A power battery box cover

Abstract

The application discloses a power battery box cover and belongs to the technical field of power battery safety, which is used for avoiding the problem of temperature non-uniformity in a battery pack caused by a heat preservation layer. The power battery box cover comprises a cover body, a metal heat reflection layer and a glue layer. The cover body has a first wall surface facing the power battery. The metal heat reflection layer is arranged on the first wall surface, and the metal heat reflection layer can reflect the heat of the power battery. The glue layer is arranged between the metal heat reflection layer and the first wall surface of the cover body, and the glue layer is fixedly connected with the metal heat reflection layer and the cover body. The metal heat reflection layer arranged on the cover body can radiate the heat of the battery, so that the heat of a high-temperature area can be conducted to a low-temperature area through the metal heat reflection layer, the temperature difference between the battery monomers is reduced, and temperature uniformization is achieved.

Description

Technical Field

[0001] This application relates to the field of power battery safety technology, and in particular to a power battery box cover. Background Technology

[0002] Power battery packs suffer rapid heat loss and uneven temperature distribution at low temperatures, which greatly reduces the battery's capacity and charge / discharge capabilities at low temperatures. Therefore, power battery pack covers are often insulated with materials such as polyurethane foam, polystyrene foam, aerogel, and fiberglass to reduce heat loss.

[0003] However, in cold regions, the working environment of power batteries often cannot reach a suitable temperature. Therefore, the battery pack is equipped with a heating structure. The temperature of the battery pack is increased by combining the heating structure with the heat insulation structure on the power battery box cover.

[0004] However, this structure can cause temperature differences in different areas of the battery pack, especially in cold weather. The insulation structure on the battery cover has a low thermal conductivity and absorbs and blocks heat radiation, resulting in different insulation effects on areas with different temperatures. Heat is difficult to dissipate within the battery pack through convection, further leading to temperature differences within the battery pack.

[0005] Uneven temperature not only affects the charging and discharging efficiency of the battery and shortens its lifespan, but when the temperature difference within the battery pack is too large, the batteries in the high-temperature area may also cause thermal runaway due to overheating, leading to greater danger. Utility Model Content

[0006] This application provides a power battery box cover to avoid the problem of uneven temperature inside the battery pack caused by the insulation layer.

[0007] This application provides a power battery box cover, including a cover body, a metal heat reflective layer and an adhesive layer; the cover body has a first wall facing the power battery; the metal heat reflective layer is disposed on the first wall, and the metal heat reflective layer can reflect the heat of the power battery; the adhesive layer is disposed between the metal heat reflective layer and the first wall of the cover body, and the adhesive layer fixes the metal heat reflective layer and the cover body.

[0008] This application utilizes a metallic heat-reflective layer on the cover body to reflect battery heat, allowing heat from high-temperature areas to be conducted to lower-temperature areas. This helps reduce temperature differences between individual battery cells, achieving temperature uniformity. Uniform battery temperature contributes to improved battery lifespan, stable charge / discharge rates, and reduces the risk of battery explosion due to heat.

[0009] The adhesive layer ensures a stable connection between the metal heat-reflective layer and the cover body. The installation process of the metal heat-reflective layer and adhesive layer on the cover body is simple, which helps to reduce production costs and improve production efficiency.

[0010] In some embodiments of this application, the metal heat-reflective layer is a metal foil layer. Metal foil layers are simple to produce, low in cost, and have good heat radiation reflection effects.

[0011] In some embodiments of this application, the metal heat-reflective layer includes at least two metal foil layers, which are fixedly stacked. Each metal foil layer can reflect thermal radiation, and the multi-layer foil structure is equivalent to setting multiple reflective interfaces. When thermal radiation passes through the multi-layer metal foil, it will be reflected multiple times between the layers, so that more thermal radiation is reflected back, reducing the transmittance of thermal radiation and enhancing the thermal radiation effect; at the same time, it makes the overall strength of the metal heat-reflective layer higher.

[0012] In some embodiments of this application, adjacent metal foil layers are fixedly bonded together. Bonded metal foil layers can give the metal heat-reflective layer stable strength and better stability during operation.

