Battery box body, battery and electric automobile

Abstract

The invention belongs to the technical field of electric automobiles, and discloses a battery box body, a battery and an electric automobile, the battery box body comprises a bottom plate and a frame, the bottom plate comprises a foamed aluminum core plate, and the upper end face and the lower end face of the foamed aluminum core plate are each fixedly connected with at least one outer layer plate. The thermal protection performance of the box body can be improved, and the bottom collision resistance can be improved due to the high-energy absorption capacity of the foamed aluminum, so that the safety of the electric automobile is effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of electric vehicles, and in particular to a battery box, a battery and an electric vehicle. Background Art

[0002] With the rapid development of new energy vehicle technology, the performance and reliability of high-voltage power distribution systems have received increasing attention. There are already some patent solutions involving batteries in the prior art. For example, the Chinese invention patent battery discloses a box and a vehicle, and the box adopts an aluminum profile bottom plate. In the field of battery systems, in order to improve safety and achieve thermal and electrical separation or adopt integrated technologies such as CTB / CTC to prevent the battery cell from directly spraying valves into the passenger compartment when it is thermally out of control, more and more cases have the battery cell explosion-proof valve facing downward to the bottom plate of the box. The temperature of the gas ejected when the battery cell is thermally out of control is as high as 1000°C or more, while the melting point of aluminum is only about 660°C, which cannot meet the demand. It is necessary to add additional thermal protection materials such as mica boards to improve performance, increase manufacturing processes and costs. In addition, the bottom guard plate structure of the battery box and the battery box specification of the Chinese invention patent also disclose the integrated design of the bottom guard plate and the liquid cooling plate in order to reduce weight and realize the integration of the bottom guard plate and the liquid cooling plate. Although it proposes the use of foam aluminum as the bottom plate of the box, the thermal protection function is not considered. Although the foam aluminum box has improved thermal protection performance compared with the aluminum plate and profile box, it cannot fully meet the demand. Therefore, it is urgent to develop a battery box with strong thermal protection performance. Summary of the invention

[0003] In order to solve or partially solve the problems existing in the related art, the purpose of the present invention is to provide a battery case, a battery and an electric vehicle, which can not only improve the thermal protection performance of the case, but also improve the bottom collision resistance due to the high energy absorption capacity of the foamed aluminum itself, thereby effectively improving the safety of the electric vehicle.

[0004] To achieve the above objectives, in a first aspect, the present invention provides a battery box, including a bottom plate and a frame, wherein the bottom plate includes a foam aluminum core plate, and the upper end surface and the lower end surface of the foam aluminum core plate are each fixedly connected to at least one outer layer plate.

[0005] In some embodiments of the present invention, the foam aluminum core plate and the outer layer plate have corresponding shapes.

[0006] In some embodiments of the present invention, the outer plate is an aluminum plate, an aluminum alloy plate, a magnesium alloy plate, a steel plate or a fiber reinforced plastic plate.

[0007] In some embodiments of the present invention, the foam aluminum core board is an aerogel-based composite foam aluminum board.

[0008] In some embodiments of the present invention, the aerogel-based composite foam aluminum plate is integrated with a thermal protection material.

[0009] In some embodiments of the present invention, the heat protection material is mica powder.

[0010] In some embodiments of the present invention, the content of aerogel or mica powder in the foam aluminum core board is adjusted according to the severity of thermal runaway of different battery cells.

[0011] In some embodiments of the present invention, the foam aluminum plate and the outer plate are connected by gluing, screwing, riveting, brazing, and laser beam welding.

[0012] The invention also discloses a battery, which comprises a battery box.

[0013] The invention also discloses an electric vehicle, which comprises a battery.

[0014] The beneficial effects of the present invention are as follows: the battery case, battery and electric vehicle provided by the present invention have significant advantages and practical value. First, the use of a foam aluminum core board as the core structure of the bottom plate greatly improves the thermal protection performance of the case. The melting point of foam aluminum is much higher than that of ordinary aluminum, and it can effectively resist the high-temperature gas generated when the battery cell is thermally runaway. More importantly, the present invention innovatively integrates thermal protection materials into the foam aluminum core board, further enhancing the ability of the case to resist thermal runaway of the battery cell and providing a more comprehensive thermal protection solution.

[0015] Secondly, aluminum foam itself has excellent energy absorption capacity, which significantly improves the bottom collision resistance of the battery box. This feature provides a higher level of safety for electric vehicles, especially in the event of a collision, it can better protect the battery system, thereby comprehensively improving the safety of electric vehicles.

