Lithium ion battery and electric device
By setting a coating between the lithium-ion battery core and the aluminum-plastic film, the problem of insufficient heat dissipation in lithium-ion batteries is solved, achieving better heat dissipation and improved battery performance while maintaining the same energy density.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-17
- Publication Date
- 2026-03-03
AI Technical Summary
Existing lithium-ion batteries have insufficient heat dissipation capacity during charging and discharging, resulting in increased temperature, which affects battery life and charging/discharging capacity. At the same time, increasing the current collector thickness will reduce energy density.
A coating is placed between the core of the lithium-ion battery and the aluminum-plastic film. The coating material has solid heat transfer properties or a microporous structure to promote heat dissipation or absorb heat and enhance heat dissipation capacity without changing the thickness of the current collector.
It effectively reduces the temperature rise of lithium-ion batteries during charging and discharging, improves battery charging and discharging capabilities and lifespan, while maintaining the same energy density.
Smart Images
Figure CN223967246U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of new energy technology, and in particular to lithium-ion batteries and electrical devices. Background Technology
[0002] With the widespread application of lithium-ion batteries, increasingly higher requirements are being placed on their charge and discharge capabilities to enhance product competitiveness. Higher charge / discharge rates lead to higher battery temperature rises, which to some extent limits the improvement of charge and discharge capabilities and affects battery lifespan. The temperature rise of lithium-ion batteries is affected by two factors: the amount of heat generated by the battery itself and the rate at which the battery dissipates heat.
[0003] In related technologies, heat dissipation solutions for lithium-ion batteries include increasing the thickness of the current collector. However, increasing the thickness of the current collector reduces the battery's energy density (ED). Therefore, how to enhance the heat dissipation capacity of lithium-ion batteries and reduce their temperature rise without affecting the battery's ED has become an urgent problem to be solved. Utility Model Content
[0004] To address or partially address the problems existing in related technologies, this application provides a lithium-ion battery and an electrical device that can enhance the heat dissipation capacity of the lithium-ion battery, reduce the temperature rise during charging and discharging, and at the same time, not affect the energy density of the lithium-ion battery.
[0005] The first aspect of this application provides a lithium-ion battery, comprising:
[0006] The core and the aluminum-plastic film covering the core;
[0007] There is a gap between the core and the aluminum-plastic film. The side of the core corresponding to the gap is coated with a coating of a specified material. The coating is used to promote heat dissipation or absorb heat from the side of the core.
[0008] In one implementation, the coating material is a material with solid-solid heat transfer properties.
[0009] In one implementation, the material with solid-solid heat transfer properties is at least one of polypropylene, polycarbonate, nylon, or polyimide.
[0010] In one implementation, the coating material is a material with solid-gas heat transfer properties; or,
[0011] The coating material is a material with a microporous structure.
[0012] In one implementation, the material with solid-gas heat transfer properties or the material with a microporous structure is at least one of porous ceramics, porous carbon materials, or nanomaterials.
[0013] In one implementation, the material of the coating has a specific heat capacity higher than a set value; or,
[0014] The coating material is at least one of ceramic, paraffin, or modified polymer materials.
[0015] In one implementation, the core and the aluminum-plastic film have gaps with different spacings, and the coating fills the gaps with different spacings.
[0016] In one implementation, the side surface of the core along the width and / or length direction includes an arcuate surface, and the gap is formed between the arcuate surface and the aluminum-plastic film.
[0017] In one implementation, the aluminum-plastic film has a folded edge on the side of the core along the width and / or length direction, and the gap is formed between the core and the folded edge.
[0018] In one implementation, the battery cell is a wound battery cell.
[0019] A second aspect of this application provides an electrical device including a body on which a lithium-ion battery as described in the first aspect above is mounted.
[0020] The technical solution provided in this application may include the following beneficial effects:
[0021] The lithium-ion battery provided in this application has a coating of a specific material applied to the side edges of the winding core corresponding to the gaps. This coating promotes heat dissipation or absorbs heat from the side edges of the winding core. This configuration effectively enhances the heat dissipation capacity of the lithium-ion battery, reduces the temperature rise during charging and discharging, and thus improves the battery's charging and discharging capacity and lifespan. Furthermore, while enhancing the heat dissipation capacity and reducing the temperature rise during charging and discharging, this solution does not alter the thickness of the current collector, and therefore does not affect the energy density of the lithium-ion battery.
