Patent ID: 8664960
Filing Date: 2014-03-04
Classification: G01R

Abstract:
1. A device for estimating charged state of a secondary battery provided with a detector capable of detecting input/output current, an output voltage and battery temperature, comprising: first estimating means for estimating the remaining capacity of said secondary battery by calculating amount of change in said remaining capacity based on an integrated value of said input/output current; second estimating means for estimating the remaining capacity of said secondary battery based on a battery model using said input/output current, said output voltage and said battery temperature as input variables; timer means for measuring duration of continuous execution of the estimation of remaining capacity by said first estimating means; and selecting means for selecting one of said first and second estimating means for estimating said remaining capacity, based on determination as to whether said input/output current is within a prescribed range that allows use of the battery model or not and on said duration of continuous execution obtained by said timer means.