Bottom protection device for battery pack and battery pack

Abstract

The invention relates to the technical field of battery protection, in particular to a bottom protection device for a battery pack and the battery pack. The battery pack comprises a battery box body used for placing battery cells, a bottom protection device used for protecting the battery box body is arranged below the battery box body, the bottom protection device comprises a bottom protection plate fixedly connected below the battery box body, two opposite edges of the bottom protection plate are respectively provided with a support plate, a protection plate is arranged between the two support plates, and the bottom protection plate is fixedly connected with the bottom protection plate. The two ends of the protection plate are connected with the corresponding supporting plates respectively, a gap is formed between the protection plate and the bottom protection plate, an air bag used for collision prevention and buffering is placed in the gap, and a flexible protection layer is formed between the bottom protection plate and the protection plate through the air bag. According to the device, the problem that an existing device is not ideal in protection effect can be solved, the flexible protection layer has the advantages of being high in buffering performance, light in weight and the like, the structure is simple, installation is convenient, and the manufacturing cost is low.

Description

Technical Field

[0001] The present invention relates to the technical field of battery protection, and in particular to a bottom protective plate for a battery pack. Background Art

[0002] New energy vehicles refer to vehicles that use new energy as a power source. Existing new energy vehicles mainly include electric vehicles, hybrid vehicles, and hydrogen fuel cell vehicles. Taking electric vehicles as an example, they have a power battery system as an energy storage device to provide energy for driving the vehicle. It is composed of one or more battery packs and a battery management system. Among them, the battery pack is the core component of the power battery system. It is extremely important and has a high cost. Most of them are installed at the bottom of the car and are easily bumped or scratched. In order to prevent the battery pack from being bumped or scratched by external forces, it is usually necessary to do some protection for the battery pack. In the existing technology, it is generally protected by an external bottom guard plate.

[0003] The utility model patent document with authorization announcement number CN2188867256U and authorization announcement date 2023 / 04 / 14 discloses a battery pack and a vehicle, which includes a bottom guard plate and a battery pack body arranged on the bottom guard plate; a sensor is arranged between the battery pack body and the bottom guard plate, and the sensor is electrically connected to the controller in the battery pack body; the sensor is used to detect the collision force signal received by the bottom guard plate, and the controller is used to generate the damage state of the bottom guard plate according to the collision force signal detected by the sensor, the battery pack body includes at least two columns of battery cell assemblies and at least one liquid cooling plate, the liquid cooling plate is arranged between two adjacent columns of the battery cell assemblies, and multiple sensors are arranged between each liquid cooling plate and the bottom guard plate.

[0004] When the underbody guard plate is hit by stones, scratches, collisions, etc., the sensor can detect the pressure signal of the underbody guard plate through deformation under force, which is then transmitted to the controller to generate the damaged status of the underbody guard plate and remind the driver. However, the design requirement of long-range driving makes the size of the power battery larger. When the number of sensors is small, it is difficult to cover the entire area of ​​the battery pack or the underbody guard plate. When the number is large, the cost increases and the production becomes complicated.

[0005] The utility model patent document with authorization announcement number CN220021379U and authorization announcement date 2023 / 11 / 14 discloses a battery pack, which includes a battery cell and a bottom guard plate, wherein the bottom guard plate is located on one side of the battery cell; an airbag is provided at the end of the bottom guard plate, and the airbag is located between the bottom guard plate and the battery cell, and the airbag can be converted from a deflated state to an inflated state through a gas generating device to separate the bottom guard plate and the battery cell.

[0006] When the bottom guard plate is impacted, the airbag can be switched to an inflated state to separate the bottom guard plate and the battery cell, thereby reducing the impact transmitted from the bottom guard plate to the battery cell, thereby protecting the battery cell. However, the impact received by the bottom guard plate needs to be large enough so that the vibration received by the gas generating device is large enough to complete the inflation of the airbag and protect the battery cell. For some minor bumps or jolts, the airbag is in a deflated state, and the battery cell is overlapped on the upper surface of the bottom guard plate and is hard-protected by the bottom guard plate. The protection of the battery cell is not always in a state, so the protection effect is not ideal. Summary of the invention

[0007] The object of the present invention is to provide a bottom protection device for a battery pack and a battery pack, so as to solve the problem that the airbag protection effect in the existing bottom protection device is not ideal.

