Insulating structure and battery cell

Abstract

The application relates to an insulation structure and a battery monomer. The insulation structure comprises an upper film matched with and covering a top surface, the upper film being provided with a first through hole for avoiding a tab; a side film extending along a first direction at two side edges of the upper film to cover a side surface; and a bottom film extending along the first direction at the end of the side film to cover a bottom surface. A frame assembly comprises a first frame and a window door, the first frame being connected to the upper film and provided with a second through hole matched with the first through hole, and the window door being connected to the first frame in an openable and closable mode and pressing against the surface of the tab in a closed state to limit the tab in the first through hole. The insulation structure can not only limit the position of the tab, greatly reduce the tab folding and tearing, but also ensure the effective insulation and protection effect on the upper side of the electrode assembly. In addition, the mechanical fixing mode of the frame assembly is used to replace the traditional hot melting process, so that the assembly effect and the structural reliability can be improved.

Description

Technical Field

[0001] This application relates to the field of lithium-ion battery technology, and in particular to an insulating structure and a battery cell. Background Technology

[0002] Lithium-ion batteries, as a major component of the new energy industry, have experienced rapid development in recent years, with various models emerging daily, such as cylindrical batteries, pouch batteries, and prismatic batteries. Among these, the prismatic battery is an important structural form among the three common types. In the production process of prismatic lithium-ion batteries, an insulating layer must be installed between the metal casing and the electrode assembly to prevent contact damage or short circuits caused by the casing, connecting pieces, cover plates, or terminals to the electrode assembly.

[0003] Currently, Mylar is widely used as a common form of insulation, protection, and fixing structural component. Mylar is wrapped around the outer surface of the electrode assembly and then fixed with a base plate. However, the electrode tabs need to extend from the top and be welded to the cover plate pole, thus requiring a large clearance area at the top of the Mylar. This clearance area can cause the electrode tabs to become misaligned during welding, resulting in tab folding or tearing. Utility Model Content

[0004] In view of this, the present application provides an insulating structure and a battery cell to solve at least one problem existing in the prior art.

[0005] In a first aspect, embodiments of this application provide an insulating structure for an electrode assembly, the electrode assembly having a top surface, a side surface, and a bottom surface, the top surface having an electrode tab; the insulating structure includes:

[0006] The upper membrane is adapted to and covers the top surface, and the upper membrane has a first through hole for avoiding the tab;

[0007] Side membranes extend along the first direction on both sides of the upper membrane and are adapted to fit the side surfaces for covering the side surfaces;

[0008] A bottom film extends along the first direction at the end of the side film and is adapted to fit the bottom surface for covering the bottom surface;

[0009] The frame assembly includes a first frame and a window / door. The first frame is connected to the upper membrane and has a second through hole adapted to the first through hole. The window / door is openable and closable and connected to the first frame. In the closed state, it presses against the surface of the electrode tab to confine the electrode tab within the first through hole. The first direction is the width direction of the upper membrane.

[0010] In conjunction with the first aspect of this application, in an alternative embodiment, the first frame is located on the side of the upper membrane facing the top surface;

[0011] The frame assembly also includes:

[0012] The second frame is provided on both sides of the upper film, and clamps and fixes the upper film.

[0013] In conjunction with the first aspect of this application, in an optional embodiment, the second frame has a third through hole, and the first frame and the second frame are fitted together by the inner wall of the third through hole abutting against the outer wall of the first frame; or the fitted together is achieved by the inner wall of the second through hole abutting against the outer wall of the second frame.

[0014] In conjunction with the first aspect of this application, in an optional embodiment, the first frame is provided with a first snap-fit ​​structure, and the window door is provided with a second snap-fit ​​structure adapted to the first snap-fit ​​structure. The window door is closed and locked to the first frame by the snap-fit ​​between the first snap-fit ​​structure and the second snap-fit ​​structure.

[0015] In conjunction with the first aspect of this application, in an optional embodiment, the first snap-fit ​​structure includes a groove provided in the first frame, and the second snap-fit ​​structure includes a protrusion provided on the side of the window door near the first frame, the protrusion being inserted into the groove so that the window door is locked to the first frame.

