Abstract: A plate, e.g. a bipolar plate, for fuel cells for (a) conducting current from the anode of one cell unit to the cathode of the adjacent cell unit and/or (b) distributing fluid which comprises a substrate with a coating of an electrocatalytically-active material comprising ruthenium oxide.

Abstract: Metal plates to be used in electrochemical cells, e.g. fuel cells, are treated by subjecting a surface or surfaces thereof to an electrical current in the presence of an acidic electrolyte, the alloy being stainless steel or one containing in excess of 14% by weight nickel, e.g. in excess of 15% by weight nickel.

Abstract: A plate, e.g. a bipolar plate, for fuel cells for (a) conducting current from the anode of one cell unit to the cathode of the adjacent cell unit and/or (b) distributing fluid which comprises a substrate with a coating of an electrocatalytically-active material comprising ruthenium oxide.

Abstract: An electrode which comprises a substrate of a valve metal or an alloy thereof having properties similar to those of the valve metal and a coating comprising an outer layer which comprises RuO.sub.2, an oxide of at least one non-noble metal and at least one other noble metal or oxide thereof and an intermediate layer having a composition different from that of the outer layer and which comprises RuO.sub.2 and an oxide of at least one non-noble metal. The electrode is particularly useful as an anode for an electrolytic cell, eg a chlor-alkali cell, it has a lifetime therein which is greater than the sum of the operational life-times of electrodes which comprise a valve metal substrate and which separately comprise one of the above layers which together form a part of the coating of that electrode.