Secondary electrochemical cell
US5591543A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 15, 1995 |
| Grant date | Jan 7, 1997 |
| Priority date | — |
| Expiry date | May 15, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02E60/10
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The invention relates to novel cathodes for secondarylithium cells and to lithium cells which contain such cathodes. The secondary cells can be charged and discharged substantially more times than corresponding cells which contain conventional LiCoO.sub.2 type cathodes. The cathodes are based on crystalline compounds of the Li.sub.1 x M.sub.x/2 CoO.sub.2 type. One of the aspects of the invention is a process for the production of such crystalline cathodes, where M is selected from calcium, strontium, barium and magnesium and where the content of such bivalent cation M in the crystal is from about 0.1 weight-% to about 10 weight-%, preferably 0.2 to 5 weight-%. The novel crystalline cathode compound is synthesized by a solid/solid reaction at elevated temperature, generally in the 700.degree. C. to about 900.degree. C. range. The cathode may be prepared from small crystals of such a compound, in combination with a compatible binder or conductive material, such as graphite.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.