Method for rapid charge control in lithium batteries
US6859014B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 17, 2002 |
| Grant date | Feb 22, 2005 |
| Priority date | — |
| Expiry date | Dec 17, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02J7/04
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
This invention includes a method for charging lithium-based batteries. Battery type is identified by a charger by way of a third terminal. For nickel-based cells, the third terminal is coupled to a thermistor for sensing temperature. For lithium-based cells, the third terminal is coupled to the rechargeable cell disposed within the battery pack. If a nickel cell is identified, the cell is charged by conventional means. If a lithium cell is identified, the charger applies a full current until any serial elements disposed between the battery pack terminals and the cell reach a high impedance state. The charger then reduces the charging current to a low level for a predetermined time. After this time has elapsed, the charger then reapplies a high current. If the voltage across the serial elements remains low, charging continues. However, if the voltage across the serial elements exceeds a predetermined threshold, the charger then decrements the current by a predetermined amount.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.