Charging controller, rechargeable battery, electronic device, and control method

A charging controller, comprising:

• an internal resistance measurement unit configured to measure an internal resistance of a rechargeable battery multiple times over a charging period of the rechargeable battery;
• a detection unit configured to detect a peak of the internal resistance based on a change in the internal resistance measured by the internal resistance measurement unit;
• and
• an update unit configured to update a full charge capacity of the rechargeable battery referring to the peak of the internal resistance detected by the detection unit, wherein
• by temporarily stopping a charging current during the charging period of the rechargeable battery, the internal resistance measurement unit calculates the internal resistance of the rechargeable battery based on a difference between a voltage of the rechargeable battery before a stoppage and that of the rechargeable battery during the stoppage.

A control method in a charging controller, comprising:

• measuring an internal resistance of a rechargeable battery multiple times over a charging period of the rechargeable battery by an internal resistance measurement unit;
• detecting a peak of the internal resistance based on a change in the internal resistance measured by the internal resistance measurement unit by a detection unit;
• measuring a voltage of the rechargeable battery by a voltage measurement unit;
• and
• updating a full charge capacity of the rechargeable battery referring to the peak of the internal resistance detected by the detection unit by an update unit,
• wherein the internal resistance measurement unit raises a measurement frequency of the internal resistance when the voltage measured by the voltage measurement unit during the charging period of the rechargeable battery has reached a predetermined threshold value.