Experimental and numerical investigation of fast preheating of lithium ion pouch cell via low-power inductive heating in cold climate

Abstract

The fast preheating of lithium ion batteries (LIBs) is a challenge hindering its wide application in cold climate. This study proposes a new preheating method that employs an inductive heating operation. The performance of inductive heating on LIB is evaluated and compared with conventional heating methods using metal resistance film (MRF) and positive temperature coefficient (PTC) elements. Subsequently, an inductive heating numerical model is established to investigate the influence of critical factors, including current frequency and battery thickness, on the inductive heating performance. Results show that conventional MRF and PTC heating cannot provide safe fast preheating of LIBs owing to significant temperature difference inside battery. In comparison, inductive heating offers a better battery preheating performance with fast temperature increment, uniform temperature distribution and high efficiency. The battery utilizing sandwich inductive heating achieves a temperature increase rate up to 71.4 °C/min, an insignificant temperature deviation less than 6 °C, and a heating efficiency of 79.2% in the experimental test. The higher temperature uniformity of inductive heating is attributed to the fact that heat is generated within the battery electrode layers and that the contact thermal resistance induced by battery case can be eliminated. Moreover, the inductive heating performance is highly related with current frequency and battery thickness. The inductive heating of LIB is more suitable for operations at low frequencies, such as 10 kHz, as the skin effect of inductive heating can be decreased, and the temperature uniformity is increased. The battery thickness less than 4 mm is recommended as the maximum temperature deviation is less than 2 °C. This paper provides a preliminary investigation into the feasibility of LIB inductive preheating technology and offers new insights into the thermal management design of LIB application in cold climates.