Volkswagen AG

Patent Trials and Appeals Board

Apr 9, 2021

2020003053 (P.T.A.B. Apr. 9, 2021)

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.
15/302,567 10/07/2016 Philipp Mohr 1901.1020 1515
23280 7590 04/09/2021
Davidson, Davidson & Kappel, LLC
589 8th Avenue
22nd Floor
New York, NY 10018
EXAMINER
MCCONNELL, WYATT P
ART UNIT PAPER NUMBER
1727
NOTIFICATION DATE DELIVERY MODE
04/09/2021 ELECTRONIC
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.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
ddk@ddkpatent.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte PHILIPP MOHR and CHRISTIAN MARTIN ZILLICH
Appeal 2020-003053
Application 15/302,567
Technology Center 1700
Before N. WHITNEY WILSON, SHELDON M. MCGEE, and
JANE E. INGLESE, Administrative Patent Judges.
WILSON, Administrative Patent Judge.
DECISION ON APPEAL
Pursuant to 35 U.S.C. § 134(a), Appellant1 appeals from the
Examiner’s June 17, 2019 decision to finally reject claims 10–12 and 16–21
(“Final Act.”). We have jurisdiction under 35 U.S.C. § 6(b).
We reverse.
CLAIMED SUBJECT MATTER
Appellant’s disclosure is directed to a bipolar plate and to a fuel cell
(Abstract). According to the Specification, bipolar plates, which are also

1 We use the word Appellant to refer to “applicant” as defined in
37 C.F.R. § 1.42(a). Appellant identifies the real party in interest as Audi
Aktiengesellschaft (Appeal Br. 2).
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Application 15/302,567

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called flow field plates, are situated between the individual membrane–
electrode assemblies of a fuel cell2, and are used both for cooling and to
ensure a supply of the individual cells with the operating media, i.e., the
reactants (Spec. ¶ 2). Additionally, the bipolar plates are said to ensure an
electrically conductive contact with the membrane–electrode assemblies
(id.). The claimed bipolar plates have a specific structure, as set forth in the
claims. Claim 10, which is reproduced below from the Claims Appendix, is
illustrative of the claimed subject matter (emphasis added):
10. A bipolar plate comprising:
at least one profiled flow field including at least two flow
field channels including a first flow field channel and a second
flow field channel;
a first inlet channel and a first outlet channel associated
with the first flow field channel to define a first assembled
channel, and a second inlet channel and a second outlet channel
associated with the second flow field channel to define a second
assembled channel;
the first inlet channel having a different length than the
second inlet channel and the first outlet channel having a
different length than the second outlet channel;
the first and second inlet channels or the first and second
outlet channels are dimensioned in such a way that the pressure
loss of the first assembled channel and the second assembled
channel is equal if a same predetermined mass flow change takes
place in each of the first and second flow field channels;
the first and second assembled channels having an equal
length, the first inlet channel having a hydraulic diameter
differing from that of the second inlet channel or the first outlet
channel having a hydraulic diameter differing from that of the
second outlet channel; wherein the first flow field channel
connects solely to the first inlet channel at an inlet and solely to

2 A membrane-electrode assembly (MEA) “is a composite made of an ion–
conductive (usually proton–conductive) membrane and an electrode (anode
and cathode) situated on either side of the membrane” (Spec. ¶ 2).
Appeal 2020-003053
Application 15/302,567

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the first outlet channel at an outlet to define the first assembled
channel and wherein the second flow field channel connects
solely to the second inlet channel at a second inlet and solely to
the second outlet channel at a second outlet to define the second
assembled channel.
REFERENCE
The prior art relied upon by the Examiner is:
Name Reference Date
Goebel US 2007/0202383 A1 August 30, 2007

REJECTION
Claims 10–12 and 16–21 are rejected under 35 U.S.C. § 103 as
unpatentable over Goebel.
DISCUSSION
Appellant does not argue any claims individually (see, Appeal Br. 3–
6).3 Accordingly, we select claim 10 as representative. The remaining
claims will stand or fall with claim 10.
The Examiner’s findings are set forth at pages 2–4 of the Final
Action. The Examiner finds that Goebel discloses a bipolar plate which
addresses the problem of differing pressure drops in differing flow field
channels, leading to uneven reactant distribution (Final Act. 3). The
Examiner finds that Goebel teaches that this may be accomplished either by
adding additional flow channels, or by enlarging the cross-sectional

