Patent · US Expired

Metal-air cathode can, and electrochemical cell made therewith

US5795667A · kind A · utility

29Cited by
6References
54Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 19, 1995
Grant dateAug 18, 1998
Priority date
Expiry dateSep 19, 2015

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02E60/10
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

This invention pertains to metal-air electrochemical cells wherein one or more air entry ports is located in the bottom of the cathode can, to provide for entry of oxygen-rich air into the cathode can, where the oxygen participates in the chemical reaction whereby the cell produces electrical energy. In this invention, multiple small air entry ports are provided. Generally, the use of multiple ports distributed over the bottom of the cathode can, opposite the reaction surface of the cathode assembly, while not increasing the overall open area of the ports, results in an increase in the ratio of the cell limiting current to the rate at which moisture is lost from the cell. Accordingly, moisture loss as a function of electrical energy produced, is reduced. Preferred embodiments of the air entry ports have a stepped cross-sectional opening that provides a larger diffusion area controlling diffusion of air into and out of the cell through a covering tab prior to the cell being put into use, and a smaller untabbed diffusion area controlling diffusion of air into and out of the cell when the cell is in use.

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