodiment of this application.

[0023] Figure 4 This is a schematic diagram of the structure of the tab insulating film according to another embodiment of this application.

[0024] Figure 5 This is a schematic diagram of the structure of a battery top cover assembly according to an embodiment of this application.

[0025] Figure 6 This is a front view of a battery cell according to an embodiment of this application.

[0026] Figure 7 This is an isometric view of a battery cell according to an embodiment of this application.

[0027] Reference numerals: 10: Insulating film for electrode tabs; 101: Hot-melt fixing layer; 102: Intermediate bonding layer; 103: High-temperature resistant insulating layer; 104: Hot-melt position; 105: Explosion-proof valve anti-cavity groove; 106: Perforated anti-cavity groove; 107: Positioning hole; 20: Battery top cover assembly; 201: Plain aluminum sheet; 202: Lower plastic; 31: First electrode tab; 32: Second electrode tab; A1: First end; A2: Second end. Detailed Implementation

[0028] The embodiments of this application are described in detail below, with examples of these embodiments illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0029] Currently, the insulating film for electrode tabs mainly uses single polypropylene (PP) film or single polyimide (PI) film. While single PP film has good heat-melting properties, allowing it to be heat-fused and fixed to the underlying plastic at battery encapsulation temperatures, PP has poor temperature resistance, with long-term operating temperatures typically below 101℃. Under abnormally high-temperature conditions such as battery overcharging or short circuits, it is prone to softening or even melting, posing a safety hazard. Single PI film has excellent high-temperature resistance (long-term operating temperature can reach above 103℃) and high insulation strength, but PI film has no fixed melting point and typically does not melt at high temperatures. Therefore, it cannot be heat-fused and fixed to the underlying plastic, making normal assembly and use impossible.

[0030] Based on the above, the first aspect of this application proposes an electrode insulating film 10, with reference to... Figure 1 The electrode insulation 10 includes: Hot melt fixing layer 101; An intermediate bonding layer 102 is disposed on the surface of the hot-melt fixing layer 101; A high-temperature resistant insulating layer 103 is disposed on the surface of the intermediate bonding layer 102 away from the hot-melt fixing layer 101; The ratio of the thickness of the hot-melt fixing layer 101, the thickness of the intermediate bonding layer 102, and the thickness of the high-temperature resistant insulating layer 103 is (1 ~ 3): 1: (1 ~ 5).

[0031] This application uses an intermediate bonding layer to firmly bond the heat-melt fixing layer (PP) and the high-temperature resistant insulating layer (PI) into one unit, forming an asymmetric three-layer structure. The heat-melt fixing layer has good mechanical strength and insulation properties, enabling reliable heat-melt fixing with the underlying plastic; the high-temperature resistant insulating layer has good mechanical strength, insulation properties, and high-temperature resistance, thus maintaining structural stability and insulation properties in high-temperature environments and preventing short circuits between the tab and the encapsulation material; the intermediate bonding layer enables a strong bond between the two. Furthermore, within the aforementioned thickness ratio range, the thicknesses of the three layers are matched and work synergistically, achieving a good balance between high-temperature resistance, insulation properties, and heat-melt fixing effect in the tab insulating film.

[0032] According to embodiments of this application, the thickness of the hot-melt fixing layer 101 is 5μm to 150μm, specifically 5μm, 10μm, 20μm, 50μm, 80μm, 100μm, 130μm, and 150μm. Within this range, the hot-melt fixing layer has good structural strength and insulation properties. Excessive thickness may lead to bending cracks and excessive mechanical strength redundancy.

[0033] According to an embodiment of this application, the material of the hot-melt fixing layer 101 is selected from at least one of polypropylene (PP), polyethylene (PE), polyvinyl chloride (PVC), and ethylene propylene diene monomer (EPDM). The above materials have excellent chemical stability and insulation properties, which can effectively isolate the electrode tab from the external circuit, and the flame retardant rating meets UL 94 (V-0 rating), and can work for a long time at 101℃~150℃. In addition, the properties of the above materials are similar to those of the lower plastic, so reliable hot-melt fixing with the lower plastic can be further achieved.

