Research On Novel Series Battery Equalization Charging System

The battery is the key problem in the development of Electric Vehicle. Batteries are in serials when implemented in EVs, so the cycle life and performance of the battery pack is different from a single one. Among all these factors that affect the performance of the battery pack, the most important is the unbalance in charge and/or discharge process besides the difference of battery manufacture technology. So far there are several methods for the battery pack's equalization, however, because of the effect, cost and practicability, these methods are not widely used.This paper aimed at the balancing Lead-Acid battery pack. After analyzed methods for balancing battery pack domestic and abroad, we proposed a novel balancing method for battery pack: separated charging balancing for battery individuals. The main research contains:1. Analyzed the factors that shorten the cycle life of battery pack as well as their causes. Then we studied different balancing methods both domestic and abroad. We also proposed a novel separated charging method.2. Designed the module for balancing the battery pack. We chose half-bridge converter, MC9S12D32 and SG3525 to design this module, and made printed circuit board.3. Simulated the module with MATLAB. After it was proved correct in theory, we made the module and debugged it. The result shows that the module satisfied the demands of design.