Quick battery checker for lithium ion battery packs with impedance measuring method

We have developed a quick battery checker the Li-ion battery packs used in mobile phones. It checks for capacity deterioration by using an impedance-measuring method. Our previous measurements of the capacity and impedance at 1 kHz for various battery packs proved conclusively that there is a strong correlation between degraded capacity and impedance. The battery checker's design took into account the results we obtained from measuring impedances. We showed that the battery checker is highly accurate and fast.