Winded cells and batteries

Abstract

This application provides a wound cell and a battery. The wound cell includes: a winding body, including: a first electrode, a second electrode, and a separator separating the first electrode and the second electrode, wherein the winding body is wound to form a wound cell; and a support member, disposed between two arc-shaped areas of the innermost ring of the wound cell, for limiting relative displacement between the arc-shaped areas of the wound cell.

Description

Technical Field

[0001] This application relates to the field of battery cell technology, and in particular to a wound battery cell and battery. Background Technology

[0002] During the winding process of bare battery cells, such as Figure 1 As shown, the current method involves winding the first electrode 11, the second electrode (i.e., the anode and cathode electrodes), and the separator 13 onto a winding needle while setting a certain winding tension. After winding, the winding needle is pulled out to form a bare cell. When the winding needle is pulled out in this way, the internal binding force is released, which easily causes the inner separator to fold. At the same time, the anode and cathode shrink inward, resulting in an increase in the gap at the corner of the bare cell, which worsens the dynamics and leads to purple or black spots at the corners, thus causing problems with battery cycle life and expansion. Utility Model Content

[0003] The purpose of this application is to provide a wound-type battery cell and battery.

[0004] To address the aforementioned technical problems, this application provides the following technical solutions:

[0005] The first aspect of this application provides a wound battery cell, comprising:

[0006] The winding body includes: a first electrode, a second electrode, and a separator separating the first electrode and the second electrode, wherein the winding body is formed into the wound battery cell by winding.

[0007] A support member is disposed between the two arc-shaped areas of the innermost ring of the wound battery cell to limit relative displacement between the arc-shaped areas of the wound battery cell.

[0008] In some embodiments, the wound body is wound to form alternating planar regions and arc-shaped regions, the planar regions being stacked along the thickness direction of the wound cell, and the arc-shaped regions being connected to two adjacent layers of the planar regions;

[0009] The support member is a structural component made of insulating material, and the length and / or width of the support member is at least the same as the length and / or width of the innermost planar region.

[0010] In some embodiments, the first end of the winding body is a winding start section, and the support member is fixed to the mounting section of the winding body adjacent to the winding start section.

[0011] In some embodiments, the support is bonded to the surface of the diaphragm, and the edge of the support has a smooth region.

[0012] In some embodiments, the support member has a preset deformability to conform to the corresponding surface of the winding needle during the winding process of the winding body;

[0013] And / or,

[0014] The thickness of the support is 2μm-5μm.

[0015] In some embodiments, the support member is configured to be movably connected to the winding needle, and the support member is capable of separating from the winding needle after the winding body is wound and remaining in the innermost ring of the wound cell.

[0016] In some embodiments, the wound body is wound to form alternating first sub-arc regions and second sub-arc regions, the first sub-arc regions being stacked along the thickness direction of the wound cell, and the second sub-arc regions being connected to two adjacent layers of the first sub-arc regions;

[0017] The first sub-arc region and the second sub-arc region have different radii of curvature.

[0018] In some embodiments, the extension direction of the support member is the same as the length direction of the winding body, and at least one support member is provided in the width direction of the winding body.

[0019] In some embodiments, one of the support members is located at the center of the width direction of the winding body.

[0020] A second aspect of this application provides a battery, comprising:

[0021] A wound battery cell and a battery management system chip, wherein the battery management system chip is used to manage and control the operating parameters of the wound battery cell;

[0022] The wound battery cell includes:

[0023] The winding body includes: a first electrode, a second electrode, and a separator separating the first electrode and the second electrode, wherein the winding body is formed into the wound battery cell by winding.

[0024] A support member is disposed between the two arc-shaped areas of the innermost ring of the wound battery cell to limit relative displacement between the arc-shaped areas of the wound battery cell. Attached Figure Description

[0025] The above and other objects, features, and advantages of exemplary embodiments of this application will become readily understood by reading the following detailed description with reference to the accompanying drawings. In the drawings, several embodiments of this application are illustrated by way of example and not limitation, with the same or corresponding reference numerals denoteing the same or corresponding parts, wherein:

[0026] Figure 1 A schematic diagram of the structure of a bare battery cell in the prior art is shown.

