Battery cover heat dissipation film
By introducing a combination of a protective layer and an exhaust layer into the heat dissipation film of the battery cover, the problems of low mechanical strength and interfacial thermal resistance of the high thermal conductivity graphite layer are solved, achieving efficient heat conduction and improved heat dissipation performance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- GUANGDONG HONGTAI NEW MATERIAL TECHNOLOGY CO LTD
- Filing Date
- 2025-07-28
- Publication Date
- 2026-06-26
AI Technical Summary
Existing battery cover heat dissipation materials suffer from low thermal conductivity, heavy weight, or complex manufacturing processes. Furthermore, the high thermal conductivity graphite layer has low mechanical strength and is prone to breakage. Tiny air gaps can easily remain between the battery cover and the graphite film, leading to a significant reduction in interfacial thermal resistance and thermal conduction efficiency.
The heat dissipation film structure includes a protective layer, a high thermal conductivity graphite layer, and an exhaust layer. The protective layer is placed above the high thermal conductivity graphite layer to enhance mechanical strength, and the exhaust layer is placed below to expel tiny air particles, ensuring close contact between the battery cover and the heat dissipation film and reducing interface thermal resistance.
It significantly improves the thermal conductivity of the battery cover, enhances the overall reliability and durability of the heat dissipation film, optimizes heat dissipation performance, reduces the risk of breakage of the high thermal conductivity graphite layer, and improves heat transfer efficiency.
Smart Images
Figure CN224417836U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of heat dissipation film technology, and in particular to a heat dissipation film for a battery cover. Background Technology
[0002] With the widespread application of new energy power batteries, lithium batteries, energy storage batteries and other equipment, their performance is constantly improving, and their power and energy density are continuously increasing. These devices generate a lot of heat during operation. If heat cannot be dissipated in a timely and effective manner, it will seriously affect the battery's lifespan, safety and performance. Graphite heat dissipation film body is widely used in the field of battery cover heat dissipation due to its high thermal conductivity.
[0003] In related technologies, traditional heat dissipation materials, such as metal heat sinks and thermally conductive silicone, have drawbacks such as low thermal conductivity, large weight, or complex manufacturing processes. Graphite, on the other hand, is widely used in the thermal management of communication equipment due to its excellent planar thermal conductivity.
[0004] However, a single high thermal conductivity graphite layer has low mechanical strength and is easily broken. In traditional battery structures, tiny air gaps are easily left between the battery cover and the graphite film. The presence of these air thermal resistance layers will significantly reduce the interface thermal conduction efficiency, forming a double thermal resistance barrier. Utility Model Content
[0005] To address the aforementioned issues, this application provides a battery cover heat dissipation film.
[0006] The battery cover heat dissipation film provided in this application adopts the following technical solution:
[0007] A battery cover heat dissipation film includes a heat dissipation film body, the heat dissipation film body includes a protective layer, a high thermal conductivity graphite layer and an exhaust layer, the thickness of the high thermal conductivity graphite layer is 0.025mm.
[0008] By adopting the above technical solution, and superimposing a protective layer on the high thermal conductivity graphite layer, the mechanical strength of the high thermal conductivity graphite layer is significantly improved. This effectively disperses external stress and impact, reducing the risk of breakage due to the inherent brittleness of the high thermal conductivity graphite layer during processing and use. This ensures the integrity and reliability of the heat dissipation film body. The venting layer is located at the contact interface between the heat dissipation film body and the battery cover. When the heat dissipation film body and the battery cover are attached, it efficiently expels any residual micro-air between them, reducing the interfacial thermal resistance layer formed by air retention. This significantly improves the heat conduction efficiency from the battery cover to the graphite layer and optimizes the heat dissipation performance of the heat dissipation film body.
[0009] Preferably, the protective layer is disposed above the high thermal conductivity graphite layer, and the venting layer is disposed below the high thermal conductivity graphite layer.