[0034] According to embodiments of this application, the thickness of the intermediate bonding layer 102 is 5μm to 50μm, specifically within the range of 5μm, 7μm, 10μm, 20μm, 30μm, 40μm, 50μm, or any two of these ranges. Within this range, the impact on overall insulation and thermal conductivity can be reduced while ensuring bonding strength.

[0035] According to embodiments of this application, the intermediate bonding layer 102 is made of at least one of acrylic adhesive, epoxy resin adhesive, and polyurethane (PU) adhesive. These materials possess high adhesive strength, enabling them to firmly bond the hot-melt fixing layer with significant polarity differences to the high-temperature resistant insulating layer. Furthermore, these materials can resist long-term chemical corrosion from electrolytes and maintain their adhesive strength even after immersion.

[0036] According to embodiments of this application, the thickness of the high-temperature resistant insulating layer 103 is 5μm to 250μm, specifically within the range of 5μm, 10μm, 20μm, 40μm, 60μm, 80μm, 100μm, 120μm, 150μm, 180μm, 200μm, 250μm, or any two of these ranges. Within this range, the thickness is sufficient to ensure insulation strength and high-temperature resistance, while not being too thick would increase costs.

[0037] According to embodiments of this application, the high-temperature resistant insulating layer 103 is made of at least one material selected from polyimide, polyamide-imide, polyetheretherketone, and fluoroplastics. The aforementioned materials meet the UL 94 (V-0) flame retardancy rating, can operate normally at high temperatures of 102℃~103℃ for extended periods, possess excellent mechanical strength and insulation properties, and can well meet the requirements for use within the battery cell.

[0038] According to embodiments of this application, fluoroplastics are a general term for a class of synthetic polymers whose main molecular chain contains fluorine atoms, also known as fluoropolymers. Fluoroplastics include, but are not limited to, polytetrafluoroethylene (PTFE).

[0039] According to the embodiments of this application, referring to Figure 2 The hot-melt fixing layer 101 has at least four hot-melt positions 104 on its surface away from the intermediate bonding layer 102, and these hot-melt positions are evenly distributed circumferentially along the hot-melt fixing layer. This multi-point uniform distribution allows for the formation of a multi-point, uniform hot-melt connection during thermo-press sealing, reducing the possibility of poor sealing or film deformation, ensuring the uniformity and reliability of the hot-melt connection, and simultaneously preventing electrolyte leakage or external moisture intrusion. As a specific example, four hot-melt positions can be provided, and these four hot-melt points are centrally symmetrically distributed around the center point of the hot-melt fixing layer.

[0040] According to the embodiments of this application, referring to Figure 3 The electrode insulating film is provided with: An explosion-proof valve clearance groove 105 is provided in the central area of ​​the electrode tab insulating film to avoid the explosion-proof valve boss; Perforated clearance grooves 106 are symmetrically arranged on both sides of the electrode insulating film along its length. Positioning holes 107 are symmetrically arranged on the central axis of the tab insulating film in the width direction.

[0041] The explosion-proof valve anti-cavity groove prevents the tab insulation film from covering or obstructing the explosion-proof structure, ensuring that the explosion-proof structure can open normally to release pressure when the battery's internal pressure rises abnormally, preventing the risk of battery explosion caused by the tab insulation film obstructing the flow; the perforated anti-cavity groove is used to avoid the perforated structure at the tab lead-out position; the positioning hole enables the precise assembly and fixation of the tab insulation film, improving product manufacturing yield and safety.

[0042] According to an embodiment of this application, the shape of the explosion-proof valve vent groove is selected from any one of the following: elongated strip type with side round holes, cross-shaped convex petal type, and single-sided convex lug type.

