Researchers at the Korea Advanced Institute of Science and Technology (KAIST) have developed a new technology that can diagnose and monitor the condition of EV batteries with high accuracy using only small amounts of current, aiming to increase stability and long-term efficiency.
The research team, led by Professors Kyeongha Kwon and Sang-Gug Lee from the School of Electrical Engineering, developed electrochemical impedance spectroscopy (EIS) technology that measures the magnitude of impedance and changes in the battery to assess battery efficiency and energy loss. It can assess the state of charge (SOC) and state of life (SOH) of batteries, identify thermal characteristics and chemical/physical changes, predict battery life, and determine causes of failure.
The EIS system can accurately measure battery contact with low current disturbances (10 mA), reducing thermal effects and safety issues during the measurement process. The system minimizes bulky and expensive components, making it easier to integrate into vehicles. Researchers have demonstrated its effectiveness in determining the electrochemical properties of batteries under various operating conditions, including different temperatures and SOC levels.
The study, in which Young-Nam Lee, a doctoral student in the School of Electrical Engineering at KAIST participated as first author, was published in IEEE Transactions on Industrial Electronics.
“This system can be easily integrated into the battery management system (BMS) in electric vehicles and demonstrate high measurement accuracy while significantly reducing cost and complexity compared to current conventional EIS methods. It can have an impact on battery diagnosis and performance improvement not only in electric vehicles but also in energy storage systems (ESS),” explained Professor Kyeongha Kwon.
Source: KAIST