Positive active material for electric primary cells
Abstract
Abstract A positive active material for electric primary cells, such as are used in electronic watches, is formed from a powder composed at least partially of grains having cores of silver peroxide completely surrounded by a layer of monovalent silver oxide and covered with a thin surface layer of metallic silver. The remainder of the powder, if any, comprises monovalent silver oxide grains, also covered with a thin surface layer of metallic silver. A process for making the material includes adding a reducing agent such as hydrazine to a powder having grains of less than 50 microns in diameter of essentially pure silver peroxide and reducing the silver peroxide to the point at which a thin layer of metallic silver forms on the surface of each powder grain. This point can be detected by a substantial reduction in electrical resistivity of the powder and occurs when approximately one-half of the original powder remains as silver peroxide.
Inventors
- 👤 Yves Jumel
Bibliographic Details
Claims Analysis
Total Claims: 8References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-11-13 | 1982-05-15 | 1982-11-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-11-13 | 1986-05-15 | 1986-11-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-11-13 | 1990-05-15 | 1990-11-14 | $7700.00 | Window Closed / Lapsed |