[0010] By adopting the above technical solution, the protective layer is placed above the high thermal conductivity graphite layer, which significantly enhances the mechanical strength of the overall structure and effectively reduces the cracking of the high thermal conductivity graphite layer under external stress. At the same time, the venting layer is placed below the high thermal conductivity graphite layer and directly faces the battery cover. During the bonding process, it can efficiently expel the tiny air between the interfaces, reduce the interface thermal resistance layer formed by air retention between the battery cover and the heat dissipation film body, significantly improve the heat conduction efficiency from the battery cover to the graphite layer, and optimize the heat dissipation performance of the heat dissipation film body.
[0011] Preferably, the protective layer is a black PET film with a thickness of 0.015 mm.
[0012] By adopting the above technical solution, the protective layer is specifically set as a 0.015mm thick black PET film. The excellent mechanical strength of PET material effectively protects the underlying high thermal conductivity graphite layer from impact and breakage, significantly improving the overall reliability and durability of the heat dissipation film body. At the same time, the black PET film itself has a certain auxiliary heat dissipation capacity, and the thickness of 0.015mm ensures the lightweight of the overall structure of the heat dissipation film body. While providing sufficient protection, it maximizes the maintenance of the low thermal resistance and high thermal conductivity characteristics of the heat dissipation film body.
[0013] Preferably, the venting layer is configured as a venting adhesive, and the thickness of the venting layer is 0.03 mm.
[0014] By adopting the above technical solution, the venting layer is set as a venting adhesive with a thickness of 0.03mm. This not only provides effective adhesion and fixation to the battery cover, but also allows the venting adhesive to expel residual air between the battery cover and the heat dissipation film body when pressed and bonded, reducing micro gaps and interfacial thermal resistance. At the same time, the 0.03mm adhesive layer thickness precisely balances the filling and thermal conduction requirements. While ensuring complete filling and air isolation, it minimizes the additional thermal resistance generated by the venting adhesive and improves the efficiency of heat transfer from the battery cover to the high thermal conductivity graphite layer.
[0015] Preferably, the density of the high thermal conductivity graphite layer is 2.080 g / cm³.
[0016] By adopting the above technical solution, the density of the high thermal conductivity graphite layer reaches 2.080 g / cm³, indicating that the internal graphite crystal structure of the high thermal conductivity graphite layer is highly dense and orderly arranged, which significantly improves the planar thermal conductivity of the graphite layer itself. At the same time, this high density gives the high thermal conductivity graphite layer higher mechanical strength, enhances the deformation resistance under the condition of a thickness of 0.025 mm, and works in synergy with the upper and lower protective layers and exhaust layers to ensure the heat diffusion capability and improve the overall structural stability and durability of the heat dissipation film body.
[0017] Preferably, the thermal conductivity of the high thermal conductivity graphite layer is in the range of 2014 W / Mk to 2090 W / Mk.
[0018] By adopting the above technical solution, the thermal conductivity of the high thermal conductivity graphite layer ranges from 2014 W / Mk to 2090 W / Mk. It can efficiently and quickly spread the heat from the hot spot area of the battery cover laterally and evenly transfer it to the surface of the entire heat dissipation film. With a bonding density of 2.080 g / cm³, the thermal conductivity of the high thermal conductivity graphite layer minimizes the thermal resistance during heat transfer within the graphite layer. Working in synergy with the protective layer and the venting layer, it significantly overcomes the thermal resistance barrier formed by insufficient thermal conductivity of the material itself and the interfacial air thermal resistance in traditional battery heat dissipation structures, thereby improving the heat dissipation performance of the heat dissipation film.
[0019] Preferably, the thermal diffusivity of the high thermal conductivity graphite layer is in the range of 1140-1160 mm^2 / s.
[0020] By adopting the above technical solution, the thermal diffusivity of the high thermal conductivity graphite layer is as high as 1140-1160 mm² / s, which indicates that heat can diffuse at an extremely high speed inside the high thermal conductivity graphite layer. Combined with the thermal conductivity range of 2014 W / Mk-2090 W / Mk, this characteristic enables the 0.025 mm thick graphite layer to not only conduct heat efficiently, but also reduce the thermal resistance barrier formed by the material's thermal diffusion lag and the interfacial air thermal resistance in traditional heat dissipation structures, thereby improving the uniformity and stability of heat dissipation of the battery cover under heat load.