[0016] In conjunction with a first aspect of this application, in an optional embodiment, the sidewall includes two first sidewalls disposed opposite each other along the first direction and two second sidewalls disposed opposite each other along the second direction; the sidewall membrane includes:

[0017] A first side membrane extends along the first direction and covers the first side surface;

[0018] The second side membrane extends along the second direction to both sides of the first side membrane and covers the second side surface, where the second direction is the length direction of the upper membrane.

[0019] In conjunction with the first aspect of this application, in an optional embodiment, the top surface is provided with a pressure relief hole and / or a liquid injection hole; the upper membrane is provided with at least one fourth through hole to avoid the pressure relief hole and / or the liquid injection hole.

[0020] In conjunction with the first aspect of this application, in an optional embodiment, the insulating structure further includes:

[0021] The cornea extends along a second direction on both sides of the upper and lower membranes to cover the apex of the electrode assembly, wherein the second direction is the length direction of the upper membrane;

[0022] Indentations are provided at the connection points between the upper membrane and the side membrane, and between the side membrane and the bottom membrane, corresponding to the corners of the electrode assembly;

[0023] The upper film, the side film, and the bottom film are formed by folding an integrally molded film material, and the folding path coincides with the indentation.

[0024] In conjunction with the first aspect of this application, in an optional embodiment, when the electrode assembly is a monopole group, the window is connected to the frame of the first frame along the second direction;

[0025] When the electrode assembly is a multi-electrode group, the window is connected to the frame of the first frame along the first direction; wherein, the second direction is the length direction of the upper film.

[0026] Secondly, embodiments of this application provide a single battery cell, comprising:

[0027] An electrode assembly has a top surface, a side surface, and a bottom surface, wherein the top surface is provided with an electrode tab;

[0028] The insulation structure according to any one of the claims provided in the first aspect;

[0029] The housing has an accommodating space with an opening at one end, and the electrode assembly and the insulating structure are disposed within the accommodating space;

[0030] The upper film, the side film, and the bottom film respectively cover the top surface, the side surface, and the bottom surface. The first frame is connected to the upper film. The window is openable and closable and connected to the first frame, and presses against the surface of the electrode tab when closed.

[0031] The insulation structure and battery cell provided in this application embodiment not only restrict the position of the electrode tabs by setting the frame assembly at the first through hole of the upper film to avoid the electrode tabs, thus greatly reducing the possibility of electrode tabs folding or tearing, but also ensure the effective insulation protection effect on the upper side of the electrode assembly.

[0032] Furthermore, replacing the traditional hot-melt process with a mechanical fixing method for the frame components can improve the assembly effect and structural reliability.

[0033] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0034] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments of this application and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0035] Figure 1 This is a schematic diagram of the planar structure of the insulation structure provided in the embodiments of this application;

[0036] Figure 2 A schematic diagram of a battery cell equipped with an insulating structure;

[0037] Figure 3 for Figure 2 Enlarged view of point A in the middle;

[0038] Figure 4 This is an exploded view of the upper membrane and frame structure in the insulation structure provided in the embodiments of this application.

[0039] Figure 5 This is an exploded view of the upper membrane and frame structure in an insulating structure provided in another embodiment of this application;

[0040] Figure 6 A schematic diagram of a battery cell equipped with an insulating structure, provided for another embodiment of this application;

[0041] Figure 7 This is a schematic diagram of another state of a battery cell equipped with an insulating structure, provided for another embodiment of this application.

[0042] Figure label:

[0043] 100. Electrode assembly;

[0044] 1. Insulation structure;

[0045] 11. Upper membrane; 111. First through hole; 112. Fourth through hole; 12. Side membrane; 121. First side membrane; 122. Second side membrane; 13. Bottom membrane; 131. Siphon hole; 132. First bottom membrane; 133. Second bottom membrane;

[0046] 14. Frame assembly; 141. First frame; 1411. Second through hole; 1412. First snap-fit ​​structure; 1413. Groove; 142. Window / door; 1421. Second snap-fit ​​structure; 1422. Protrusion; 143. Second frame; 1431. Third through hole;

[0047] 15. Cornea; 16. Indentation;

[0048] 21. Top surface; 211. Pressure relief hole; 212. Liquid injection hole; 22. Side surface; 221. First side surface; 222. Second side surface; 23. Bottom surface; 24. Tab. Detailed Implementation

[0049] To make the technical solution and beneficial effects of this utility model more apparent and understandable, a detailed description is provided below by listing specific embodiments. The accompanying drawings are not necessarily drawn to scale, and local features may be enlarged or reduced to more clearly show the details of the local features; unless otherwise defined, the technical and scientific terms used herein have the same meanings as those in the technical field to which this application pertains.

