Achieving a balance between lightweight and high strength in an aluminum extruded battery tray requires coordinated optimization across three core dimensions: material selection, structural design, and manufacturing processes. Aluminum alloy is the preferred material due to its low density, high specific strength, and corrosion resistance. With a density only one-third that of steel, it can significantly reduce weight under the same load conditions. By adding alloying elements such as magnesium and silicon, aluminum alloy's strength can be further enhanced while maintaining good ductility and toughness, laying the foundation for a balanced balance between lightweight and strength.
Structural design is key to balancing lightweighting and strength. The aluminum extrusion process allows for hollow or multi-chamber cross-section designs, reducing material usage while increasing structural rigidity. For example, a double-cavity frame and base plate structure reduces weight through thinning while leveraging the cavity's geometric inertia to enhance bending resistance. A combination of localized thickening and CNC machining further optimizes material distribution: Localized thickening enhances load-bearing capacity in high-stress areas such as battery module mounting points, while milling removes excess material from non-load-bearing areas, achieving a "demand-based" lightweight design. Furthermore, topology optimization technology uses finite element analysis to identify stress distribution patterns, removing material from low-stress areas while retaining critical force transmission paths. This allows the structure to achieve a "skeleton-like" weight reduction while meeting strength requirements.
Breakthroughs in manufacturing processes provide technical support for the coordinated optimization of lightweighting and strength. Friction stir welding, due to its unique solid-state welding properties, has become the preferred solution for joining aluminum extruded battery trays. Compared to traditional fusion welding, friction stir welding mechanically stirs the material into a plastic state and forms a dense weld, avoiding defects such as porosity and cracks that can easily occur during fusion welding. The weld strength can reach a high percentage of the parent material while also controlling welding distortion. For the complex connection between the frame and base plate, a combined process of external friction stir welding and internal MIG welding ensures joint strength while also addressing sealing issues that arc welding can cause through adhesive coating. Furthermore, precision control of the aluminum extrusion process itself is crucial. Gradient heating technology achieves isothermal extrusion, ensuring uniform core-surface temperature across the profile, reducing residual stress and improving the consistency and structural reliability of the finished product.
Integrated design further promotes the coordinated optimization of lightweighting and strength. Integrating functional components such as the liquid cooling plate and BMS bracket directly into the aluminum extruded battery tray structure reduces the number of independent components and connection interfaces, reducing weight while increasing overall rigidity through structural interlocking. For example, the baseplate cavity can be designed as a liquid cooling channel, sealed through friction stir welding. The coolant flow also enhances structural damping and vibration resistance. This integrated "function-structure" design approach transforms the aluminum extruded battery tray from a simple load-bearing component into a multifunctional integrated platform, achieving enhanced performance within a limited space.
The aluminum extruded battery tray's balance of lightweight and high strength is fundamentally a deep integration of materials science, structural mechanics, and advanced manufacturing technologies. Through the precise application of high-strength aluminum alloys, innovative biomimetic structural design, breakthroughs in solid-state welding processes, and the expansion of integrated design thinking, the aluminum extruded battery tray achieves significant improvements in bending stiffness and fatigue life while reducing weight, providing critical support for the extended range and safety of new energy vehicles.
