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 .
Response to Amendment
The amendment filed 06/01/2026 has been entered.
Claims 1, 2, 5, 9 and 15 are amended; support for amended claim 1 can be found in Fig. 2c and paragraph [0018] of the specification.
The objections of Specification, and claims 2 and 15, made in the previous Office action are overcome by the amendment to the Drawings and Claims and withdrawn.
The 35 USC 112(b) rejection of claims 5 and 9 of the previous Office action, are overcome by the amendment and are withdrawn.
claims 1-15 are pending and are rejected under prior art on their merits below.
Response to Arguments
Applicant's arguments, see Remarks pages 8-9, filed 06/01/2026, with respect to independent claim 1, specifically the limitation of two independent flow path structural arrangement, have been fully considered and are persuasive in overcoming the 35 U.S.C. 102 rejection of the prior Office Action relying on Zare. However, the arguments are directed to limitations introduced by the amended claims that were not present in the claims at the time of the prior Office Action. Accordingly, a new ground of 35 U.S.C. 103 rejection relying on Zare in view of Xing (see citations above) is made in light of the claim amendments filed on 06/01/2026.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1-3, 5-12, and 14 are rejected under 35 U.S.C. 103 as being unpatentable over Zare et al. (US 20200020960 A1), and further in view of Xing et al. (CN 110854405 A, citations from enclosed machine translation).
Regarding claim 1, Zare teaches a bipolar plate (bipolar plate 405 in Fig 4A-4C) for a fuel cell stack (Abstract, Fig. 6, [0058]) the bipolar plate comprising: a first main boundary surface (first side of the bipolar plate, [0049]), a second main boundary surface (second side of the bipolar plate, [0049]), wherein the first and second main boundary surfaces are arranged parallel and at a distance to each other and define an interior space (Fig. 4A and Fig. 4B), wherein a plurality of lateral delimiting surfaces extend between outer edges of the first and second main boundary surfaces to enclose the interior space (Fig. 4A and Fig. 4B), wherein at least one of the lateral delimiting surfaces comprises a plurality of lateral openings (the top surface in Fig. 4A includes a plurality of openings; plurality of input holes 410), wherein the first main boundary surface, the second main boundary surface or both, comprise a plurality of axial openings (first side illustrated in Fig. 4A, and second side illustrated in Fig. 4B with plurality of openings), wherein a plurality of internal distribution channels are arranged inside the interior space at a distance to the first main boundary surface and the second main boundary surface ([0052]: a plurality of channels 440, Fig. 4B), and wherein the lateral openings of each of the at least one lateral delimiting surfaces are in fluid connection with the axial openings through at least a part of the internal distribution channels ([0055], claim 3).
Zare further teaches internal distribution channels arranged parallel to each other ([0021, 0033]); however, Zara is silent regarding the channels forming fluidically independent flow paths. Specifically, Zare does not teach a limitation wherein two fluidically independent fluid flow paths through the bipolar plate are created by the plurality of internal distribution channels, each fluidically independent fluid flow path extending from a lateral opening of the plurality of lateral openings in the at least one of the lateral delimiting surfaces to a corresponding group of axial openings of the plurality of axial openings in one of the first main boundary surface and the second main boundary surface.
However, Xing teaches parallel flow channels supplied through two separate inlets 3, and 4 (Fig. 1; page 2, lines 33-35; page. 9, lines 36-51). Xing further teaches that the two inlets supply the same fluid -air- to respective fluid channels of the bipolar plate. In particular, inlet 3 supplies air to the inner flow channel, and inlet 4 supplies aria to the outer flow channel; the terms “inner” and “outer” identify the location of the respective flow channels (page. 3, lines 41-48; page. 9, lines 36-51). Therefore, the respective flow channels provide separate flow paths for the same fluid.
Xing further teaches independently supplying the same fluid through inlets 3, and 4 at different inlet pressure to establish a pressure difference between the respective flow channels to improve the diffusivity of reaction gas and thereby improving the fuel cell performance (page. 2, lines 15-23, and 27-29; page 3, lines 38-48, and 50-56).
Further, Zare, and Xing are considered to be analogous to the claimed invention because both references are directed to flow channel arrangement in bipolar plates.
Therefore, it would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to modify the parallel internal distribution channels of Zare according to the teaching of Xing such that the same fluid is supplied through two fluidically independent flow paths thereby creating pressure different between the flow paths to improve the diffusivity of reaction gas and thereby improving the fuel cell performance (page. 2, lines 15-23, and 27-29; page 3, lines 38-48, and 50-56). It would have been a matter of design choice for one of ordinary skill in the art to incorporate the fluidically independent flow paths as taught by Xing into the internal distribution channels and corresponding openings on the applicable surfaces of Zare’s bipolar plate, thereby obtaining the claimed arrangement.
