Battery capacity estimation method, and battery module and electronic product using the same

A battery capacity estimation method being applied to a battery module comprising a battery and a control system and detecting the battery of the battery module, wherein:

• the control system comprises a detection unit, a storage unit and a processing unit;
• the storage unit stores OCV information and multiple design capacities, and the OCV information comprises an OCV table or a function corresponding to different temperatures;
• and
• the battery capacity estimation method comprises:
• measuring, by the detection unit, an OCV and a temperature of the battery when the processing unit knows that the battery has been charged to a fully charged state for a predetermined period and entered a rest state;
• obtaining, by the processing unit, a SOC of the battery according to both of the OCV and the temperature of the battery corresponding to the OCV table or the function;
• obtaining a design capacity corresponding to the temperature and the multiple design capacities and the temperature;
• and
• calculating, by the processing unit, a Q T of the battery according to the design capacity corresponding to the temperature and the SOC, wherein the QT represents an inherent capacity at the temperature.