A honeycomb sandwich structure battery pack lower case capable of improving battery module collision safety

Abstract

The utility model discloses a honeycomb sandwich structure battery pack lower shell that can improve battery module collision safety, the left and right sides of lower shell are composed of bionic honeycomb sandwich structure, and the honeycomb structure includes aluminum honeycomb core, CFRP skin and elastomer SBR interlayer of skin, and the front and back and the downside are composed of solid aluminum plate of equal thickness, and each part is mutually cemented to form, the length of lower shell is 1908mm, the width is 1110mm, the height is 238mm, and the thickness is 2.6mm, the utility model discloses a novel battery pack lower shell that can improve battery module collision safety by utilizing bionic honeycomb sandwich structure design with excellent energy absorption characteristics and crashworthiness, when being impacted, elastomer SBR improves the impact toughness of CFRP skin, reduces the deformation damage of CFRP, and aluminum honeycomb core absorbs most of the collision energy, so as to reduce the collision energy transmitted to the battery module, improves the collision safety of battery module, and the novel battery pack lower shell has the characteristics of light weight, the battery pack lower shell disclosed by the utility model can significantly improve safety, and has wide application prospect in the field of battery pack design.

Description

Technical Field

[0001] This utility model relates to a honeycomb sandwich structure battery pack lower shell, specifically to a method that replaces the solid aluminum plates on the left and right sides of the original battery pack lower shell with a biomimetic honeycomb sandwich structure. Background Technology

[0002] In recent years, numerous reports have documented cases of new energy vehicles catching fire after traffic accidents. The cause is often severe deformation of the lower casing of the power battery pack, puncturing the battery module, leading to electrolyte leakage and subsequent fire. Therefore, it is necessary to address the insufficient collision safety of battery modules. Currently, improving the collision safety of battery modules is a major concern for automakers and consumers. The most common and efficient method is to enhance the impact resistance of the lower casing of the battery pack. Since new energy vehicles often pursue extreme lightweight design, improving impact resistance without increasing weight or even reducing weight is a design principle for automakers. Biomimetic honeycomb sandwich structures, due to their lightweight and high strength-to-weight ratio, are well-suited for designing lower casings of battery packs. Therefore, inventing a honeycomb sandwich structure lower casing for battery modules that can improve collision safety while achieving lightweight design would have significant practical engineering implications. Traditional aluminum biomimetic honeycomb sandwich structures have poor impact resistance. This invention uses carbon fiber reinforced composite material to manufacture the skin, and simultaneously bonds an elastomer SBR sandwich layer between two carbon fiber plates of the skin to form a biomimetic honeycomb sandwich structure. This structure is then used to design the lower shell of the battery pack to improve the impact resistance and energy absorption characteristics of the lower shell, thereby enhancing the collision safety of the battery module. Summary of the Invention

[0003] The purpose of this invention is to provide a honeycomb sandwich structure battery pack lower shell that can improve the collision safety of battery modules. Taking the original solid aluminum plate battery pack lower shell as the research object, this invention replaces the original solid aluminum plate with a biomimetic honeycomb sandwich structure and improves the impact toughness of CFRP by using the elastomer SBR, thereby improving the impact resistance of the biomimetic honeycomb sandwich structure. At the same time, it improves the impact resistance and energy absorption characteristics of the battery pack lower shell, thus improving the collision safety of the battery module.

[0004] To achieve the above objectives, this utility model employs the following technical solution:

[0005] A honeycomb sandwich structure battery pack lower casing that improves the collision safety of battery modules is characterized by the following: a biomimetic honeycomb sandwich structure is bonded to an aluminum plate of equal thickness using industrial adhesive; adjacent honeycomb cells in the aluminum honeycomb core of the biomimetic honeycomb sandwich structure share the same honeycomb wall, and the two honeycomb cells are closely arranged in a 60° tangent configuration; the CFRP skin is woven from two carbon fiber plates with a layup angle of 0° and two carbon fiber plates with a layup angle of 90°; the high-toughness CFRP skin of the biomimetic honeycomb sandwich structure contains an elastomer SBR interlayer between the two carbon fiber plates; the bonded honeycomb sandwich structure has high impact resistance and high energy absorption characteristics; and the battery pack lower casing designed using the biomimetic honeycomb sandwich structure has high impact resistance and energy absorption characteristics.