[0050] In the description of this utility model, the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "height", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", and "counterclockwise" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the purpose of simplifying the description of this utility model and do not indicate that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. In other words, they should not be construed as limitations on this utility model.

[0051] In this utility model, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating the relative importance of the indicated features or the number of indicated technical features. Therefore, a feature specified as "first" or "second" can explicitly indicate that at least one of those features is included. In the description of this utility model, "multiple" means at least two, such as two, three, etc.; "several" means at least one, such as one, two, three, etc., unless otherwise explicitly specified.

[0052] In this utility model, unless otherwise explicitly defined, the terms "installation," "connection," "linking," "fixing," and "setting," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral part; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can also refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0053] In this utility model, unless otherwise explicitly defined, the terms "above," "on top of," "above," "over," "below," "below," "below," or "below" for "first feature above second feature" can refer to direct contact between the first and second features, or indirect contact between the first and second features through an intermediate medium. Furthermore, "above," "above," and "over" for "first feature above second feature" can mean the first feature is directly above or diagonally above the second feature, or simply indicates that the horizontal height of the first feature is higher than the horizontal height of the second feature. Similarly, "below," "below," and "below" for "first feature below second feature" can mean the first feature is directly below or diagonally below the second feature, or simply indicates that the horizontal height of the first feature is lower than the horizontal height of the second feature.

[0054] In existing technologies, lithium-ion batteries, as a crucial component of the new energy industry, have insulation structures that directly impact battery safety and reliability. During the production of prismatic batteries, the electrode assembly surface must be wrapped with insulating material to prevent short-circuit risks. Traditional Mylar membranes protect the tabs by creating clearance holes, but the clearance areas lack effective limiting mechanisms, making the tabs prone to displacement, folding, or tearing during welding. Existing insulation structures mostly employ heat-fusion fixing methods, which pose a risk of membrane detachment, and the high-temperature process may damage the internal separator of the battery.

[0055] To address the aforementioned technical problems, this application provides an insulating structure for an electrode assembly. This insulating structure, by placing the frame assembly at the first through-hole of the upper film to avoid the electrode tab, not only restricts the position of the electrode tab and greatly reduces the possibility of the electrode tab folding or tearing, but also ensures effective insulation protection on the upper side of the electrode assembly.

[0056] For details, please refer to Figures 1 to 5 This application provides an insulating structure 1, which includes an upper membrane 11, a side membrane 12, a bottom membrane 13, and a frame assembly 14. The upper membrane 11 is adapted to and covers the top surface 21 of the electrode assembly 100. The upper membrane 11 has a first through hole 111 for avoiding the tab 24. The side membrane 12 extends along a first direction and covers the side surface 22 of the electrode assembly 100. The bottom membrane 13 extends along the first direction and covers the bottom surface 23 of the electrode assembly 100. The frame assembly 14 includes a first frame 141 connected to the upper membrane 11 and an openable door 142. The first frame 141 has a second through hole 1411 corresponding to the first through hole 111. The door 142 is connected to the first frame 141 and presses against the surface of the tab 24 to achieve a limiting position when closed.

