Patent · US Expired

Primary alkaline cell having a stable divalent silver oxide depolarizer mix

US4009056A · kind A · utility

26Cited by
3References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 15, 1976
Grant dateFeb 22, 1977
Priority date
Expiry dateMar 15, 1996

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01M6/12
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A primary alkaline cell having a stable divalent silver oxide depolarizer mix comprising a negative electrode (anode), a divalent silver oxide (AgO) depolarizer mix, a separator between said negative electrode and depolarizer mix, and an alkaline electrolyte. The surface of the depolarizer mix is treated with a mild reducing solution to form a reduced layer surrounding the mix, and the surface of the reduced layer adjacent to the separator is coated with a layer of silver. The reduced layer surrounding the depolarizer mix in combination with the layer of silver provides improved stability of the depolarizer mix in the alkaline electrolyte and a single voltage plateau during discharge of the cell. The primary alkaline cell is characterized by a maximum open circuit voltage of about 1.75 volts. The silver layer on the surface of the reduced layer surrounding the depolarizer mix can be formed by treating the reduced layer with a strong reducing solution to form a substantially continuous and electrolyte permeable silver layer, or alternatively, the silver layer may be formed by placing a silver screen, expanded silver metal, perforated silver foil or porous silver powder layer on top …

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.