In order to achieve the research of high-efficiency laser wireless energy transmission system, a closed-loop control simulation model of laser wireless energy transmission system was established based on Simulink. In this model, the maximum power point tracking of laser photovoltaic array, the construction of voltage reduction circuit, and the intelligent charging control of lithium battery were realized. Combining the output characteristics of the laser photovoltaic array and the characteristics of the lithium battery multi-stage constant current charging method, a new type of lithium battery multi-stage constant current charging method based on the laser power density closed-loop signal control was proposed. The simulation results show that this method can not only realize the multi-stage constant current charging effect of traditional lithium batteries, but also save about 62.9% of the light energy and increase the conversion efficiency of the system by 62.96%. The study is helpful for the research of high efficiency laser wireless energy transmission system.