Battery pack shell for new energy vehicle and manufacturing method of battery pack shell

Abstract

The invention discloses a battery pack shell for a new energy vehicle and a manufacturing method of the battery pack shell for the technical field of battery packs. The battery pack shell comprises abottom plate, a side frame and an upper cover, wherein a stamped and formed metal plate is adopted by the bottom plate; an extruded metal section is adopted by the side frame; the metal section is bent and then the end part is docked to form the side frame with a closed loop structure; a bottom plate connection end is formed at the bottom of the side frame; an upper cover connection end is formedat the top of the side frame; the bottom plate connection end of the side frame is connected with the bottom plate in a welding manner and a battery pack accommodating cavity is formed in the side frame; and the upper cover is matched with the upper cover connection end to cover the battery pack accommodating cavity. A whole plate stamping form is adopted by the bottom plate of the battery pack shell, so that the connection reliability of the bottom plate and a vehicle body floor is ensured while the stiffness is improved; and the section is short in mold making period and low in price and thestructure is large in design space, so that the side frame is formed by bending the section and carrying out tailor-welding, the side frame is connected with the bottom plate in a welding manner andthe welding strength and the strength reliability of the battery pack can be effectively ensured.

Description

technical field [0001] The invention is used in the technical field of battery packs, and in particular relates to a new energy vehicle battery pack shell and a manufacturing method thereof. Background technique [0002] New energy vehicles are developing rapidly under the promotion of national policies. As an important part of electric passenger vehicles, battery packs are generally installed under the body floor, and the battery pack shell bears the weight of the internal battery module and BMS control system. Currently, The cruising range of domestic pure electric vehicles is about 200-300 kilometers, and the weight of the battery pack is about 300 kg. With the continuous increase of cruising range, the weight of the battery pack is also increasing. Durability and other performance are crucial to the safety of the vehicle. On the other hand, the weight of the battery pack shell will also affect the energy density of the battery pack and the cruising range of the vehicle. ...

AI Technical Summary

Problems solved by technology

[0003] For the existing technology of the new energy vehicle battery pack housing, it is more common to weld steel sheet metal parts, such as the invention patent disclosed in CN105501041 A, but the weight of the housing in this manufacturing method is relatively heavy, and it is resistant to Corrosion performance is not good; some use aluminum alloy gravity casting, but this method has many casting defects, poor mechanical properties, and thicker wall thickness is not conducive to the lightweight of the battery pack shell; some use advanced casting technology such as aluminum alloy vacuum High-pressure casting, CN106694841A disclosed invention patent, the battery pack casing adopts this technology to reduce casting defects to a certain extent, reduce the shell wall thickness to 3mm, yield strength ≥ 140Mpa, tensile strength ≥ 230Mpa, elongation ≥ 7 %, but due to the limitations of the casting molding method, the wall thickness cannot be freely designed, and the mechanical properties of the casting structure will not be too high, so the defect of the casting method is that the mechanical properties are not high. Although the designed battery pack shell is relatively steel The sheet metal welded part is light, but the weight is still heavy, and the cost of the one-time investment in the mold is relatively large, and it is easy to repair the mold or even scrap the mold due to the unreasonable structural design of the battery case; there are also aluminum alloy friction stir welding, but this This type is generally suitable for butt joints, the acceptance limits of lap joints and corners are large, and the structural design is limited

Images