[0008] In order to solve the above problems, a bottom protection device for a battery pack of the present invention adopts the following technical solutions: A bottom protection device for a battery pack comprises a bottom protection plate fixedly connected to the bottom of a battery box, support plates are respectively provided at two opposite edge positions of the bottom protection plate, a protective plate is provided between the two support plates, and both ends of the protective plate are respectively connected to the corresponding support plates, a gap is formed between the protective plate and the bottom protection plate, an airbag for anti-collision and buffering is placed in the gap, and a flexible protective layer is formed between the bottom protection plate and the protective plate through the airbag.

[0009] Furthermore, the two support plates are respectively provided with slide rail grooves with notches facing each other, and the two ends of the protective plate are respectively slidably connected to the corresponding slide rail grooves to form a drawer-type installation structure.

[0010] Furthermore, the two slide rail grooves are respectively provided with extension plates extending towards each other at the lower edge positions of the grooves, and each of the extension plates is respectively provided with a positioning hole, and the positioning holes are provided with pins for fixing the protective plate and the bottom guard plate.

[0011] Furthermore, sealants are respectively provided between the same ends of the two slide rail grooves to seal and form a sealed flexible protective layer.

[0012] Furthermore, the airbag is provided with elastic sealing strips at the arc edges on both sides close to the support plate.

[0013] Furthermore, the airbag is provided with multiple layers of wound fiber rubber cloth around its periphery, so that the airbag forms a rectangular shape to fit the gap between the protective plate and the bottom guard plate.

[0014] Furthermore, the airbag is provided with an air pressure sensor for monitoring the gas pressure in the airbag.

[0015] Furthermore, the airbag is provided with a plurality of air chambers, and each of the air chambers is provided with an air pressure sensor for monitoring the gas pressure in the airbag.

[0016] Furthermore, the protective plate is provided with stamping ribs on the surface away from the bottom guard plate for enhancing the strength of the protective plate.

[0017] Beneficial effects: The bottom protection device for the battery pack of the present invention is a pioneering invention. The bottom protection device of the present invention includes a bottom protection plate, which is used to protect the battery box where the battery cells are placed, to prevent the battery box from being hit or scratched by some flying stones, which may damage the battery cells, causing their performance to decline or even become unusable. The protective plate is fixedly connected by support plates arranged at both edges of the bottom protection plate, so that a gap is formed between the protective plate and the bottom protection plate. The protective plate has good rigidity and strength, and can first resist part of the external force or sharp collision objects. An airbag is placed in the gap to form a flexible protective layer to absorb and release the remaining external impact force. The airbag has the advantages of simple structure, easy installation and low manufacturing cost, and the flexible protective layer has the advantages of high cushioning and light weight.

[0018] In order to solve the above problems, a battery pack of the present invention adopts the following technical solution: A battery pack comprises a battery box for accommodating battery cells, a bottom guard device for protecting the battery box is provided below the battery box, the bottom guard device comprises a bottom guard plate fixedly connected to the bottom of the battery box, support plates are respectively provided at two opposite edge positions of the bottom guard plate, a protective plate is provided between the two support plates, and the two ends of the protective plate are respectively connected to the corresponding support plates, a gap is formed between the protective plate and the bottom guard plate, an airbag for anti-collision and buffering is placed in the gap, and a flexible protective layer is formed between the bottom guard plate and the protective plate through the airbag.

[0019] Furthermore, the two support plates are respectively provided with slide rail grooves with notches facing each other, and the two ends of the protective plate are respectively slidably connected to the corresponding slide rail grooves to form a drawer-type installation structure.

[0020] Furthermore, the two slide rail grooves are respectively provided with extension plates extending towards each other at the lower edge positions of the grooves, and each of the extension plates is respectively provided with a positioning hole, and the positioning holes are provided with pins for fixing the protective plate and the bottom guard plate.

[0021] Furthermore, sealants are respectively provided between the same ends of the two slide rail grooves to seal and form a sealed flexible protective layer.

[0022] Furthermore, the airbag is provided with elastic sealing strips at the arc edges on both sides close to the support plate.

[0023] Furthermore, the airbag is provided with multiple layers of wound fiber rubber cloth around its periphery, so that the airbag forms a rectangular shape to fit the gap between the protective plate and the bottom guard plate.

[0024] Furthermore, the airbag is provided with an air pressure sensor for monitoring the gas pressure in the airbag.

[0025] Furthermore, the airbag is provided with a plurality of air chambers, and each of the air chambers is provided with an air pressure sensor for monitoring the gas pressure in the airbag.

