Abstract: A cylindrical metal-air cell has a cylindrical housing, an axially extending cylindrical air cathode adjacent an interior surface of the housing, and a plurality of elongate plenums defined between the oxygen electrode and the interior surface of the housing. Isolating passageway are positioned between the ambient environment and each of the plenums, and an air moving device is operable to force air through the isolating passageways and into at least one of the plenums. The air moving device may be a micromachined blower controlled by a circuit integrated into the housing of the blower.

Abstract: A cylindrical metal-air cell has a cylindrical housing, an axially extending cylindrical air cathode adjacent an interior surface of the housing, and a plurality of elongate plenums defined between the oxygen electrode and the interior surface of the housing. Isolating passageway are positioned between the ambient environment and each of the plenums, and an air moving device is operable to force air through the isolating passageways and into at least one of the plenums. The air moving device may be a micromachined blower controlled by a circuit integrated into the housing of the blower.

Abstract: A metal-air power supply which provides improved control over air flow is provided. The reactant air and cooling air inlets are separate from one another and isolated from the exhausted reactant and cooling portions of the air flow. The reactant air flow is limited to a volumetric flow rate sufficient to provide from about 3 to about 10 times the stoichiometric amount of oxygen necessary to produce a predetermined level of current from the cell, and a total volumetric flow rate of air sufficient so that the cooling portion of the air flow has a volumetric flow rate from about 10 to about 1000 times the volumetric flow rate of the reactant portion of the air flow is provided.

Abstract: A cathode cover for a metal-air cell of the type having an air cathode positioned along an external surface of a cell case provides for improved control over exposure of the air cathode to air. The cathode cover allows a sufficient amount of air to the air cathode for an adequate production of power from the cell but limits the amount of air to which the air cathode is exposed so as to prevent premature failure of the cell from flooding, drying out, or contamination. In addition, the cathode cover avoids the problems of point diffusion of oxygen through the air cathode and localized electrolytic reactions. The cathode cover includes a mask member defining a plurality of openings therethrough and forming at least one substantially unobstructed air chamber between the mask member and the air cathode. The mask member includes at least about three of the openings per square inch of the air cathode and the openings provide between about 0.001 and about 0.

Abstract: A bifunctional air-electrode for use in electrochemical energy cells discharges a satisfactory current on the first discharge cycle and operates for a relatively large number of charge-discharge cycles without gas forming between the electrolyte side of the air electrode and the electrolyte. The active layer of the electrode includes an oxygen reduction catalyst having a first oxygen evolution potential and an oxygen evolution catalyst having a second oxygen evolution potential less than the first oxygen evolution potential, the oxygen reduction catalyst being present in a greater concentration proximate the electrolyte side than proximate the air side and the oxygen evolution catalyst being present in a greater concentration proximate the air side than proximate the electrolyte side.