[0027] Figure 2 A schematic diagram of the structure of the wound battery cell of this application is shown.

[0028] Explanation of icon numbers:

[0029] 1. Winding body; 11. First electrode; 12. Second electrode; 13. Diaphragm; 14. Planar region; 15. Arc-shaped region; 2. Support component. Detailed Implementation

[0030] The embodiments of this disclosure will be further described in detail below with reference to the accompanying drawings and examples. The detailed description of the embodiments and the accompanying drawings are used to illustrate the principles of this disclosure by way of example, but should not be used to limit the scope of this disclosure. This disclosure can be implemented in many different forms and is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

[0031] These embodiments are provided to make the disclosure thorough and complete, and to fully express the scope of the disclosure to those skilled in the art. It should be noted that, unless otherwise specifically stated, the relative arrangement of components and steps, material composition, numerical expressions, and values ​​set forth in these embodiments should be interpreted as exemplary only and not as limiting.

[0032] It should be noted that, in the description of this disclosure, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," and "outer," etc., indicating orientation or positional relationship, are only for the convenience of describing this disclosure 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 disclosure. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0033] Furthermore, the terms "first," "second," and similar terms used in this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish different parts. "Vertical" is not strictly vertical, but within the permissible margin of error. "Parallel" is not strictly parallel, but within the permissible margin of error. Terms such as "including" or "contains" mean that the element preceding the word encompasses the element listed after the word, and do not exclude the possibility of encompassing other elements as well.

[0034] It should also be noted that, in the description of this disclosure, unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this disclosure depending on the specific circumstances. When a particular device is described as being located between a first device and a second device, an intermediary device may or may not be present between the particular device and the first or second device.

[0035] All terms used in this disclosure have the same meaning as understood by one of ordinary skill in the art to which this disclosure pertains, unless otherwise specifically defined. It should also be understood that terms defined in general dictionaries should be interpreted as having meanings consistent with their meanings in the context of the relevant art, and not as idealized or highly formalized, unless expressly defined herein.

[0036] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, they should be considered part of the specification.

[0037] Example 1

[0038] like Figure 2 As shown, Embodiment 1 of this application provides a wound battery cell, comprising:

[0039] The winding body 1 includes: a first electrode 11, a second electrode 12, and a separator 13 that separates the first electrode 11 and the second electrode 12. The winding body 1 is formed into the wound battery cell by winding.

[0040] The support member 2 is disposed between the two arc-shaped areas 15 of the innermost ring of the wound battery cell, and is used to limit the relative displacement between the arc-shaped areas 15 of the wound battery cell.

[0041] The wound body 1 is used to realize energy storage and conversion. The wound body 1 can include multiple electrode pairs (each electrode pair includes a first electrode 11 and a second electrode 12), and the specific number can be designed according to the size and capacity of the battery. In the manufacturing process, a separator 13, a first electrode 11, another separator 13, and a second electrode 12 can be stacked sequentially and repeated multiple times to form a multi-layer structure. Then, a winding needle is used as an auxiliary tool to wind the multi-layer structure into a flat wound cell. The first electrode 11 can be the anode, and the second electrode 12 can be the cathode, or vice versa. Graphite or silicon-carbon composite materials can be used as anode materials, and lithium nickel manganese cobalt oxide or lithium iron phosphate can be used as cathode materials. The separator 13 can be made of polyethylene or polypropylene material with good ionic conductivity and mechanical strength.