[0022] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description
[0023] The above and other objects, features and advantages of this application will become more apparent from the more detailed description of exemplary embodiments thereof in conjunction with the accompanying drawings, wherein the same reference numerals generally represent the same components in the exemplary embodiments thereof.
[0024] Figure 1 This is a schematic diagram of the structure of a lithium-ion battery core, as shown in related technologies.
[0025] Figure 2 This is a schematic diagram of the core structure of a lithium-ion battery as shown in an embodiment of this application.
[0026] Reference numerals: 100, lithium-ion battery; 110, core; 111, side; 120, aluminum-plastic film; 121, gap; 122, coating; 123, folded edge. Detailed Implementation
[0027] Preferred embodiments of the present application will now be described in more detail with reference to the accompanying drawings. While preferred embodiments of the present application are shown in the drawings, it should be understood that the present application may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to make the present application more thorough and complete, and to fully convey the scope of the present application to those skilled in the art.
[0028] The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The singular forms “a,” “the,” and “the” used in this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more of the associated listed items.
[0029] It should be understood that although the terms "first," "second," "third," etc., may be used in this application to describe various information, this information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another. For example, without departing from the scope of this application, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.
[0030] In the description of this application, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and 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.
[0031] 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 or an electrical connection; 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. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.
[0032] Figure 1 This is a schematic diagram of the core structure of a lithium-ion battery, as shown in related technologies. See also... Figure 1 In related technologies, a certain gap 121 exists between the two sides of the wound core 110 of a wound lithium-ion battery and the aluminum-plastic film 120. During heat dissipation, this gap 121 involves gas-solid transfer, resulting in low heat transfer efficiency. When... Figure 1 The temperature distribution of the lithium-ion battery shown is recorded by an infrared detector during discharge. The temperature in the side area of the cell is often higher than that in the middle area of the cell.
[0033] To address the aforementioned issues, this application provides a winding core that enhances the heat dissipation capacity of the battery cell, reduces the temperature rise during charging and discharging, and does not affect the energy density of the battery cell.
[0034] The technical solutions of the embodiments of this application are described in detail below with reference to the accompanying drawings.
[0035] Figure 2 This is a schematic diagram of the structure of a lithium-ion battery core shown in an embodiment of this application.
[0036] See Figure 2 This application provides a lithium-ion battery 100, which includes a core 110 and an aluminum-plastic film 120 covering the periphery of the core 110. There is a gap 121 between the core 110 and the aluminum-plastic film 120. The side 111 of the core 110 corresponding to the gap 121 is coated with a coating 122 of a set material. The coating 122 is used to promote heat dissipation or absorb heat from the side 111 of the lithium-ion battery 100. For example, the temperature of the middle region of the lithium-ion battery is 25.8 degrees Celsius, while the temperature of the side region of the battery reaches 43.3 degrees Celsius.
[0037] Figure 2 In the diagram, the width direction of the core is the X-axis, and the thickness direction is the Y-axis. The side 111 of the core can be a side along the width or length direction of the core.
[0038] The lithium-ion battery of this application can be a soft-pack lithium-ion battery. The soft-pack lithium-ion battery is flexible and malleable. The battery core is formed by layering positive electrode material, separator and negative electrode material through winding.
[0039] Aluminum-laminated film (ALF) is a key material for packaging soft-pack lithium-ion battery cells. It is a high-strength, high-barrier multilayer composite material composed of various plastics, aluminum foil, and adhesives. The aluminum-laminated film 120 serves to protect the core 110 and its internal contents.
[0040] In this application, the core 110 is coated with a coating 122 of a specific material on its side 111 corresponding to the gap 121. This coating 122 promotes heat dissipation or absorbs heat from the side 111 of the lithium-ion battery 100. This configuration effectively enhances the heat dissipation capacity of the lithium-ion battery 100, reduces the temperature rise during charging and discharging, and makes the temperature more uniform in the central and side regions of the battery, thereby improving the battery's charging and discharging capacity and lifespan. Furthermore, while this application enhances the heat dissipation capacity of the lithium-ion battery 100 and reduces the temperature rise during charging and discharging, it does not change the thickness of the current collector, thus not affecting the energy density of the lithium-ion battery 100.