[0006] Furthermore, the overall thickness of the biomimetic honeycomb sandwich structure is the same as the thickness of the original solid aluminum plate under the battery pack casing.

[0007] Furthermore, the battery module is installed inside the lower casing of the battery pack, which is formed by bonding the biomimetic honeycomb sandwich structure and the solid aluminum plate together.

[0008] Furthermore, adjacent cells of the honeycomb core share the same honeycomb wall, and the two cells are closely arranged in a 60° tangent configuration.

[0009] Furthermore, the high-toughness CFRP skin contains an elastomer SBR interlayer between the two carbon fiber plates.

[0010] Furthermore, the CFRP skin, the SBR elastomer, and the internal aluminum honeycomb core are all bonded together.

[0011] Furthermore, the solid aluminum plate is made of aluminum alloy 6061, the skin is made of carbon fiber reinforced composite material, the honeycomb core is made of aluminum alloy 6061, and the elastomer interlayer is made of rubber material.

[0012] This invention relates to a honeycomb sandwich structure battery pack lower housing that improves the collision safety of battery modules. Based on the existing power battery pack lower housing, and with the goal of improving the collision safety of battery modules, it replaces the original solid aluminum plate with a biomimetic honeycomb sandwich structure. Simultaneously, it uses carbon fiber reinforced material to manufacture the skin of the biomimetic honeycomb sandwich structure, and adds an elastomer SBR interlayer between the two carbon fiber plates of the CFRP skin to improve the impact toughness of the CFRP skin, thus solving the problem of insufficient impact resistance of the biomimetic honeycomb sandwich structure. By replacing the original solid aluminum plate with a biomimetic honeycomb sandwich structure, the impact resistance and energy absorption characteristics of the battery pack lower housing are improved, reducing damage to the battery module and improving the collision safety of the battery module. At the same time, it reduces the weight of the battery pack lower housing, achieving a lightweight design.

[0013] This utility model has a relatively simple structure and is easy to manufacture, but it significantly improves the collision safety of the battery module. By replacing the solid aluminum plate with a biomimetic honeycomb sandwich structure on the basis of the original power battery pack lower shell, the impact resistance and energy absorption characteristics of the battery pack lower shell can be improved, protecting the battery module and preventing electrolyte leakage after a collision from causing a fire that endangers the life and property of the occupants. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the geometric model of the original battery pack lower casing mentioned in this utility model;

[0015] Figure 1 In the middle: 1. Battery cell, 2. Battery module, 3. Mounting bracket, 4. Lower housing, 5. Control module;

[0016] Figure 2 This is a schematic diagram of the biomimetic honeycomb sandwich structure designed in this utility model;

[0017] Figure 2 In the middle: 1. Carbon fiber plate, 2. SBR elastomer, 3. Aluminum honeycomb core, 4. Upper skin, 5. Lower skin, 6. Bionic honeycomb sandwich structure;

[0018] Figure 3 This is a schematic diagram of the geometric model of the lower shell of the biomimetic honeycomb sandwich structure battery pack designed in this utility model;

[0019] Figure 3 In Chinese: 1. Bionic honeycomb sandwich structure, 2. Bionic honeycomb sandwich structure, 3. Solid aluminum plate, 4. Solid aluminum plate;

[0020] Figure 4 The simulated displacement-time curves are for the two types of lower housings of the battery packs and the No. 30 battery module in Example 1.

[0021] Figure 4 (a) Comparison of the impact resistance of the original battery pack lower casing and the biomimetic honeycomb sandwich structure battery pack lower casing; (b) Comparison of the collision safety of battery module No. 30.

