Bipolar plate of an energy converter, comprising a metallic substrate and a layer system applied at least in partial regions of the surface of the substrate, wherein the layer system comprises a top layer and a backing layer system, the top layer consisting of a homogeneous or heterogeneous solid metallic solution having a metal lattice which either, in a first alternative, contains a first chemical element from the group of noble metals in the form of iridium as a host metal and, dissolved in the metal lattice of the host metal, further contains at least one further non-metallic chemical element from the group comprising nitrogen, carbon, boron, fluorine, hydrogen, wherein the at least one non-metallic chemical element is present in a concentration in the range from 0.1 at. % to 65 at. % in the top layer, or in a second alternative contains a first chemical element from the group of noble metals in the form of iridium and a second chemical element from the group of noble metals in the form of ruthenium as host metals and containing dissolved in the metal lattice of the host metal at least one further non-metallic chemical element from the group comprising nitrogen, carbon, boron, fluorine, hydrogen, wherein the at least one non-metallic chemical element is present in a concentration in the range from 0.1 at. % to 65 at. % in the top layer, wherein the top layer in the first alternative. a) comprises more than 35 at. % iridium and furthermore carbon; or b) comprising more than 35 at. % iridium and further comprising carbon and trace amounts of hydrogen; or c) comprises more than 35 at. % iridium and furthermore carbon and fluorine, optionally furthermore trace amounts of hydrogen; and wherein the top layer in the second alternative. d) comprises in total more than 35 at. % iridium and ruthenium and furthermore carbon; or e) comprising in total more than 35 at. % iridium and ruthenium and further comprising carbon and trace amounts of hydrogen; or f) comprises in total more than 35 at. % iridium and ruthenium and furthermore carbon and fluorine, optionally furthermore trace amounts of hydrogen. contains a first chemical element from the group of noble metals in the form of iridium as a host metal and, dissolved in the metal lattice of the host metal, further contains at least one further non-metallic chemical element from the group comprising nitrogen, carbon, boron, fluorine, hydrogen, wherein the at least one non-metallic chemical element is present in a concentration in the range from 0.1 at. % to 65 at. % in the top layer, or in a second alternative contains a first chemical element from the group of noble metals in the form of iridium and a second chemical element from the group of noble metals in the form of ruthenium as host metals and containing dissolved in the metal lattice of the host metal at least one further non-metallic chemical element from the group comprising nitrogen, carbon, boron, fluorine, hydrogen, wherein the at least one non-metallic chemical element is present in a concentration in the range from 0.1 at. % to 65 at. % in the top layer, wherein the top layer in the first alternative. a) comprises more than 35 at. % iridium and furthermore carbon; or b) comprising more than 35 at. % iridium and further comprising carbon and trace amounts of hydrogen; or c) comprises more than 35 at. % iridium and furthermore carbon and fluorine, optionally furthermore trace amounts of hydrogen; and wherein the top layer in the second alternative. d) comprises in total more than 35 at. % iridium and ruthenium and furthermore carbon; or e) comprising in total more than 35 at. % iridium and ruthenium and further comprising carbon and trace amounts of hydrogen; or f) comprises in total more than 35 at. % iridium and ruthenium and furthermore carbon and fluorine, optionally furthermore trace amounts of hydrogen. a) comprises more than 35 at. % iridium and furthermore carbon; or b) comprising more than 35 at. % iridium and further comprising carbon and trace amounts of hydrogen; or c) comprises more than 35 at. % iridium and furthermore carbon and fluorine, optionally furthermore trace amounts of hydrogen; and wherein the top layer in the second alternative. d) comprises in total more than 35 at. % iridium and ruthenium and furthermore carbon; or e) comprising in total more than 35 at. % iridium and ruthenium and further comprising carbon and trace amounts of hydrogen; or f) comprises in total more than 35 at. % iridium and ruthenium and furthermore carbon and fluorine, optionally furthermore trace amounts of hydrogen.