Reverse-Pulse Charging Method of Lithium Batteries for Stable Charging at Low Temperatures

Traditional lithium-ion battery (LIB) charging methods that are stable and fast at room temperature do not guarantee high performance at low temperatures because the impedance of LIBs changes at low temperatures. Most existing methods for stable charging at low temperatures require additional LIB terminals to sense lithium plating or require a long charging time because the average current is gradually lowered. This paper proposes a reverse-pulse current charging method to charge LIBs faster than existing charging methods at low temperatures in a safer manner. The proposed method overcomes the limitations of existing low-temperature charging methods, such as the need for additional terminals and long charging times, primarily because the proposed method does not require sensing of lithium plating and is set to have the same values of average current values as the constant current (CC). Simulations and experiments verify the effectiveness of the proposed charging method at low temperatures. The proposed method improves the capacity fade rate of traditional CC charging by 61% while maintaining the charging speed, enabling stable and fast charging for LIBs.