Investigation of power battery heat generation measurement method with insulated cotton

Thermal management systems of power batteries have attracted a great deal of attention because of thermal safety and thermal runaway problems. The heat generation measurement is significant in researching and designing the thermal management systems. Therefore, effective method of measuring total heat generation experimentally is put forward, which insulated cotton is used as heat preservation layer for temperature rise measurement. The results show that insulated cotton can effectively reduce the heat dissipation. Compared with the absence of insulated cotton, the temperature rise (Delta t(cot)) of battery with insulated cotton is increased by 80.2%, 70.2% and 56.0% at 1 C, 2 C and 3 C, respectively. Furtherly, the heat dissipation during the discharge process has been evaluated by the temperature drop (Delta tau) under the shelving condition following the Newton's cooling formula. Towards to the amendment of the battery temperature rise (Delta t(cot)) measurement, the temperature rise of the high and low temperature chamber should be set to (Delta t(cot) + Delta tau) while the battery had discharged in it. In this way, more accurate measurement of the battery temperature rise (Delta t(total)) is obtained. Compared with the theoretical heat generation calculated by energy conservation law and energy conversion method, it reveals that battery temperature rise (Delta t(total)) can accurately calculate the heat generation of the battery.