[0042] The anode and cathode materials undergo electrochemical reactions to store and release electrical energy. When the battery is charging, lithium ions are deintercalated from the positive electrode and migrate through the electrolyte to the negative electrode, where they are intercalated; the reverse occurs during discharge. This process enables the battery to store and provide electrical energy. The separator 13, located between the anode and cathode, acts as a physical barrier, preventing electrons from directly passing through and causing an internal short circuit. Simultaneously, the separator 13 allows lithium ions to move freely within it, ensuring the normal operation of the battery.

[0043] The support member 2 provides physical support to prevent relative displacement between the arc-shaped areas 15 of the wound cell after the winding needle is withdrawn. Specifically, the support member 2 restricts relative displacement between the two oppositely arranged arc-shaped areas 15 of the innermost ring of the wound cell; it also restricts relative displacement between the two oppositely arranged arc-shaped areas 15 of other inner rings of the wound cell; and it restricts displacement between multiple arc-shaped areas 15 on the same side of the wound cell. This prevents the separator 13 from folding and the anode and cathode from shrinking due to the release of internal binding forces after the winding needle is withdrawn, thus improving the overall stability and safety of the battery. The support member 2 can be bonded to the first end of the wound cell, for example, using hot melt adhesive or UV-cured adhesive.

[0044] The wound battery cell provided in Embodiment 1 of this application is formed by winding a winding body 1. The first electrode and the second electrode undergo electrochemical reactions to achieve the storage and release of electrical energy. The separator 13 is located between the anode and cathode, serving as a physical barrier to ensure that electrons cannot pass directly and cause internal short circuits. At the same time, the separator 13 allows lithium ions to move freely within it, ensuring the normal operation of the battery. The support member 2 is disposed between the two arc-shaped areas 15 of the innermost ring of the wound battery cell. After the wound battery cell is wound and the winding needle is removed, it can provide physical support, effectively limiting the relative displacement between the arc-shaped areas 15, preventing structural loosening due to the release of internal binding forces, avoiding wrinkles in the separator 13 and inward shrinkage of the anode and cathode sheets, ensuring good contact and tight connection at the corners of the bare battery cell, maintaining the dynamic performance of the battery cell, reducing deformation problems caused by expansion or contraction, extending its service life and improving safety.

[0045] like Figure 2 As shown, in some embodiments, the wound body 1 is wound to form alternating planar regions 14 and arc-shaped regions 15. The planar regions 14 are stacked along the thickness direction of the wound cell, and the arc-shaped regions 15 are connected to two adjacent layers of the planar regions 14.

[0046] The support member 2 is a structural member made of insulating material, and the length and / or width of the support member 2 are at least the same as the length and / or width of the innermost planar region 14.

[0047] The support member 2 can be flat. The support member 2 can be made of insulating materials such as polyethylene terephthalate or glass fiber reinforced plastic to ensure sufficient mechanical strength without affecting the electrical performance of the battery. The length of the support member 2 can be the same as the length of the innermost planar region 14; or, the width of the support member 2 can be the same as the width of the innermost planar region 14; or, to ensure that the support member 2 can effectively provide physical support, the length of the support member 2 is the same as the length of the innermost planar region 14, and the width of the support member 2 is the same as the width of the innermost planar region 14. The sides of the support member 2 along its width direction can be curved surfaces with a certain degree of curvature to better fit the inner ring structure of the winding body 1 and reduce stress concentration problems caused during the winding process.

[0048] The alternating planar region 14 and arc-shaped region 15 of the wound body 1 effectively disperse stress, reducing internal stress concentration caused by bending during the winding process, enhancing the overall mechanical strength of the wound cell, and preventing deformation due to external pressure or its own expansion. The planar region 14 is stacked along the thickness direction, allowing the cell to achieve higher energy density within a limited space, improving space utilization efficiency. The insulating support member 2 effectively avoids short-circuit risks while providing necessary physical support, thereby enhancing the safety and reliability of the wound cell.

[0049] like Figure 2 As shown, in some embodiments, the first end of the winding body 1 is a winding start section, and the support member 2 is fixed to the mounting section of the winding body 1 adjacent to the winding start section.

