The electrocatalysts in certain fuel cell systems can be poisoned by impurities in the fuel stream directed to the fuel cell anodes. Introducing a variable concentration of oxygen into the impure fuel stream supplied to the fuel cells can reduce or prevent poisoning without excessive use of oxygen. The variation may be controlled based on the voltage of a carbon monoxide sensitive sensor cell incorporated in the system. Further, the variation in oxygen concentration may be periodic or pulsed. A variable air bleed method is particularly suitable for use in solid polymer fuel cell systems operating on fuel streams containing carbon monoxide.
申请公布号
CA2292993(C)
申请公布日期
2004.05.11
申请号
CA19992292993
申请日期
1999.12.21
申请人
BALLARD POWER SYSTEMS INC.
发明人
VOHRA, RAJEEV;WILKINSON, DAVID P.;LAURITZEN, MICHAEL V.;KNIGHTS, SHANNA D.