Reversible automatic cell bypass circuit
US5258244A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 9, 1991 |
| Grant date | Nov 2, 1993 |
| Priority date | — |
| Expiry date | Dec 9, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02J7/0016
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A bypass circuit for a rechargeable battery cell has first and second normally open switches in parallel across the cell. The first switch, which can be a backward-biased rectifier, shunts the discharge current between the cell terminals if the battery cell fails but reopens if the battery cell recovers. The second switch shunts the charging current between the cell terminals if the battery cell fails but reopens if the cell recovers. The second switch can be a normally open FET transistor biased to close only when the cell voltage V.sub.C substantially exceeds a normal peak charging voltage V.sub.P. A rechargeable battery system in which the cells are series connected can incorporate a separate bypass circuit across each cell to enable the remaining good cells to continue charging and discharging even if a particular cell fails.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.