The structural design of a refrigerant plate and its flow property affect the thermal management performance of a battery. This study, aimed at improving the cooling and thermal uniformity based on the R134a cooling method, analyzed the flow resistance of the plate, temperature, and heat-transfer coefficient of the top board of eight types (type A-G) by the computational fluid dynamics method. By trade-off between flow resistance and heat-transfer efficiency, we determined the optimal type G plate with a modest pressure difference of 1670.6 Pa and the highest heat-transfer coefficient of 810.8 W/(m(2)K). In addition, the relationship between the operating parameters and temperature variation in battery modules and its uniformity has also been analyzed. The results indicate that with this novel cooling method, temperature uniformity of battery modules can be maintained within 5 K at 2C discharging rate. Both increasing inlet R134a flow rate and decreasing evaporative pressure obviously increase the temperature decrease rate of battery modules. With the inlet R134a mass flux ranging from 245 to 490 kg/(m(2)s), the evaporative pressure ranging from 412 530 to 291 220 Pa, and the subcooling degree ranging from 0 to 4 K, the battery temperature can be maintained under 300 K. In conclusion, this study develops the guidelines for battery thermal management based on refrigerant cooling, which has a promising application foreground due to its good thermal control performance, flow resistance saving, and lightweight.