[0026] Furthermore, the protective plate is provided with stamping ribs on the surface away from the bottom guard plate for enhancing the strength of the protective plate.

[0027] Beneficial effects: The battery pack of the present invention is a pioneering invention. The battery pack of the present invention uses a bottom protection device, which includes a bottom protection plate. The bottom protection plate is used to protect the battery box where the battery cells are placed, to prevent the battery box from being hit or scratched by some flying stones, which may damage the battery cells, causing their performance to deteriorate or even become unusable. The protective plate is fixedly connected by support plates arranged on both edges of the bottom protection plate, so that a gap is formed between the protective plate and the bottom protection plate. The protective plate has good rigidity and strength, and can first resist part of the external force or sharp collision objects. An airbag is placed in the gap to form a flexible protective layer to absorb and release the remaining external impact force. The airbag has the advantages of simple structure, easy installation and low manufacturing cost, and the flexible protective layer has the advantages of high cushioning and light weight. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the structure decomposition of the bottom protection device for a battery pack of the present invention; Figure 2 It is a side view of the bottom protection device; Figure 3 is a schematic diagram of the bottom guard plate; Figure 4 It is the side view of the bottom guard plate; Figure 5 is a schematic diagram of an airbag; Figure 6 for Figure 5 A schematic diagram of a partial enlargement in the middle; Figure 7 Schematic diagram of the protective plate.

[0029] In the figure: 1. battery box; 2. bottom guard plate; 3. slide rail groove; 4. protective plate; 5. airbag; 6. air nozzle; 7. extension plate; 8. pin; 9. positioning hole; 10. sealing strip; 11. stamping rib; 12. support plate. DETAILED DESCRIPTION

[0030] The features and performance of the present invention are further described in detail below in conjunction with the embodiments.

[0031] The embodiments of the bottom protection device for the battery pack of the present invention are as follows: The bottom protection device for the battery pack of the present invention is designed for a bottom protection plate used to protect the battery box. The high strength and high rigidity of the protection plate with reinforcing ribs are used to block external impact, and the high cushioning and lightweight advantages of the inflated airbag are used to further buffer and absorb the remaining impact force. The two layers of flexible protection structure that cooperate with each other have a better protection effect on the battery.

[0032] As a basic solution, Figure 1-7 As shown, the bottom protection device for the battery pack of the present invention includes a bottom protection plate 2 fixedly connected to the bottom of the battery box 1, the bottom protection plate 2 is used to protect the battery box 1 where the battery cells are placed, to prevent the battery box 1 from being hit or scratched by some flying stones, which may cause damage to the battery cells or leakage of the liquid cooling plate installed on the battery box 1, and other problems, support plates 12 are respectively provided at the two opposite edge positions of the bottom protection plate 2, a protective plate 4 is provided between the two support plates 12, and the two ends of the protective plate 4 are respectively connected to the corresponding support plates 12, a gap is formed between the protective plate 4 and the bottom protection plate 2, an airbag 5 for anti-collision and buffering is placed in the gap, the airbag 5 forms a flexible protective layer between the bottom protection plate 2 and the protective plate 4, the airbag 5 as a flexible buffer structure can effectively absorb and diffuse the impact force, so as to have a better protection effect on the battery box 1, and the airbag 5 has a simple structure, is easy to install, and has a low manufacturing cost, and can be inflated through the air nozzle 6 after the airbag 5 is placed in place to avoid the risk of rupture when placed after inflation. When the protective plate 4 is subjected to external forces such as flying stones, bumps, and jolts, it can first resist a portion of the external force by using its better rigidity and strength, and at the same time prevent sharp-angled collision objects from directly piercing the airbag 5 and causing the airbag 5 to fail. Then the protective plate 4 absorbs the remaining external force and transmits it to the airbag 5, which is further absorbed by using the flexible cushioning characteristics of the airbag 5 to play a protective cushioning role.

[0033] As a preferred embodiment, the two support plates 12 are respectively provided with slide rail grooves 3 with notches facing each other, and the two ends of the protective plate 4 are respectively slidably connected with the corresponding slide rail grooves 3 to form a drawer-type installation structure. The sliding connection can quickly push the protective plate 4 along the slide rail groove 3. This structure is simple and easy to install, which not only saves manpower but also improves production efficiency. In other embodiments, the slide rail groove 3 is not provided, and the protective plate 4 is directly fixedly connected to the support plate 12 by gluing or welding. Although the convenience is not high, it can also achieve the effect of connection.