[0057] In this embodiment, the upper film 11 is an insulating layer covering the top surface 21 of the electrode assembly 100, and can be formed by die-cutting of polyester film material. The size of the first through hole 111 is slightly larger than the cross-sectional size of the tab 24 to achieve a clearance function. The side film 12 is an insulating structure extending from both sides of the upper film 11, and can be formed by folding to form a covering layer that fits against the side surface 22 of the electrode. The bottom film 13 is a bottom protective layer formed by extending from the end of the side film 12, and its edge can be provided with an adhesive strip to fix the bottom surface 23. The frame assembly 14 refers to a combined structure injection molded from engineering plastic. The first frame 141 is fixed to the surface of the upper film 11 by snap-fit, and the window 142 is opened and closed by hinges or elastic buckles. The first direction is defined as the width direction of the upper film 11, that is, the lateral dimension perpendicular to the extension direction of the tab 24.

[0058] When the insulating structure 1 is assembled to the electrode assembly 100, the upper film 11 covers the top surface 21 and exposes the tab 24 through the first through hole 111. The side film 12 extends downward along the first direction to cover the side surface 22 of the electrode, and the bottom film 13 continues to extend to complete the coverage of the bottom surface 23. The first frame 141 of the frame assembly 14 is fixed to the surface of the upper film 11, and its second through hole 1411 is positioned opposite to the first through hole 111. When the window 142 is closed, its inner surface forms a contact pressure with the upper end face of the tab 24. This pressure is transmitted to the tab 24 through the rigid support of the frame structure, limiting the displacement of the tab 24 in the height direction of the electrode assembly 100. At the same time, the inner wall of the through hole maintains an appropriate gap with the side wall of the tab 24, allowing the tab 24 to deform as necessary while preventing excessive displacement.

[0059] The above insulation structure 1 can greatly reduce the displacement of the tab 24 during welding and other processes, thereby greatly reducing the possibility of the tab 24 folding or tearing. In addition, the mechanical fixing method of the frame assembly 14 can replace the traditional hot-melt process, which can improve the assembly effect and structural reliability, while avoiding the diaphragm shrinkage problem caused by the traditional hot-melt process.

[0060] In an optional embodiment, the side surface 22 includes two first side surfaces 221 disposed opposite to each other along a first direction and two second side surfaces 222 disposed opposite to each other along a second direction. The side membrane 12 includes a first side membrane 121 and a second side membrane 122. The first side membrane 121 extends along the first direction and covers the first side surface 221; the second side membrane 122 extends along the second direction on both sides of the first side membrane 121 and covers the second side surface 222. The second direction is the length direction of the upper membrane 11. A continuous transition structure is formed at the connection between the first side membrane 121 and the second side membrane 122, which can be achieved by an indentation 16 folding process to eliminate the covering gap.

[0061] The side surface 22 of the electrode assembly 100 is divided into coverage areas in different directions. The three-dimensional coverage is achieved through the split side film 12 structure, which enables the side surface 22 of the electrode assembly 100 to be fully covered, thereby improving the support stability of the electrode tab 24 processing area.

[0062] In one alternative embodiment, please refer to Figure 1 The bottom membrane 13 includes a first bottom membrane 132 and a second bottom membrane 133, which are respectively formed by extending from two first side surfaces 221. The first bottom membrane 132 and the second bottom membrane 133 are each provided with a plurality of siphon holes 131, which facilitate the entry of electrolyte into the battery cell. When the insulating structure 1 is assembled onto the electrode assembly 100, the first bottom membrane 132 and the second bottom membrane 133 are stacked, and the siphon holes 131 on the first bottom membrane 132 and the second bottom membrane 133 are staggered to prevent particles from causing abnormal voltage due to connection with the casing.

[0063] In an optional embodiment, a pressure relief hole 211 and / or an injection hole 212 are provided on the top surface 21 of the electrode assembly 100, and one or more fourth through holes 112 are formed at corresponding positions on the upper membrane 11 to avoid the pressure relief hole 211 and / or the injection hole 212. The pressure relief hole 211 is a hole structure provided on the top surface 21 of the electrode assembly 100 for releasing abnormal pressure inside the battery. The injection hole 212 is a channel provided on the top surface 21 of the electrode assembly 100 for injecting electrolyte.

[0064] During the assembly of the insulating structure 1, the upper membrane 11 forms a spatial clearance relationship with the pressure relief hole 211 and the liquid injection hole 212 on the top surface 21 of the electrode assembly 100 through the fourth through hole 112. When the electrolyte is injected, the injection gun can directly pass through the fourth through hole 112 to contact the liquid injection hole 212 to complete the liquid injection operation; when the internal pressure of the battery is abnormal, the pressure relief hole 211 is not covered by insulating material, ensuring that the pressure release path is unobstructed.

