Devices and methods for protection of rechargeable elements
US6331763A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 22, 1999 |
| Grant date | Dec 18, 2001 |
| Priority date | — |
| Expiry date | Oct 22, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02J7/00309
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A protection circuit for use with a charger and a chargeable element, such as a rechargeable lithium ion battery, comprises a shunt regulator having a threshold ON voltage coupled in parallel across the chargeable element, and a temperature-dependent resistor, e.g., a positive temperature coefficient device, coupled in series between the charger and the chargeable element. The temperature dependent resistor is thermally and electrically coupled to the shunt regulator, wherein the first variable resistor limits current flowing through the shunt regulator if the current reaches a predetermined level less than that which would cause failure of the regulator, due to ohmic heating of the regulator.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.