| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a secondary battery system capable of estimating a capacity reduction rate caused by a negative electrode (more specifically, caused by a reduction of Li capable of contributing to a charging/discharging reaction in the negative electrode). <P>SOLUTION: A secondary battery system 6 includes: dQ/dV calculating means for calculating a value dQ/dV when charging a lithium ion secondary battery 100 which uses an external power source 46; peak voltage estimating means for estimating a battery voltage value X of a peak P1 appearing within a battery voltage range from a first battery voltage value V1 or more to a second battery voltage value V2 or less on a curved line V-dQ/dV, on the basis of a battery voltage V value and the value dQ/dV; and capacity reduction rate estimating means for estimating a capacity reduction rate Y of the battery 100 from the peak battery voltage value X acquired with peak voltage acquisition means, on the basis of data which shows a correlation between the battery voltage value X and the capacity reduction rate Y of the battery 100 at the peak P1 and which is stored in advance in the secondary battery system 6. <P>COPYRIGHT: (C)2013,JPO&INPIT |