[0016] The present invention forms a sandwich structure by fixing the outer layer plates at the upper and lower ends of the foam aluminum core plate. This design not only further enhances the overall strength and rigidity of the bottom plate, but also provides better sealing and protection capabilities. The material selection of the outer layer plate is flexible, and different metals or composite materials can be selected according to specific needs to meet different performance requirements.

[0017] One particularly noteworthy advantage is that the box design of the present invention integrates multiple functions such as heat protection and bottom protection. This highly integrated design concept avoids the need for additional heat protection materials and bottom guard plates, thereby significantly simplifying the manufacturing process and assembly process. This not only reduces production hours, but also effectively reduces overall manufacturing costs, providing a more cost-effective solution for the electric vehicle industry.

[0018] In addition, the present invention introduces the innovative concept of aerogel-based composite foam aluminum plate and proposes a solution of integrating thermal protection materials (such as mica powder). This design allows the content of aerogel or mica powder to be flexibly adjusted according to the thermal runaway characteristics of different battery cells, achieving more precise thermal management and safety protection. This adjustability provides customized protection solutions for battery systems of different types and specifications.

[0019] Finally, the present invention provides a variety of connection options, such as gluing, screws, riveting, brazing and laser beam welding, etc., to ensure a reliable connection between the foam aluminum plate and the outer plate, while providing a flexible assembly solution for different production conditions and application scenarios.

[0020] The present invention successfully solves the problem of insufficient thermal protection performance of battery boxes in the prior art by innovatively applying foamed aluminum materials, composite structural design and functional integration, while improving the anti-collision capability and significantly enhancing the overall safety of electric vehicles. This series of improvements not only helps to improve the reliability and performance of new energy vehicles, but also provides new ideas and possibilities for the lightweight and integrated design of battery systems. By simplifying the manufacturing process and reducing costs, the present invention provides a more competitive and sustainable technical path for the development of the electric vehicle industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments disclosed in the present invention, the drawings of the embodiments will be briefly introduced below. These drawings are only used for illustrative purposes and are not intended to limit the protection scope of the present invention.

[0022] Figure 1 is a schematic diagram of a battery box of the present invention;

[0023] Figure 2 It is a schematic diagram of the bottom plate of the battery box of the present invention;

[0024] Figure 3 is a schematic diagram of a base plate of the present invention;

[0025] Figure 4 It is a schematic diagram of a base plate of the present invention. DETAILED DESCRIPTION

[0026] The technical solution of the present invention (including the preferred technical solution) is further described in detail below by means of the accompanying drawings and by listing some optional embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] The battery box proposed in the present invention is designed to solve the safety challenges faced by new energy vehicle battery systems. With the rapid development of electric vehicle technology, battery safety has become the focus of industry attention. Especially in the case of thermal runaway of the battery cell, the traditional battery box structure often cannot provide sufficient protection. The present invention provides a solution that can provide effective protection and reduce costs through innovative material application and structural design.

[0028] like Figure 1-4 As shown, the basic structure of the battery box includes two main parts: a frame 1 and a bottom plate 2. Among them, the bottom plate 2 adopts an innovative foam aluminum sandwich material structure, which is the core of the present invention. This structure consists of a foam aluminum core plate 21 and an outer plate 22, forming a sandwich composite structure. Specifically, the foam aluminum core plate 21 is placed between two outer plates 22 and is firmly combined by a variety of connection methods. This design not only provides excellent thermal protection performance, but also gives the box good mechanical strength and vibration reduction capabilities.

[0029] The connection between the foam aluminum core plate 21 and the outer plate 22 is one of the key links of this design. According to different application scenarios and performance requirements, a variety of connection methods can be selected, including gluing, screw fixing, riveting, brazing or laser beam welding. Each connection method has its own characteristics and applicable situations. For example, adhesive connection is suitable for large areas and light loads, and has good sealing; screw fixing is easy to disassemble and repair; riveting is suitable for thin plate connection and has high connection strength; brazing and laser beam welding can provide the highest connection strength and sealing, suitable for high-demand application scenarios.

[0030] The material selection of the outer plate 22 is also a highlight of this design. According to different performance requirements and cost considerations, a variety of materials can be selected, such as aluminum plates, aluminum alloy plates, magnesium alloy plates, steel plates or fiber reinforced plastic plates. Each material has its own unique advantages: aluminum plates and aluminum alloy plates have good thermal conductivity and lightweight properties; magnesium alloy plates have advantages in further weight reduction; steel plates provide the highest strength and rigidity; fiber reinforced plastic plates excel in lightweight and corrosion resistance. This flexible material selection allows the battery box to be optimized according to specific application requirements.

