Heat exchange battery box and battery module

Abstract

The invention relates to the technical field of new energy, in particular to a heat exchange battery box and a battery module. The battery module comprises a heat exchange battery box and a battery cell arranged in a containing cavity of the heat exchange battery box, the heat exchange battery box comprises a box wall, and the surface of the box wall is in contact with the battery cell; wherein the box wall is provided with a flow channel, the flow channel is used for being filled with a heat exchange agent and enabling the heat exchange agent to flow in the flow channel, and the inner wall of the flow channel is coated with a heat dissipation coating and / or a resistance reduction coating. The heat exchange battery box can be used for assembling batteries to form a battery module, and the heat exchange efficiency of the batteries can be improved by the heat exchange battery box, so that the problem that the batteries are easily damaged at too high or too low temperature is solved.

Description

Technical Field

[0001] This invention relates to the field of new energy technology, and more specifically, to a heat exchange battery box and a battery module. Background Technology

[0002] Lithium-ion batteries have advantages such as high energy density, long lifespan, and high cycle life, and are widely used in various fields, with huge potential for future market development.

[0003] In the energy storage field, the battery generates enormous heat during charging and discharging. A sustained increase in temperature can prevent this heat from dissipating properly, potentially leading to thermal runaway and serious accidents such as fires and explosions. Conversely, excessively low battery temperatures negatively impact performance, reducing the released specific capacity. In other words, both excessively high and low temperatures accelerate battery capacity degradation. Furthermore, uneven temperature distribution on individual cell surfaces can create stress, potentially causing irreversible damage and affecting the overall electrical performance of the module.

[0004] Therefore, in order to ensure the stability of the battery under high load, extend its service life, and ensure safety, it is necessary to ensure the temperature stability of the battery to avoid the battery temperature being too high or too low.

[0005] To heat the battery, it is usually assembled in a heat exchange battery box. The heat exchanger filled in the flow channels of the battery box heats the battery, thereby improving the problem of the battery temperature being too high or too low.

[0006] However, the heat exchange battery boxes provided by related technologies have low efficiency in exchanging heat with batteries, which can still easily lead to damage to the batteries at excessively high or low temperatures. Summary of the Invention

[0007] The present invention aims to provide a heat exchange battery box and a battery module. The heat exchange battery box can be used to assemble batteries to form a battery module, and the heat exchange battery box can improve the heat exchange efficiency of the battery to improve the problem that the battery is easily damaged at excessively high or low temperatures.

[0008] The embodiments of the present invention can be implemented as follows: In a first aspect, the present invention provides a heat exchange battery box, comprising: The casing wall, the surface of which contacts the battery cell; among which, The tank wall is provided with flow channels for filling heat exchanger and allowing the heat exchanger to flow within the flow channels. The inner wall of the flow channels is coated with a heat dissipation coating and / or a drag reduction coating.

[0009] In an optional implementation, the box wall is provided with multiple flow channels; the multiple flow channels are arranged sequentially along the width direction of any flow channel.

[0010] In an optional implementation, two adjacent flow channels are interconnected.

[0011] In an optional embodiment, the thickness of the heat-dissipating coating is 40±5μm.

[0012] In an optional embodiment, the heat dissipation coating includes at least one of a graphene heat dissipation coating, an aluminum nitride ceramic coating, and a magnesium oxide ceramic coating.

[0013] In an optional embodiment, the thickness of the drag-reducing coating is 30±5μm.

[0014] In an optional embodiment, the drag-reducing coating includes a polytetrafluoroethylene coating.

[0015] In an optional implementation, the box wall is the bottom wall of the heat exchange battery box, used to support the battery cells.

[0016] In an optional embodiment, the box walls are made of aluminum alloy.

[0017] In a second aspect, the present invention provides a battery module, including a battery cell and a heat exchange battery box according to any of the foregoing embodiments; wherein the heat exchange battery box has a receiving cavity, the battery cell is assembled in the receiving cavity and contacts the box wall.

[0018] The beneficial effects of the heat exchange battery box provided in the embodiments of the present invention include: the heat exchange battery box provided in the embodiments of the present invention includes a box wall, and the surface of the box wall is in contact with the battery cell; wherein, the box wall is provided with a flow channel, the flow channel is used to fill the heat exchanger and allow the heat exchanger to flow in the flow channel, and the inner wall of the flow channel is coated with a heat dissipation coating and / or a drag reduction coating.

[0019] With a heat dissipation coating applied to the inner wall of the flow channel, the high thermal conductivity of the heat dissipation coating can be used to accelerate the heat exchange efficiency between the cell and the heat exchanger in the flow channel, ensuring that the temperature of the cell assembled in the heat exchange battery box remains stable and uniform, improving the problem of excessively high or low cell temperature, and thus ensuring the stability and cycle life of the cell.

[0020] When the inner wall of the flow channel is coated with a drag-reducing coating, the flow rate (efficiency) of the heat exchanger in the flow channel can be improved, thereby improving the heat exchange efficiency between the cell and the heat exchanger in the flow channel, ensuring that the temperature of the cell assembled in the heat exchange battery box remains stable and uniform, improving the problem of excessively high or low cell temperature, and thus ensuring the stability and cycle life of the cell.

