ELECTRIC POWER SUPPLY SYSTEM

An electric power supply system includes a battery, an electric power receiving apparatus, a switching apparatus, and a control apparatus. The electric power receiving apparatus is coupled to the battery in parallel with a load, and receives and supplies external electric power to the battery. In a load driving mode, the control apparatus sets an electrical connection state of the electric power supply system to a first connection state in which connection of the electric power receiving apparatus and the load to the battery is cut off by the switching apparatus and controls a voltage of the electric power receiving apparatus depending on a voltage of the battery if output electric power of the electric power receiving apparatus is equal to or less than reference electric power, and otherwise sets the electrical connection state to a second connection state in which the connection is allowed by the switching apparatus.