New breakthrough in estimation of State of Charge (SOC) of lithium-ion battery has been achieved by Prof. CHEN Zonghai, from School of Information Science and Technology. His research project, "Key Technology and System of Energy Management for Renewable Energy Vehicles", receives the attention from International Energy and Environment Sector, which helps him become a nominee of the ENI award. Now, this award is still in review.

With the development of electric vehicles and the arrival era of energy storage, lithium-ion battery has become the strong driving force for emerging industries. However, the current packing lithium-ion battery has a short service life and it’s difficult to estimate the SOC, which might lead to low safety, insufficient reliability, inefficient energy conversion, poor state of health (SOH) and limited endurance mileage of electric vehicles. Focusing on these problems, Prof. CHEN has studied the estimation of SOC of lithium-ion battery both in theory and technological development. He successfully describes the complex behaviors of battery system under the actual working conditions using a new combined model of cell SOC and battery pack SOC. Moreover, several strategies of SOC estimation has been put forward which innovates the description method of state variable in SOC estimation and realize the synchronization estimation of SOC and drift current. His innovative lithium battery management system has been founded and put into demonstration applications. His accomplishment is a significant step forward providing new solutions to practical issues. The main theoretical results were published in issue 101&113 of "Applied Energy".

Cell and Pack SOC (state of charge) estimation in EVs(Electric Vehicles). The data of cells within a battery pack, such as voltage, current, temperature, et al., are collected by distributed BMUs (Battery Management Units) and then processed by CCU (Central Control Unit) with different battery models under different estimation strategies. The SOC of the pack, the SOC of each cell, and some other critical data are calculated and displayed in several panels both for engineers and customers. /Photo from CHEN's group.

As one of the few Chinese nominee of the ENI award, known as the unofficial “Nobel Prize of energy research” aiming at encouraging better use of energy sources and increased environmental research, CHEN Zonghai makes a new history in this field. He was conferred his bachelor’s degree in USTC in 1988 and Master’s degree in 1991. Now, Prof. CHEN concentrates on the research of control science and engineering. His excellent work has been recognized by academic circle and economic circle. Due to a series of research achievements, Prof. CHEN has attained numbers of awards, including MOE technological award. At present, he is a member of technical committee of International Federation of Automatic Control (IFAC), a director of Chinese Association of Automation and an executive director of Chinese Association for System Simulation.

(CHEN Yaoyao, USTC News Center)