Experimental Study on Thermal Management of Cylindrical Li-ion Battery with Flexible Microchannel Plates

A novel thermal management system of cylindrical Li-ion battery with the liquid cooling in flexible microchannel plate was established in the study. The experiments were conducted with R141b in flexible microchannel plates. The cooling system with the flexible aluminum microchannels can effectively transfer heat from battery to the cooling refrigerant R141b based on flow boiling. A battery module with five cells along flow channel was chosen to study the effects of contact surface area and mass flux on the thermal performance and electrochemical characteristics in the experiments. Three types of structure with different contact areas were studied and their performances were compared with the experiments without cooling structures. The experiments were carried out at the same discharge rate with the inlet mass flow rates of 0–10 kg/h. For the inlet mass flow rate of 5.98 kg/h, the surface temperature and temperature uniformity of battery were the best, and the output voltage and capacity of batteries were higher than those under other mass flow rates. With given inlet mass flow rates, the five series cells exhibited different electrochemical performances, including output voltage and discharge capacity, due to the different refrigerant flow states in the microchannels. Finally, an optimal design was presented with thermal performances, macroscopic electrochemical characteristics, inlet mass flow rates and cooling performance taken into consideration.