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

摘要

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 power management system of Li-Ion battery packs. It has full protection circuits including over-voltage, over-temperature and over-current with measuring voltage accuracy of 0.5 mV, and a 14-bit internal successive approximation register analog- to-digital converter (SAR ADC) with 0.6 mV accuracy. 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 Micro Controller Unit (MCU), making it achievable to perform battery cells' voltage balancing and SOC estimation with 0.1% estimation accuracy in an hour.