TITLE:
New Composite Equalization Strategy for Lithium Battery Packs
AUTHORS:
Jiacheng Ni, Shichuan Wang, Kai Wu
KEYWORDS:
Inconsistencies, Active Equalization, Energy Balance, Power Battery Pack
JOURNAL NAME:
Open Journal of Applied Sciences,
Vol.9 No.4,
April
17,
2019
ABSTRACT: 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.