Synergized Heating and Fast Charging for Lithium-Ion Batteries at Low Temperatures

Low activity of Lithium-ion batteries (LIBs) at low temperatures is an essential barrier for the future popularity of electric vehicles. Low-temperature charging of LIB consumes much longer time than that at normal temperature, and even induces irreversible damage to the LIB. Motivated by this, an electrical-thermal model-based synergized charging method is proposed in this paper. In particular, a coupled electrical-thermal model is built and validated for accurately reproducing the battery dynamics within a wide temperature range. On this premise, the dynamic programming (DP) algorithm is employed to synergize the heating and charging of LIB optimally regarding the fast charging at low temperatures. Results suggest that the charging and heating processes can promote each other to achieve a fast refueling of the battery.