Previously, soft switching methods for unidirectional inductive power transfer (IPT) systems were proposed. However, these methods were not applicable to bidirectional IPT system as it is. In addition, the appropriate capacitances of snubber capacitors for soft switching were not discussed in these papers. In order to achieve soft switching which can reduce switching loss, it is necessary to design the capacitances appropriately. Furthermore, it is necessary to consider the battery charging and discharging cycle in order to obtain higher efficiency in the charging pattern which is often used. Therefore, this paper shows the design guideline of the snubber capacitors for IPT systems by using the visual evaluation maps considering battery charging and discharging cycles. By using the design method, it becomes easy to decide the appropriate capacitances of the snubber capacitors. In addition, the effectiveness of the capacitances design guideline is clarified by the experiments. As the results, the soft switching could be achieved and the efficiency of the whole system with snubber capacitors could be improved by 0.9 % compared to the efficiency of the system without the snubber capacitors in the experimental condition.