[0021] Preferably, the heat dissipation film body is provided with clearance space.
[0022] By adopting the above technical solution, a clearance space is set on the heat dissipation film body to avoid the protruding structure on the battery cover. This ensures that the heat dissipation film body can be completely flat and adhered to the surface of the battery cover, maintaining the venting adhesive. Thus, under complex structural conditions, both the low thermal resistance conduction path of the thermal interface and the overall structural integrity of the heat dissipation film body are guaranteed.
[0023] In summary, this application includes at least one of the following beneficial technical effects:
[0024] 1. By superimposing a protective layer on the high thermal conductivity graphite layer, the mechanical strength of the high thermal conductivity graphite layer is significantly improved, external stress and impact are effectively dispersed, and the problem of easy breakage of the high thermal conductivity graphite layer due to its own brittleness during processing and use is reduced. This ensures the integrity and reliability of the heat dissipation film body. The venting layer is located at the contact interface between the heat dissipation film body and the battery cover. When the heat dissipation film body and the battery cover are attached, the residual tiny air between the heat dissipation film body and the battery cover is efficiently discharged, reducing the interface thermal resistance layer formed by air retention between the battery cover and the heat dissipation film body. This significantly improves the heat conduction efficiency from the battery cover to the graphite layer and optimizes the heat dissipation performance of the heat dissipation film body.
[0025] 2. The protective layer is set as a 0.015mm thick black PET film. The mechanical strength of the black PET film effectively protects the high thermal conductivity graphite layer and reduces impact breakage. At the same time, the black PET film has an auxiliary heat dissipation function. The thickness of 0.015mm ensures the lightweight of the overall structure of the heat dissipation film body. While ensuring the reliability of the heat dissipation film body, it maintains low thermal resistance and high thermal conductivity.
[0026] 3. The venting layer is designed as a 0.03mm thick venting adhesive, which not only provides effective adhesion and fixation to the battery cover, but also actively removes residual air between the battery cover and the heat dissipation film body when the venting adhesive is pressed and bonded, eliminating the interfacial air gap thermal resistance and significantly improving the heat transfer efficiency from the battery cover to the high thermal conductivity graphite layer. Attached Figure Description
[0027] Figure 1 This is a structural schematic diagram of an embodiment of this application.
[0028] Figure 2 This is a cross-sectional view of an embodiment of this application.
[0029] Explanation of reference numerals in the attached diagram: 1. Heat dissipation film body; 11. Protective layer; 12. High thermal conductivity graphite layer; 13. Exhaust layer; 14. Clearance space. Detailed Implementation
[0030] The following is in conjunction with the appendix Figure 1-2 This application will be described in further detail.
[0031] This application discloses a battery cover heat dissipation film. (Refer to...) Figure 1 and Figure 2 A battery cover heat dissipation film includes a heat dissipation film body 1, wherein the heat dissipation film body 1 is composed of a protective layer 11, a high thermal conductivity graphite layer 12 and an exhaust layer 13. This structure enables the heat dissipation film body 1 to effectively dissipate heat from the battery cover of new energy batteries.
[0032] Furthermore, the protective layer 11 significantly improves the mechanical strength of the high thermal conductivity graphite layer 12, effectively disperses external stress and impact, and reduces the problem of easy breakage of the high thermal conductivity graphite layer 12 due to its own brittleness during processing and use, thus ensuring the integrity and reliability of the heat dissipation film body 1. The exhaust layer 13 is located at the contact interface between the heat dissipation film body 1 and the battery cover. When the heat dissipation film body 1 and the battery cover are attached, it efficiently exhausts the residual tiny air between the heat dissipation film body 1 and the battery cover, reduces the interface thermal resistance layer formed by air retention between the battery cover and the heat dissipation film body 1, significantly improves the heat conduction efficiency from the battery cover to the graphite layer, and optimizes the heat dissipation performance of the heat dissipation film body 1.