[0041] In this embodiment, the outer side of the coating 122, away from the core, contacts the inner side of the aluminum-plastic film 120. The material of the coating 122 is a material with solid-solid heat transfer properties. Solid-solid heat transfer refers to the process of heat transfer between solids, the basic principle of which is that heat is transferred from a high-temperature solid to a low-temperature solid through the contact interface. In this application, the core 110 and the aluminum-plastic film 120 are indirectly connected by a material with solid-solid heat transfer properties. Therefore, the heat generated on the side 111 of the core can be transferred to the aluminum-plastic film 120 through the solid-solid heat transfer of the coating, and then the aluminum-plastic film 120 releases the heat to the outside, thereby accelerating the heat dissipation of the side 111 of the core.
[0042] In some embodiments, the material possessing solid-solid heat transfer properties is at least one of polypropylene, polycarbonate, nylon, or polyimide, but is not limited thereto. In this application, as the temperature increases, the thermal conductivity of polypropylene also increases, thereby accelerating the rate of heat transfer; as the temperature increases, the movement of polycarbonate molecular chains intensifies, and the intermolecular interaction forces weaken, which is beneficial for heat transfer. In this application, polyimide can be prepared by a solid-state method and has high thermal conductivity, thereby enhancing the solid-solid heat transfer efficiency.
[0043] In some embodiments, the material of coating 122 is a material with solid-gas heat transfer properties. Solid-gas heat transfer refers to the process of heat transfer between a solid and a gas. The basic principle is that heat is transferred from a high-temperature object to a low-temperature gas or solid through a contact interface. In this application, since the core 110 and the aluminum-plastic film 120 are indirectly connected through coating 122, the heat generated on the side 111 of the core 110 can be transferred to the aluminum-plastic film 120 through solid-gas heat transfer via the coating, and then the aluminum-plastic film 120 releases the heat to the outside, thereby accelerating the heat dissipation of the side 111 of the core 110.
[0044] In some embodiments, the coating 122 is made of a material with a microporous structure. A microporous structure refers to a structure in which a large number of tiny pores exist within the material. These pores can be closed or open. The microporous structure increases the contact area between the solid and the gas, thereby improving heat transfer efficiency. The walls of the pores serve as heat transfer interfaces, allowing heat to be transferred more quickly from the side 111 of the core 110 into the gas, further enhancing the heat dissipation of the side 111 of the core 110.
[0045] In some embodiments, the material possessing solid-gas heat transfer properties or having a microporous structure is at least one of porous ceramics, porous carbon materials, or nanomaterials. Porous ceramics are ceramic materials with high porosity, their internal structure containing numerous micropores. These pores can be open (interconnected) or closed (independent). Porous ceramics have high porosity, up to 90%, providing numerous gas channels that facilitate gas diffusion and permeation, thereby enhancing heat dissipation at the side 111 of the core 110. Porous carbon materials contain numerous pores, which can be interconnected or closed, forming a complex pore network, thus providing numerous gas channels that facilitate gas diffusion and permeation, further enhancing heat dissipation at the side 111 of the core 110. The tiny particles and large specific surface area of nanomaterials can significantly increase the contact area between the solid and the gas, thereby improving heat transfer efficiency.
[0046] In some embodiments, the material of coating 122 has a specific heat capacity higher than a set value, i.e., a high specific heat capacity material. In this application, a high specific heat capacity material refers to a material whose unit mass absorbs a higher amount of heat when the temperature rises by 1 degree Celsius. Under the same mass and the same temperature rise, a high specific heat capacity material can absorb and store more thermal energy. Furthermore, because high specific heat capacity materials exhibit relatively small temperature changes when absorbing heat, they can maintain a more stable temperature and are less prone to drastic temperature fluctuations, thereby preventing a sharp increase in temperature on the side 111 of the lithium-ion battery 100.
[0047] In some embodiments, the material of the coating 122 with a specific heat capacity higher than a set value is at least one of ceramic, paraffin, or modified polymer materials, but is not limited thereto.
[0048] See also Figure 2 In some embodiments, gaps 121 with different spacings exist between the core 110 and the aluminum-plastic film 120, and the coating fills these gaps 121. The coating's structure can be adapted to the shape or structure of the gaps 121 between the core 110 and the aluminum-plastic film 120, increasing the contact area between the coating 122 and the sides 111 of the core 110 and the aluminum-plastic film 120, enhancing the structural stability of the aluminum-plastic film, and simultaneously improving the heat dissipation or heat absorption performance of the lithium-ion battery.
