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:
Sep. 28, 2004
Filed:
Feb. 14, 2002
Zhaoyu Wang, Vancouver, CA;
Ross W. Johnston Bailey, Vancouver, CA;
Graham E. Hill, Vancouver, CA;
Hong The Nguyen, Vancouver, CA;
Ballard Power Systems Inc., Burnaby, CA;
Abstract
A fuel cell resistance test system includes a contact head having a plurality of spaced electrical contacts for contacting multiple ones of the fuel cells composing the stack. In one embodiment, a plurality of selectively actuable switches produce a short between respective pairs of adjacent ones of the electrical contacts. A processor opens each of the switches, one at a time in succession, to apply a defined voltage from a voltage source, successively across pairs of adjacent ones of the electrical contacts. A current sensor measures a resulting current and the processor or other computer determines whether a short exists based on the magnitude of the defined voltage and the magnitude of the resulting current. Alternatively, the test system may include a current source and a voltage sensor.