[0033] Specifically, the protective layer 11 is set as a black PET film. The black PET film has good flexibility and wear resistance. Its black color may have the function of absorbing light and converting it into heat energy to assist in heat dissipation. The PET film is made of polyethylene terephthalate.
[0034] The black PET film is placed on top of the high thermal conductivity graphite layer 12. The excellent mechanical strength of the PET material effectively protects the high thermal conductivity graphite layer 12 from impact and breakage, significantly improving the overall reliability and durability of the heat dissipation film body 1. At the same time, the black PET film itself has a certain auxiliary heat dissipation capacity, and its thickness of 0.015mm ensures the lightweight of the overall structure of the heat dissipation film body 1. While providing sufficient protection, it maximizes the maintenance of the low thermal resistance and high thermal conductivity characteristics of the heat dissipation film body 1.
[0035] Furthermore, the high thermal conductivity graphite layer 12 is made of graphite material, which has a unique layered crystal structure. This structure gives the high thermal conductivity graphite layer 12 extremely high thermal conductivity in the horizontal direction.
[0036] Specifically, the high thermal conductivity graphite layer 12 has a thickness of 0.025 mm, a density of 2.080 g / cm³, a thermal conductivity ranging from 2014 W / Mk to 2090 W / Mk, and a thermal diffusivity ranging from 1140 to 1160 mm² / s.
[0037] This indicates that the high thermal conductivity graphite layer 12 has a density of 2.080 g / cm³, which means that the internal graphite crystal structure of the high thermal conductivity graphite layer 12 is highly dense and orderly arranged, significantly improving the planar thermal conductivity of the high thermal conductivity graphite layer 12 itself. At the same time, this high density gives the high thermal conductivity graphite layer 12 higher mechanical strength, enhancing its resistance to deformation under the condition of a thickness of 0.025 mm. Together with the upper and lower protective layers 11 and the exhaust layer 13, it not only ensures the heat diffusion capability, but also improves the overall structural stability and durability of the heat dissipation film body 1.
[0038] Furthermore, the thermal diffusivity of the high thermal conductivity graphite layer 12 is as high as 1140-1160 mm² / s, which indicates that heat can diffuse at an extremely high speed inside the high thermal conductivity graphite layer 12. Combined with the thermal conductivity range of 2014 W / Mk-2090 W / Mk, this characteristic enables the 0.025 mm thick graphite layer to efficiently conduct heat and evenly spread concentrated heat along the plane, significantly suppressing the temperature rise of hot spots. This effectively reduces the thermal resistance barrier formed by the material's thermal diffusion lag and the superposition of interfacial air thermal resistance in traditional heat dissipation structures, thereby greatly improving the heat dissipation uniformity and stability of the battery cover under heat load.
[0039] On the other hand, the venting layer 13 is disposed below the high thermal conductivity graphite layer 12. The venting layer 13 is configured as a venting adhesive with a thickness of 0.03 mm. The venting adhesive not only provides effective bonding and fixation with the battery cover, but also can expel the air remaining between the battery cover and the heat dissipation film body 1 when pressed and bonded, reducing the micro gaps and the resulting interfacial thermal resistance. At the same time, the 0.03 mm adhesive layer thickness precisely balances the filling and heat conduction requirements. Under the premise of ensuring complete filling and air isolation, it minimizes the additional thermal resistance generated by the venting adhesive and improves the efficiency of heat transfer from the battery cover to the high thermal conductivity graphite layer 12.
[0040] The combination logic of these three layers is as follows: first, the high thermal conductivity graphite layer 12 is prepared, then the protective layer 11 is attached above the high thermal conductivity graphite layer 12, and the exhaust layer 13 is attached below. The combined effect is that the protective layer 11 protects the high thermal conductivity graphite layer 12 from external damage, the high thermal conductivity graphite layer 12 is responsible for efficiently conducting heat, and the exhaust layer 13 exhausts gas. The three work together to greatly improve the heat dissipation performance and stability of the heat dissipation film body 1.
