Method of charging secondary battery, method of calculating remaining capacity rate of secondary battery, and battery pack

Abstract

PROBLEM TO BE SOLVED: To correctly detect full charge by further accurately measuring a charging capacity, in a charging method for a secondary battery obtained by combining an integration method and a voltage method that have conventionally been used.SOLUTION: The charging capacity (charging rate) is calculated by the integration method (current integration or power integration) from the start of charging to the vicinity of the full charge. The charging capacity is gradually shifted to a value calculated by the voltage method by adding thereto values obtained by both the calculation methods in accordance with a proportion multiplied by a voltage-method reliability coefficient by using a coefficient being a voltage-method reliability when the charging capacity reaches the vicinity of the full charging, and the integration method calculated value can be switched to the voltage method calculated value without an uncomfortable feeling, thus performing the correct full charge detection (charging rate calculation).

Description

technical field [0001] The invention relates to a storage battery charging method, a calculation method for the remaining capacity ratio of the storage battery and a battery pack. Background technique [0002] Currently, for many devices using batteries, a rechargeable storage battery is used at a user's home or the like and charged with a charging device. These devices are configured to indicate that charging is in progress or completed through the color of the light, flashing or liquid crystal display, or are configured to give an indication of the battery capacity to let the user know the approximate remaining usable time. [0003] The method of detecting the charging capacity and remaining capacity of the storage battery may include the integral method and the voltage method. In the integral method, the charging capacity is calculated by obtaining the integral of the current or power output, while in the voltage method, whether the battery voltage has been measured is ca...

AI Technical Summary

Problems solved by technology

If the current of the battery shows a small value, the voltage method provides high accuracy in capacity calculation, whereas if the above current shows a large value, it will change due to the fluctuation of the DC Imp (impedance) with the ambient temperature. Or the fluctuation of Imp inside the battery, etc., without obtaining an accurate open circuit voltage, which hinders the accurate calculation of battery capacity

Also, if the current of the battery shows a large value, the integral method provides high accuracy in capacity calculation, whereas it makes the integral error increase as the current decreases, resulting in less accurate capacity calculation

Images