Method of coating one or more metal components of a fuel cell stack, component of a fuel cell stack and apparatus for coating one or more components of a fuel cell stack

A method of coating one or more components of a fuel cell stack, the method comprising the steps of:

• providing an uncoated metal component;
• etching said uncoated metal component;
• optionally depositing an adhesion layer on the etched uncoated metal component by means of one of a physical vapor deposition process, an arc physical vapor deposition process, an arc ion plating process, a sputtering process, and a Hipims process;
• and
• depositing a carbon coating on the adhesion layer if provided or directly on said etched uncoated metal component,
• wherein the carbon coating is deposited with a layer thickness selected in the range of 5 to 500 nm at a bias voltage of −0 to −200V
• wherein the carbon coating comprises an at least substantially hydrogen free DLC layer, deposited by one of an arc physical vapor deposition process, an arc ion plated process, and a Hipims process,
• wherein the at least substantially hydrogen free DLC layer comprises either a top layer having a dopant present therein, or includes a dopant throughout the at least substantially hydrogen free DLC layer,
• wherein the dopant is selected from the group of members consisting of titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, nitrogen, silicon and combinations of the foregoing.

A method of coating one or more components of a fuel cell stack, the method comprising the steps of:

• providing an uncoated metal component;
• etching said uncoated metal component;
• optionally depositing an adhesion layer on the etched uncoated metal component by means of one of a physical vapor deposition process, an arc physical vapor deposition process, an arc ion plating process, a sputtering process, and a Hipims process;
• and
• depositing a carbon coating on the adhesion layer if provided or directly on said etched uncoated metal component,
• wherein the carbon coating is deposited with a layer thickness selected in the range of 5 to 500 nm at a bias voltage of −0 to −200V
• wherein the carbon coating comprises an at least substantially hydrogen free DLC layer, deposited by one of an arc physical vapor deposition process, an arc ion plated process, and a Hipims process,
• wherein the at least substantially hydrogen free DLC layer comprises either a top layer having a dopant present therein, or includes a dopant throughout the at least substantially hydrogen free DLC layer,
• wherein a percentage of the dopant is 0.2 to 10 at % based on 100 at % of the at least substantially hydrogen free DLC layer respectively of the top layer comprising the dopant.

An apparatus for coating one or more components of a fuel cell stack, said apparatus being configured to carry out a method of coating said one or more components of a fuel cell stack, the method comprising the steps of:

• providing an uncoated metal component;
• etching said uncoated metal component;
• optionally depositing an adhesion layer on the etched uncoated metal component by means of one of a physical vapor deposition process, an arc physical vapor deposition process, an arc ion plating process, a sputtering process, and a Hipims process;
• and
• depositing a carbon coating on the adhesion layer if provided or directly on said etched uncoated metal component,
• wherein the carbon coating is deposited with a layer thickness selected in the range of 5 to 500 nm at a bias voltage of −0 to −200V and
• wherein the carbon coating comprises an at least substantially hydrogen free DLC layer, deposited by one of an arc physical vapor deposition process, an arc ion plated process, and a Hipims process, the apparatus being an inline coating system, comprising:
• a plurality of vacuum chambers arranged in a series one after another
• one or more cathodes arranged in at least some of the plurality of vacuum chambers;
• and
• one or more fixtures respectively configured to receive a plurality of the uncoated metal components, with the sides to be coated facing the one or more cathodes, the cathodes being a cathode for at least one of a physical vapor deposition process, an arc physical vapor deposition process, an arc ion plating process, a sputtering process, and a Hipims process;
• wherein said one or more fixtures are arranged to be moved linearly within the respective vacuum chamber and from vacuum chamber to vacuum chamber, wherein each vacuum chamber is configured to carry out a process, with the processes being selected from the group of members comprising:
• heating, evacuating, etching, depositing one or more adhesion layers, coating, removing and/or combinations of the foregoing.

A method of coating one or more components of a fuel cell stack, the method comprising the steps of:

• providing an uncoated metal component;
• etching said uncoated metal component;
• optionally depositing an adhesion layer on the etched uncoated metal component by means of one of a physical vapor deposition process, an arc physical vapor deposition process, an arc ion plating process, a sputtering process, and a Hipims process;
• and
• depositing a carbon coating on the adhesion layer if provided or directly on said etched uncoated metal component,
• wherein the carbon coating is deposited with a layer thickness selected in the range of 5 to 500 nm at a bias voltage of −0 to −200V
• wherein the carbon coating comprises an at least substantially hydrogen free DLC layer, deposited by one of an arc physical vapor deposition process, an arc ion plated process, and a Hipims process,
• wherein said method is conducted in a vacuum chamber and a temperature of said vacuum chamber is regulated to a temperature in the range of 160 to 250° C. during said step of coating said component with the carbon coating.