[0013] In some embodiments of this application, the metal heat-reflective layer is made of one or more of copper, silver, and aluminum. Copper, silver, and aluminum all have good heat radiation reflection capabilities.

[0014] In some embodiments of this application, a metal coating is further disposed on the metal heat reflective layer. The metal coating may also have the ability to reflect metal heat radiation.

[0015] In some embodiments of this application, the metal coating is one or more of titanium dioxide, zinc oxide, tin oxide, and aluminum oxide. These metal coatings not only have good heat reflectivity but also good corrosion resistance and a long service life.

[0016] In some embodiments of this application, a fire-fighting chamber is provided on the cover body, the fire-fighting chamber is located on the first wall surface away from the cover body, and a fire-fighting interface is formed on the fire-fighting chamber for installing fire-fighting equipment; the power battery box cover also includes a solenoid valve, which is disposed in the fire-fighting chamber and is used to be installed on the fire-fighting equipment, and is used to be electrically connected to the vehicle battery management system.

[0017] The opening and closing of the solenoid valve is controlled by the BMS (Battery Management System). Based on the thermal runaway warning signal transmitted by the BMS, the solenoid valve can be controlled in conjunction with the vehicle's fire suppression system to achieve targeted fire suppression, thereby further improving the safety of the power battery.

[0018] In some embodiments of this application, multiple fire-fighting interfaces are provided, and each fire-fighting interface is equipped with a fire-fighting device and a solenoid valve. Multiple fire-fighting interfaces can be equipped with multiple solenoid valves and multiple fire-fighting devices, thereby providing better fire-fighting capabilities.

[0019] In some embodiments of this application, the edge of the cover body is folded away from the first wall surface to form a fire-fighting cavity on the cover body. This method can reduce the thickness of the cover body, which is conducive to the lightweight design of the cover. Attached Figure Description

[0020] The accompanying drawings are provided to further illustrate the technical solution of this utility model and constitute a part of the specification. They are used together with the embodiments of this application to explain the technical solution of this utility model and do not constitute a limitation on the technical solution of this utility model.

[0021] Figure 1 This is a schematic diagram of a power battery box cover provided in an embodiment of this application.

[0022] Figure 2 This is a schematic diagram illustrating one embodiment of a power battery box cover provided in this application.

[0023] Figure 3 This is a top view of a power battery box cover provided in an embodiment of this application.

[0024] Figure 4 This is a schematic diagram illustrating the working principle of a solenoid valve in a power battery box cover, provided as an embodiment of this application.

[0025] Reference numerals: 1-Cover body; 11-Fire chamber; 2-Metallic heat reflective layer; 21-Metal foil layer; 22-Metal coating; 3-Adhesive layer; 4-Solenoid valve. Detailed Implementation

[0026] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0027] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0028] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0029] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "connected" and "linked" should be interpreted broadly, for example, as a fixed connection, a detachable connection, or an integral connection. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances. Furthermore, when describing pipelines, the terms "connected" and "linked" as used in this application have the meaning of establishing electrical connection. The specific meaning needs to be understood in conjunction with the context.

[0030] In the embodiments of this application, the terms "exemplary" or "for example" are used to indicate that something is an example, illustration, or description. Any embodiment or design that is described as "exemplary" or "for example" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or design. Specifically, the use of the terms "exemplary" or "for example" is intended to present the relevant concepts in a specific manner.

[0031] Power battery packs suffer rapid heat loss and uneven temperature distribution at low temperatures, which greatly reduces the battery's capacity and charge / discharge capabilities at low temperatures. Therefore, power battery pack covers are often insulated with materials such as polyurethane foam, polystyrene foam, aerogel, and fiberglass to reduce heat loss.

[0032] However, in cold regions, the working environment of power batteries often cannot reach a suitable temperature. Therefore, the battery pack is equipped with a heating structure. The temperature of the battery pack is increased by combining the heating structure with the heat insulation structure on the power battery box cover.

[0033] However, this structure can cause temperature differences in different areas of the battery pack, especially in cold weather. The insulation structure on the battery cover has a low thermal conductivity and absorbs and blocks heat radiation, resulting in different insulation effects on areas with different temperatures. Heat is difficult to dissipate within the battery pack through convection, further leading to temperature differences within the battery pack.

