Ex Parte Gould et al

Patent Trial and Appeal Board

Dec 7, 2016

12831382 (P.T.A.B. Dec. 7, 2016)

United States Patent and Trademark Office
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O.Box 1450
Alexandria, Virginia 22313-1450
www.uspto.gov
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
99590-US2 2329
EXAMINER
PARK, LISA S
ART UNIT PAPER NUMBER
1729
MAIL DATE DELIVERY MODE
12/831,382 07/07/2010
26384 7590 12/08/2016
NAVAL RESEARCH LABORATORY
ASSOCIATE COUNSEL (PATENTS)
CODE 1008.2
4555 OVERLOOK AVENUE, S.W.
WASHINGTON, DC 20375-5320
Benjamin D. Gould
12/08/2016 PAPER
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte BENJAMIN D. GOULD, KAREN SWIDER LYONS, and
OLGA A. BATURINA
Appeal 2015-005469
Application 12/831,382
Technology Center 1700
Before DONNA M. PRAISS, MONTE T. SQUIRE, and
JEFFREY R. SNAY, Administrative Patent Judges.
SNAY, Administrative Patent Judge.
DECISION ON APPEAL1
Appellants2 appeal under 35 U.S.C. § 134(a) from the Examiner’s
decision rejecting claims 1—9 and 13—15. We have jurisdiction under
35 U.S.C. § 6(b).
We reverse.
1 We cite to the Specification (“Spec.”) filed Jul. 7, 2010; Final Office
Action (“Final Act.”) dated Apr. 9, 2014; Examiner’s Answer (“Ans.”); and
Appellants’ Appeal Brief (“App. Br.”) and Reply Brief (“Reply Br.”).
2 Appellants identify The Government of the United States of America, as
represented by the Secretary of the Navy, as the real party in interest. App.
Br. 2.
Appeal 2015-005469
Application 12/831,382
BACKGROUND
The subject matter on appeal relates to a method for recovering
performance of a catalyst-containing cathode in a fuel cell. Spec. 1. Sole
independent claim 1 is illustrative:
1. A method of improving the electrical performance of an
operating fuel cell catalyst-containing cathode in a fuel cell
connected to an electrical load comprising:
stopping the flow of air to the cathode;
operating the fuel cell with the load connected to
consume oxygen at the cathode, leaving humidified nitrogen at
the cathode until the fuel cell produces a current below a
current threshold and a voltage less than a voltage threshold;
disconnecting the load from the fuel cell;
connecting a potentiostat to the fuel cell;
cycling an applied voltage, current, or power to the fuel
cell one or more times while the cathode is in contact with the
humidified nitrogen;
disconnecting the potentiostat from the fuel cell;
reconnecting the load to the fuel cell; and
resuming the flow of air to the cathode.
App. Br. 8 (Claims App’x) (emphasis added to highlight the key
recitation in dispute).
2
Appeal 2015-005469
Application 12/831,382
REJECTION
The Examiner maintained the following ground of rejection:3
Claims 1—9 and 13—15 stand rejected under 35 U.S.C. § 103(a)
as unpatentable over Donahue,4 Mohtadi,5 and Colbow.6
OPINION
In reaching the Rejection, the Examiner found that Donahue discloses
regenerating performance of a fuel cell by stopping the flow of oxidant gas
(air) to the cathode side of the fuel cell to reduce the cathode potential, but
fails to teach cycling voltage, current or power applied to the fuel cell. Final
Act. 2—3. For that feature, the Examiner relied on Mohtadi, finding that
Mohtadi discloses a fuel cell recovery method in which a voltage applied to
a fuel cell cathode is cycled “under nitrogen gas.” Id. at 3. The Examiner
reasoned that it would have been obvious to “include the application of a
cycled voltage in the method of Mohtadi to the fuel cell recovery method of
Donahue to be able to rejuvenate the cathode despite extensive poisoning.”
Id. at 5.
Appellants principally argue that neither Donahue nor Mohtadi
teaches cycling an applied voltage, current, or power while the cathode is in
contact with the humidified nitrogen which remains after operating the fuel
cell while the air flow is stopped. App. Br. 4—5. Particularly, Appellants