[0065] In an optional embodiment, the insulating structure 1 further includes a cornea 15 and an indentation 16. The cornea 15 extends along the second direction on both sides of the upper film 11 and the bottom film 13 to cover the top corner of the electrode assembly 100. The indentation 16 is disposed at the connection between the upper film 11 and the side film 12, and between the side film 12 and the bottom film 13 and corresponds to the corner of the electrode assembly 100. The upper film 11, the side film 12 and the bottom film 13 are integrally formed film materials that are folded and the folding path coincides with the indentation 16.

[0066] Corner membrane 15 extends from both sides of the membrane material, automatically covering the apex corner area of ​​electrode assembly 100 during folding. This eliminates the blind spots at the apex of traditional insulating films, significantly reduces damage caused by impacts, and improves the protection of the electrode assembly 100's corners. Indentations 16 are pre-formed during the membrane material forming stage. During folding, operators can achieve precise alignment between the membranes by bending along the indentation 16 lines. The folded side membrane 12 and bottom membrane 13 naturally form a geometric shape that perfectly fits the corners of the electrode assembly 100. The integrally formed membrane material, guided by the folding path of indentation 16, creates a continuous wrapping structure for the upper membrane 11, side membrane 12, and bottom membrane 13, avoiding the seam gaps that occur during the assembly of traditional separate insulating components.

[0067] In an optional embodiment, the first frame 141 is located on the side of the upper film 11 facing the top surface 21, and the frame assembly 14 further includes a second frame 143. The first frame 141 and the second frame 143 are respectively disposed on both sides of the upper film 11 and clamp and fix the upper film 11.

[0068] In this embodiment, the first frame 141 refers to a rigid support structure disposed on the interface side of the upper membrane 11 and the top surface 21 of the electrode assembly 100. Specifically, it can be implemented using injection-molded engineering plastic parts, with its second through hole 1411 matching the shape of the tab 24 to provide clearance space. The second frame 143 is an auxiliary fixing structure disposed on the side of the upper membrane 11 facing away from the top surface 21 of the electrode assembly 100. Specifically, it can be implemented using a split frame part of the same material as the first frame 141, forming a clamping structure with the first frame 141 through a sleeve or snap-fit ​​method. Clamping and fixing refers to the compression and fixing of the upper membrane 11 between the two frames by the relative pressure of the first frame 141 and the second frame 143 in the vertical direction. Specifically, it can be implemented using an interference fit or an elastic snap-fit ​​structure.

[0069] Specifically, when the first frame 141 and the second frame 143 are located on both sides of the upper membrane 11, they form a closed clamping structure through mechanical connection. During assembly, the upper membrane 11 is placed between the two frames and locked through the sleeve engagement or snap-fit ​​between the frames, generating a clamping force perpendicular to the membrane surface. This clamping force ensures that the upper membrane 11 is tightly attached to the top surface 21 of the electrode assembly 100, while preventing lateral displacement of the upper membrane 11 during the welding of the tab 24 or the assembly of the housing. When the tab 24 is subjected to external force, the first frame 141 limits the base of the tab 24 through the inner wall of the second through hole 1411, while the second frame 143 engages with the first frame 141 through the third through hole 1431, preventing the upper membrane 11 from warping due to stress concentration. The superposition of the double frames and the upper membrane also increases the creepage distance of the tab 24 and improves the insulation effect. This embodiment of the application uses a double-frame clamping structure to achieve bidirectional mechanical constraint of the upper film 11 while maintaining the tab 24's avoidance function, thereby improving the positioning accuracy and packaging reliability of the tab 24.

[0070] In an optional embodiment, the second frame 143 has a third through hole 1431. The first frame 141 and the second frame 143 are fitted together by the inner wall of the third through hole 1431 abutting against the outer wall of the first frame 141, or by the inner wall of the second through hole 1411 abutting against the outer wall of the second frame 143. The second through hole 1411 and the third through hole 1431 are through holes formed on the first frame 141 and the second frame 143, respectively.