[0050] The support member 2 and the first end face of the wound body 1 have a preset distance. This preset distance can be obtained by simulating and analyzing the stress distribution under different distances using engineering software, or by actual testing. The winding start section is one of the stress concentration areas. The installation section is adjacent to the winding start section. That is, the support member 2 is adjacent to or spaced apart from the winding start section, which allows the wound body 1 to naturally adapt to bending, reducing the potential risk of damage, thereby improving the mechanical strength and durability of the entire wound cell.

[0051] like Figure 2 As shown, in some embodiments, the support member 2 is bonded to the surface of the diaphragm 13, and the edge of the support member 2 has a smooth area.

[0052] The edges of the support member 2 can be processed using precision machining methods such as grinding and polishing to achieve the required smoothness. Alternatively, chemical etching or polishing fluid treatment can be used to smooth the edges of the support member 2; or, laser cutting or sintering techniques can be used to form smooth edges during the manufacturing process.

[0053] The edges of the support member 2 are smoothed, which can significantly reduce the coefficient of friction with the innermost ring. This allows it to adapt well to the expansion and contraction of the battery interior due to temperature changes and charge-discharge cycles, reducing damage caused by friction. At the same time, it can also ensure the integrity of the separator 13, prevent short circuit risks, and improve battery safety.

[0054] like Figure 2 As shown, in some embodiments, the support member 2 has a preset deformability, which is used to conform to the corresponding surface of the winding needle during the winding process of the winding body 1.

[0055] And / or,

[0056] The thickness of the support is 2μm-5μm.

[0057] The support component 2 can be made of thermoplastic, rubber, or other elastic materials; alternatively, it can be a composite material containing reinforcing fibers (such as glass fiber or carbon fiber) and a matrix material (such as polyethylene or polypropylene) to provide the required strength and deformation capacity. The support component 2 with the preset deformation capacity can be manufactured using molding processes such as injection molding and calendering. The molded support component 2 can be heat-treated to adjust its internal microstructure and optimize its deformation capacity and recovery performance. The thickness of the support component can be 2μm, 3μm, 4μm, or 5μm, etc.

[0058] The pre-designed deformability of the support component 2 allows it to fit tightly against the surface of the winding needle during the winding process, ensuring that each layer of material is wound evenly and tightly, reducing gaps and misalignments, thereby improving winding quality and the consistency of the wound cell. During the winding process, the support component 2 can flexibly adjust its shape according to changes in the surface of the winding needle, effectively dispersing the stress applied to the wound body 1, avoiding damage or failure caused by local stress concentration, while maintaining the shape stability of the entire wound body 1, preventing deformation caused by external pressure or its own expansion, and extending battery life.

[0059] like Figure 2 As shown, in some embodiments, the support member 2 is used to be movably connected with the winding needle, and the support member 2 can be separated from the winding needle after the winding body 1 is wound into shape, and remain in the innermost ring of the wound cell.

[0060] The support member 2 and the winding needle can be magnetically connected. For example, a small permanent magnet can be embedded inside the support member 2, and a layer of magnetic material can be coated on the surface of the winding needle to achieve magnetic attraction between the two, while allowing them to be disengaged when an external force is applied. Alternatively,

[0061] The winding needle can have multiple channels inside, with the first end of each channel extending to the surface of the needle to form multiple pores. These pores are evenly distributed to provide uniform suction force. The second end of each channel can be connected to an external pneumatic system. During operation, the support 2 is placed on the surface of the winding needle, the pneumatic system is activated, and a vacuum is created through the pores, forming a negative pressure environment between the winding needle and the flat back of the support 2. This allows the support 2 to firmly adhere to the winding needle, ensuring a secure and reliable connection. Then, the winding process begins. Once winding is complete and the wound body 1 reaches the required size, the pneumatic system is turned off or switched to positive pressure mode to release the suction between the support 2 and the winding needle. The support 2 remains within the wound body 1 as the innermost loop, while the winding needle can be easily pulled out for the next winding cycle. The support 2, used for the movable connection with the winding needle, lays the foundation for automated production, thereby significantly improving the overall efficiency of the production line.

