Isolated Multi-Cell Single-Path Battery Management System for Electric Vehicle Batteries

Wan Hae Jeon; Innyeal Oh

doi:10.23075/jicas.2025.11.3.008

Wan Hae Jeon Sunmoon University
Innyeal Oh Sunmoon University

DOI: https://doi.org/10.23075/jicas.2025.11.3.008

Keywords: Battery management system (BMS), cell monitoring, balancing, isolated structure, photo, resolution

Abstract

A Battery Management System (BMS) is essential for monitoring battery voltage and maintaining balance in high-voltage environments. This study applies an indirect measurement approach using an isolated structure, where LEDs are used for voltage sensing and balancing. In order to monitor the accurate voltage even in the PVT environment, the multiple battery voltages were monitored with a multi-cell single path structure, and an internal reference voltage was generated to ensure the monitoring result compensated for temperature, even with battery temperature changes. BMS executes to get cell monitoring and reference voltages in one output port while performing temperature compensation, andindependently, the cell-by-cell register operation method allows simultaneous balancing of multiple cells. As a result of the design, the voltage resolution within +/-5mV from -20 degrees to +80 degrees was secured, and the balancing operation was secured at more than 20mA. This allows the battery voltage monitoring and cell balancing to be stable with the proposed isolated circuit structure in high-voltage environments.

Author Biographies

Wan Hae Jeon, Sunmoon University

Wan-Hae Jeon received his bachelor’s degree in embedded engineering from the Department of Future Automotive Engineering at Sunmoon University in 2024. He is currently pursuing his master’s degree in mobility semiconductor engineering at Sunmoon University in Asan, Chungcheongnam-do. His current research interests include BMS semiconductor design and communication semiconductor design

Innyeal Oh, Sunmoon University

Inn-Yeal Oh’s academic journey began at Kwangwoon University, Seoul, where he earned his BS in 1993, MS in 1996, and PhD in 2003, all in electrical engineering. From 1996 to 1999, he worked with LG Electronics, where he contributed to the development of Mobile communication and Digital TV systems.

From 2003 to 2005, he worked with Hampex Inc..(Samsung handset design house) as a team leader, developing a CDMA/GSM handset. From 2007 to 2015, he worked with the Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Korea, where he was a research associate professor with the Department of Electrical Engineering. Since 2021, he has been with Sun Moon University, Asan Chungnam, Korea, where he is an associate professor with the Department of Advanced Automotive Engineering. His research interests include the design of automotive sensors, V2X semiconductors, AI maintenance, and convergence solutions of next-generation automotive technology.