The Heat Transfer Coefficient is a physical quantity that measures the rate of heat transfer per unit area per unit time, indicating the ability of heat to transfer from one medium to another. Its unit is W/(m²·K), which means the number of watts transferred per square meter of area per degree Celsius increase or decrease.
In the battery system (especially in the Battery Thermal Management System BTMS), the thermal conductivity coefficient is used to evaluate:
The heat exchange efficiency between the battery and the cooling plate, the heat exchange rate between the liquid cooling/air cooling medium and the battery, and the thermal conductivity between material interfaces (such as thermal interface materials TIM).

