Mechanical System Innovation for Next-Generation Electric Vehicles: Lightweight and Energy Recovery Co-Design

Aiming at the technical bottlenecks of electric vehicles (EVs) in terms of range, energy efficiency and thermal management, this paper proposes an innovative mechanical system design scheme that integrates lightweight materials, topology-optimised structure and mechatronic energy recovery. Through multi-physics simulation and experimental verification, the coupling mechanism between mechanical design and electrochemical performance is revealed, providing theoretical support for the development of energy-efficient electric vehicles. The research adopts a hybrid structure of carbon fiber reinforced polymer (CFRP) and aluminum alloy, and combines it with topology optimization technology to achieve lightweight (18% weight reduction) and improved impact resistance (40% improvement in energy absorption) of the battery box; the design of a bimodal energy recovery system integrating flywheel energy storage and magnetorheological damper, which can achieve an energy recovery efficiency of 82.7% in urban conditions (12.4% higher than that of a single-motor solution); the design of an innovative mechanical system based on fractal theory to mimic an electric vehicle, which can support the development of high energy-efficiency electric vehicles.); the bionic thermal management flow channel based on fractal theory reduces the maximum temperature difference of the battery pack from 8.2°C to 3.1°C, and the pump power loss is reduced by 19%. The results provide a paradigm of engineering practice and theoretical innovation for the optimisation of mechanical systems in next-generation electric vehicles.