Ex Parte Ohma

Board of Patent Appeals and Interferences

Mar 23, 2012

10582222 (B.P.A.I. Mar. 23, 2012)

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.
10/582,222 06/08/2006 Atsushi Ohma 040356-0591 3852
22428 7590 03/26/2012
FOLEY AND LARDNER LLP
SUITE 500
3000 K STREET NW
WASHINGTON, DC 20007
EXAMINER
YANCHUK, STEPHEN J
ART UNIT PAPER NUMBER
1729
MAIL DATE DELIVERY MODE
03/26/2012 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 BOARD OF PATENT APPEALS
AND INTERFERENCES
____________

Ex parte ATSUSHI OHMA
____________

Appeal 20011-006638
Application 10/582,222
Technology Center 1700
____________

Before CHARLES F. WARREN, ROMULO H. DELMENDO, and
GRACE KARAFFA OBERMANN, Administrative Patent Judges.

OBERMANN, Administrative Patent Judge.

DECISION ON APPEAL
This is an appeal under 35 U.S.C. § 134 (2002) involving claims 11-
20 to a fuel cell stack. We have jurisdiction under 35 U.S.C. § 6(b).
We AFFIRM.
THE INVENTION
Claim 11, reproduced below, is illustrative of the subject matter on
appeal:
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Application 10/582,222

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11. A fuel cell stack comprising a plurality of stacked unit cells,
wherein each unit cell comprises:

a membrane electrode assembly in which gas diffusion
electrodes are disposed on each side of a polymer electrolyte
membrane; and

a separator comprising a plurality of ribs which contact the
membrane electrode assembly to realize a current collecting
function, and a plurality of gas passages formed between the
ribs for supplying a gas to the gas diffusion electrode,

the fuel cell stack comprises a first region and a second region,
with both the first region and the second region being located in
the interior of the fuel cell stack thereof, the first region having
a higher temperature than the second region, and

at least one of the gas passages, the ribs, and the gas diffusion
electrode is constituted such that a gas diffusion through the gas
diffusion electrode adjacent to the first region is improved
beyond the gas diffusion through the gas diffusion electrode
adjacent to the second region.

THE REJECTION
The Examiner relied on the following as evidence of unpatentability:
Knights US 2003/0077501 A1 Apr. 24, 2003
The following rejection is before us for review: Claims 11-20 stand
rejected under 35 U.S.C. § 102(b) as anticipated by Knights.
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Application 10/582,222

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ANALYSIS
The Appellant argues claims 11-20 as a group in the Appeal Brief
(App. Br. 10).1,2 We select claim 11 (see supra) as the representative claim.
Claims 12-20 stand or fall with claim 11. App. Br. 10. 37 C.F.R. §
41.37(c)(1)(vii).
The invention relates to a fuel cell stack that has a warmer first region
and a cooler second region in the interior of the fuel cell stack. Each of the
individual unit cells that form the stack includes a membrane electrode
assembly having a gas diffusion electrode and a gas separator. The gas
separator includes a plurality of gas passages and ribs. We determine that
claim 11 specifies a fuel cell stack comprising a plurality of stacked fuel
cells wherein at least one of the gas passages, the ribs, and the gas diffusion
electrode of at least one fuel cell is constituted to improve the gas diffusion
in the gas diffusion electrode adjacent to the warmer first region beyond the
gas diffusion in the gas diffusion electrode adjacent to the cooler second
region. See Spec., e.g., 3-12 and Figs. 1-6.
As an initial matter, the Appellant contends that the Examiner
misconstrued the claim 11 limitation that requires a first and a second region
in the interior of the fuel stack. The Appellant also argues that Knights is
not anticipatory because it fails to disclose two features of the claimed
invention, namely, (1) a first and a second region located in the interior of

1 Our decision will make reference to the Examiner’s Answer filed
November 10, 2010 (“Ans.”), the Appellant’s Brief filed August 2, 2010
(“App. Br.”) and the Appellant’s Reply Brief filed January 7, 2011 (“Reply
Br.”).
2 We have not considered dependent claims 15 and 16 which are not
separately argued in the Appeal Brief. See Reply Br. 2.
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Application 10/582,222

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the fuel cell stack defined by a temperature distribution, and (2) improved
gas diffusion in the gas diffusion electrode adjacent to the first region
beyond the gas diffusion through the gas diffusion electrode adjacent to the
second region. For the following reasons, we conclude that the Examiner
did not misconstrue claim 11, and that a fuel cell stack reading on the
disputed claim limitations is expressly or inherently described in Knight.

