Thermally responsive battery charger
US5013993A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 29, 1988 |
| Grant date | May 7, 1991 |
| Priority date | — |
| Expiry date | Aug 29, 2008 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02J7/007194
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A battery charger 10 includes a capacitor 20 which establishes a level of current sufficient to fast charge in one-hour a battery 18 having from one to twenty cells. An SCR 16 is controlled by a timer 42 to initially delay the supply of current while determining whether the battery 18 is hot or cool. If battery 18 is cool, charger 10 proceeds to fast charge the battery. After battery 18 is fully charged, the battery heats to a temperature where a NTC thermistor 58 responds to trigger a second timer 52 which controls SCR 16 to stop the fast charging operation. Charger 10 is then controlled to prevent the charger from thereafter re-entering a fast charge mode. If battery 18 is initially hot, charger 10 is controlled to further delay the initiation of a fast charge operation until the battery cools to or below the charge-start temperature. A second NTC thermistor 90 is provided to compensate for the potential effect on the operation of thermistor 58 in response to temperature levels emanating from any environment other than from battery 18.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.