Energy Storage BMS: Three-Level Architecture for Safety

This document introduces the energy storage battery management system (BMS) from Ligao (Shandong) New Energy Technology Co., Ltd. The BMS adopts a three-level architecture comprising the Battery Array Management Unit (BAU), Battery Cluster Management Unit (BPU), and Battery Module Management Unit (BMU). The BAU manages the overall battery stack, including state of charge (SOC) and state of health (SOH) calculations, fault diagnosis, and data interaction with PCS/EMS. The BPU oversees a cluster of battery packs, handling insulation detection, relay control, and balancing strategy analysis. The BMU collects real-time voltage and temperature data from battery modules and performs bidirectional equalization. Key product features include high insulation withstand voltage meeting GBT34131, high-resolution thermal management with multiple temperature control strategies, UL94-V0 flame retardant rating for critical components, distributed centralized management for simplified control, intelligent balancing for battery consistency, and operation authority encryption. The system supports 9-36V power input, multiple CAN and 485 communication interfaces, Ethernet, and SD card data storage. The BPU uses an SPC5742P MCU with ASIL-D functional safety level, supports daisy chain communication, and includes high-voltage detection and insulation detection with Y capacitance adaptation. The BMU offers cell voltage collection accuracy of ±5mV and temperature detection from -40°C to 125°C.