  Nowadays, automobile is facing the trend of electrification. Lithium-ion
batteries is widely used as their power supplies. Lithium-ion battery has
complex characteristics, as a result, Lithium-ion battery needs optimal
charging strategies to make sure it is charged safely and efficiently. This
paper focuses on development of a high-efficient charging method for
lithium-ion battery. To test different charging strategies, the electric
vehicle charging system consisting of a dual active bridge DC-DC converter and
a Thevenin battery model is implemented. Multistage constant current charging
(MSCC) and multistage constant current reflex charging (MSCC with reflex
charging) were proposed. Compared with the traditional constant voltage
constant current (CC-CV) charging method, MSCC can reduce 12% of the charging
time and 1.1% of the battery loss; MSCC with reflex charging has a 10.45% and a
1.54% reduction of charging time and battery loss separately.