[0071] In this embodiment, in the sleeve connection between the third through hole 1431 and the first frame 141, the second frame 143 is pre-machined with a third through hole 1431 whose inner diameter is slightly smaller than the outer diameter of the first frame 141. During assembly, the first frame 141 is pressed into the third through hole 1431, and elastic deformation generates a uniform circumferential contact pressure, thereby forming a fixed connection without relative displacement. In the sleeve connection between the second through hole 1411 and the second frame 143, the outer diameter of the second frame 143 is designed to be slightly larger than the inner diameter of the second through hole 1411. During assembly, the second frame 143 is inserted into the second through hole 1411, and a tight fit is achieved through radial compression. Both methods replace traditional fasteners with physical interference, simplifying the assembly steps while ensuring connection strength.

[0072] The shapes of the third through hole 1431, the second through hole 1411 and the first through hole 111 in this embodiment are not specifically limited in this embodiment, and can be circular holes, elliptical holes, square holes, etc.

[0073] In an optional embodiment, the first frame 141 is provided with a first snap-fit ​​structure 1412, and the window 142 is provided with a second snap-fit ​​structure 1421 adapted to the first snap-fit ​​structure 1412. The window 142 is closed and locked to the first frame 141 by the snap-fit ​​of the first snap-fit ​​structure 1412 and the second snap-fit ​​structure 1421.

[0074] In this embodiment, the first latching structure 1412 refers to a mechanical locking unit disposed on the edge of the frame, which can be implemented using a groove 1413 or a slot structure. Its depth and width are designed according to the force requirements when the window / door 142 is closed, to provide a stable latching space. The second latching structure 1421 refers to a movable part that complements the first latching structure 1412, which can be implemented using a protrusion 1422 or a tongue structure. Its size matches the first latching structure 1412, and it is embedded in the groove 1413 to form a physical limit when closed.

[0075] This application embodiment solves the problem of the electrode lug 24 shifting or loosening due to the window / door 142 failing to lock securely after closing. The mechanical locking force generated by the snap-fit ​​structure ensures that the window / door 142 remains closed during welding, preventing the electrode lug 24 from shifting due to vibration. Simultaneously, this structure eliminates the need for auxiliary fixing components, simplifying the assembly process and reducing the risk of insulation failure caused by improper tightening.

[0076] In an optional embodiment, the first latching structure 1412 includes a groove 1413 provided in the first frame 141, and the second latching structure 1421 includes a protrusion 1422 provided on the side of the window 142 near the first frame 141. The protrusion 1422 is inserted into the groove 1413 so that the window 142 is locked to the first frame 141.

[0077] In this embodiment, when the window 142 closes towards the first frame 141, the protrusion 1422 slides into the inclined surface of the groove 1413 opening. The elastic deformation generated by the interference fit causes the protrusion 1422 to be engaged at the bottom of the groove 1413. The inner wall of the groove 1413 forms a circumferential enclosure around the protrusion 1422. In the vertical direction, the contact between the bottom surface 23 of the groove 1413 and the top surface 21 of the protrusion 1422 prevents the window 142 from lifting. In the horizontal direction, the contact between the side wall of the groove 1413 and the side surface 22 of the protrusion 1422 restricts lateral displacement. In the closed state, the contact surface pressure between the protrusion 1422 and the groove 1413 generates static friction, which, combined with the mechanical limit, forms a self-locking effect. This embodiment enables the window 142 to stably press against the surface of the electrode tab 24 in the closed state, greatly reducing the possibility of the electrode tab 24 folding or tearing during welding.

[0078] In one alternative embodiment, please refer to Figure 6 and Figure 7When the electrode assembly 100 is a single-electrode group, the window 142 is connected to the frame of the first frame 141 along the second direction. When the electrode assembly 100 is a multi-electrode group, please refer to... Figure 2 The window 142 is connected to the frame of the first frame 141 along the first direction; wherein, the second direction is the length direction of the upper membrane 11.

