Patent ID: 8538616

Claim:
A power supply system for an electrically powered vehicle incorporating a motor for generating power to drive the vehicle and an internal combustion engine configured to be able to generate said power to drive the vehicle independently of said motor, said electrically powered vehicle having, as a travel mode, a first mode allowing said motor to generate said power to drive the vehicle and a second mode allowing said motor and said internal combustion engine to generate said power to drive the vehicle, said power supply system comprising: a main power storage device for supplying electric power to an inverter for driving and controlling said motor; a plurality of sub power storage devices provided in parallel to each other; and a switching control device configured to a selected sub power storage device for supplying electric power to said inverter, between said plurality of sub power storage devices, said switching control device including: a switching determination unit for determining whether said selected sub power storage device should be switched based on a state of charge of each of said plurality of sub power storage devices; and a connection switching unit configured to switch said selected sub power storage device when said switching determination unit determines that said selected sub power storage device should be switched, and said switching determination unit determining that said selected sub power storage device should not be switched regardless of said state of charge of said selected sub power storage device, while said travel mode is said second mode.