[0043] Reference Figure 3 The shape and size of the vent groove for explosion-proof valves can be designed according to the shape and size of the explosion-proof valve. For example, refer to... Figure 3 In (a), the explosion-proof valve vent groove adopts a long strip shape with side round holes.

[0044] Reference Figure 3 In (b), the explosion-proof valve's vent groove adopts a cross-shaped convex petal design. The solid line is the outer opening edge of the vent groove of the electrode insulating film, and the dashed line is the inner contour edge of the narrowed interior of the explosion-proof valve. The entire inner contour is contained within the opening area of ​​the insulating film.

[0045] Reference Figure 3 In (c), the explosion-proof valve's vent groove adopts a single-sided lug-shaped irregular shape. The solid line is the outer opening edge of the vent groove of the electrode insulating film, and the dashed line is the inner contour edge of the narrowed interior of the explosion-proof valve. The entire inner contour is contained within the opening area of ​​the insulating film.

[0046] According to the embodiments of this application, referring to Figure 4 The length D1 of the explosion-proof valve's vent groove satisfies: D2+2 ≤ D1 ≤ D2+8, where D2 is the length of the explosion-proof valve's boss in mm. The vent groove length D1 satisfies the above condition, ensuring that the vent groove completely covers the explosion-proof valve's boss, providing a margin for heat-sealing and guaranteeing unobstructed pressure relief.

[0047] According to an embodiment of this application, the length D1 of the explosion-proof valve's vent groove satisfies: 5mm ≤ D1 ≤ 40mm. Sufficient venting space is provided to prevent components from obstructing the explosion-proof valve and to ensure smooth pressure relief.

[0048] According to the embodiments of this application, referring to Figure 4 The width L1 of the explosion-proof valve's clearance groove satisfies: L2+2 ≤ L1 ≤ L2+8, where L2 is the width of the explosion-proof valve boss in mm. The clearance groove width L1 satisfies the above condition, ensuring that the clearance groove completely avoids the explosion-proof valve boss in the width direction, reducing interference between the electrode insulating film and the boss edge, and improving packaging compatibility and yield.

[0049] According to an embodiment of this application, the width L1 of the explosion-proof valve's venting groove satisfies: 50mm ≤ L1 ≤ 300mm. Within this range, the exhaust cross-sectional area and the structural strength of the cover plate can be balanced, preventing the cover plate from deforming due to insufficient rigidity caused by an excessively wide groove.

[0050] According to the embodiments of this application, referring to Figure 4 The length D3 of the tab insulating film satisfies: D4-8 ≤ D3 ≤ D4-2, where D4 is the minimum spacing (mm) of the lower plastic edge support bosses. The length D3 of the tab insulating film satisfies this condition, ensuring that the edge of the tab insulating film does not exceed the range of the lower plastic edge support bosses, thus reducing the possibility of the tab insulating film edge contacting the shell during hot pressing.

[0051] According to an embodiment of this application, the length D3 of the tab insulating film satisfies: 50mm ≤ D3 ≤ 250mm. Within this range, sufficient length ensures that the tab insulating film completely covers the root of the tab, thereby reducing the risk of short circuit.

[0052] According to the embodiments of this application, referring to Figure 4 The width L3 of the tab insulating film satisfies: L3 ≥ L4 + 20 mm, where L4 is the width of the lower plastic film in mm. The width L3 of the tab insulating film satisfies the above condition, allowing both ends of its width direction to extend to the side of the battery cell, achieving effective insulation between the tab and the battery cell body, and preventing short circuits between the tab and the battery cell housing.

[0053] According to an embodiment of this application, the width L3 of the tab insulating film ranges from 50mm to 300mm. Within this range, sufficient width can isolate the tab from the battery casing, preventing top seal corrosion and micro-short circuits.

