A cathode for a metal-air battery, the cathode including a mixed conductor; and first pores having a size of about 1 micrometer (m) or greater, wherein an amount of the first pores is about 30 volume percent (volume %) or greater, with respect to a total volume of pores in the cathode, and a total porosity of the cathode is about 50% or greater, based on a total volume of the cathode.

Ionomer membranes for fuel cells and related devices are described. An ionomer membrane may be configured with a plurality of anode-side protrusions and/or a plurality of cathode-side protrusions. A filler material(s) may be deposited into voids of an ionomer membrane. Example filler materials include, but are not limited to, platinum (Pt), palladium (Pd), cobalt (Co), nickel (Ni), gold (Au), silver (Ag), iridium (Ir), etc., and their alloys on carbon supports.

A membrane electrode assembly includes an electrolyte membrane stacked between different electrodes, wherein an ionomer layer of the electrolyte membrane comprises an adjacent electrode, a first layer having at least a same cross-sectional area as that of the adjacent electrode, a reinforcing layer and a second layer stacked at a side of the first layer, the second layer having at least the same cross-sectional area as that of the reinforcing layer.

Oxygen electrodes are provided, comprising a perovskite compound having Formula (I), Sr(Ti.sub.1-xFe.sub.x-yCo.sub.y)O.sub.3-wherein 0.90x0.40 and 0.02y0.30. Electrochemical devices comprising such oxygen electrodes are also provided, comprising a counter electrode in electrical communication with the oxygen electrode, and a solid oxide electrolyte between the oxygen electrode and the counter electrode. Methods of using such electrochemical devices are also provided, comprising exposing the oxygen electrode to a fluid comprising O.sub.2 under conditions to induce the reaction O.sub.2+4e.sup..fwdarw.2O.sup.2, or to a fluid comprising O.sup.2 under conditions to induce the reaction 2O.sup.2.fwdarw.O.sub.2+4e.sup..

This electrode catalyst of the present invention contains an electrically conductive material that supports a metal or a metal oxide, wherein electrical conductivity at 30 C. is 110.sup.13 Scm.sup.1 or greater.

The present specification relates to a method for manufacturing a membrane-electrode assembly, a membrane-electrode assembly manufactured therefrom, and a fuel cell including the same.

Disclosed are a polymer electrolyte membrane for fuel cells which has improved handling properties and mechanical strength by employing symmetric-type laminated composite films and a method for manufacturing the same.

The present invention relates to a transition metal nitride support, a method of manufacturing the same, a metal catalyst and a platinum-alloy catalyst including the transition metal nitride support, and manufacturing methods thereof. The manufactured transition metal support prevents corrosion of the support and aggregation of the platinum catalyst, thereby exhibiting high oxygen reduction catalytic activity. Also, strong metal-support interaction (SMSI) can be stabilized, thus improving the durability of the catalyst. The transition metal support includes large pores uniformly distributed therein, thereby increasing the amount of the catalyst supported and minimizing mass-transfer resistance in a membrane- electrode assembly, increasing the performance of a polymer electrolyte membrane fuel cell. The metal catalyst includes platinum particles loaded on the transition metal nitride support, thus exhibiting superior durability and activity. The manufactured platinum-alloy catalyst decreases the use of expensive platinum, thus generating economic benefits and improving the inherent oxygen reduction performance.

An electrode catalyst of the present invention contains an electrically conductive material carrying a metal or a metal oxide, and has an electrical conductivity at 30 C. of 110.sup.13 Scm.sup.1 or more.

A metal-air battery includes: a cathode formed of a co-continuous body having a three dimensional network structure formed by an integrated plurality of nanostructures having branches; a foil- or plate-like anode formed of a metal; a separator that absorbs a liquid, which is to be an electrolytic solution; and a foil- or plate-like current collector formed of a metal. The metal-air battery is formed with a wound structure in which the current collector, the cathode, the separator, the anode, and the separator are superimposed and wound in this order.