[0034] Uneven temperature not only affects the charging and discharging efficiency of the battery and shortens its lifespan, but when the temperature difference within the battery pack is too large, the batteries in the high-temperature area may also cause thermal runaway due to overheating, leading to greater danger.

[0035] Therefore, please refer to Figure 1This application provides a power battery box cover, including a cover body 1, a metal heat reflective layer 2, and an adhesive layer 3.

[0036] Please refer to Figure 1 The cover body 1 has a first wall facing the power battery. The first wall is the inner wall of the cover body 1, which can be flat, square in shape, or have protrusions or depressions at the edges. The cover body 1 is the cover of the power battery, and its material can be aluminum alloy, copper alloy, or other composite materials.

[0037] Please refer to Figure 1 A metal heat-reflective layer 2 is disposed on the first wall surface, and the metal heat-reflective layer 2 can reflect the heat of the power battery. The metal heat-reflective layer 2 should have good heat reflection ability, such as copper, silver, or aluminum. The metal heat-reflective layer 2 can be a plate or a layered structure, and the thickness can be uniform. The metal heat-reflective layer 2 can cover all areas of the first wall surface of the cover, or gaps can be set at the edges to reduce the design and installation difficulty.

[0038] Please refer to Figure 1 The adhesive layer 3 is disposed between the metal heat reflective layer 2 and the first wall surface of the cover body 1, and the adhesive layer 3 fixes the metal heat reflective layer 2 and the cover body 1. The adhesive layer 3 is used to fix and bond the metal heat reflective layer 2 and the cover body 1. The adhesive layer 3 can be a thermally conductive structural adhesive, which can typically be composed of a base resin, thermally conductive filler, curing agent and other additives.

[0039] Please refer to Figure 1 This application utilizes a metal heat-reflective layer 2 disposed on the cover body 1 to reflect the heat of the battery. This allows heat from high-temperature areas to be conducted to low-temperature areas through the metal heat-reflective layer 2, helping to reduce temperature differences between individual battery cells and achieve temperature uniformity. Uniform battery temperature contributes to improved battery lifespan, stable charge / discharge rates, and reduces the risk of battery explosion due to heat.

[0040] Please refer to Figure 1 The adhesive layer 3 ensures a stable connection between the metal heat-reflective layer 2 and the cover body 1. The installation process of the metal heat-reflective layer 2 and the adhesive layer 3 on the cover is simple, which helps to reduce production costs and improve production efficiency.

[0041] In some other examples, the cover body 1 and the metal heat reflective layer 2 can also be bonded together with an insulating adhesive layer 3, which can be polyurethane foam or silicone rubber insulating adhesive, thereby providing a better insulation effect and reducing heat loss.

[0042] Please refer to Figure 1In some examples, the metal heat reflective layer 2 is a metal foil layer 21. The metal foil layer 21 is simple to produce, low in cost, and has a good effect on reflecting heat radiation.

[0043] In some examples, the foil layer structure is thin and lightweight, which does not add too much burden to the object and is easy to carry and install; the metal foil layer 21 has excellent barrier properties and can effectively block the transmission of gases, water vapor, light and so on, thus protecting the internal items.

[0044] Please refer to Figure 2 In some examples, the metallic heat-reflective layer 2 includes at least two layers of metal foil 21, which are fixedly stacked. Each layer of metal foil can reflect thermal radiation, and the multi-layer foil structure is equivalent to setting multiple reflective interfaces. When thermal radiation passes through the multi-layer metal foil, it will be reflected multiple times between the layers, so that more thermal radiation is reflected back, reducing the transmittance of thermal radiation and enhancing the thermal radiation effect; at the same time, it makes the overall strength of the metallic heat-reflective layer 2 higher.

[0045] Please refer to Figure 2 The thermal radiation effect of multiple layers of metal foil 21 is usually better.

[0046] First, the number of reflections can be increased. Each metal foil layer 21 can reflect thermal radiation. When thermal radiation passes through multiple layers of metal foil, it will be reflected multiple times between the layers, so that more thermal radiation is reflected back, reducing the transmittance of thermal radiation.

