摘要 |
A circuit for charging a lithium-ion battery and a technique for charging the battery are described. The battery charger takes into account the electrical series resistance (ESR) of the battery. The charger contains a compensation circuit which outputs the battery terminal voltage minus the expected voltage drop across the ESR of the battery. This resulting voltage is then applied to the sense terminals of the power supply. The voltage applied to the sense terminals of the power supply is, thus, representative of the active electrode voltage (AEV) of the battery. The power supply then provides sufficient charging current to maintain the voltage at the sense terminals at a preset voltage limit. Using this technique, the lithium-ion battery is charged to within 99.5% of its full charge in about half of the time required by the prior art.
|