POWER-RECEIVING DEVICE, CONTACTLESS POWER-FEEDING SYSTEM, AND COVER UNIT

A wireless power-supplying system (1) includes a power-supplying coil (15) disposed on a ground contact surface side, a power-receiving coil (21) mounted on a movable body and to which power is wirelessly supplied from the power-supplying coil (15), a cover member (31) provided in the movable body and configured to be opened and closed and cover the power-receiving coil in a closed state, and a bag (33, 33A) configured to expand and contract and to open and close the cover member.