[0054] According to the embodiments of this application, referring to Figure 4 The radius R1 of a single perforated clearance groove satisfies: R2+0.1≤ R1 ≤R2+2, where R2 is the radius of the through hole on the lower plastic post in mm. The radius R1 of the perforated clearance groove satisfies the above condition, creating a gap between the perforated clearance groove and the through hole on the post. This ensures that the post can pass through smoothly while preventing the gap from being too large, which would result in insufficient insulation coverage.

[0055] According to an embodiment of this application, the radius R1 of a single perforated clearance groove satisfies: 5mm ≤ R1 ≤ 50mm. Within this range, sufficient space is reserved for welding the pole and connecting piece, while also covering as much of the lower plastic and pole tab surface as possible, improving insulation and isolation effects.

[0056] According to the embodiments of this application, referring to Figure 4The center distance D5 between the two perforated clearance slots equals the center distance D6 between the pole posts. Meeting these conditions ensures that the perforated clearance slots on the electrode tab insulation film are concentrically aligned with the through holes in the pole posts, guaranteeing that the pole posts can accurately pass through the perforated clearance slots, preventing electrode tab bending, and improving assembly accuracy and electrode tab lead-out reliability.

[0057] According to an embodiment of this application, the tab insulating film 10 is sleeved on the tab through a perforated groove, and both ends of the tab insulating film 10 in the width direction extend to the side of the battery cell.

[0058] The insulating film of the electrode is sleeved on the electrode through a perforated groove, forming an insulating layer between the electrode and the cell. This effectively isolates the electrode from the battery casing under high-temperature conditions, preventing direct contact between the electrode and the casing and causing electrochemical corrosion. It also effectively prevents internal short circuits in the battery, thereby improving the battery's safety performance and service life.

[0059] A second aspect of this application provides a battery top cover assembly 20, with reference to... Figure 5 The battery top cover assembly 20 includes: 201 light aluminum sheet; The lower plastic 202 is disposed on the surface of the aluminum sheet 201 near the battery cell; The tab insulating film 10 described in the first aspect is disposed on the side surface of the lower plastic 202 near the battery cell.

[0060] The battery top cover assembly includes all the features and advantages of the tab insulating film described in the first aspect, which will not be repeated here.

[0061] According to the embodiments of this application, referring to Figure 6 and Figure 7 The electrode includes a first electrode 31 and a second electrode 32. The electrode insulating film 10 has a first end A1 and a second end A2 that are disposed opposite to each other along the length direction of the light aluminum sheet. Along the length direction of the light aluminum sheet, the first end A1 extends beyond the end of the first electrode 31 that is away from the second electrode 32, and the second end A2 extends beyond the end of the second electrode 32 that is away from the first electrode 31.

[0062] "Exceeding" means that, along the length of the aluminum sheet, the end edge of the insulating film of the electrode is located outside the end edge of the electrode, and there is a predetermined distance between the two along the length.

[0063] A third aspect of this application provides a battery comprising the battery top cover assembly described in the second aspect. This battery includes all the features and advantages of the battery top cover assembly described in the second aspect, which will not be elaborated upon here.

[0064] The types of batteries may include, but are not limited to, lithium-ion batteries, sodium-ion batteries, sodium-lithium-ion batteries, lithium metal batteries, sodium metal batteries, lithium-sulfur batteries, magnesium-ion batteries, sulfide batteries, oxide batteries, polymer batteries, halide batteries, nickel-metal hydride batteries, nickel-cadmium batteries, lead-acid batteries, etc. The embodiments of this application do not limit the types of batteries.

[0065] 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.

[0066] 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.

[0067] 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.

[0068] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example 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.

[0069] 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.

Claims

1. A tab insulating film, characterized in that, include: Hot melt fixing layer; An intermediate bonding layer is disposed on the surface of the hot-melt fixing layer; A high-temperature resistant insulating layer is disposed on the surface of the intermediate bonding layer away from the hot-melt fixing layer; The ratio of the thickness of the hot-melt fixing layer, the thickness of the intermediate bonding layer, and the thickness of the high-temperature resistant insulating layer is (1~3):1:(1~5).