[0079] Among them, a single-stage group is an electrode assembly 100 containing only a single positive and negative tab 24 structure, while a multi-stage group is an electrode assembly 100 containing multiple parallel or series tab 24 structures, which can be implemented by an array of multiple tabs 24 arranged along the width direction. The multi-stage group can be a bipolar group cell or a quadruple group cell.

[0080] This application embodiment can automatically match the optimal closing direction of the window 142 according to the distribution characteristics of the tabs 24 of the electrode assembly 100. In the application of a single electrode group, it forms a lateral constraint to prevent the tabs 24 from shifting laterally. In the scenario of a multi-electrode group, it achieves uniform pressure distribution to avoid local stress concentration. This eliminates the risk of misalignment, folding or tearing caused by the mismatch between the closing direction of the window 142 and the layout of the tabs 24 during the welding process, and improves the positioning stability and processing reliability of the tabs 24.

[0081] This application also provides a battery cell, which includes an electrode assembly, an insulating structure 1 provided in any of the above embodiments, and a housing.

[0082] The electrode assembly 100 has a top surface 21, a side surface 22, and a bottom surface 23, with a tab 24 on the top surface 21. The housing has an open-end receiving space, within which the electrode assembly 100 and the insulating structure 1 are disposed. The upper film 11, the side film 12, and the bottom film 13 respectively cover the top surface 21, the side surface 22, and the bottom surface 23. The first frame 141 is connected to the upper film 11, and the window 142 is openable and closable and connected to the first frame 141, pressing against the surface of the tab 24 when closed.

[0083] The electrode assembly 100 is completely covered by the upper film 11, side film 12, and bottom film 13, forming a multi-layered insulating protection. When the upper film 11 covers the top surface 21, its first through hole 111 avoids the tab 24, and the first frame 141 is aligned with the tab 24 and fixed to the upper film 11 through the second through hole 1411. After the window 142 is closed, its inner surface contacts the tab 24 and applies pressure, confining the tab 24 within the area of ​​the first through hole 111. The side film 12 and the bottom film 13 form a three-dimensional covering structure by folding, covering the side surface 22 and bottom surface 23 of the electrode assembly 100 to prevent short circuits from contacting the housing. The housing constrains the position of the electrode assembly 100 and the insulating structure 1 by accommodating the space, ensuring that the tab 24 maintains an insulating gap with the housing. In this embodiment, the closable structure of the window 142 and the first frame 141 actively presses against the surface of the tab 24 when closed, forming a mechanical limit and preventing the tab 24 from being misaligned. Meanwhile, the integrated wrapping design of the upper membrane 11, side membrane 12 and bottom membrane 13 eliminates the weak points of insulation at the joints compared with the separate insulation structure 1.

[0084] The aforementioned battery cells prevent the tabs 24 from becoming misaligned, folded, or torn during the packaging process due to lack of fixation. The mechanical pressure of the closed window 142 directly constrains the displacement of the tabs 24, avoiding positional deviations during the welding process. The full-surface coverage of the multi-layer film material blocks the conductive contact between the electrode assembly 100 and the housing, preventing the risk of short circuits. The design of the frame and film material achieves the positioning of the tabs 24 while maintaining the integrity of the insulation structure 1 and assembly efficiency.

[0085] It should be understood that the above embodiments are exemplary and are not intended to encompass all possible implementations included in the claims. Various modifications and changes can be made to the above embodiments without departing from the scope of this disclosure. Similarly, the various technical features of the above embodiments can be arbitrarily combined to form other embodiments of this application that may not be explicitly described. Therefore, the above embodiments only illustrate several implementations of this application and do not limit the scope of protection of this patent application.

Claims

1. An insulating structure, characterized in that, For an electrode assembly (100), the electrode assembly (100) has a top surface (21), a side surface (22) and a bottom surface (23), the top surface (21) being provided with tabs (24); the insulating structure (1) includes: The upper membrane (11) is adapted to and covers the top surface (21), and the upper membrane (11) has a first through hole (111) for avoiding the tab (24). Side film (12) extends along the first direction on both sides of the upper film (11) and is adapted to the side surface (22) for covering the side surface (22). A bottom film (13) extends along the first direction at the end of the side film (12) and is adapted to the bottom surface (23) for covering the bottom surface (23). The frame assembly (14) includes a first frame (141) and a window (142). The first frame (141) is connected to the upper membrane (11) and has a second through hole (1411) adapted to the first through hole (111). The window (142) is openable and closable and connected to the first frame (141). In the closed state, it presses against the surface of the electrode (24) to confine the electrode (24) within the first through hole (111). The first direction is the width direction of the upper membrane (11).