[0022] Figure 5 The simulated displacement-time curves are for the two types of battery pack lower shells and the No. 30 battery module in Example 2;

[0023] Figure 5 (a) Comparison of the impact resistance of the original battery pack lower casing and the biomimetic honeycomb sandwich structure battery pack lower casing; (b) Comparison of the collision safety of battery module No. 30. Detailed Implementation

[0024] The present invention will now be further described in conjunction with the accompanying drawings and embodiments:

[0025] Example 1

[0026] exist Figure 1 The original battery pack lower casing, in its structure, includes battery cells 1, battery modules 2, mounting brackets 3, lower casing 4, and control module 5. The lower casing is 1908 mm long, 1110 mm wide, 238 mm high, and 2.6 mm thick, containing 32 battery modules. Figure 2 In the biomimetic honeycomb sandwich structure 6, the upper skin 4 comprises two carbon fiber plates 1 and an elastomer SBR sandwich layer 2. The carbon fiber plates 1, aluminum honeycomb core 3, and elastomer SBR sandwich layer 2 are all bonded together with industrial adhesive. The two honeycomb units of the aluminum honeycomb core 3 are tightly arranged at a 60° tangency. Furthermore, two adjacent honeycomb units share the same honeycomb wall. Considering practical manufacturing and weight issues, the length and width of the biomimetic honeycomb core after arraying in the X and Y axes can be smaller than the length and width of the skin. The lower skin 5 of the biomimetic honeycomb sandwich structure has the same structure as the upper skin 4. Figure 3 Among them, a honeycomb sandwich structure battery pack lower shell that can improve the collision safety of battery modules includes two biomimetic honeycomb sandwich structures 1 and 2, two solid aluminum plates 3 and 4 of equal thickness, and the rest of the structure is the same as the original battery pack lower shell.

[0027] The lower casing of the battery pack features a honeycomb sandwich structure that enhances the collision safety of battery modules. The biomimetic honeycomb sandwich structure uses a carbon fiber reinforced composite skin, a 6061 aluminum alloy core, and a rubber elastomer interlayer. All components are bonded together using adhesive. The high-toughness CFRP skin of the biomimetic honeycomb sandwich structure is 0.35 mm thick, the carbon fiber plate 1 of the upper skin is 0.075 mm thick, the elastomer SBR interlayer 2 is 0.20 mm thick, the aluminum honeycomb core 3 is 1.9 mm thick, and the thickness of the industrial adhesive is negligible. The pore size ρ of the honeycomb unit is 2.4 mm, and the wall thickness t is 0.06 mm. The biomimetic honeycomb sandwich structure is 50 mm long and wide, and 2.6 mm high. The addition of SBR elastomer between the two carbon fiber plates of the skin improves the impact toughness of the skin, thereby enhancing the impact resistance of the biomimetic honeycomb sandwich structure. To facilitate simulation calculations, the length, width, and height of the original battery pack lower casing were scaled down proportionally. The scaled-down honeycomb sandwich structure battery pack lower casing has a length of 95.4 mm, a width of 55.5 mm, and a height of 11.9 mm. The thickness, however, should not be scaled down proportionally and should remain at the original 2.6 mm. Using LS-DYNA software, finite element models of the side column collision of the two battery pack lower casings were established under the explicit analysis model. The collision velocity was set to 32 km / h. The displacement-time curves of the lower casing after the collision and the displacement-time curve of the No. 30 battery module with the largest deformation were exported. The simulation results are as follows. Figure 4 As shown, the maximum deformation of the honeycomb sandwich structure battery pack shell is reduced by 37.14% compared to the original battery pack lower shell, and the maximum deformation of the No. 30 battery module is reduced by 70.65%. At the same time, the maximum deformation of the battery module is reduced to below the safety threshold. The impact resistance and protection effect of the honeycomb sandwich structure battery pack lower shell are significantly better than the original battery pack lower shell, thus improving the collision safety of the battery module.

