Ex Parte Skala

Board of Patent Appeals and Interferences

Jun 5, 2012

11586257 (B.P.A.I. Jun. 5, 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.
11/586,257 10/25/2006 Glenn W. Skala GP-307407-FCAR-CHE 9177
65798 7590 06/05/2012
MILLER IP GROUP, PLC
GENERAL MOTORS CORPORATION
42690 WOODWARD AVENUE
SUITE 200
BLOOMFIELD HILLS, MI 48304
EXAMINER
THOMAS, BRENT C
ART UNIT PAPER NUMBER
1726
MAIL DATE DELIVERY MODE
06/05/2012 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 GLENN W. SKALA
____________

Appeal 2011-004530
Application 11/586,257
Technology Center 1700
____________

Before BRADLEY R. GARRIS, TERRY J. OWENS, and
PETER F. KRATZ, Administrative Patent Judges.

GARRIS, Administrative Patent Judge.

DECISION ON APPEAL

Appellant appeals under 35 U.S.C. § 134 from the Examiner's
rejections under 35 U.S.C. § 103(a) of independent claims 1, 11, and 16 as
unpatentable over Wexel (US 2004/0157098 A1, pub. Aug. 12, 2004) in
view of Sederquist (US 2004/0234829 A1, pub. Nov. 25, 2004) and of
remaining dependent claims 2-5, 7-10, 12-15, and 17-19 as unpatentable
over these references alone or further in view of other prior art of record.
We have jurisdiction under 35 U.S.C. § 6.
We REVERSE.
Appeal 2011-004530
Application 11/586,257

2
Appellant claims a fuel cell stack module 40 comprising a fuel cell
stack 42, a charge air cooler 62, and a water vapor transfer unit 60, wherein
the water vapor transfer unit receives a flow of cathode exhaust gas from the
fuel cell stack to provide humidification to humidify the cathode inlet air
(independent claims 1, 11, and 16; Figs. 2-3).
Representative claim 1 reads as follows:
1. A fuel cell stack module comprising:

a fuel cell stack;

a stack end unit coupled to and separate from the fuel cell stack as part
of an integrated assembly;

a charge air cooler positioned within the stack end unit; and

a water vapor transfer unit positioned within the stack end unit,
wherein the charge air cooler receives a cathode inlet airflow and reduces
the temperature of the cathode inlet airflow, said water vapor transfer unit
receiving the cooled cathode inlet airflow from the charge air cooler and
sending it to a cathode side of the fuel cell stack, wherein the water vapor
transfer unit receives a flow of cathode exhaust gas from the fuel cell stack
to provide humidification to humidify the cathode inlet air.

The Examiner finds that Wexel discloses a fuel cell stack module
comprising a fuel cell stack 300, a charge air cooler in the form of heat
exchanger 361, and a water vapor transfer unit which comprises water
supply line 372, spray nozzles 374a-d, and evaporative element 364 (Wexel
Fig. 3; Ans. para. bridging 3-4). The Examiner concedes that "Wexel . . .
does not disclose the module wherein the water vapor transfer unit receives a
flow of cathode exhaust gas from the fuel cell stack to provide the
humidification to humidify the cathode inlet air" (id. at 4). Regarding this
Appeal 2011-004530
Application 11/586,257

3
conceded deficiency, the Examiner finds that "Sederquist . . . teaches a water
vapor transfer unit ('gas-exchange humidifier' Fig. 1 (30), [0029]) in fluid
communication with an airstream supplied to the stack and a cathode
exhaust stream exiting the stack for transferring water vapor from the
cathode exhaust stream to the airstream [0016]" (id. at para. bridging 4-5).
In light of these findings, the Examiner concludes that it would have
been obvious
to replace the water vapor transfer unit of Wexel . . . with the
water vapor transfer unit of Sederquist . . . for purposes of
maintaining adequate water balance in the fuel cell system
(Sederquist . . . [0020]), thus removing water from the
cathode and preventing the cathode from flooding
(Sederquist . . . [0006])

(id. at 5).
Appellant acknowledges that Sederquist discloses a water vapor
transfer unit which receives humidity from a cathode exhaust gas but points
out that Sederquist does not teach the water vapor transfer unit in
combination with a charge air cooler1 as claimed (see, e.g., App. Br. 11).
Appellant argues that, as a consequence, Wexel and Sederquist would not
have suggested the charge air cooler and water vapor transfer unit
combination required by the independent claims such as the claim 1
arrangement wherein the charge air cooler is upstream of the water vapor
transfer unit (id.).

1 It is undisputed that the fuel cell system of Sederquist does not include a
charge air cooler. To the contrary, the inlet air is preheated rather than
cooled in Sederquist's system (see, e.g., para. [0028]).
Appeal 2011-004530
Application 11/586,257

4
In response, the Examiner states that Wexel shows the combination of
a charge air cooler and a water vapor transfer unit including the claim 1
arrangement wherein Wexel's heat exchanger (i.e., charge air cooler) is
upstream of the evaporative element (i.e., the final component of Wexel's
water vapor transfer unit) (Ans. para. bridging 23-24). Accordingly, the
Examiner concludes that Wexel and Sederquist would have suggested
replacing Wexel's water vapor transfer unit with Sederquist's water vapor
transfer unit to thereby result in a charge air cooler and water vapor transfer
unit as combined and arranged by the rejected claims including independent
claim 1 (id.).
The deficiency of the Examiner's position is that it lacks specificity
concerning the practical manner in which the teachings of these references
would have been combined so as to result in the fuel cell stack modules
defined by the independent claims. For example, the Examiner indicates
that the claim 1 arrangement would have been obtained by substituting the
gas-exchange humidifier 30 (i.e., the water vapor transfer unit) of
Sederquist's Figure 1 fuel cell system for Wexel's evaporative element 364
(i.e., the final component of Wexel's water vapor transfer unit). However,
the Examiner fails to provide any explanatory detail as to how this
substitution would have been implemented in a practical and realistic
manner. On its face, the relative sizes shown in Sederquist's Figure 1 system
reveal that it would not be possible to substitute a gas-exchange humidifier
of the type taught by Sederquist for the evaporative element 364 disposed
below heat exchanger 361 in the manifold 362 of Wexel's fuel cell stack 300
(see Wexel Fig. 3).

Appeal 2011-004530
Application 11/586,257

5
These circumstances lead us to determine that the Examiner has failed
to carry the burden of establishing a prima facie case of obviousness for the
fuel cell stack modules defined by the independent claims and
correspondingly the dependent claims. It follows that we cannot sustain any
of the Examiner's above § 103 rejections.
The decision of the Examiner is reversed.
REVERSED

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