Double chromate compositions for use as positive active material in batteries
US4233374A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 13, 1979 |
| Grant date | Nov 11, 1980 |
| Priority date | — |
| Expiry date | Apr 13, 1999 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02E60/10
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Novel double chromate compositions having the general formula: EQU MBi(Cr.sub.x O.sub.y).sub.2, wherein M is silver or thallium and x is 1 and y is between about 3.7 and 4 or x is 2 and y is 7. Methods of making MBi(Cr.sub.x O.sub.y).sub.2 are characterized by reacting silver dichromate or thallium dichromate with a bismuth salt to provide equal numbers of silver or thallium atoms and bismuth atoms. Non-stoichiometric compositions wherein y is less than 4 and greater than or equal to about 3.7 are obtained by heating MBi(CrO.sub.4).sub.2 to a temperature between about 200.degree. C. and about 425.degree. C., the resulting product having an unchanged radio crystallographic structure. These double chromate compositions have particular utility in batteries as active positive material. Due to the steadiness of discharge voltage and duration of discharge of batteries employing these double chromate compositions, such batteries are especially adapted for use in clocks and in cardiostimulators or pacemakers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.