point out that “Mohtadi teaches the use of cyclic voltammetry with the
3 Final Act. 2—6; Ans. 2—6.
4 US 6,399,231 Bl, issued Jun. 4, 2002 (“Donahue”).
5 R. Mohtadi, Assessing Durability of Cathodes Exposed to Common Air
Impurities, 138 J. Power Sources 216—225 (2004) (“Mohtadi”).
6 US 6,472,090 Bl, issued Oct. 29, 2002 (“Colbow”).
3
Appeal 2015-005469
Application 12/831,382
cathode under flowing pure nitrogen.” Id. at 4 (citing Mohtadi). There,
Mohtadi explains that cyclic voltammetry was performed “while flowing N2
on the cathode” (Mohtadi, rt. col., 1st full para.), and that “high purity N2”
was used {id. at It. col., 1st full para.). Appellants contend that even if
Mohtadi’s cyclic voltammetry technique were applied in Donahue’s method,
any residual humidified nitrogen in contact with the fuel cell cathode “would
be immediately replaced by pure nitrogen.” App. Br. 5.
In response, the Examiner interpreted the phrase, “cycling an applied
voltage,” in claim 1 as “initiating a potentiostat to cycle the applied
voltage.” Ans. 7. Under that interpretation, the Examiner found that there
inherently would be residual humidified nitrogen in contact with the cathode
“at least when the cycling is initiated, which meets the claim limitation.” Id.
Appellants persuasively argue, Reply Br. 1—2, that the foregoing claim
interpretation is unreasonable. Claim 1 recites, “cycling an applied voltage,
current, or power to the fuel cell one or more times while the cathode is in
contact with the humidified nitrogen.” (Emphasis added). As the Examiner
acknowledged, one cycle would involve sweeping the applied voltage from a
starting voltage to a different ending voltage and returning to the starting
voltage. See Ans. 7 (“[A] potential is applied starting from a negative
potential to a positive potential and back to the negative potential in one
‘sweep’.”). The claim expressly requires that at least one such cycle occurs
“while the cathode is in contact with the humidified nitrogen,” particularly,
the same humidified nitrogen which is left at the cathode as a result of
operating the fuel cell for a period of time after stopping the flow of air to
the cathode. The Examiner’s different interpretation is contrary to the
express language of the claim and, therefore, improper.
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Appeal 2015-005469
Application 12/831,382
The Examiner alternatively found that “the skilled artisan would find
it reasonable to expect the humidified nitrogen to be in the cathode
compartment and contacting the cathode for a long enough time to
accommodate a single cycle ... of the potentiostat based on the flow rate of
added nitrogen of Mohtadi and the scan rate of the potentiostat.” Ans. 8.
However, Appellants persuasively argue that Mohtadi does not provide a
flow rate of added nitrogen. Reply Br. 2; see Mohtadi 217, section 2
(Experimental). The Examiner has not identified any evidence of record or
technical reasoning to support the otherwise conclusory statement that
humidified nitrogen would contact Donahue’s cathode over the course of at
least one cycle of Mohtadi’s cyclic voltammetry under flowing nitrogen.
On this record, we are persuaded that the Examiner erred in finding
that the combination of Donahue and Mohtadi teaches or inherently results
in cycling an applied voltage, current, or power while the cathode is in
contact with the humidified nitrogen which results from operating the fuel
cell after the air flow is stopped. That deficiency is not remedied by the
additional prior art cited by the Examiner in the Final Rejection.
Accordingly, we do not sustain the Rejection of claim 1. Because each of
claims 2—9 and 13—15 depend directly from claim 1, we reverse the rejection
of the dependent claims for the same reason.
DECISION/ORDER
The Examiner’s rejection of claims 1—9 and 13—15 under 35 U.S.C.
§ 103(a) is reversed.
REVERSED
5