[0034] As a preferred embodiment, Figure 3-4As shown, the two slide rail grooves 3 are respectively provided with extension plates 7 extending towards each other at the lower edge position of the groove, and the extension plates 7 can support the protective plate 4. Each extension plate 7 is provided with a positioning hole 9, and the positioning hole 9 is provided with a pin 8 for fixing the protective plate 4 and the bottom guard plate 2, which can prevent the protective plate 4 from moving left and right along the slide rail groove 3 during the driving of the car. The pin 8 has strong adaptability and can adapt to the connection of plates of different thicknesses, and the pin 8 connection operation is simple, and the connection is stable and reliable. In other embodiments, rivets or adhesives can be used to prevent the movement of the protective plate 4.

[0035] As a preferred embodiment, sealants are respectively provided between the same ends of the two slide rail grooves 3 to seal and form a sealed flexible protective layer, which is used to meet the sealing requirements of the front and rear of the bottom protection device to prevent mud, sand, flying stones, foreign objects, etc. from entering and damaging the airbag 5. The sealant has excellent sealing performance, can tightly adhere to various materials and form a firm protective film, and can effectively block the penetration of foreign objects such as moisture or dust, ensuring the dryness and cleanliness of the inside of the sealed object. Moreover, the sealant is easy to use, does not require complicated equipment or tools, and has a low purchase cost. In other embodiments, materials with better sealing properties such as rubber sealing covers or plastic sealing covers can be selected, and the flexible protective layer can also be sealed front and back.

[0036] As a preferred embodiment, Figure 5-6 As shown, the airbag 5 is provided with elastic sealing strips 10 at the arc edges on both sides near the support plate 12. When the airbag 5 is inflated, the sealing strip 10 spreads around, and can further fill the gap between the protective plate 4 and the bottom guard plate 2 near the slide rail groove 3, so that mud and sand cannot be stored to reduce the corrosion of the relative box body by mud and sand.

[0037] As a preferred embodiment, the airbag 5 is provided with multiple layers of fiber rubber cloth wrapped around it, so that the airbag 5 forms a rectangular shape to adapt to the gap between the protective plate 4 and the bottom guard plate 2. The fiber rubber cloth combines the elasticity of rubber with the strength and wear resistance of fiber, so it has high tensile strength and tear strength. This enables the fiber rubber cloth to withstand large external forces and is not easy to be damaged or broken, so as to better protect the airbag 5 from being damaged. In addition, the fiber rubber cloth also has excellent sealing performance and can fit tightly on various surfaces. The plasticity of the fiber rubber cloth can be used to set the airbag 5 to a rectangular shape that adapts to the gap between the protective plate 4 and the bottom guard plate 2, so as to better fill the gap and play a better protective role. In other embodiments, elastic fabrics such as nylon or polyester fibers can be selected, which also have high strength and wear resistance, but their plasticity is weaker than that of the fiber rubber cloth in this preferred embodiment, but they can also protect the airbag 5.

[0038] As a preferred embodiment, the airbag 5 is provided with an air pressure sensor for monitoring the gas pressure in the airbag 5. The use of the air pressure sensor for monitoring has the advantages of high-precision measurement, real-time monitoring and intelligence. When the pressure value is lower than a certain set value, a signal will be transmitted to the driver, so that the driver can stop and check in time. In other embodiments, a pressure gauge can be used to measure the pressure in the airbag 5. The driver is required to check whether the airbag 5 is damaged or leaking after a collision. Although it is not as intelligent as the preferred embodiment, it can also achieve the effect of measuring pressure.

[0039] As a preferred embodiment, the airbag 5 is provided with a plurality of air chambers, each of which is provided with an air pressure sensor for monitoring the gas pressure in the airbag 5. The plurality of air chambers can average the pressure distribution on the airbag 5, thereby improving the protective effect of the airbag 5. The air pressure sensors provided in each air chamber can quickly locate the damaged position, and can be repaired in time to avoid causing greater risks. In addition, the plurality of air chambers can be provided so that when the airbag 5 is damaged, only a few of the air chambers will leak, and the remaining air chambers can continue to protect the battery, leaving the driver with sufficient time for inspection and repair, thereby avoiding the battery losing protection and increasing the risk of being damaged when the entire airbag 5 is ruptured.