[0041] Furthermore, in this embodiment, the composite process of the heat dissipation film body 1 is to first hot-press a black PET protective film onto the upper surface of the high thermal conductivity graphite layer 12, then uniformly coat the lower surface of the high thermal conductivity graphite layer 12 with exhaust adhesive, and finally complete the three-layer integrated composite under controlled temperature and pressure.
[0042] In addition, the heat dissipation film body 1 is provided with a clearance space 14, which can avoid the protruding structure on the battery cover. This ensures that the heat dissipation film body 1 can be completely flat and adhered to the surface of the battery cover, maintaining the venting adhesive. Thus, under complex structural conditions, it simultaneously ensures the low thermal resistance conduction path of the thermal interface and the overall structural integrity of the heat dissipation film body 1.
[0043] The implementation principle of the battery cover heat dissipation film in this application embodiment is as follows:
[0044] This embodiment employs a high thermal conductivity graphite layer, with a protective layer superimposed on top and an venting layer superimposed below. The protective layer significantly enhances the mechanical strength of the high thermal conductivity graphite layer, effectively dispersing external stress and impact, and reducing the risk of breakage due to its inherent brittleness during processing and use. The venting layer, located at the contact interface between the heat dissipation film body and the battery cover, efficiently removes residual micro-air between them when they are attached, reducing the interfacial thermal resistance layer formed by air retention and significantly improving the heat transfer efficiency from the battery cover to the graphite layer, thus optimizing the heat dissipation performance of the heat dissipation film body.
[0045] The protective layer is a black PET film, which covers the graphite layer. The flexibility and abrasion resistance of PET provide mechanical protection, while the black color helps absorb radiant heat. The 0.015mm thickness maintains low thermal resistance. The high thermal conductivity graphite layer has a density of 2.080g / cm³, a thermal conductivity of 2014W / Mk-2090W / Mk, and a thermal diffusivity of 1140-1160mm² / s. The high thermal conductivity graphite layer allows for rapid heat conduction and diffusion. Air venting adhesive is applied under the graphite layer to expel air and fill gaps during bonding, eliminating the interfacial thermal resistance layer and simultaneously bonding and fixing the battery cover.
[0046] After plasma activation on the surface of the high thermal conductivity graphite layer, a PET film is hot-pressed onto the upper surface, and an exhaust adhesive is precisely coated on the lower surface. Temperature and pressure control are used to achieve a three-layer integrated composite.
[0047] The heat dissipation film body is punched to avoid the protrusion of the battery cover, ensuring that the heat dissipation film body and the battery cover fit flatly and closely, maintaining the venting effect and reducing local damage.
[0048] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.
Claims
1. A battery cover heat dissipation film, characterized in that, It includes a heat dissipation film body (1), which includes a protective layer (11), a high thermal conductivity graphite layer (12) and an exhaust layer (13), wherein the thickness of the high thermal conductivity graphite layer (12) is 0.025 mm.
2. The battery cover heat dissipation film according to claim 1, characterized in that, The protective layer (11) is disposed above the high thermal conductivity graphite layer (12), and the exhaust layer (13) is disposed below the high thermal conductivity graphite layer (12).
3. The battery cover heat dissipation film according to claim 2, characterized in that, The protective layer (11) is a black PET film with a thickness of 0.015 mm.
4. The battery cover heat dissipation film according to claim 2, characterized in that, The venting layer (13) is configured as venting adhesive, and the thickness of the venting layer (13) is 0.03 mm.
5. A battery cover heat dissipation film according to claim 2, characterized in that, The density of the high thermal conductivity graphite layer (12) is 2.080 g / cm³.
6. The battery cover heat dissipation film according to claim 2, characterized in that, The thermal conductivity of the high thermal conductivity graphite layer (12) is in the range of 2014 W / Mk to 2090 W / Mk.
7. The battery cover heat dissipation film according to claim 1, characterized in that, The thermal diffusivity of the high thermal conductivity graphite layer (12) is in the range of 1140-1160 mm^2 / s.
8. The battery cover heat dissipation film according to claim 1, characterized in that, The heat dissipation film body (1) is provided with a clearance space (14).