The performance of the battery cooling unit is critical to the safe

efficient

and reliable operation of the power battery in a vehicle. Based on the process of refrigerant direct cooling

an 8-kW power battery cooling unit for use in a pure electric truck was designed and developed. The performance of this unit was tested in both a lab and the truck itself. The results showed that if the temperature of the cooling plate located at the bottom of the battery was between 5 and 10 ℃

the highest temperature in the battery core could be reduced to 35 ℃. In addition

the refrigeration capacity could reach 7.8 kW with dual compressor cooling system. The temperature difference between the inlets and outlets of 15 cooling plates was less than 5 ℃ when the distributor and capillary were combined. In a high-temperature environment

the vehicle battery cooling unit used in the truck could maintain an average battery-core temperature of less than 28 ℃. Different inlet temperatures of cooling plates could be controlled within a range of 7–10 ℃

whereas the outlet temperature could be controlled within 9–13 ℃

which is very effective for the cooling of battery. In addition

the influence of refrigerant charge and the opening degree of the H-type thermal expansion valve on the performance of the unit were analyzed

and the control strategy of the unit was formulated and evaluated.