Constant current (CC) charging is a dominant charging process before the battery can be fully charged and the battery is considered as an equivalent resistance with a wide range variation during the process. However, a wide load range variation causes the transfer efficiency of inductive power transfer (IPT) converter to deviate from the optimum point. Therefore, transfer efficiency optimization measures are required during battery CC charging process with IPT converter. Herein, this paper proposed a suitable bivariate control method for a single-stage IPT converter based on inductor-capacitor-capacitor-series (LCC-S) compensation topology, which keeps the converter output current constant and improves transfer efficiency. The newly adopted bivariate control method includes two control variables, the conduction angle of the voltage-controlled semi-active rectifier (VCSAR) and the operating frequency of the inverter. The equivalent load of the VCSAR is adjusted by controlling the conduction angle, and at the same time, the operating frequency of the inverter is controlled to ensure constant current output. Finally, simulation results are presented to verify the effectiveness of the bivariate control method for the LCC-S compensated IPT converter. In addition, zero-voltage switching (ZVS) can be realized in both sides of the converter.