Patent ID: 8831786

Claim:
A system for controlling charge or discharge of a battery of an electric vehicle, the system comprising: a receiver configured to: receive information related to a price of electricity according to time from a central server; receive an operation mode from a portable terminal or an in home display (IHD), the operation mode including a first mode in which the electric vehicle is operated after the battery is charged and a second mode in which the electric vehicle is not operated after the battery is charged; and receive a first price under which the battery of the electric vehicle is charged and a second price over which the battery of the electric vehicle is discharged, the first and second price being received from the portable terminal or the IHD; a transmitter configured to transmit information to at least the central server, the portable terminal, or the IHD; a charger configured to charge the battery; a discharger configured to discharge the battery; and a controller configured to: control the charger to charge the battery when the electric vehicle is in the first mode and the price of electricity is under the first price; control the charger to charge the battery when the electric vehicle is in the second mode and the price of electricity is under the first price; control the discharger to discharge the battery when the electric vehicle is in the second mode and the price of electricity is over the second price; calculate cost of electricity for charging or discharging the battery; estimate a total cost of electricity to be received from an electric power company for discharging the battery based on the information related to a price of electricity according to time; and monitor whether the calculated cost for charging or discharging the battery for a specific period of time exceeds a threshold cost; control the transmitter to transmit information related to the calculated cost of electricity or the estimated total cost of electricity to at least the central server, the portable terminal, or the IHD; and control the transmitter to transmit a warning message to at least the portable terminal or the IHD when the controller determines that the calculated cost for charging or discharging the battery for the specific period of time exceeds the threshold cost.