A Comparative Review of Conventional and Emerging Techniques for Battery State Assessment

Accurate assessment of the state of charge (SoC) and state of health (SoH) of batteries provides critical information for effective operation in various battery applications. Such information optimizes charging, discharging, fault isolation, and maintenance decisions. Conventional techniques have shortcomings, including accuracy, cost, speed, and invasiveness. Recent research has introduced novel techniques, many exploiting magnetic field changes that occur during battery operation. This literature review summarizes conventional and novel measurement methodologies, highlighting any limitations of each. While magnetic field and X-ray approaches can overcome many of the shortcomings of conventional methods, further research is necessary to reduce costs, enhance safety, and enable real-time monitoring. The development of accurate, quick, and cost-effective measurement techniques will accelerate the integration of batteries into a rapidly increasing range of applications, including battery energy storage systems for behind the meter in buildings, facilitating electrification goals and the expansion of renewable energy.