US Patent 7320842 - Fuel cell electrode catalyst with carbon nano-onion structure

http://www.freepatentsonline.com/7320842.html

This patent from Sanyo proposes a cheaper substitute for platinum in fuel cell electrode catalysts by using carbon layers formed around metal particles (metallofullerenes). Claim 1 reads:

1. A fuel cell, comprising: a cathode and an anode; and a layer comprising an electrode catalyst on the cathode or the anode. said electrode catalyst comprising graphitization-resistant carbon, at least a portion of the electrode catalyst having a random layer structure developed into lamination shell layers. said electrode catalyst being formed into a layer on at least one side of a solid polymer electrolyte film, wherein said random layer structure is a carbon nano-onion structure in which the lamination shell layers wind around metal particles.