[0021] The battery module provided in this embodiment of the invention includes all the beneficial effects of the aforementioned heat exchange battery box, such as: improving the heat exchange efficiency between the battery cell and the heat exchanger in the flow channel, ensuring that the temperature of the battery cell assembled in the heat exchange battery box remains stable and uniform, improving the problem of excessively high or low battery cell temperature, and thus ensuring the stability and cycle life of the battery cell. Attached Figure Description

[0022] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the structure of the box wall in an embodiment of the present invention; Figure 2 This is a cross-sectional view of the box wall in an embodiment of the present invention.

[0024] Icons: 100 - Box wall; 110 - Flow channel; 120 - Inner wall; 130 - Outer wall in contact with the battery cell. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0026] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0027] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0028] In the description of this invention, it should be noted that if terms such as "upper," "lower," "inner," or "outer" are used to indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this invention is usually placed, they are only for the convenience of describing this invention 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 invention.

[0029] Furthermore, the terms "first" and "second" are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0030] It should be noted that, where there is no conflict, the features in the embodiments of the present invention can be combined with each other.

[0031] This embodiment provides a battery module, which includes a battery cell and a heat exchange battery box. The heat exchange battery box has a receiving cavity, the battery cell is assembled in the receiving cavity, and the box wall 100 of the heat exchange battery box is in contact with it.

[0032] The performance of lithium-ion batteries is closely related to temperature. At low temperatures, the battery's electrical performance is affected, leading to a reduction in specific capacity. While at high temperatures, although the battery's electrical performance improves, side reactions also increase, thus shortening its cycle life. In addition, uneven temperature distribution on the surface of individual cells can generate stress, potentially causing irreversible damage to the battery and affecting the electrical performance of the entire module.

[0033] To maintain the temperature stability and uniformity of the battery cells and mitigate issues of excessively high or low cell temperatures, please refer to... Figure 1 and Figure 2 The casing wall 100 is provided with flow channels 110, which are used to fill heat exchanger and allow the heat exchanger to flow within the flow channels 110. The inner wall 120 of the flow channels 110 is coated with a heat dissipation coating and / or a drag-reducing coating. By utilizing the heat exchanger in the flow channels 110 to exchange heat with the battery cells in the housing cavity, the temperature of the battery cells can be effectively maintained, the problem of excessively high or low battery cell temperatures can be improved, and the uniformity of battery cell temperature can be enhanced.

[0034] In some embodiments, the inner wall 120 of the flow channel 110 is coated only with a heat dissipation coating. The high thermal conductivity of the heat dissipation coating can be used to accelerate the heat exchange efficiency between the cell and the heat exchanger in the flow channel 110, ensuring that the temperature of the cell assembled in the heat exchange battery box remains stable and uniform, improving the problem of excessively high or low cell temperature, and thus ensuring the stability and cycle life of the cell.

[0035] In other embodiments, the inner wall 120 of the flow channel 110 is coated only with a drag-reducing coating, which can improve the flow rate (efficiency) of the heat exchanger in the flow channel 110, thereby improving the heat exchange efficiency between the cell and the heat exchanger in the flow channel 110, ensuring that the temperature of the cell assembled in the heat exchange battery box remains stable and uniform, improving the problem of excessively high or low cell temperature, and thus ensuring the stability and cycle life of the cell.

[0036] In some other embodiments, a portion of the inner wall 120 of the flow channel 110 is coated with a drag-reducing coating, and another portion is coated with a heat-dissipating coating. In this way, the high thermal conductivity of the heat-dissipating coating can be used to accelerate the heat exchange efficiency between the battery cell and the heat exchanger in the flow channel 110, and the drag-reducing coating can be used to increase the flow rate of the heat exchanger, thereby improving the heat exchange efficiency between the battery cell and the heat exchanger in the flow channel 110.

[0037] Optionally, the box wall 100 is provided with multiple flow channels 110; the multiple flow channels 110 are arranged sequentially along the width direction of any flow channel 110.

[0038] In some embodiments, the inner walls 120 of all flow channels 110 are coated with a heat-dissipating coating.

[0039] In other embodiments, the inner walls 120 of all flow channels 110 are coated with a drag-reducing coating.

[0040] In some other embodiments, a portion of the inner wall 120 of the flow channel 110 is coated with a heat dissipation coating, while another portion of the inner wall 120 of the flow channel 110 is coated with a drag-reducing coating.

[0041] Optionally, two adjacent flow channels 110 are interconnected.

[0042] Of course, in other embodiments, the multiple channels 110 are not interconnected.

[0043] Optionally, the flow channel 110 has a rectangular cross-section and includes four inner walls 120 connected in sequence. One of the inner walls 120 is close to the outer wall 130 of the casing wall 100 that contacts the battery cell. The inner wall 120 is coated with a heat dissipation coating and / or a resistance reduction coating.

[0044] Of course, in other embodiments, the heat dissipation coating and / or drag reduction coating may also be applied to other inner walls 120 besides the aforementioned inner wall 120.