[0031] Another innovation of the present invention is that thermal protection material is integrated into the foam aluminum core plate 21, which greatly improves the ability of the battery box to resist thermal runaway of the battery cell. There are two main implementation methods for this design, each of which has its own unique advantages and applicability.

[0032] The first method is to use aerogel-based composite aluminum foam board. During the preparation of aluminum foam, aerogel 23 material is evenly distributed in the aluminum foam structure. Aerogel is a super insulating material with extremely low thermal conductivity, even lower than that of still air. More importantly, aerogel has extremely high temperature resistance and can withstand temperatures up to 1200°C without significant performance degradation. This property enables aerogel-based composite aluminum foam board to provide excellent thermal protection performance when facing thermal runaway of battery cells. The porous structure of aerogel can further enhance the thermal insulation effect of aluminum foam, forming an efficient thermal barrier.

[0033] The second method is to add mica powder during the foaming process of aluminum foam24. Mica powder is a natural mineral material with a layered structure and excellent high temperature resistance, and can withstand a high temperature of up to 1130°C. Evenly mixing mica powder into the aluminum foam material can not only improve the high temperature resistance of aluminum foam, but also enhance its mechanical strength and insulation performance. The layered structure of mica powder can effectively block heat transfer and provide additional thermal protection for aluminum foam. In addition, the addition of mica powder can also improve the pore structure of aluminum foam and further optimize its thermal protection performance.

[0034] An important advantage of these two methods is their adjustability. According to the thermal runaway characteristics and severity of different battery cells, the content of aerogel or mica powder can be flexibly adjusted to achieve a customized thermal protection solution. For example, for battery systems with a higher risk of thermal runaway, the content of aerogel or mica powder can be increased; while for systems with better thermal management, the content can be appropriately reduced to balance the cost. This flexibility enables the present invention to adapt to a variety of different application scenarios and safety requirements.

[0035] As the core material of the present invention, the unique structure and performance of foamed aluminum are the key to achieving efficient thermal protection. Foamed aluminum is a new type of solid-gas composite material, which contains a large number of evenly distributed pores inside, and these pores occupy 60%-98% of the material volume. It is this unique porous structure that gives foamed aluminum many excellent properties. Although the melting point of pure aluminum is only about 660°C, specially treated foamed aluminum can burn at a high temperature of 1000°C for 30 minutes without obvious deformation. This excellent high temperature resistance is mainly due to two factors: one is the dense oxide layer formed on the pore wall structure of the foamed aluminum, and the other is the intermetallic compounds distributed between the pore walls. These structures work together to effectively prevent the rapid transfer of heat, thereby achieving excellent fire resistance.

[0036] In addition to its excellent thermal protection, aluminum foam also has a number of excellent physical and mechanical properties. Its density is very low, usually only 5%-25% of the same volume of pure aluminum, which makes aluminum foam have high specific strength and specific stiffness. At the same time, aluminum foam also has high energy absorption capacity, high damping performance and low thermal conductivity. These characteristics make the aluminum foam box reduce the weight while significantly improving the energy absorption and vibration buffering capacity of the battery bottom.

[0037] When an electric vehicle is hit from the bottom, the traditional solid metal box may directly transmit the impact force to the internal battery system. However, the foam aluminum box can absorb a large amount of impact energy through its porous structure and convert it into plastic deformation energy of the material. This energy absorption mechanism can greatly reduce the impact force transmitted to the battery system, thereby significantly reducing the vibration, extrusion and impact strength of the battery cells in the battery system. This not only reduces the probability of battery short circuit, but also further reduces the risk of battery pack fire or explosion, improving the overall safety of electric vehicles from multiple levels.

[0038] Furthermore, this embodiment of the present invention also proposes an adaptive thermal protection foam aluminum base plate system, which can automatically adjust the content distribution of aerogel or mica powder in the foam aluminum according to the thermal runaway characteristics of different types of battery cells, thereby achieving the optimal thermal protection effect.

[0039] 1. System composition: a) Foam aluminum base plate with partition design b) Aerogel / mica powder injection system c) Temperature monitoring system d) Control unit.

[0040] 2. Bottom plate partition design: The foam aluminum bottom plate is divided into multiple independent areas, each area corresponds to a different module or single battery in the battery pack. This partition design allows differentiated thermal protection treatment for batteries in different positions.