[0047] It can also enhance the scattering effect; the gaps between the multiple metal foil layers 21 cause thermal radiation to scatter. As thermal radiation propagates through these gaps, its direction constantly changes, increasing the path length of thermal radiation propagation within the foil structure. This makes it easier for thermal radiation to be absorbed or reflected by the metal foil during propagation, further reducing the transmittance of thermal radiation.

[0048] The multi-layer metal foil 21 can improve thermal insulation performance. The air layers or other thermal insulation media formed between the multi-layer metal foil 21 also help to improve the overall thermal insulation effect. These air layers or thermal insulation media have low thermal conductivity, which can prevent heat conduction and work together with the metal foil 21 to reduce the transfer of heat radiation.

[0049] Please refer to Figure 2 In some examples, the foil layers can be two, three, or other numbers of layers. Different foil layers can have the same thickness, the same size, and can be bonded together using the thermally conductive structural adhesive described above.

[0050] In some examples, adjacent metal foil layers 21 are fixedly bonded together. The bonded metal foil layers 21 can give the metal heat reflective layer 2 stable strength and better stability during operation.

[0051] In some examples, adjacent metal foil layers 21 can be bonded together with thermally conductive structural adhesive.

[0052] In some examples, the metal heat-reflective layer 2 is made of one or more of copper, silver, and aluminum. Copper, silver, and aluminum all have good heat radiation reflection capabilities.

[0053] In some examples, the metal heat reflective layer 2 can be a single material, or it can be formed by splicing together multiple materials, or it can be formed by stacking multiple materials.

[0054] Please refer to Figure 2 In some examples, a metal coating 22 is also provided on the metal heat reflective layer 2. The metal coating 22 may also have the ability to reflect metal heat radiation.

[0055] In some examples, the metal coating 22 does not damage the heat reflection effect of the original metal heat reflective layer 2, thus ensuring the temperature uniformity of the battery.

[0056] In some examples, the metal coating 22 is one or more of titanium dioxide, zinc oxide, tin oxide, and aluminum oxide. These metal coatings 22 not only have good heat reflection capabilities but also good corrosion resistance and a long service life.

[0057] In some examples, aluminum oxide has high hardness, melting point, and chemical stability; it can also reflect the thermal radiation of the battery, reduce heat loss, and improve energy efficiency.

[0058] Please refer to Figure 1 and Figure 3 In some examples, a fire chamber 11 is provided on the cover body 1. The fire chamber 11 is located on the first wall surface away from the cover body 1. A fire interface is formed on the fire chamber 11 for installing fire-fighting equipment. The power battery box cover also includes a solenoid valve 4, which is located in the fire chamber 11. The solenoid valve 4 is used to install fire-fighting equipment and is used to electrically connect with the vehicle battery management system.

[0059] The opening and closing of solenoid valve 4 is controlled by BMS (Battery Management System). Based on the thermal runaway warning signal transmitted by BMS, the solenoid valve 4 can be controlled in conjunction with the vehicle's fire suppression system to achieve targeted fire suppression, thereby further improving the safety of the power battery.

[0060] Please refer to Figure 3 In some examples, the fire-fighting cavity 11 can be a recessed groove opened on the upper wall of the cover body 1 away from the first wall, or it can be a hollow cavity.

[0061] Firefighting equipment can be fire sprinklers. When a fire occurs inside the battery pack, the fire sprinklers will spray extinguishing agents evenly into the battery pack after receiving the corresponding signal, thereby achieving the functions of extinguishing the fire and cooling down, controlling the spread of the fire and reducing the damage to the battery pack.

[0062] The model and type of solenoid valve 4 should be selected to correspond with the fire-fighting equipment in order to control the start and stop of the fire-fighting equipment.

[0063] Please refer to Figure 3 In some examples, multiple fire-fighting interfaces are configured, with each interface equipped with a fire-fighting device and a solenoid valve 4. Multiple fire-fighting interfaces can accommodate multiple solenoid valves 4 and multiple fire-fighting devices, thereby enhancing fire-fighting capabilities.

