Battery pack bottom protection plate structure, battery pack and vehicle

Abstract

The utility model discloses a battery pack bottom protection plate structure, a battery pack and a vehicle. The battery pack bottom protection plate structure comprises an anti-impact layer, an energy absorption layer, a rigid layer and a heat insulation buffer layer which are sequentially arranged in a stacked mode, and when the bottom protection plate structure is applied to a battery pack, the heat insulation buffer layer is located on the side close to a battery cell of the battery pack. The battery pack bottom protection plate provided by the utility model meets the bottom protection requirement of the battery pack, meets the sealing performance of the bottom of the battery pack, reduces the overall weight of the battery pack, and improves the overall energy density of the battery pack.

Description

Technical Field

[0001] The utility model relates to the technical field of electric vehicles, and in particular to a battery pack bottom guard plate structure, a battery pack and a vehicle. Background Art

[0002] In the prior art, the bottom of the battery pack is provided with a bottom guard plate to prevent the bottom of the battery pack from being bumped and damaging the battery cells in the battery pack, thereby avoiding safety accidents that may cause fires due to thermal runaway of damaged battery cells. The existing bottom guard plates of battery packs include metal bottom guard plates, which are generally steel plates or aluminum alloy profile plates. In order to ensure sufficient protection capabilities, the metal bottom guard plate needs to have sufficient thickness, which will affect the overall weight of the battery pack. There are also composite bottom guard plates with a multi-material stacking design to reduce the weight of the bottom guard plate, but this type of bottom guard plate often cannot balance the protection performance of each layer in the bottom guard plate well, and the protection reliability of the bottom guard plate structure is insufficient. Utility Model Content

[0003] The purpose of the utility model is to provide a battery pack bottom guard plate structure, which can at least solve the above-mentioned technical problems in the prior art to a certain extent and improve the reliability of the battery pack.

[0004] According to the battery pack bottom guard plate structure of the embodiment of the utility model, it includes an impact-resistant layer, an energy-absorbing layer, a rigid layer and a thermal insulation buffer layer stacked in sequence. When the bottom guard plate structure is applied to the battery pack, the thermal insulation buffer layer is located on the side close to the battery cell of the battery pack.

[0005] Furthermore, the rigid layer has a first groove facing the thermal insulation buffer layer, the four sides of the first groove have flange edges, the bottom surface of the first groove has at least one second groove facing the impact-resistant layer, and the energy absorption layer is arranged in the second groove.

[0006] Furthermore, the bottom surface of the first groove has three second grooves, and there are retaining ribs between adjacent second grooves. The positions of the three second grooves are opposite to the positions of the battery cells arranged in the battery pack.

[0007] According to some embodiments of the present invention, the impact-resistant layer includes a fiber-reinforced composite material layer and a PVC layer. The fiber-reinforced composite material layer is arranged on the surface of the energy-absorbing layer, and the PVC layer is arranged on the surface of the rib.

[0008] According to some embodiments of the present invention, the energy absorbing layer includes at least one of an MPP foamed board, a rigid polyurethane board, a PP honeycomb core board, a foamed aluminum board and a phenolic resin foamed board.

[0009] According to some embodiments of the present invention, the rigid layer is a steel plate or an aluminum alloy plate.

[0010] According to some embodiments of the present invention, the thermal insulation buffer layer is made of MPP foam board material.

[0011] According to some embodiments of the utility model, the thickness of the heat insulating buffer layer is 0.5mm-3mm, the thickness of the rigid layer is 0.5mm-3mm, the thickness of the energy absorbing layer is 4mm-10mm, and the thickness of the impact resistant layer is 0.5mm-1.5mm.

[0012] The utility model also proposes a battery pack having the battery pack bottom guard plate structure.

[0013] The utility model also provides a vehicle with the battery pack.

[0014] Compared with the prior art, the utility model has the following advantages:

[0015] The battery pack bottom guard plate structure provided in the embodiment of the utility model meets the protection requirements of the battery pack bottom while ensuring the sealing of the battery pack bottom, reducing the overall weight of the battery pack and increasing the overall energy density of the battery pack. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of a battery pack bottom guard plate structure provided by an embodiment of the utility model;

[0017] Figure 2 It is an exploded schematic diagram of a partial structure of a battery pack box provided by an embodiment of the utility model;

[0018] Figure 3 This is a cross-sectional schematic diagram of a partial box structure of a battery pack provided by an embodiment of the utility model

[0019] Notes on the attached drawings:

[0020] 100. Bottom guard plate; 1. Impact-resistant layer; 2. Energy-absorbing layer; 3. Rigid layer; 31. First groove; 32. Flange edge; 33. Second groove; 34. Rebar; 4. Thermal insulation buffer layer; 5. Frame; 6. Liquid cooling plate. DETAILED DESCRIPTION

[0021] Many specific details are described in the following description to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art can make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific implementation disclosed below.

[0022] The utility model embodiment firstly discloses a battery pack bottom guard plate structure, which is used to protect the bottom of the battery pack to prevent the bottom of the battery pack from being damaged due to collision, thereby causing damage to the battery cells or battery cell components inside the battery pack.