[0045] Optionally, the thickness of the heat dissipation coating is 40±5μm, such as 35μm, 38μm, 40μm, 42μm, 45μm, etc., and no specific limitation is made here.

[0046] Optionally, the heat dissipation coating includes at least one of a graphene heat dissipation coating, an aluminum nitride ceramic coating, and a magnesium oxide ceramic coating.

[0047] The following example illustrates the process of applying a 40μm thick graphene heat dissipation coating to the flow channel 110.

[0048] The graphene heat dissipation coating has high thermal conductivity, which can accelerate the heat exchange between the heat exchanger (e.g., refrigerant) in the flow channel 110 and the battery cell placed in the cavity, thereby improving heat dissipation efficiency. At the same time, the unique structure of graphene allows the coating to form a dense physical barrier on the inner wall 120 of the flow channel 110, reducing the penetration of media such as moisture and oxygen. This not only enhances corrosion resistance but also reduces the surface friction coefficient, indirectly reducing flow resistance, allowing the refrigerant to pass through the flow channel 110 quickly, avoiding heat accumulation, and further improving cooling efficiency.

[0049] It should be noted that in embodiments where the graphene heat dissipation coating is replaced with an aluminum nitride ceramic coating or a magnesium oxide ceramic coating, the same high thermal conductivity is achieved, and the heat conduction principle is similar to that of the graphene heat dissipation coating, so it will not be described again here.

[0050] Optionally, the thickness of the drag-reducing coating is 30±5μm, such as 25μm, 27μm, 30μm, 33μm, 35μm, etc., and no specific limitation is made here.

[0051] Optionally, the drag-reducing coating includes a polytetrafluoroethylene (PTFE) coating.

[0052] The following explanation uses a 30μm thick polytetrafluoroethylene coating as an example.

[0053] Optionally, the heat dissipation coating and / or drag reduction coating can be applied to the inner wall 120 of the flow channel 110 by spraying, brushing or other methods, and then dried and cured after application.

[0054] Polytetrafluoroethylene (PTFE) has properties such as low coefficient of friction, corrosion resistance, and temperature resistance. After the PTFE coating is applied, the flow resistance between the inner wall 120 of the flow channel 110 and the heat exchanger (e.g., refrigerant) is reduced. Under the same energy consumption and pressure, the heat exchanger (e.g., refrigerant) can carry away the heat generated by the battery cell more quickly, thereby improving the heat dissipation efficiency.

[0055] Optionally, the box wall 100 is the bottom wall of the heat exchange battery box, used to support the battery cells.

[0056] Of course, in other embodiments, the box wall 100 can also be the side wall or top wall of the heat exchange battery box, as long as it can contact the battery cells in the cavity for reliable heat exchange.

[0057] Optionally, the casing wall 100 is made of aluminum alloy, which helps to improve heat exchange efficiency.

[0058] Alternatively, the box wall 100 can be prepared by using aluminum alloy through die casting, welding, or other methods. The specific preparation process is similar to the related technologies and will not be described in detail here.

[0059] In summary, the heat exchange battery box of the present invention can be used to assemble batteries to form battery modules, and the heat exchange battery box can improve the heat exchange efficiency of the batteries, thereby improving the problem that the batteries are easily damaged at excessively high or low temperatures.

[0060] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A heat exchange battery box, characterized in that, include: A casing wall (100) has a surface that contacts the battery cell; wherein, The box wall (100) is provided with a flow channel (110), the flow channel (110) is used to fill the heat exchanger and allow the heat exchanger to flow in the flow channel (110), and the inner wall (120) of the flow channel (110) is coated with a heat dissipation coating and / or a drag reduction coating.

2. The heat exchange battery box according to claim 1, characterized in that, The box wall (100) is provided with a plurality of flow channels (110); the plurality of flow channels (110) are arranged sequentially along the width direction of any flow channel (110).

3. The heat exchange battery box according to claim 2, characterized in that, The two adjacent flow channels (110) are interconnected.

4. The heat exchange battery box according to claim 1, characterized in that, The thickness of the heat dissipation coating is 40±5μm.

5. The heat exchange battery box according to claim 1, characterized in that, The heat dissipation coating includes at least one of graphene heat dissipation coating, aluminum nitride ceramic coating, and magnesium oxide ceramic coating.

6. The heat exchange battery box according to claim 1, characterized in that, The thickness of the drag-reducing coating is 30±5μm.

7. The heat exchange battery box according to claim 1, characterized in that, The drag-reducing coating includes a polytetrafluoroethylene coating.

8. The heat exchange battery box according to claim 1, characterized in that, The box wall (100) is the bottom wall of the heat exchange battery box, used to support the battery cells.

9. The heat exchange battery box according to claim 1, characterized in that, The box wall (100) is made of aluminum alloy.

10. A battery module, characterized in that, It includes a battery cell and a heat exchange battery box as described in any one of claims 1-9; wherein the heat exchange battery box has a receiving cavity, the battery cell is assembled in the receiving cavity and contacts the box wall (100).

Images