DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
Claims 1-17 are rejected under 35 U.S.C. 103 as being unpatentable over Salvador et al. (US 8,195,407) in view of Schmidt (US 2010/0129688).
Regarding claims 1, 9, 14, Salvador discloses a method for estimating nitrogen levels in fuel cells (abstract), the method comprising: determining an electrical current output ( compressor 14 in fig. 1) of a fuel cell stack configured to generate electrical current from hydrogen ( fig. 1; col. 4, lines 52-67; col. 5, lines 1-20); determining an efficiency level of the fuel cell stack ((stack internal volume much greater than the plumbing volume in col. 6, lines 2-3); determining a nitrogen diffusion rate based on the determined electrical current output and the determined efficiency level (col. 1, lines 17-26; col. 2, lines 46-67); and determining a nitrogen concentration in the based on the determined nitrogen diffusion rate. (fig. 1-fig. 2; abstract; col. 1, lines 17-26; col. 2, lines 46-67).
Salvador discloses all the limitations set forth above but fails to explicitly disclose provided in a hydrogen recirculation loop; hydrogen recirculation loop.
However, Schmidt discloses provided in a hydrogen recirculation loop (page 2, [0023]); hydrogen recirculation loop (page 2, [0023]).
Therefore, it would have been obvious to one of the ordinary skill in the art at the time the invention was first filed to incorporate the feature of Schmidt within the system of Salvador in order to remove the impurities on the fuel cell system thereby improving the reliability of the system.
Regarding claims 2, 10, Salvador and Schmidt disclose all the limitations set forth in claim 1 and Schmidt further discloses determining that the determined nitrogen concentration has exceeded a predetermined nitrogen concentration threshold level; and purging the hydrogen recirculation loop based on the determined exceeding of the predetermined nitrogen concentration threshold level (page 2, [0023-0026]).
Regarding claims 3, 11, Salvador discloses wherein the efficiency is determined based on the
determined nitrogen concentration (col. 1, lines 17-25).
Regarding claims 4, 12, Salvador discloses wherein determining a nitrogen concentration in the
hydrogen recirculation loop based on the determined nitrogen diffusion rate further
comprises determining an integral of the determined nitrogen diffusion rate over time,
wherein the determined nitrogen concentration is based on the determined integral (col. 1, lines 17-67).
Regarding claims 5, 13, Salvador discloses wherein the determined nitrogen diffusion rate is further
based on a predetermined nitrogen coefficient value, a predetermined membrane pressure gradient value, and a predetermined diffusion concentration value (col. 1, lines 17-67; col. 2, lines 46-64)..
Regarding claim 6, Salvador and Schmidt disclose all the limitations set forth in claim 1 and Schmidt further discloses controlling a recirculation flow rate of hydrogen based on the determined electrical current output (page 2, [0023-0024]).
Regarding claim 7, Salvador and Schmidt disclose all the limitations set forth in claim 1 and Schmidt further discloses flowing the hydrogen and recirculation gasses from the hydrogen recirculation loop through a jet pump configured to urge flow of the recirculation gasses based on the flow of hydrogen (page 2, [0023-0025]).
Regarding claim 8, Salvador discloses operating at least one of a water separator or a nitrogen separator based on the determined nitrogen concentration (col. 1, lines 17-62).
Regarding claims 15-17, Salvador and Schmidt disclose all the limitations set forth in claim 9 and Schmidt further discloses a hydrogen inlet configured to receive pressurized hydrogen;
at least a portion of a hydrogen recirculation loop; a loop outlet configured to fluidically connect the hydrogen recirculation loop to an anode inlet of an anode manifold of a fuel cell stack; and
a loop inlet configured to fluidically connect the hydrogen recirculation loop to an
anode outlet of the anode manifold (page 2, [0023-0026]).
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Lang et al. (US 2012/0052408) discloses membrane………cell.
Kamihara (US 2005/0244686) discloses fuel cell system.
Sawyer (US 6,569,549) discloses method…..cell power plant.
Wang et al. (US 11,251,443) discloses fuel cell system….power plant.
Baumann et al. (US 2009/0263683) discloses method….operation.
Pinkerton et al. (US 2006/0029529) discloses pressurized…cells.
Kaczur et al. (US 10,329,676) discloses method……electrode.
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DP
July 28, 2026
/DANIEL PREVIL/ Primary Examiner, Art Unit 2685
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