Fuel cell electrode assembly with hydrophobic polymer loading
CA 2052221 C · Owner: Epp, Danny G. · Inventors: Epp, Danny G.; Dircks, Kenneth W.; Watkins, David S.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A hydrophobic porous electrically conductive material comprises a porous electrically conductive sheet material and a hydrophobic polymer, such as polytetra-fluoroethylene, impregnated in the sheet material. The ratio of the hydrophobic polymer to the sheet material is in the range of about 2% to about 14% by weight and preferably about 4% to about 8% by weight. The most preferred value is about 6% of polytetrafluoroethylene to carbon sheet material by weight. In another embodiment the polytetrafluoroethylene loading on the electrode acting as an anode is at least about two times higher than for the cathode.
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed September 25, 1991 and granted April 11, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended September 25, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 25, 2013.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.