Prototype design and experimental study of a metal alloy-based thermal energy storage system for heat supply in electric vehicles

In cold climates, a large portion of the battery power in an electric vehicle is used to provide heat to the cabin, which can result in a significant reduction in mileage. In order to address this issue, a compact thermal energy storage system based on aluminum silicon alloy was proposed, and expected to be used in electric vehicles as the heat supplier, in which the output temperature and heat power are fully adjustable according to the heat demand. The charge/discharge characteristics and thermal insulation performance of the system have been studied. The energy density of the heat storage tank is 225 Wh/kg or 179 Wh/L. It can supply heat for more than 3 h under the discharge power of 1.5 kW, and the heat utilization rate is higher than 80%. Compared with using the battery power for cabin heating, this device is economically favorable due to the high energy storage density and low cost. Therefore, the proposed TES heating system in this work provides a promising solution to save battery power for extending the cruising range at low temperatures.