2. The electrode insulating film according to claim 1, characterized in that, At least one of the following conditions must be met: The thickness of the hot-melt fixing layer is 5μm~150μm; The thickness of the intermediate bonding layer is 5μm~50μm; The thickness of the high-temperature resistant insulating layer is 5μm~250μm.

3. The electrode insulating film according to claim 1, characterized in that, At least one of the following conditions must be met: The material of the hot-melt fixing layer is selected from at least one of polypropylene, polyethylene, polyvinyl chloride, and ethylene propylene rubber; The material of the intermediate bonding layer is selected from at least one of acrylic resin, epoxy resin, and polyurethane resin. The material of the high-temperature resistant insulation layer is selected from at least one of polyimide, polyamide-imide, polyetheretherketone, and fluoroplastics.

4. The electrode insulating film according to claim 1, characterized in that, The hot-melt fixing layer has at least four hot-melt positions on the side surface away from the intermediate bonding layer, and the hot-melt positions are evenly distributed along the circumference of the hot-melt fixing layer.

5. The electrode insulating film according to claim 1, characterized in that, The electrode insulating film is provided with: An explosion-proof valve clearance groove is provided in the central area of ​​the electrode tab insulation film to avoid the explosion-proof valve protrusion; Two perforated clearance slots are symmetrically arranged on both sides of the longitudinal edge of the electrode insulating film; Positioning holes are symmetrically arranged on the central axis of the tab insulating film in the width direction.

6. The electrode insulating film according to claim 5, characterized in that, The shape of the explosion-proof valve's vent groove is selected from any one of the following: long strip with side round holes, cross-shaped convex petals, or single-sided convex lug.

7. The electrode insulating film according to claim 6, characterized in that, At least one of the following conditions must be met: The length D1 of the explosion-proof valve's vent groove satisfies: D2+2 ≤ D1 ≤ D2+8; The width L1 of the explosion-proof valve's vent groove satisfies: L2+2 ≤ L1 ≤ L2+8; Where D2 is the length of the explosion-proof valve boss in mm, and L2 is the width of the explosion-proof valve boss in mm.

8. The electrode insulating film according to claim 1, characterized in that, At least one of the following conditions must be met: The length D3 of the electrode insulating film satisfies: D4-8 ≤ D3 ≤ D4-2; The width L3 of the electrode insulating film satisfies: L3 ≥ L4 + 20 mm; Where D4 is the minimum spacing of the lower plastic edge support bosses in mm, and L4 is the width of the lower plastic in mm.

9. The electrode insulating film according to claim 5, characterized in that, At least one of the following conditions must be met: The radius R1 of a single perforated clearance groove satisfies: R2+0.1≤ R1 ≤R2+2, where R2 is the radius of the through hole on the lower plastic post in mm; The center distance D5 between the two perforated clearance slots is equal to the center distance D6 between the pole posts.

10. The electrode insulating film according to any one of claims 1 to 9, characterized in that, The electrode insulating film is sleeved on the electrode through a perforated groove, and both ends of the electrode insulating film in the width direction extend to the side of the battery cell.

11. A battery top cover assembly, characterized in that, include: Bright aluminum sheet; The lower plastic is disposed on the surface of the aluminum sheet near the battery cell. The tab insulating film according to any one of claims 1 to 10, wherein the tab insulating film is disposed on the surface of the lower plastic near the battery cell.

12. The battery top cover assembly according to claim 11, characterized in that, The electrode includes a first electrode and a second electrode. The electrode insulating film has a first end and a second end that are disposed opposite to each other along the length direction of the aluminum sheet. Along the length direction of the aluminum sheet, the first end extends beyond the end of the first electrode that is away from the second electrode, and the second end extends beyond the end of the second electrode that is away from the first electrode.

13. A battery, characterized in that, Includes the battery top cover assembly as described in claim 11 or 12.

Images