The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 23, 2010
Filed:
Aug. 04, 2006
Dieter Melzner, Goettingen, DE;
Annette Reiche, Goettingen, DE;
Ulrich Maehr, Berlin, DE;
Suzana Kiel, Goettingen, DE;
Stefan Haufe, Goettingen, DE;
Dieter Melzner, Goettingen, DE;
Annette Reiche, Goettingen, DE;
Ulrich Maehr, Berlin, DE;
Suzana Kiel, Goettingen, DE;
Stefan Haufe, Goettingen, DE;
Volkswagen AG, Wolfsburg, DE;
Abstract
A membrane for fuel cells, which is characterized by a homogeneous absorption and good retention of doping agents, and which guarantees a high mechanical stability at high temperatures when doped. Such membranes consist of at least one polymer, whose nitrogen atoms are chemically bonded to a central atom of a derivative of a polybasic inorganic oxo acid. The membranes are produced from polymer solutions that are devoid of water and oxo acid derivatives, by heating the solution that has been introduced into a membrane mold until a self-supporting membrane has been formed and then by thermally regulating the latter. Inventive fuel cells having a membrane electrode assembly (MEA) that comprises a membrane of the invention and phosphoric acid as the doping agent have, for example, an impedance of 0.5-1 Ωcmat a measuring frequency of 1000 Hz and at an operating temperature of 160° C. and a gas flow for hydrogen of 170 mL/min and for air of 570 mL/min. They can be used as high-temperature polyelectrolyte membrane fuel cells for a working temperature of up to at least 250° C.