Patent ID: 7974797
Filing Date: 2011-07-05
Classification: G01R

Abstract:
1. A method of confirming battery charge amount and degradation state, comprising: a first step of measuring or calculating at a plurality of battery temperatures a cycle test battery in respect of battery internal and surface temperatures and measurement values at least two selected from battery open voltage, current and voltage during discharge, and current and voltage during charging at prescribed time intervals substantially until an end of life of the cycle test battery; a second step of using the measured or calculated values to generate determination tables showing relationships in each case between charge amounts and degradation states at said prescribed time intervals; a third step of measuring or calculating a subject battery in respect of said battery internal and surface temperatures and said at least two measurement values selected from battery open voltage, current and voltage during discharge, and current and voltage during charging; and a fourth step of comparing determination table values with said battery internal and surface temperatures and each of the measured or calculated values of the subject battery to make a primary confirmation of a present subject battery charge amount and degradation state in accordance with determination table locations of matching values and to make an overall confirmation of results of the primary confirmation based on an appearance ratio of said determination table locations, thereby estimating said present subject battery charge amount and degradation state, wherein the fourth step is carried out by a computer and a display shows the estimated present subject battery charge amount and degradation state.