[0023] See also Figure 1-3 As shown, the utility model provides an embodiment in which the battery pack bottom guard plate structure 100 includes an anti-impact layer 1, an energy absorption layer 2, a rigid layer 3 and a heat-insulating buffer layer 4 which are stacked in sequence. After the bottom guard plate structure 100 is applied to the battery pack, the heat-insulating buffer layer 4 is located on the side close to the battery cell of the battery pack, the anti-impact layer 1 is located on the side away from the battery cell of the battery pack, the energy absorption layer 2 and the rigid layer 3 are arranged between the anti-impact layer 1 and the heat-insulating buffer 4, wherein the rigid layer 3 is close to the heat-insulating buffer 4, and the energy absorption layer 2 is close to the anti-impact layer 1.

[0024] After the battery pack is installed on the vehicle, the impact-resistant layer 1 faces the ground. The impact-resistant layer 1 has a suitable hardness and can resist the impact of gravel and the like, so as to keep the appearance of the bottom surface of the battery pack smooth.

[0025] When the bottom of the battery pack is hit more seriously, the impact-resistant layer 1 cannot resist the energy impact of the collision, and the impact energy is transferred to the energy-absorbing layer 2. The energy-absorbing layer 2 can absorb the impact energy by deformation and collapse, thereby reducing or avoiding the impact energy from being further transferred to the inside of the battery pack and damaging the battery cells inside the battery pack.

[0026] The rigid layer 3 has appropriate rigidity. When the energy-absorbing layer 2 cannot completely resist the impact energy of the collision, the rigid layer 3 further plays a protective role. Under the protection of the impact-resistant layer 1 and the energy-absorbing layer 2, most of the impact energy has been absorbed, and the unabsorbed part of the impact energy is transmitted to the rigid layer 3. Because the rigid layer 3 has a certain rigidity and is not prone to plastic deformation, it can resist the unabsorbed part of the impact energy, thereby preventing damage to the battery cells in the battery pack, and further avoiding safety problems caused by thermal runaway due to battery cell damage.

[0027] The heat-insulating buffer layer 4 is close to the battery cell and plays a role of heat insulation and buffering. On the one hand, it reduces or avoids the heat loss in the bottom area of ​​the battery pack and prevents the temperature in the bottom area of ​​the battery pack from being uneven with that in other areas. On the other hand, it buffers the elastic deformation that may occur in the rigid layer 3 and provides ultimate protection for the battery cells in the battery pack.

[0028] In the above embodiment, the elastic modulus of the energy absorbing layer 2 is K1, the elastic modulus of the rigid layer 3 is K2, and the elastic modulus of the heat insulating buffer layer 4 is K3, wherein K2>K1>K3. The bottom guard plate structure in this embodiment is designed by arranging materials with different elastic moduli in layers, so that when the battery pack encounters a bump, the battery cells in the battery pack are better protected from damage.

[0029] In the above embodiment, the impact-resistant layer 1 is a fiber-reinforced composite material, such as a glass fiber-reinforced composite material, a carbon fiber-reinforced composite material or an aramid fiber-reinforced composite material. The energy-absorbing layer 2 is at least one of an MPP foam material, a rigid polyurethane material, a PP honeycomb core material, a foamed aluminum material, and a phenolic resin foam material. The rigid layer 3 is a metal plate, such as a steel plate or an aluminum alloy plate. The heat-insulating buffer layer 4 is an MPP foam material.

[0030] In one embodiment of the utility model, the rigid layer 3 is a rigid plate, including a first groove 31, which can be obtained by stamping. A flange edge 32 is formed around the first groove 31, and the opening of the first groove 31 faces the heat-insulating buffer layer 4. The flange edge 32 is used for sealing and docking with the frame of the battery pack. The bottom surface of the first groove 31 has at least one second groove 33, which can also be obtained by stamping. The opening of the second groove 33 faces the impact-resistant layer 1. An energy-absorbing layer 2 is arranged in the second groove 33, and the energy-absorbing layer 2 fills the second groove 33. The position of the second groove 32 corresponds to the position of the battery cell in the battery pack, that is, the second groove 32 is located below the battery cell in the battery pack. The impact-resistant layer 1 is arranged on the surface of the energy-absorbing layer 2, covering the entire energy-absorbing layer 2.

[0031] Furthermore, in the aforementioned embodiment, the number of the second grooves 33 is three, and the three second grooves 33 are arranged along the length direction or the width direction of the battery pack. A rib 34 is formed between two adjacent second grooves 33, and the widths of the three second grooves 33 along the length direction of the battery pack are the same, or may be different according to actual needs. The arrangement of the first groove 31 and the second groove 33 can improve the overall rigidity of the rigid layer 3, thereby improving the protective performance of the entire bottom guard plate 100. Energy absorption layers 2 are respectively arranged in the three second grooves 33, and the three energy absorption layers 2 respectively protect the battery cells in the corresponding areas in the battery pack. The impact received by the energy absorption layers 2 in different second grooves 33 will not be transmitted to other second grooves 33.