[0064] In some examples, there can be five fire hydrants, which can be completely identical or partially identical.

[0065] Please refer to Figure 3 In some examples, the edge of the cover body 1 is folded away from the first wall surface to form a fire-fighting cavity 11 located on the cover body 1. In this way, the thickness of the cover body 1 can be reduced, which helps to achieve a lightweight design of the entire cover.

[0066] Please refer to Figure 1 In some examples, the cover body 1 is made of sheet metal bending cover, the material can be HC340LA, and the thickness does not exceed 1mm; the whole body is first bent and folded to form an unsealed cube, the folded height does not exceed a certain height, and the last side is sealed with sheet metal flat plate, and the four sides are laser welded to form a cavity, which ensures that the cover is lightweight and also forms an air intake channel for external fire-fighting gas.

[0067] Please refer to Figure 3 Several solenoid valves 4 are arranged inside the fire chamber 11. Their specific positions are determined according to the distribution of energy areas inside the battery pack. The number of solenoid valves 4 is also related to the size of the battery pack. Each solenoid valve 4 is controlled by the BMS. External fire protection is controlled by the vehicle VCU. The BMS will transmit signals to the VCU, and the VCU will control the on / off of the fire protection system.

[0068] Please refer to Figure 3 and Figure 4 In some examples, there are five solenoid valves (4 in total): S1, S2, S3, S4, and S5. S1 is connected to a fire-extinguishing gas device, while S2, S3, S4, and S5 can be fire-extinguishing gases or other extinguishing media. For example:

[0069] Please refer to Figure 4The BMS will continuously monitor the thermal runaway alarm signal 24 hours a day (combined strategy). When the thermal runaway alarm signal is triggered, it will first send a signal to the VCU. The VCU will control the opening of the fire extinguishing system, and the inner cavity of the cabinet will be immediately vented with fire extinguishing gas.

[0070] The BMS will simultaneously open one or more corresponding solenoid valves 4 according to the corresponding area table of the battery cell and solenoid valve 4, so that the extinguishing gas can be quickly directed to the failed area, thereby achieving rapid directional fire suppression.

[0071] In the description of this specification, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0072] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A power battery box cover, characterized in that, include: The cover body has a first wall facing the power battery; A metal heat-reflective layer is disposed on the first wall surface, and the metal heat-reflective layer can reflect the heat of the power battery; An adhesive layer is disposed between the metal heat-reflective layer and the first wall surface of the cover body, and the adhesive layer fixes the metal heat-reflective layer and the cover body together.

2. The power battery box cover according to claim 1, characterized in that, The metal heat-reflective layer is a metal foil layer.

3. The power battery box cover according to claim 2, characterized in that, The metal heat reflective layer includes at least two layers of metal foil, which are fixedly stacked.

4. The power battery box cover according to claim 3, characterized in that, The two adjacent metal foil layers are fixedly bonded together.

5. The power battery box cover according to claim 1, characterized in that, The metal heat reflective layer is made of one or more of copper, silver, and aluminum.

6. The power battery box cover according to claim 5, characterized in that, The metal heat reflective layer is also provided with a metal coating.

7. The power battery box cover according to claim 6, characterized in that, The metal coating is one or more of titanium dioxide, zinc oxide, tin oxide, and aluminum oxide.

8. The power battery box cover according to any one of claims 1 to 7, characterized in that, The cover body is provided with a fire-fighting chamber, which is located on the wall surface away from the first wall surface of the cover body. A fire-fighting interface is formed on the fire-fighting chamber, which is used to install fire-fighting equipment. The power battery box cover also includes a solenoid valve, which is located inside the fire chamber and is used to be installed on the fire-fighting equipment. The solenoid valve is used to be electrically connected to the vehicle battery management system.

9. The power battery box cover according to claim 8, characterized in that, The fire-fighting interface is configured to be multiple, and each fire-fighting interface is equipped with a fire-fighting device and a solenoid valve.

10. The power battery box cover according to claim 8, characterized in that, The edge of the cover body is folded away from the first wall surface to form the fire-fighting cavity located on the cover body.

Images