2. The insulation structure according to claim 1, characterized in that, The first frame (141) is located on the side of the upper membrane (11) facing the top surface (21); The frame assembly (14) also includes: The second frame (143) is provided on both sides of the upper film (11) and the first frame (141) are respectively disposed and clamp the upper film (11) in place.

3. The insulation structure according to claim 2, characterized in that, The second frame (143) has a third through hole (1431). The first frame (141) and the second frame (143) are fitted together by the inner wall of the third through hole (1431) abutting against the outer wall of the first frame (141); or the fitted together is achieved by the inner wall of the second through hole (1411) abutting against the outer wall of the second frame (143).

4. The insulation structure according to claim 3, characterized in that, The first frame (141) is provided with a first buckle structure (1412), and the window (142) is provided with a second buckle structure (1421) adapted to the first buckle structure (1412). The window (142) is closed and locked to the first frame (141) by the buckling of the first buckle structure (1412) and the second buckle structure (1421).

5. The insulation structure according to claim 4, characterized in that, The first latching structure (1412) includes a groove (1413) provided in the first frame (141), and the second latching structure (1421) includes a protrusion (1422) provided on the side of the window (142) near the first frame (141). The protrusion (1422) is inserted into the groove (1413) so that the window (142) is locked to the first frame (141).

6. The insulating structure according to any one of claims 1 to 5, characterized in that, The side surface (22) includes two first side surfaces (221) disposed opposite each other along the first direction and two second side surfaces (222) disposed opposite each other along the second direction; the side membrane (12) includes: The first side membrane (12) extends along the first direction and covers the first side surface (221). The second side membrane (12) extends along the second direction on both sides of the first side membrane (12) and covers the second side surface (222), the second direction being the length direction of the upper membrane (11).

7. The insulating structure according to any one of claims 1 to 5, characterized in that, The top surface (21) is provided with a pressure relief hole (211) and / or a liquid injection hole (212); the upper membrane (11) is provided with at least one fourth through hole (112) to avoid the pressure relief hole (211) and / or the liquid injection hole (212).

8. The insulating structure according to any one of claims 1 to 5, characterized in that, The insulating structure (1) further includes: The cornea (15) extends along a second direction on both sides of the upper membrane (11) and the bottom membrane (13) to cover the apex of the electrode assembly (100), the second direction being the length direction of the upper membrane (11); Indentations (16) are provided at the connection between the upper film (11) and the side film (12) and at the connection between the side film (12) and the bottom film (13), corresponding to the corners of the electrode assembly (100); The upper membrane (11), the side membrane (12) and the bottom membrane (13) are integrally formed membrane materials that are folded, and the folding path coincides with the indentation (16).

9. The insulating structure according to any one of claims 1 to 5, characterized in that, When the electrode assembly (100) is a single electrode group, the window (142) is connected to the frame of the first frame (141) along the second direction; When the electrode assembly (100) is a multi-electrode group, the window (142) is connected to the frame of the first frame (141) along the first direction; wherein, the second direction is the length direction of the upper film (11).

10. A single battery cell, characterized in that, include: The electrode assembly has a top surface (21), a side surface (22) and a bottom surface (23), wherein the top surface (21) is provided with a tab (24); The insulation structure according to any one of claims 1 to 9; The housing has an accommodating space with an opening at one end, and the electrode assembly and the insulating structure are disposed within the accommodating space; The upper membrane (11), the side membrane (12) and the bottom membrane (13) respectively cover the top surface (21), the side surface (22) and the bottom surface (23), the first frame (141) is connected to the upper membrane (11), the window (142) is openable and closed and connected to the first frame (141), and presses against the surface of the tab (24) in the closed state.

Images