Battery Management System (BMS)

Overview

The battery management system (BMS) is a control system that protects the safe use of power batteries. It monitors the battery's usage status at all times, alleviates the inconsistency of the battery pack through necessary measures, and provides protection for the safe use of new energy vehicles.

BMS Basic Functions

• Current acquisition

• Single cell voltage collection

• Total voltage acquisition

• Temperature collection

• Insulation resistance test

• High voltage interlock detection

• Vehicle communication

• Accessory Control

• Battery status estimation

• High voltage power on and off control

• Thermal Management

• Balance control

• Charging Management

• Battery failure analysis and online alarm

• Functional Safety

BMS RoadMap

The BMS product layout is shown in the figure below, covering battery pack types from 12V to 800V, and taking into account the usage environment of passenger cars and commercial vehicles.

BMS Core Algorithm

• Closed-loop SOC estimation strategy based on Kalman filtering to improve SOC estimation accuracy

• Model-based online identification of capacity and internal resistance, monitoring of battery aging state (SOH)

• The remaining energy (SOE) estimation takes into account the changes in operating conditions to ensure the accuracy of vehicle range estimation

• Multi-state joint estimation strategy to ensure the accuracy of state estimation throughout the life cycle

• Early identification of internal short circuits prevents them from evolving into thermal runaway and ensures safe battery use

• Based on the balancing strategy of consistent power, the available capacity of the battery pack is fully utilized