[0028] Example 2

[0029] The geometric model of the lower casing of the honeycomb sandwich structure battery pack is as follows: Figure 3 As shown, the biomimetic honeycomb sandwich structure 6 has a skin made of carbon fiber reinforced composite material, a honeycomb core made of aluminum alloy 6061, and an elastomer sandwich layer made of rubber. All components are bonded together using adhesive. The CFRP skin thickness is 0.35 mm, the carbon fiber plate 1 of the skin is 0.175 mm thick, there is no elastomer SBR sandwich layer 2, the aluminum honeycomb core 3 is 1.9 mm thick, and the thickness of the industrial adhesive is negligible. The pore size ρ of the honeycomb unit is 2.4 mm, and the wall thickness t is 0.06 mm. The length and width of the biomimetic honeycomb sandwich structure are both 50 mm, and the height is 2.6 mm. To facilitate simulation calculations, the length, width, and height of the original battery pack lower shell are proportionally reduced. The reduced honeycomb sandwich structure battery pack lower shell has a length of 95.4 mm, a width of 55.5 mm, and a height of 11.9 mm. The thickness cannot be proportionally reduced and should remain at the original 2.6 mm. The side-pillar collision simulation performed in LS-DYNA software is the same as in Example 1, and the simulation results are as follows. Figure 5 As shown, the maximum deformation of the honeycomb sandwich structure battery pack outer shell is reduced by 27.45% compared to the maximum deformation of the original battery pack lower shell, and the maximum deformation of the No. 30 battery module is reduced by 67.39%. Although the maximum deformation of the No. 30 battery module is significantly reduced, it still slightly exceeds the safety threshold for deformation. The collision safety of the battery module is improved, but it still faces a small probability of electrolyte leakage causing a fire. The collision safety of the battery module in Example 2 is inferior to that in Example 1. Therefore, Example 1 can be preferred in practical engineering.

[0030] In addition, the selection of materials for the biomimetic honeycomb sandwich structure, such as the thickness of the carbon fiber plate 1 of the skin, the thickness of the SBR elastomer sandwich 2, and the thickness, pore size, and wall thickness of the aluminum honeycomb core 3, can all be selected according to the actual situation.

[0031] The above description is only a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any transformation or substitution that can be conceived without creative effort should be included within the protection scope of this utility model.

Claims

1. A honeycomb sandwich structure battery pack lower casing that can improve the collision safety of battery modules, characterized in that, Because the battery pack lacks collision protection and energy absorption devices, side impacts typically cause greater damage compared to other types of collisions. Therefore, to save manufacturing costs and reduce manufacturing difficulty, only two sides of the outer shell utilize a biomimetic honeycomb structure, while the remaining sides retain the original solid aluminum plates of uniform thickness. The biomimetic honeycomb sandwich structure consists of an aluminum honeycomb core, a CFRP skin, and an elastomer SBR interlayer bonded together. The aluminum honeycomb core is formed by filling and arranging regular hexagonal honeycomb cells in the X and Y axis directions. The CFRP skin is woven together from two carbon fiber plates with a layup angle of 0° and two carbon fiber plates with a layup angle of 90°. The CFRP skin is bonded to the upper and lower surfaces of the honeycomb core. The elastomer SBR interlayer is located between the two carbon fiber plates of the CFRP skin, forming a high-toughness CFRP skin. The honeycomb sandwich structure formed by the high-toughness CFRP skin and the honeycomb core has high impact resistance and high energy absorption characteristics. The lower shell of the battery pack designed with the biomimetic honeycomb sandwich structure can reduce the damage to the battery module after a collision, thus improving collision safety.

2. The honeycomb sandwich structure battery pack lower housing according to claim 1, which can improve the collision safety of battery modules, is characterized in that, The biomimetic honeycomb sandwich structure is bonded to an aluminum plate of equal thickness using industrial adhesive.

3. The honeycomb sandwich structure battery pack lower housing according to claim 1, which can improve the collision safety of battery modules, is characterized in that, The aluminum honeycomb core of the biomimetic honeycomb sandwich structure has two adjacent honeycomb cells sharing the same honeycomb wall, and the two honeycomb cells are closely arranged in a 60° tangent manner.

4. The lower casing of a honeycomb sandwich structure battery pack according to claim 1, which can improve the collision safety of battery modules, is characterized in that, The biomimetic honeycomb sandwich structure contains an elastomer SBR sandwich layer between the two carbon fiber plates of the CFRP skin.

5. The honeycomb sandwich structure battery pack lower housing according to claim 1, characterized in that, The CFRP skin, SBR elastomer, and internal aluminum honeycomb core of the biomimetic honeycomb sandwich structure are all connected by adhesive bonding.

6. The lower housing of a honeycomb sandwich structure battery pack according to claim 1, which can improve the collision safety of battery modules, is characterized in that, The solid aluminum plate is made of aluminum alloy 6061, the skin of the biomimetic honeycomb sandwich structure is made of carbon fiber reinforced composite material, the honeycomb core is made of aluminum alloy 6061, and the elastomer sandwich is made of rubber material.

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