Internal Heating Techniques for Lithium-Ion Batteries at Cold Climates: An Overview for Automotive Applications

Lithium-ion (Li-ion) batteries suffer from substantial capacity and power degradation at low temperatures, severely deteriorating the performance of battery-based transportation electrification. To overcome this issue, different preheating techniques have been proposed to recover the performance of Li-ion batteries in cold climates. Among these, internal heating schemes are more promising than traditional conductive and convective approaches owing to their superiorities in terms of high efficiency, rapid speed, and uniform temperature distribution. This article reviews various internal heating methodologies developed in recent years for Li-ion batteries, including mutual pulse current heating, alternating current (ac) heating, compound heating, and all-climate-battery (ACB)-based heating. Specifically, the effects of low temperatures on Li-ion batteries are first outlined in terms of cell performance and electrochemical characteristics. Then, the heat generation mechanism during internal heating is briefly described, based on which the internal temperature monitoring methods are also investigated considering the temperature gradient. Next, a comprehensive literature survey on different internal heating schemes with their basic principles, benefits, and drawbacks is presented. Finally, future trends of internal heating methods to benefit automotive battery performance are discussed in terms of key technologies, promising opportunities, and challenges.