Overdischarge protection in high-temperature cells and batteries
US4935316A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 25, 1989 |
| Grant date | Jun 19, 1990 |
| Priority date | — |
| Expiry date | Jul 25, 2009 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02E60/10
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Overdischarge indication and protection is provided in a lithium alloy - metal sulfide, secondary electrochemical cell and batteries of such cells through use of a low lithium activity phase that ordinarily is not matched with positive electrode material. Low lithium activity phases such as Li.sub.0.1 Al.sub.0.9 and LiAlSi in correspondence with positive electrode material cause a downward gradient in cell voltage as an indication of overdischarge prior to damage to the cell. Moreover, the low lithium activity phase contributes lithium into the electrolyte and provides a lithium shuttling current as overdischarge protection after all of the positive electrode material is discharged.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.