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:
Oct. 16, 2007
Filed:
Nov. 27, 2001
Arno Mattejat, Bubenreuth, DE;
Ottmar Voitlein, Lonnerstadt, DE;
Arno Mattejat, Bubenreuth, DE;
Ottmar Voitlein, Lonnerstadt, DE;
Siemens Aktiengesellschaft, Munich, DE;
Abstract
A leak in the membrane of a fuel cell leads to an uncontrolled and heat-generating reaction which can destroy the fuel cell. A method for recognition of a leak in a fuel cell is disclosed which leads to an automatic closing down of the fuel cell without a safety device. The anode gas chamber of the fuel cell is treated with a first test gas and the cathode gas chamber of the fuel cell is treated with a second test gas. The cell voltage of the fuel cell measured and the change with time in the cell voltage is monitored. A gas with a hydrogen content of 0.1 to 20 vol. % is used as first test gas and a gas with an oxygen content of 0.1 to 30 vol. % is used as second test gas.