[0040] As a preferred embodiment, Figure 7 As shown, the protective plate 4 is provided with a stamped rib 11 on the surface away from the bottom guard plate 2 for enhancing the strength of the protective plate 4. The provision of the stamped rib 11 can enhance the strength and rigidity of the protective plate 4 to a certain extent, so that it can more effectively resist deformation or damage when subjected to impact. In addition, it can also disperse stress and reduce stress concentration in local areas, thereby reducing the risk of fatigue and damage of the protective plate 4, thereby enhancing the strength of the bottom guard device and extending its service life. In other embodiments, a protective plate of the same size can be arranged under the protective plate 4, which can also extend the service life of the protective plate 4. Compared with the lightweight arrangement of the reinforcing ribs in the preferred embodiment, although the weight of an entire protective plate is increased, the same purpose can be achieved.

[0041] The use process of the bottom protection device for the battery pack of the present invention is as follows: Figure 1As shown, the protective plate 4 is pushed into the slide rail groove 3 provided on the bottom guard plate 2 to form a gap, and is fixedly connected by a pin 8 to prevent it from moving. The airbag 5 is placed in the gap and can be inflated through the air nozzle 6. The inflated airbag 5 forms a flexible protective layer in the gap. When an external force acts on the protective plate 4, the protective plate 4 first resists a part of the force and prevents sharp collision objects from directly acting on the airbag 5, causing the airbag 5 to fail. Then the protective plate 4 transmits the remaining force to the airbag 5, and the airbag 5 is used to further absorb the collision force. At this time, most of the external impact energy has been basically consumed. When the airbag 5 is damaged and leaks due to excessive squeezing, the air pressure sensor provided on one side of the airbag 5 will detect that the pressure is lower than a set value and will promptly transmit a signal to the driver, so that the driver can stop the car in time for inspection and further processing.

[0042] The embodiments of the battery pack of the present invention are: A battery pack includes a battery box 1 for accommodating battery cells, wherein a bottom protection device for protecting the battery box 1 is provided below the battery box 1, wherein an embodiment of the bottom protection device has been described above and will not be repeated here.

[0043] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. The patent protection scope of the present invention shall be based on the claims. All equivalent structural changes made using the contents of the description and drawings of the present invention should also be included in the protection scope of the present invention.

Claims

1. A bottom protection device for a battery pack, comprising a bottom protection plate fixedly connected to the bottom of a battery box, characterized in that: Support plates are respectively provided at the two opposite edge positions of the bottom guard plate, a protective plate is provided between the two support plates, and both ends of the protective plate are respectively connected to the corresponding support plates, a gap is formed between the protective plate and the bottom guard plate, an airbag for anti-collision and buffering is placed in the gap, and a flexible protective layer is formed between the bottom guard plate and the protective plate through the airbag.

2. The bottom protection device for a battery pack according to claim 1, characterized in that: The two support plates are respectively provided with slide rail grooves with notches facing each other, and the two ends of the protective plate are respectively slidably connected with the corresponding slide rail grooves to form a drawer-type installation structure.

3. The bottom protection device for a battery pack according to claim 2, characterized in that: The two slide rail grooves are respectively provided with extension plates extending towards each other at the lower edge positions of the groove openings, and each extension plate is respectively provided with a positioning hole, and a pin for fixing and connecting the protective plate and the bottom guard plate is provided in the positioning hole.

4. The bottom protection device for a battery pack according to claim 2, characterized in that: Sealant is provided between the same ends of the two slide rail grooves to seal and form a sealed flexible protective layer.

5. The bottom protection device for a battery pack according to claim 1, characterized in that: The airbag is provided with elastic sealing strips at the arc edges on both sides close to the support plate.

6. The bottom protection device for a battery pack according to claim 1 or 5, characterized in that: The airbag is provided with multiple layers of wound fiber rubber cloth around its periphery, so that the airbag forms a rectangular shape to fit the gap between the protective plate and the bottom guard plate.

7. The bottom protection device for a battery pack according to claim 1, characterized in that: The airbag is provided with an air pressure sensor for monitoring the gas pressure in the airbag.

8. The bottom protection device for a battery pack according to claim 7, characterized in that: The airbag is provided with a plurality of air chambers, and each of the air chambers is provided with an air pressure sensor for monitoring the gas pressure in the airbag.

9. The bottom protection device for a battery pack according to claim 1, characterized in that: The protective plate is provided with stamping ribs on the surface away from the bottom guard plate for enhancing the strength of the protective plate.

10. A battery pack, comprising a battery box for placing battery cells, wherein a bottom protection device for protecting the battery box is provided below the battery box, characterized in that: The bottom protection device is the bottom protection device described in any one of claims 1 to 9.

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