Patent ID: 8299759
Filing Date: 2012-10-30
Classification: G01R,H02J

Abstract:
1. A battery pack, comprising: at least one secondary battery; a first terminal and a second terminal that are connected to an external electronic apparatus and perform charge and discharge; a discharge control switch that is controlled by a first control signal and turns on/off a discharge current with respect to the secondary battery; a charge control switch that is controlled by a second control signal and turns on/off a charging current with respect to the secondary battery; and a control section to detect a voltage, a current, and a temperature of the secondary battery, control the charge control switch and the discharge control switch by outputting the first control signal and the second control signal in accordance with the voltage, the current, and the temperature of the secondary battery, and calculate a battery capacity of the secondary battery, wherein the control section calculates the battery capacity of the secondary battery by different methods in accordance with respective cases where the secondary battery is being charged, being discharged, and in a fully charged state, and wherein in the case where the secondary battery is being charged, the control section calculates the battery capacity necessary to reach a full charge of the secondary battery by using a change amount of the charging current with respect to the battery capacity, and calculates the battery capacity of the secondary battery by using an adjustment value obtained based on the calculated battery capacity necessary to reach the full charge of the secondary battery, and in a case where the secondary battery is being charged with a constant voltage, the control section calculates the adjustment value from a ratio of the battery capacity necessary to reach the full charge of the secondary battery, the battery capacity being calculated using the change amount of the charging current with respect to the battery capacity, to a difference between the battery capacity of the secondary battery in the fully charged state and the battery capacity of the secondary battery at that time, and wherein in a case where the secondary battery is being charged with a constant current, the adjustment value is set to 1.