A Power Management IC Used for Monitoring and Protection of Li-Ion Battery Packs

Abstract

A power management system is a critical component of the system which needs Li-ion battery packs for power supply. This paper proposes a fully integrated, high-precision, and high-reliability Integrated Circuit (IC) for the power management system of Li-ion battery packs. It has full protection circuits including overvoltage, overtemperature, and overcurrent circuits with measuring voltage accuracy of 0.2 mV and a 15-bit internal Successive Approximation Register (SAR) Analog-to-Digital Converter (ADC). This IC is designed to protect the system automatically and measure the battery cells' voltage, temperature, and charging or discharging current with high precision. It also provides an I2C interface to communicate with an external Microcontroller Unit (MCU), making it achievable to perform battery cells' voltage balancing and SOC estimation with 0.1% estimation accuracy in an hour.