[0032] Further, in the aforementioned embodiment, energy absorbing layers 2 are respectively provided in the three second grooves 33. The impact resistant layer 1 is provided on the surface of the energy absorbing layer 2 and the surface of the retaining rib 34. The impact resistant layer 1 includes a fiber reinforced composite material layer and a PVC layer, wherein the fiber reinforced composite material layer covers the surface of the energy absorbing layer 2, and the PVC layer covers the surface of the retaining rib 34. The impact resistant layer 1 of the fiber reinforced composite material has a certain hardness, can resist slight impact or scratching of gravel, etc., and protect the appearance of the bottom surface of the battery pack.

[0033] In one embodiment of the utility model, the thickness of the heat insulating buffer layer 4 is 0.5mm-3mm, the thickness of the rigid layer 3 is 0.5mm-3mm, the thickness of the energy absorbing layer 2 is 4mm-10mm, and the thickness of the impact resistant layer 1 is 0.5mm-1.5mm. By setting the thickness of each different material layer, the bottom guard plate structure 100 provided by the utility model can reduce the weight of the bottom guard plate structure 100 on the basis of providing sufficient protection performance, reduce the influence of the bottom guard plate structure on the weight of the entire battery pack, and improve the overall energy density of the battery pack.

[0034] The utility model also provides a battery pack, which includes a frame 5 and a liquid cooling plate 6 sealed and connected to the bottom of the frame, and a bottom guard plate structure 100 of any of the above embodiments, wherein the flange edge 32 of the rigid layer 3 of the bottom guard plate structure 100 is sealed and docked with the bottom surface of the frame 5, sealing and protecting the bottom surface of the battery pack. The heat insulating buffer layer 4 of the bottom guard plate structure 100 covers the liquid cooling plate 6, ensuring that the entire liquid cooling plate 6 is cooled evenly, and ensuring that the temperature distribution of the battery cells in the battery pack meets the requirements.

[0035] The utility model also provides a vehicle, comprising the battery pack of the aforementioned embodiment.

[0036] The battery pack bottom guard plate structure provided by the utility model can at least achieve the following beneficial effects: meet the protection requirements of the battery pack bottom, and can simultaneously meet the sealing, rigid protection and fire protection requirements of the battery pack bottom.

[0037] It should be noted that although the utility model is disclosed as above in the form of a preferred embodiment, it is not intended to limit the utility model. Any technical personnel in this field may make possible changes and modifications without departing from the spirit and scope of the utility model. Therefore, the scope of protection of the utility model shall be based on the scope defined by the claims of the utility model.

Claims

1. A battery pack bottom guard plate structure, characterized in that: It includes an impact-resistant layer, an energy-absorbing layer, a rigid layer and a heat-insulating buffer layer which are stacked in sequence. When the battery pack bottom guard plate structure is applied to a battery pack, the heat-insulating buffer layer is located on a side close to the battery cell of the battery pack.

2. The battery pack bottom guard plate structure according to claim 1, characterized in that: The rigid layer has a first groove facing the heat-insulating buffer layer, the four sides of the first groove have flange edges, the bottom surface of the first groove has at least one second groove facing the impact-resistant layer, and the energy-absorbing layer is arranged in the second groove.

3. The battery pack bottom guard plate structure according to claim 2, characterized in that: The bottom surface of the first groove has three second grooves, and there are retaining ribs between adjacent second grooves. The positions of the three second grooves are opposite to the positions of the battery cells arranged in the battery pack.

4. The battery pack bottom guard plate structure according to claim 3, characterized in that: The impact-resistant layer comprises a fiber-reinforced composite material layer and a PVC layer. The fiber-reinforced composite material layer is arranged on the surface of the energy-absorbing layer, and the PVC layer is arranged on the surface of the retaining rib.

5. The battery pack bottom guard plate structure according to claim 3, characterized in that: The energy absorbing layer comprises at least one of an MPP foaming plate, a rigid polyurethane plate, a PP honeycomb core plate, a foamed aluminum plate and a phenolic resin foaming plate.

6. The battery pack bottom guard plate structure according to claim 3, characterized in that: The rigid layer is a steel plate or an aluminum alloy plate.

7. The battery pack bottom guard plate structure according to claim 3, characterized in that: The heat insulation buffer layer is made of MPP foam board material.

8. The battery pack bottom guard plate structure according to claim 1, characterized in that: The thickness of the heat-insulating buffer layer is 0.5 mm-3 mm, the thickness of the rigid layer is 0.5 mm-3 mm, the thickness of the energy-absorbing layer is 4 mm-10 mm, and the thickness of the impact-resistant layer is 0.5 mm-1.5 mm.

9. A battery pack, characterized in that: The battery pack has a bottom guard plate structure according to any one of claims 1-8.

10. A vehicle, characterized in that: The vehicle has a battery pack according to claim 9 or a battery pack bottom guard plate according to any one of claims 1-8.

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