| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To accurately detect a degree of deterioration of a battery having a great polarization resistive component and deteriorating when left in no use. <P>SOLUTION: A degree of deterioration is calculated in the way of: measuring closed circuit voltage and a charging current during charging, first open circuit voltage when a first waiting time passes after turning a charging control switch off after measuring the closed circuit voltage, and second open circuit voltage when a second waiting time longer than the first waiting time passes; calculating a direct current resistive component, based on a voltage difference between the closed circuit voltage and the first open circuit voltage and the charging current; calculating a polarization resistive component, based on a voltage difference between the first open circuit voltage and the second open circuit voltage and the charging current; and subtracting initial internal resistance from the sum of the direct current resistive component and the polarization resistive component. It is desirable to turn the charging control switch off when the closed circuit voltage is not lower than rated voltage during charging, and then measure the first open circuit voltage when the first waiting time passes and the second open circuit voltage when the second waiting time longer than the first waiting time passes. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
