Abstract: In order to solve the low charging efficiency and low power of mine EPS,this paper develops a high-power EPS,its anode materials of battery pack is lithium iron phosphate.The whole system adopts PLC to control the group charging;and it realizes the balanced recharging.This design has applied in Kailuan coal mine.Experiments date show that the charging method has high charging efficiency as well as good safety.Meanwhile,EPS power can guarantee the normal operation of 30 kW critical load when the power system is in failure,which can meet the requirements of mining standby power.