A charging method, applied in a charging system comprising a charging adapter and a mobile terminal, and comprising: with a cell detection circuit, acquiring a voltage value of a cell, and sending the voltage value of the cell to a second controller, wherein the charging adapter comprises the second controller, and the mobile terminal comprises the cell detection circuit and the cell; with the second controller, searching a threshold range table to obtain a current adjusting instruction matched with a threshold range containing the voltage value of the cell, and sending the current adjusting instruction to an adjusting circuit, wherein the charging adapter comprises the adjusting circuit, the threshold range table records one or more threshold ranges and one or more current adjusting instructions having a one-to-one mapping relation with the one or more threshold ranges; and with the adjusting circuit, performing a current adjustment according to the current adjusting instruction, and outputting a power signal after the current adjustment, wherein the adjusting circuit comprises a current detection circuit; with the adjusting circuit performing a current adjustment according to the current adjusting instruction and outputting a power signal after the current adjustment specifically comprises: with the current detection circuit, detecting a current value of the power signal outputted by the adjusting circuit, and sending the current value detected to the second controller; characterized is that with the second controller, calculating a difference between the current value detected and a current value specified by the current adjusting instruction, and sending a calibration instruction to the adjusting circuit if an absolute value of the difference calculated is greater than a difference threshold; and with the adjusting circuit, calibrating the power signal according to a current difference specified by the calibration instruction, and outputting a calibrated power signal, wherein a current value of the calibrated power signal is equal to the current value specified by the current adjusting instruction. with a cell detection circuit, acquiring a voltage value of a cell, and sending the voltage value of the cell to a second controller, wherein the charging adapter comprises the second controller, and the mobile terminal comprises the cell detection circuit and the cell; with the second controller, searching a threshold range table to obtain a current adjusting instruction matched with a threshold range containing the voltage value of the cell, and sending the current adjusting instruction to an adjusting circuit, wherein the charging adapter comprises the adjusting circuit, the threshold range table records one or more threshold ranges and one or more current adjusting instructions having a one-to-one mapping relation with the one or more threshold ranges; and with the adjusting circuit, performing a current adjustment according to the current adjusting instruction, and outputting a power signal after the current adjustment, wherein the adjusting circuit comprises a current detection circuit; with the adjusting circuit performing a current adjustment according to the current adjusting instruction and outputting a power signal after the current adjustment specifically comprises: with the current detection circuit, detecting a current value of the power signal outputted by the adjusting circuit, and sending the current value detected to the second controller; characterized is that with the second controller, calculating a difference between the current value detected and a current value specified by the current adjusting instruction, and sending a calibration instruction to the adjusting circuit if an absolute value of the difference calculated is greater than a difference threshold; and with the adjusting circuit, calibrating the power signal according to a current difference specified by the calibration instruction, and outputting a calibrated power signal, wherein a current value of the calibrated power signal is equal to the current value specified by the current adjusting instruction.