3 Appellant has not numbered the pages of the Appeal Brief. For purposes
of this opinion, we refer to the pages as though they were numbered. We
remind counsel for Appellant that it is helpful to the Board when the pages
of the briefs are numbered.
Appeal 2020-003053
Application 15/302,567

4
area/diameter of the single outlet channel (Final Act. 3–4, citing Goebel
¶ 51). Therefore, according to the Examiner, it would have been obvious to
modify Goebel’s system by changing the diameter of one or more of the
inlet, flow channel, or outlet of each assembled channel in order to tune its
pressure differential to ensure even reactant distribution, resulting in each
channel having a different diameter for either inlets, outlets, flow channels,
or all three. (Final Act. 3–4). According to the Examiner, such a
modification would result in a first flow channel that connects to only a first
inlet channel at the flow channel inlet and only a first outlet channel at a
flow channel outlet (id.).
Appellant argues that Goebel does not teach or suggest that its
system can be modified as suggested by the Examiner (Appeal Br. 4–
5). In particular, Appellant argues that the section of Goebel found by
the Examiner to suggest addressing pressure drops by enlarging the
cross-sectional area/diameter of the single outlet channel only
suggests such a method in addition to adding multiple flow channels
(id.). Thus, according to Appellant, a fair reading of Goebel does not
suggest the modifications needed to reach the claimed invention.
We are persuaded by Appellant’s argument. The passage cited
by the Examiner in support of the finding that Goebel reads as
follows:
[0051] It is understood that the size (hydraulic diameter or area)
of feed channels can be adjusted according to Equation 1 for
each of the embodiments described herein to achieve the
desired balance between feed channels. For example, in the
embodiment shown in FIG. 7, a group of flow channels 146,
148 may connect to the same integer number of intermediate
flow channels 150 as the flow channels are of different lengths.
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The size of longer flow channels 146, 148 of this group is
increased compared to the shorter flow channels 146, 148 of
this group. Also, as the flow channels 146, 148 connect to an
integer number of intermediate channels, some adjustment of
the flow channel 146, 148 sizes can be used to adjust to the
same pressure drop as other flow channels 146, 148.

(Goebel, ¶ 51, emphasis added).
The Examiner has the initial burden of establishing a prima
facie case of obviousness based on an inherent or explicit disclosure
of the claimed subject matter under 35 U.S.C. § 103. In re Oetiker,
977 F.2d 1443, 1445 (Fed. Cir. 1992) (“[T]he examiner bears the
initial burden, on review of the prior art or on any other ground, of
presenting a prima facie case of unpatentability.”). To establish a
prima facie case of obviousness, the Examiner must show that each
and every limitation of the claim is described or suggested by the prior
art or would have been obvious based on the knowledge of those of
ordinary skill in the art. In re Fine, 837 F.2d 1071, 1074 (Fed. Cir.
1988). The Examiner may not resort to hindsight reconstruction to
supply deficiencies in the prior art. In re Warner, 379 F.2d 1011,
1017 (CCPA 1967). Moreover, when determining obviousness, “the
prior art as a whole must be considered. The teachings are to be
viewed as they would have been viewed by one of ordinary skill.” In
re Hedges, 783 F.2d 1038, 1041 (Fed. Cir. 1986).
When considering the teachings of Goebel as a whole––as we
are required to do––we disagree with the Examiner that the teachings
of paragraph 51 extend to the prior art configurations depicted in
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Application 15/302,567

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Figures 2–4. These prior art configurations are not inventive
“embodiments” to which paragraph 51 fairly applies.
Thus, we agree with Appellant that paragraph 51 of Goebel would not
have fairly suggested to the skilled artisan to replace Goebel’s
multiple channels with a single channel, because this passage refers to
modifying the “embodiments” disclosed therein, each of which
contains multiple channels.
In sum, we determine that Goebel does not suggest a bipolar
plate “wherein the first flow field channel connects solely to the first
inlet channel at an inlet and solely to the first outlet channel at an
outlet to define the first assembled channel and wherein the second
flow field channel connects solely to the second inlet channel at a
second inlet and solely to the second outlet channel at a second outlet
to define the second assembled channel.”
Accordingly, we reverse the rejection.

DECISION SUMMARY
In summary:
Claim(s)
Rejected
35
U.S.C. §
Reference(s)/Basis Affirmed Reversed
10–12, 16–21 103 Goebel 10–12, 16–
21

REVERSED