An equalization charging device of series connected lithium batteries is disclosed, relating to a battery charging device. The invention provides an introducing public energy pool structure. The invention provides the equalization charging device of the series connected lithium batteries, and the equalization charging device can solve a series connected lithium battery pack equalization problem well. The equalization charging device is provided with a multi-coil transformer, an energy conversion circuit, a voltage detection circuit, and a control unit. The energy conversion circuit is connected with a coil assembly of the multi-coil transformer and two ends of each single battery of a series battery pack respectively. A control signal input terminal of the energy conversion circuit is connected with a control signal output terminal of the control unit. A detection voltage input terminal of the voltage detection circuit is in parallel connection with the two ends of the single battery of the series battery pack. A detection voltage output terminal of the voltage detection circuit is connected with a detection voltage input terminal of the control unit.