液态金属实现的热-电耦合电流传输性能分析

Abstract High-power direct current fast charging (DC-HPC) is expected to drive electric vehicles (EVs) towards high-energy efficiency and low-carbon sustainability while suffering potential thermal runaway due to extreme-high heat shock. Conventional cooling methods that separate current transmission and heat dissipation struggle to achieve efficient thermal management and structural flexibility, particularly under ultra-high charging current. Herein, a liquid metal (LM)-enabled coupled thermal-electric current transmission strategy is introduced to establish the flexible synergetic power line (FSPL) for EV supercharging even for currents exceeding 1000 A. With the synergetic functions of current-carrying conduction and active-cooling dissipation, the LM-enabled FSPL (LM-FSPL) can rapidly eliminate the superhigh heat density generated by ultra-high charging current, promoting structural simplification and reliable operation of DC-HPC. Experiment results demonstrate that LM-FSPL presents remarkable mechanical elasticity and flexible maneuverability while maintaining electrical stability, achieving a tensile and torsion deformation of 50 % and 720°. The multiphysics numerical method is also employed to thoroughly investigate the current-heat-fluid mechanisms of different transmission strategies. Compared with copper-based power lines, the LM-FSPL exhibits superior heat transfer and hydrodynamic performance by homogenizing current distribution, suppressing localized heat accumulation, and optimizing thermal-flow pathways, resulting in a 62.7 % improvement in active-cooling capability. Additionally, we built the LM-FSPL test platform to investigate the adaptability of the system under various geometric configurations and charging currents. Experimental results revealed that the maximum temperature achieved by LM-FSPL only is 37.6 ℃ at the charging current of 1000 A. Our coupled thermal-electric current transmission strategy offers new opportunities for ultra-high power charging to promote the popularization of EVs.