[0062] like Figure 2 As shown, in some embodiments, the wound body 1 is wound to form alternating first sub-arc regions and second sub-arc regions (not shown in the figure), the first sub-arc regions are stacked along the thickness direction of the wound cell, and the second sub-arc regions are connected to the two adjacent layers of the first sub-arc regions.

[0063] The first sub-arc region and the second sub-arc region have different radii of curvature.

[0064] The support member 2 can be elliptical, in which case the wound body 1 can be elliptical or rugby ball-shaped after winding. The radius of curvature of the first sub-arc region can be larger than that of the second sub-arc region, so that the first sub-arc region provides sufficient support and distributes stress, while the second sub-arc region adapts to a more compact spatial layout. The radii of curvature of the first and second sub-arc regions can be flexibly adjusted according to different application requirements. For example, a larger radius of curvature is suitable for areas requiring higher mechanical strength and stability, while a smaller radius of curvature is suitable for compact designs requiring higher energy density.

[0065] By alternately setting the first and second sub-arc regions with different radii of curvature, stress can be evenly distributed within the winding body 1, reducing the risk of material fatigue or damage caused by local stress concentration, and ensuring mechanical strength while taking into account flexibility and adaptability.

[0066] like Figure 2 As shown, in some embodiments, the extension direction of the support member 2 is the same as the length direction of the winding body 1, and at least one support member 2 is provided in the width direction of the winding body 1.

[0067] like Figure 2 As shown, in some embodiments, one of the support members 2 is located at the center position in the width direction of the winding body 1.

[0068] When only one support member 2 is used, it can be positioned at the center of the winding body 1 in the width direction to ensure uniform support throughout the winding process. For applications requiring higher strength or more uniform support, multiple support members 2 can be used in the width direction of the winding body 1; for example, two, three, four, or more. These multiple support members 2 can be arranged at equal intervals along the width direction of the winding body 1 to ensure that each section receives the same support force. Alternatively, the spacing between the multiple support members 2 can be adjusted according to the actual stress distribution requirements. For example, when stress concentration is high in certain areas, the number of support members 2 can be increased or the spacing between them can be shortened in these areas.

[0069] The number and arrangement of support components 2 can be flexibly adjusted according to the needs of different application scenarios. For example, in high-vibration environments, the number of support components 2 can be increased to enhance vibration resistance; under high energy density requirements, a more compact design can be adopted to adapt to diverse application scenarios and improve safety.

[0070] Example 2

[0071] Embodiment 2 of this application provides a battery, comprising:

[0072] A wound battery cell and a battery management system chip, wherein the battery management system chip is used to manage and control the operating parameters of the wound battery cell;

[0073] like Figure 2 As shown, the wound battery cell includes:

[0074] The winding body 1 includes: a first electrode 11, a second electrode 12, and a separator 13 that separates the first electrode 11 and the second electrode 12. The winding body 1 is formed into the wound battery cell by winding.

[0075] The support member 2 is disposed between the two arc-shaped areas 15 of the innermost ring of the wound battery cell, and is used to limit the relative displacement between the arc-shaped areas 15 of the wound battery cell.

[0076] The battery can be a lithium-ion battery or a nickel-metal hydride battery, etc. Operating parameters can include voltage, current, temperature, state of charge, health status, etc.