The Examiner Did Not Misconstrue Claim 11.
The Appellant argues that the Examiner misconstrued the claim 11
limitation that requires a fuel cell stack comprising “a first region and a
second region . . . located in the interior of the fuel cell stack.” Specifically,
the Appellant contends that the Examiner misconstrued the phrase “in the
interior of” to require that the second region be situated within the interior of
the first region (App. Br. 8-9). We are not persuaded. The Examiner found
that “[i]n any fuel cell, the inlet and outlet will have infinitesimal
characteristic changes including temperature and pressure” and that these
characteristics, within a unit cell, define “a first and second region” (Ans. 6-
7). Furthermore, the Examiner, in the course of applying Knights, provided
examples of first and second regions within a fuel cell wherein the second
region is not situated within the interior of the first region (see Ans. 4-5).
On this record, we reject the Appellant’s contention that the Examiner
misconstrued claim 11. We thus turn to the question whether Knights
anticipates the claim.
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Application 10/582,222

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Knights inherently describes “a first region and a second region”
defined by a temperature distribution as required by claim 11.

The Appellant argues that Knights does not disclose “a first region
and a second region” located in the interior of a fuel cell stack defined by a
temperature distribution as required by claim 11 (App. Br. 9). The Examiner
found that “[t]emperature is dependent on the systems [sic] state of reactant
flow” and that the temperature will vary in at least five regions across the
surface of a unit cell during the normal operation of any fuel cell stack (Ans.
4-5, 7). On that basis, the Examiner reasonably found that certain regions
along the surface of the unit cells of Knights “are inherently going to be
lower temperature than” certain other regions (Ans. 5), and that any of these
can reasonably “be interpreted as a first and second region” (Ans. 7).
The Appellant does not address or refute the Examiner’s finding that
two regions defined by a temperature distribution are inherently described in
Knights (Reply Br. 1). The entirety of Appellant’s rebuttal on this point
consists of a single conclusory sentence: “Knights simply does not disclose
a ‘first region’ and a ‘second region.’” (App. Br. 9; Reply Br. 1). Where no
persuasive argument or evidence as to error has been brought forward by the
Appellant, we affirm the Examiner’s conclusion that Knights inherently
discloses a warmer first region and a cooler second region as specified in
claim 11.
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Application 10/582,222

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Knights inherently describes a fuel cell stack in which the gas
passages of a fuel cell are constituted so that gas diffusion through a
gas diffusion electrode adjacent a warmer first region is beyond the
gas diffusion through the gas diffusion electrode adjacent the cooler
second region as required by claim 11.

Claim 11 requires that at least one of the gas passages, the ribs, and
the gas dispersion electrode of a fuel cell is constituted such that gas
diffusion is improved in the warmer first region. There is agreement that
Knights describes widening the gas passages in the outlet region of the unit
cell to improve gas diffusion compared to the inlet region. See App. Br. 9
(admitting that Knights “increases the width of the flow passage at the outlet
as compared with the inlet”); see Ans. 4-5, citing, e.g., Knights Fig. 4A.
Widening the gas passages adjacent to the warmer first region is one of the
ways in which gas dispersion is improved according to the Appellant’s
invention. See Spec. at 4:23-26 and Claim 11.
The Appellant observes that Knights widens the gas passages at the
outlet in order “to provide greater access to the catalyst layer and better
water removal at the outlet” but contends that Knights fails to relate the gas
passage “structure with the temperature distribution in the fuel cell stack”
(Reply Br. 2). The Examiner described in detail the inherent temperature
distribution across the surface of a unit cell during the normal operation of
any fuel cell stack (Ans. 5). The Examiner further provided at least one
example in which, during steady state operation, the region near the outlet
(identified as Section D in the Examiner’s Answer) is warmer than the
region near the inlet (identified as Section B in the Examiner’s Answer)
(Ans. 5). We see no error in the Examiner’s conclusion that Knights
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inherently teaches constituting the gas passages adjacent to a warmer first
region (the region near the outlet) in a way that improves the gas diffusion
compared to the cooler second region (the region near the inlet).
We agree with the Examiner that Knights describes as a matter of fact
each and every limitation of claim 11, either expressly or under the
principles of inherency, in a manner sufficient to have placed one skilled in
the art in possession of the invention. See, e.g., In re Schreiber, 128 F.3d
1473, 1477 (Fed. Cir. 1997), and cases cited therein.
No persuasive argument or evidence as to error having been made, we
affirm the Examiner’s rejection of claims 11-20 as anticipated by Knights.

CONCLUSION
The rejection of claims 11-20 under § 102(b) is AFFIRMED.
No time for taking any action connected with this appeal may be
extended under 37 C.F.R. § 1.136(a)(1)(iv).

AFFIRMED

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