Aluminum alloy battery box body for new energy automobile and preparation method of aluminum alloy battery box body

[0036] Example 1

[0037] The invention provides an aluminum alloy battery box for new energy vehicles, such as figure 1 As shown, it includes three upper, middle and lower combined boxes and a box cover 4. The upper, middle and lower combined boxes (5, 6, 7) and the box cover 4 pass through the The mounting hole 9 is assembled with bolts, and the sealing groove 15 of the combined box body is provided with a sealing gasket to play a sealing role.

[0038] Among them, such as figure 2 with 4 As shown, the combined box body is a structure with an open end enclosed by a bottom plate 2 and a box wall 1. A number of bottom support beams 3 are fixed on the bottom plate 2, such as image 3 As shown, the box wall 1 includes a box wall body 11 and transverse ribs located at the top and bottom ends of the box wall body. The transverse ribs include an upper transverse rib 12 located outside the top end of the box wall body, a lower transverse rib 13 located at the outer side of the bottom end of the box wall body, and an inner lower For the transverse ribs 14, the box wall main body 11 is a flat structure with a cavity 16 inside, and the cavity 16 is provided with a reinforcing rib 17 therein. The arrangement of the upper and lower transverse ribs in this structure strengthens the rigidity of the box body and ensures that the box body is not easily bent when subjected to lateral force; the box wall body of the cavity section aluminum alloy profile structure not only reduces the weight of the box body, but also increases the box wall The large surface area improves the heat dissipation effect, and at the same time can absorb the side impact and protect the battery inside; in addition, the reinforcing rib 17 provided in the middle of the box wall body also ensures the strength of the box wall.

[0039] Preferably, in terms of technology, the entire box wall is integrally formed by an extrusion process, and the upper surface of the box wall (that is, the upper surface of the upper transverse rib) is provided with a sealing groove, and the box cover, the combination box or the combination box are installed on the combination box. When other components are embedded in the gasket, the sealing effect is achieved; the lower surface is provided with a stepped limit groove 18 that matches the structure of the bottom plate, such as image 3 with 4 As shown, the step is the position where the bottom plate is embedded. When welding, the bottom surface is up for welding. The solid area directly above the step is used to support the weld and prevent collapse during the welding process. This structure can be better used The bottom plate 2 is fixed by welding.

[0040] At the same time, a connecting hole 19 is opened on the lower transverse rib inside the bottom end of the main body of the box wall, which is used to fix various components inside the box, such as components such as the battery 8; on the upper and lower transverse ribs outside the top and bottom ends of the main body of the box wall A number of mounting holes 9 are opened, and the mounting holes 9 are matched with bolts for installing the box cover 4 (the mounting holes of the upper combined box in this embodiment are used for installing the box cover 4) or when stacking between combined boxes Used to connect and fix the entire battery box.

[0041] The preparation steps of the aluminum alloy battery box in this embodiment include:

[0042] 1. Extrusion: Six-series aluminum alloy aluminum alloy (6005 or 6082) is used to extrude the cavity and other cross-section box wall profiles through the extruder;

[0043] 2. Sawing: Cut the extruded cavity and other cross-section box wall profiles to length to the required length;

[0044] 3. Aging treatment: heat treatment of the sawn profile, the heat treatment condition is 160~170℃ for 8~10h aging treatment;

[0045] 4. Friction stir welding: weld the welded box wall and bottom support beam and bottom plate (the bottom plate is made of rolled five-series/six-series aluminum plate) to the box wall with friction stir welding plate, and weld the bottom surface upward when welding , The solid area directly above the step is used to support the welding seam and prevent collapse during the welding process. This structure can be better used to weld and fix the bottom plate 2;

[0046] 5. Argon arc welding: Use welding robots to weld the box walls 1 to 4 and the bottom support beam together;

[0047] 6. Numerical control processing: use CNC numerical control machine tool to process the installation surface of the box body, and perform drilling and tapping processing;

[0048] 7. Surface treatment: Surface treatment of the processed box to prevent surface oxidation and corrosion;

[0049] 8. Combined installation: The combined box obtained through steps 1-7 is fixed and combined with bolts to form the target battery box.

[0050] The performance parameters of the box wall prepared by this method are tested as follows:

[0051] classification Tensile strength (MPa) Yield strength (MPa) Elongation(%) Craft 6005 270 231 11.8 160°C, 10 hours 6082 323 304 9.2 170°C, 8 hours

[0052] From the above data, it can be concluded that the four box walls of the battery box of the present invention adopt a cavity + stiffener design, which not only reduces the weight of the box, but also realizes the lightweight of the car, but also ensures the strength of the box wall; The battery box can absorb kinetic energy through the deformation of the material (reinforcing ribs deform and absorb kinetic energy) when subjected to a side impact force, so as to protect the battery inside the box. Compared with the solid structure of the battery box of the present invention, Will transfer the kinetic energy of the impact directly to the inside of the box, which is likely to damage the battery, such as Figure 5 Shown in.