Thermal characteristics investigation of lithium-ion battery under high-frequency ac excitation in low-temperature environment
Zhongxiaobang Hu, Yang Li, Furong Liu, Bo Zhao, Weibo Li, Ruixin Yang, Changjun Xie, and Ying Shi
Published in IEEE Transactions on Transportation Electrification, September 20, 2021 [Link]
Citation: Zhongxiaobang Hu, Yang Li, Furong Liu, Bo Zhao, Weibo Li, Ruixin Yang, Changjun Xie, and Ying Shi, "Thermal characteristics investigation of lithium-ion battery under high-frequency ac excitation in low-temperature environment," IEEE Transactions on Transportation Electrification, vol. 8, no. 1, pp. 407-419, Mar. 2022, doi: 10.1109/TTE.2021.3113945. [Copy]
At low operating temperatures, the power capability and charging/discharging capacity of lithium-ion (Li-ion) batteries can decay rapidly. Therefore, it is essential to preheat the Li-ion batteries in advance of the normal operations of a battery electric vehicle. High-frequency ac preheating methods are advantageous to achieve a miniaturized and lightweight design. In this article, a self-heating circuit topology is used for studying the characteristics of Li-ion batteries at low temperatures and under high-frequency ac excitation. The thermal behaviors of Li-ion batteries under high-frequency ac excitations are comprehensively analyzed with an improved heat generation model. Experimental results exhibit that heat generation due to electrochemical reactions has a significant influence on self-heating rates under the high-frequency ac excitation, and the heating rate is positively correlated with the current frequency and root-mean-square (rms) value. Specifically, when the current frequency is 90 kHz and the rms value is 3.51 A or 1.17 C, validated by experiment and numerical simulation, a 2.9-Ah 18650 Li-ion cell can be heated up from −20 °C to 5 °C in 7.33 min with an average electrochemical heat generation of 2.962 W.