Method and system for detecting fusion of relay

A battery control system, comprising:

• a high voltage battery configured to transmit power to a driving motor;
• a motor controller including an inverter configured to drive the driving power;
• and
• a power relay assembly configured to execute switching to selectively supply battery power to a vehicle,
• wherein a controller is configured to determine whether at least one or more of a first relay and a second relay of the power relay assembly have been fused when a vehicle engine was turned on and adjust an OFF order of the first and second relays when the vehicle engine is turned off based on the determination of whether the first and the second relays have been fused when the vehicle engine was turned on.