Author(s)

Jiacheng Ni, Shichuan Wang, Kai Wu

Merchant Marine College, Shanghai Maritime University, Shanghai, China.

In order to improve the working efficiency of the power battery pack and prolong the service life, there is a problem of inconsistency among the individual cells. Based on the centralized equalization structure of the multi-output winding transformer, a three-stage hybrid equalization control strategy is designed for equalization. The equalization scheme realizes that the high voltage single battery transfers the energy to the low voltage battery cell during the charging of the battery pack, improving not only charging efficiency and energy use loss, but also the high voltage battery transferring the power to the low voltage battery cell when the pressure difference is greater than 10 mv during the discharge. Between 5 mv and 10 mv, it performs passive equalization, reducing the output fluctuation of the power battery pack and achieving the balance purpose. During the standing time, the maximum active balancing operation within the battery pack is performed in order to achieve intra-group optimum consistency. It is proved by experiments that the equalization control method can realize the quick and effective equalization in the battery pack, and the energy balance of each single battery.

Inconsistencies, Active Equalization, Energy Balance, Power Battery Pack

Ni, J. , Wang, S. and Wu, K. (2019) New Composite Equalization Strategy for Lithium Battery Packs. Open Journal of Applied Sciences, 9, 172-180. doi: 10.4236/ojapps.2019.94015.