[0041] 3. Aerogel / mica powder injection system: During the manufacturing process of the foam aluminum base plate, a fine channel network is reserved. These channels are connected to the external aerogel or mica powder storage tank. Through a precise pumping system, different proportions of aerogel or mica powder mixtures can be injected into the designated area.

[0042] 4. Temperature monitoring system: Install high-precision temperature sensors in each partition to monitor the temperature changes in each area in real time. These sensors can respond quickly to temperature changes and provide accurate temperature data for the control unit.

[0043] 5. Control Unit: The control unit is the brain of the entire system. It receives data from the temperature monitoring system and decides whether the thermal protection material content in a certain area needs to be adjusted based on a preset algorithm. The control unit is also connected to the on-board diagnostic system and can obtain battery status information.

[0044] 6. Workflow: a) Initial setting: According to the basic characteristics of different types of cells in the battery pack, the initial aerogel / mica powder content of each partition is set. b) Real-time monitoring: The temperature monitoring system continuously monitors the temperature of each partition and transmits the data to the control unit. c) Data analysis: The control unit combines temperature data and battery status information to evaluate the thermal runaway risk of each partition. d) Dynamic adjustment:

[0045] If the temperature of a certain partition rises abnormally or the battery status shows a risk of thermal runaway, the control unit will instruct the injection system to increase the content of aerogel or mica powder to that area. e) Feedback optimization: The system continuously learns and optimizes, and adjusts the warning threshold and response strategy based on historical data.

[0046] 7. Safety mechanism: Set up multiple safety protection measures, including overpressure relief valves, emergency isolation systems, etc., to ensure that the system can be safe and controllable under extreme circumstances.

[0047] 8. Feasibility analysis: a) Material feasibility: Aerogel and mica powder are both mature thermal protection materials that can be stably present in the foam aluminum structure. b) Process feasibility: The partition design and microchannel network can be realized through advanced 3D printing technology. c) Control feasibility: Modern cars have widely used complex electronic control systems, and the control logic of this system can be integrated into the existing battery management system. d) Economic feasibility: Although the initial cost may be high, it will be economically beneficial in the long run by improving safety and extending battery life.

[0048] This embodiment achieves the goal of flexibly adjusting the content of thermal protection materials according to the thermal runaway characteristics and severity of different battery cells by transforming the static thermal protection design into a dynamic adaptive system. The system can not only provide more accurate thermal protection, but also dynamically optimize according to the actual use of the battery and environmental changes, greatly improving the safety and reliability of the battery system.

[0049] The present invention not only solves the problem that the traditional aluminum bottom plate is easy to melt at high temperatures, but also avoids the need to add additional heat protection materials such as mica plates and bottom guard plates. This integrated design greatly simplifies the manufacturing process and reduces production costs. At the same time, the multifunctional integrated design of the foam aluminum box provides electric vehicles with a safer, lightweight and cost-effective battery protection solution, providing a new technical path for the development of the new energy vehicle industry.

[0050] Those skilled in the art will readily appreciate that the above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, combinations, replacements, improvements, etc. made within the spirit and principles of the present invention are included within the protection scope of the present invention.

Claims

1. A battery box, comprising a bottom plate (2) and a frame (1), characterized in that: The bottom plate (2) comprises a foam aluminum core plate (21), and the upper end surface and the lower end surface of the foam aluminum core plate (21) are each fixedly connected to at least one outer layer plate (22).

2. The battery box according to claim 1, characterized in that: The foam aluminum core plate (21) and the outer layer plate (22) have corresponding shapes.

3. The battery box according to claim 1, characterized in that: The outer plate (22) is an aluminum plate, an aluminum alloy plate, a magnesium alloy plate, a steel plate or a fiber-reinforced plastic plate.

4. The battery case according to claim 1, characterized in that: The foam aluminum core plate (21) is an aerogel-based composite foam aluminum plate.

5. The battery case according to claim 1 or 4, characterized in that: The foam aluminum core plate (21) is integrated with a heat protection material.

6. The battery case according to claim 5, characterized in that: The heat protection material is mica powder (24).

7. The battery case according to claim 6, characterized in that: The content of aerogel (23) or mica powder (24) in the foam aluminum core plate (21) is adjusted according to the severity of thermal runaway of different battery cells.

8. The battery case according to claim 6, characterized in that: The foam aluminum plate (21) and the outer plate (22) are connected in a manner including gluing, screwing, riveting, brazing, and laser beam welding.

9. A battery, characterized in that: The battery comprises a battery case as claimed in any one of claims 1 to 8.

10. An electric vehicle, characterized in that: The electric vehicle comprises the battery according to claim 9.

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