Regarding claim 2, Zare, as modified by Xing, teaches all claim limitations of claim 1 as stated above. Zare further teaches a limitation wherein a first lateral delimiting surface comprises a plurality of first lateral openings (the top surface in Fig. 4A includes a plurality of openings; plurality of input holes 410), wherein a second lateral delimiting surface comprises a plurality of second lateral openings ([0025]: plurality of holes 110 may extend from the first side to a second side of the bipolar plate 116 wherein second side is different than the first side) , wherein the first main boundary surface comprises a plurality of first axial openings (Fig. 4A), wherein the second main boundary surface comprises a plurality of second axial openings (Fig. 4B), wherein first internal distribution channels and second internal distribution channels are arranged inside the interior space (First and second channels, [0055], [0056], Fig. 5)), wherein the first lateral openings are connected to the first axial openings through the first internal distribution channels ([0033]: the second channel may conduct the portion of the reactants 102 and/or the reaction products to the one or more output holes 112), and wherein the second lateral openings are connected to the second axial openings through the second internal distribution channels ([0055]: the channel 515 may extend from a first part of the second side of the bipolar plate 505 to a third side of the bipolar plate 505).
Regarding claim 3, Zare, as modified by Xing, teaches all claim limitations of claim 2 as stated above. Zare further teaches a limitation wherein the first lateral delimiting surface and the second lateral delimiting surface follow on each other in a circumferential direction and are arranged at an angle of 60° to 120° to each other ([0056]: an angle between the first direction and the second direction may be greater than 90 degrees and/or less than 90 degrees.).
Regarding claim 5, Zare, as modified by Xing, teaches all claim limitations of claim 1 as stated above. Zare further teaches a limitation wherein the plurality of internal distribution channels are arranged parallel to each other ([0021, 0033]).
Regarding claim 6, Zare, as modified by Xing, teaches all claim limitations of claim 1 as stated above. Zare further teaches a limitation wherein the internal distribution channels are straight (Fig. 5, plurality of channels 510), and wherein each associated axial opening is in fluid connection with a respective internal distribution channel through a branch merging into the respective internal distribution channel (Fig. 5, 525).
Regarding claim 7, Zare, as modified by Xing, teaches all claim limitations of claim 6 as stated above. Zare further teaches a limitation wherein the branch has a curved shape that transitions between an intended flow direction of the respective internal distribution channel and an outflow axis of the respective axial opening (curved shape branch in Fig. 5).
Regarding claim 8, Zare, as modified by Xing, teaches all claim limitations of claim 1 as stated above. Zare further teaches a limitation wherein each lateral opening is associated with one internal distribution channel (Fig. 4B, Fig. 4C, Fig 5, [0052], [0055]: the plurality of channels 510 may be located across openings of the plurality of holes).
Regarding claim 9, Zare, as modified by Xing, teaches all claim limitations of claim 1 as stated above. Zare further teaches a limitation wherein the lateral openings of the respective lateral delimiting surface are arranged in a plurality of parallel lateral rows (Fig. 4A). Zare discloses a plurality of input holes 410 arranged on a lateral surface in a single row. Mere duplication of parts, providing multiple rows instead of a single row as shown in Zare, does not result in a patentably distinct structure and would have been obvious to one of ordinary skill in the art. See In re Harza, 124 USPQ 378 (CCPA 1960); see also MPEP § 2144.04.
Regarding claim 10, Zare, as modified by Xing, teaches all claim limitations of claim 1 as stated above. Zare further teaches a limitation wherein the axial openings of a respective main boundary surface are arranged in a matrix having a plurality of axial columns and a plurality of axial rows (enlarged view 430 of the plurality of holes 415 in Fig. 4A).
Regarding claim 11, Zare, as modified by Xing, teaches all claim limitations of claim 10 as stated above. Zare further teaches a limitation wherein a number of axial openings in a respective axial row or axial column corresponds to a number of lateral openings in a lateral row (based on [0026], flexible number of axial openings is interpreted). Zare teaches multiple axial openings and multiple lateral openings (elements 410 and 415 in Fig. 4A); the specific numerical correspondence between the axial openings and the lateral openings represents a matter of design choice. Mere duplication or reduction of parts, i.e., increasing or decreasing the number of lateral openings and/or axial openings relative to those shown in Zare, does not result in a patentably distinct structure and would have been obvious to one of ordinary skill in the art. See In re Harza, 124 USPQ 378 (CCPA 1960); see also MPEP § 2144.04.
Regarding claim 12, Zare, as modified by Xing, teaches all claim limitations of claim 1 as stated above. Zare further teaches a limitation wherein a diameter of the internal distribution channels exceeds a diameter of the lateral openings or of the axial openings, or of both ([0025], [0028], and [0032] teach different diameter for holes).