[0049] In some embodiments, the side surface of the core 110 along the width and / or length direction includes an arcuate surface, and a gap 121 is formed between the arcuate surface and the aluminum-plastic film 120.
[0050] In some embodiments, the aluminum-plastic film 120 has a folded edge 123 on the side of the core 110 along the width and / or length direction, and a gap 121 is formed between the lithium-ion battery 100 and the folded edge 123. Folding refers to a process of bending the aluminum-plastic film outside the lithium-ion battery to form an edge. Its main purpose is to ensure the integrity and safety of the battery structure, prevent electrolyte leakage inside the battery, and also help improve the battery's aesthetic appearance. In this application, folded edges 123 are provided on both sides along the width direction of the lithium-ion battery.
[0051] In the production process of lithium-ion battery 100, the aluminum-plastic film 120 shell needs to be folded in half so that both sides of the film shell tightly wrap around the core 110. Then, the edges of the film shell are sealed by a heat-sealing process to ensure the battery's airtightness. After folding and heat-sealing, the grooved edge of the aluminum-plastic film 120 is folded towards the side 111 of the aluminum-plastic film 120 shell that wraps the core 110, thereby forming a folded edge 123. The coating 122 of this application is applied between the folded edge 123 and the side 111 of the core 110.
[0052] This application also provides an electrical device, including a body on which a lithium-ion battery 100 as described in any of the above embodiments is mounted. This electrical device may be a mobile communication device, audio equipment, game console, smart door lock, etc., but is not limited thereto. The lithium-ion battery of this application provides power to the electrical device.
[0053] Since the electrical device of this application includes a lithium-ion battery as described in the above embodiment, the side 111 of the core 110 of the lithium-ion battery 100 corresponding to the gap 121 is coated with a coating 122 of a specified material. The coating 122 is used to promote heat dissipation or absorb heat from the side 111 of the lithium-ion battery 100. This configuration effectively enhances the heat dissipation capacity of the lithium-ion battery 100, reduces the temperature rise during charging and discharging, improves the charging and discharging capacity and battery life of the lithium-ion battery, and thus enhances the battery life of the electrical device and the user experience.
[0054] The solution proposed in this application involves setting a coating in the gap between the lithium-ion battery core and the aluminum-plastic film. This heat dissipation solution does not increase the thickness of the lithium-ion battery current collector, and therefore does not reduce the energy density of the lithium-ion battery.
[0055] The various embodiments of this application have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or improvement of the technology in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.
Claims
1. A lithium-ion battery, characterized by, Comprising: a core and an aluminum plastic film wrapped around the periphery of the core; a gap between the core and the aluminum plastic film, the side of the core corresponding to the gap being coated with a coating layer of a specified material, the coating layer being used to promote heat dissipation or absorb heat of the side of the core.
2. The lithium ion battery of claim 1, wherein: the material of the coating layer is a material with solid-solid heat transfer performance.
3. The lithium ion battery of claim 2, wherein: the material with solid-solid heat transfer performance is one of polypropylene, polycarbonate, nylon or polyimide.
4. The lithium ion battery of claim 1, wherein: the material of the coating layer is a material with solid-gas heat transfer performance; or, the material of the coating layer is a material with microporous structure.
5. The lithium ion battery of claim 4, wherein: the material with solid-gas heat transfer performance or the material with microporous structure is one of porous ceramic, porous carbon material or nanomaterial.
6. The lithium ion battery of claim 1, wherein: the material of the coating layer has a specific heat capacity higher than a specified value; or, the material of the coating layer is one of ceramic, paraffin or modified polymer material.
7. The lithium ion battery of claim 1, wherein: the gap between the core and the aluminum plastic film has different intervals, and the coating layer is filled in the gaps with different intervals.
8. The lithium ion battery of claim 1, wherein: the side surface of the core along the width and / or length direction includes an arc surface, and the gap is formed between the arc surface and the aluminum plastic film.
9. The lithium ion battery of claim 1, wherein: the aluminum plastic film has a folded edge portion at the side of the core along the width and / or length direction, and the gap is formed between the core and the folded edge portion.
10. An electrical device, characterized by Comprising: a body, the body being mounted with the lithium ion battery as claimed in any one of claims 1-9.