Contents I. Introduction
Lithium-ion (Li-ion) battery featuring high energy density, long lifetime, and low self-discharge rate [1] has been widely applied in many important areas for more efficient and clean energies utilization, such as electric vehicle drive, microgrid, and renewable energy generation [2], [3], [4]. In a real system, temperature plays a significant role in the performance of a Li-ion battery, including safety, lifetime, and capability. High temperature may lead to a thermal runaway which must be effectively protected in time. Moreover, side reactions may occur at the electrode/electrolyte interfaces under high temperature, e.g., metal dissolution from the cathode [5], which will accelerate the battery's aging. On the other hand, low temperature will reduce the energy and power capability of the battery [6]. Thus, it is essential to maintain the battery's internal temperature within a well-defined range. Here, the “internal temperature” refers to the operating temperature inside a battery, which can be estimated from the battery's impedance [7], [8], [9].
