Experimental Investigation of Lithium-Ion Battery Cell Heating Under Subzero Conditions Using Induction-Based Liquid and Internal DC Heating

Abstract

This study investigates the thermal and electrical performance of a hybrid heating strategy for lithium-ion batteries operating under extreme cold conditions. A novel heating configuration is proposed, integrating electromagnetic induction-based fluid heating with direct current (DC) excitation during a 3C discharge. Experiments were conducted on a cylindrical 18,650 NMC cell to evaluate the effects of three induction power levels (100, 250, 400 W) and three liquid flow rates (0.22, 0.30, 0.50 l/min) on critical performance parameters including heating rate, heating efficiency, and discharge behaviour. Results show that the hybrid method delivers significantly faster heating compared to using DC heating alone. The fastest temperature rise was recorded at 0.22 l/min and 400 W, reaching 0 degrees C, 15 degrees C, and 25 degrees C in 43.3 s, 69.3 s, and 177.9 s respectively, with a peak heating rate of 21.43 degrees C/min to 15 degrees C. However, at this low flow rate, nucleate boiling was observed, which may act as a limiting factor by introducing instability to the system. Increasing flow rates improved heat transfer by convection but slightly reduced heating rate due to shorter thermal contact time. Heating efficiency was highest at low power and flow rate and declined with increasing power. Voltage profiles demonstrated improved discharge performance in all hybrid cases, with the duration until voltage cut-off extending from 902 s (no induction) to 1037 s (0.22 l/min, 250 W). Compared to existing studies, the proposed system offers one of the fastest heating rates (11.80 degrees C/min) reported among external battery heating methods. These results highlight the strong potential of induction-liquid based DC heating systems for rapid and reliable battery preheating in electric vehicles under cold climate conditions. While the proposed system shows promising preheating performance, its practical integration into existing electric vehicle architectures requires further investigation regarding control complexity, safety compliance, and component miniaturization.