Balancing charge/discharge management for series/parallel battery packs

Abstract

We propose a battery management system with capacity equalization. The system can be used in arbitrarily series-parallel connected battery packs, and effectively manage batteries working in the charge or discharge mode. For the discharge mode, we develop a new method of battery capacity equalization, and determine the minimum number of battery for equalization. This system not only reaches balancing discharge but also meets the requirement of output power. For the charge mode, this system can individually adjust the charge current according to the battery energy storage status for a charge equalization. Furthermore, the battery can be immediately isolated while it is not working in the safe operating range.