With the increasing severity of environmental issues and the continuous rise in people’s pursuit of living quality, batteries have become an indispensable key component in modern life. To eliminate potential safety hazards during battery pack usage and maximize energy utilization efficiency, battery balancing technology has become a crucial part of Battery Management Systems (BMS). This paper focuses on bidirectional active balancing architecture and functional management aspects of BMS, designing a two-level bidirectional active balancing battery management system based on DC/DC converters. This provides a new design solution for engineering practices in actual application scenarios.