Regarding claim 14, Zare, as modified by Xing, teaches all claim limitations of claim 1 as stated above. Zare further teaches a limitation wherein a fuel cell stack comprises the bipolar plate ([0058], Fig. 6).
Claim 4 is rejected under 35 U.S.C. 103 as being unpatentable over Zare, as modified by Xing, as applied to claim 2 above, and further in view of Kim et al. (KR 100664077 B1, citations from enclosed machine translation).
Regarding claim 4, Zare, as modified by Xing, teaches all claim limitations of claim 2 as stated above. Zare further teaches a limitation wherein the first lateral openings and the first internal distribution channels are arranged further to the first main boundary surface than to the second main boundary surface (interpreted from Fig. 5).
Modified Zare fails to teach a limitation wherein the second lateral openings and the second internal distribution channels are arranged further to the second main boundary surface than to the first main boundary surface, and wherein the first internal distribution channels and the second internal distribution channels are arranged at a distance to each other.
However, Kim teaches the missing limitation. Specifically, Kim discloses that the first internal distribution channels and the second internal distribution channels of a bipolar plate (Fig. 5, Fig. 6, and Fig. 7; channels 56 and 57 of bipolar plate 51) are arranged at a distance to each other (interpreted from Fig. 5 and Fig. 6; paragraph 5 of TECH-SOLUTION). Further, modified Zare, and Kim are considered to be analogous to the claimed invention because both are in the same field of bipolar plate.
Therefore, it would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to incorporate the channel spacing structure taught by Kim into the bipolar plate of modified Zare, such that the second internal distribution channels have the same structural arrangement as the first internal distribution channels of modified Zare, with corresponding second lateral openings. In doing so, the second lateral openings and the second internal distribution channels would be arranged further to the second main boundary surface than to the first main boundary surface, while the first lateral openings and the first internal distribution channels are arranged further to the first main boundary surface than to the second main boundary surface, as claimed. This arrangement would have been obvious because it reduces the fluid travel distance between the lateral openings and the internal distribution channels. By positioning one set of channels closer to anode-side surface and other set closer to the cathode side surface, reactant gases can be delivered more directly to their respective electrodes. Accordingly, a person of ordinary skill in the art would have been motivated to adapt this channel arrangement to achieve improved fluid management .
Claim 13 is rejected under 35 U.S.C. 103 as being unpatentable over Zare, as modified by Xing, as applied to claim 1 above, and further in view of Wilson et al. (US 11424460 B1).
Regarding claim 13, Zare as modified by Xing, teaches all claim limitations of claim 1 as stated above. Modified Zare fails to teach a limitation wherein the bipolar plate is made by a 3D printing process.
However, Wilson teaches the limitation wherein the bipolar plate (porous sub-plate 104 of the bipolar plate 100) is made by a 3D printing process ([0038]). Wilson also teaches that by using 3D printing, features such as the channels are formed ([0038]). Further, modified Zare, and Wilson are considered to be analogous to the claimed invention because both are in the same field of bipolar plate.
Therefore, it would have been obvious before the effective filing date of the claimed invention that one of ordinary skill in the art would use said 3D printing as taught by Wilson to said bipolar plate as taught by modified Zare to form features such as channels in a surface of bipolar plate.
Claim 15 is rejected under 35 U.S.C. 103 as being unpatentable over Zare , as modified by Xing, as applied to claim 14 above, and further in view of Wolff et al. (US 20200313203 A1).
Regarding claim 15, Zare as modified by Xing, teaches all limitations of claim 14 as stated above. Modified Zare fails to teach a limitation wherein an aircraft comprises a fuel cell system having the fuel cell stack of claim 14.
However, Wolff teaches the limitation wherein an aircraft comprises a fuel cell system having the fuel cell stack (claim 15). Wolff further teaches that a compact fuel cell system with a bipolar plate that is simple to cool is incorporated in an aircraft ([0042]). Further, modified Zare, and Wolff are considered to be analogous to the claimed invention because both are in the same field of bipolar plate.
Therefore, it would have been obvious before the effective filing date of the claimed invention that one of ordinary skill in the art would incorporate the fuel cell system as taught by modified Zare into the aircraft as taught by Wolff in order to obtain a compact fuel cell system that is simple to cool.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Lili Rassouli whose telephone number is (571)272-9760. The examiner can normally be reached Monday-Thursday 8:00 AM-4:00 PM.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Matthew T Martin can be reached at (571) 270-7871. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/LILI RASSOULI/ Examiner, Art Unit 1728
/MATTHEW T MARTIN/Supervisory Patent Examiner, Art Unit 1728
Prosecution Insights