[0077] The battery provided in Embodiment 2 of this application includes the wound cell of Embodiment 1. The wound cell is formed by winding a winding body 1. The first electrode and the second electrode undergo electrochemical reactions to achieve energy storage and release. A separator 13 is located between the anode and cathode, providing physical isolation to prevent electrons from directly passing through and causing internal short circuits. Simultaneously, the separator 13 allows lithium ions to move freely within it, ensuring normal battery operation. A support member 2 is disposed between the two arc-shaped areas 15 of the innermost ring of the wound cell. After the wound cell is wound and the winding needle is removed, it provides physical support, effectively limiting the relative displacement between the arc-shaped areas 15, preventing structural loosening due to the release of internal binding forces, avoiding wrinkles in the separator 13 and inward shrinkage of the anode and cathode plates, ensuring good contact and tight connection at the corners of the bare cell, maintaining the cell's dynamic performance, reducing deformation due to expansion or contraction, extending its service life, and improving safety, thereby enhancing battery safety.

[0078] The embodiments of this disclosure have now been described in detail. To avoid obscuring the concept of this disclosure, some details known in the art have not been described. Those skilled in the art can fully understand how to implement the technical solutions disclosed herein based on the above description.

[0079] While specific embodiments of this disclosure have been described in detail by way of examples, those skilled in the art should understand that the examples are for illustrative purposes only and not intended to limit the scope of this disclosure. Those skilled in the art should understand that modifications can be made to the above embodiments or equivalent substitutions can be made to some technical features without departing from the scope and spirit of this disclosure. In particular, as long as there is no structural conflict, the technical features mentioned in the various embodiments can be combined in any manner.

Claims

1. A wound battery cell, characterized in that, include: The winding body includes: a first electrode, a second electrode, and a separator separating the first electrode and the second electrode, wherein the winding body is formed into the wound battery cell by winding. A support member is disposed between the two arc-shaped areas of the innermost ring of the wound battery cell to limit relative displacement between the arc-shaped areas of the wound battery cell.

2. The wound battery cell according to claim 1, characterized in that, The wound body is wound to form alternating planar areas and arc-shaped areas. The planar areas are stacked along the thickness direction of the wound cell, and the arc-shaped areas are connected to the two adjacent planar areas. The support member is a structural component made of insulating material, and the length and / or width of the support member is at least the same as the length and / or width of the innermost planar region.

3. The wound battery cell according to claim 2, characterized in that, The first end of the winding body is the winding start section, and the support member is fixed to the mounting section of the winding body adjacent to the winding start section.

4. The wound battery cell according to claim 3, characterized in that, The support is bonded to the surface of the diaphragm, and the edge of the support has a smooth area.

5. The wound battery cell according to claim 3 or 4, characterized in that, The support member has a preset deformability and is used to conform to the corresponding surface of the winding needle during the winding process of the winding body; And / or, The thickness of the support is 2μm-5μm.

6. The wound battery cell according to claim 2, characterized in that, The support member is used to be movably connected with the winding needle. The support member can be separated from the winding needle after the winding body is wound and remains in the innermost ring of the wound cell.

7. The wound battery cell according to claim 1, characterized in that, The wound body is wound to form alternating first sub-arc regions and second sub-arc regions. The first sub-arc regions are stacked along the thickness direction of the wound cell, and the second sub-arc regions are connected to the two adjacent layers of the first sub-arc regions. The first sub-arc region and the second sub-arc region have different radii of curvature.

8. The wound battery cell according to claim 2, characterized in that, The extension direction of the support member is the same as the length direction of the winding body, and at least one of the support members is provided in the width direction of the winding body.

9. The wound battery cell according to claim 8, characterized in that, One of the support members is located at the center of the width direction of the winding body.

10. A battery, characterized in that, include: A wound battery cell and a battery management system chip, wherein the battery management system chip is used to manage and control the operating parameters of the wound battery cell; The wound battery cell includes: The winding body includes: a first electrode, a second electrode, and a separator separating the first electrode and the second electrode, wherein the winding body is formed into the wound battery cell by winding. A support member is disposed between the two arc-shaped areas of the innermost ring of the wound battery cell to limit relative displacement between the arc-shaped areas of the wound battery cell.

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