Patent ID: 7693671

Claim:
A battery control device comprising: a voltage measuring unit to measure a voltage of a battery; a current measuring unit to measure an electric current of the battery; and a power source control unit to calculate an open-circuit voltage of the battery based on the voltage of the battery and the electric current of the battery, and to calculate a battery residual quantity ratio of the battery by use of relative information representing a relationship between the battery residual quantity ratio defined as a value representing a ratio of a residual quantity of the battery to a total capacity of the battery and the open-circuit voltage, and by use of the calculated open-circuit voltage, wherein the power source control unit calculates a charge quantity ratio of the battery by subtracting a battery residual quantity ratio of the battery at charge ending time from a battery residual quantity ratio of the battery at charge starting time, calculates a value obtained by multiplying the charge quantity ratio by a correction coefficient as a charging-discharging count of the battery, and integrates the charging-discharging count each time the charging-discharging count is calculated.