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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on August 25, 2026 has been entered.
Response to Amendment
In response to the amendment filed July 29, 2026, entered as per the RCE filed August 25, 2026:
Claims 1-2, 6-9, 13-16 and 19-20 are pending. Claims 3-5, 10-12 and 17-18 have been canceled as per Applicant’s request;
The 102 rejection to Kaiser et al. set forth in the previous Office Action is withdrawn in light of the amendment.
The 103 rejections to Kaiser et al. in view of Kadowaki et al. set forth in the previous Office Action stand in light of the amendment.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claims 1, 6-8, 13-15 and 19-20 are rejected under 35 U.S.C. 103 as being unpatentable over Kaiser et al. (EP 1511102A2) in view of Kadowaki et al. (JP 2000-251907A).
As to claim 1, Kaiser discloses an apparatus (bipolar plate) comprising:
a plurality of flow field channels, wherein the plurality of flow field channels includes:
a plurality of ribs (walls between each flow path in the array of channels shown in Fig. 6 below) connecting an inlet and an outlet in a serpentine flow design; and
a plurality of blocking ribs within the plurality of ribs (see annotated Fig. 6 below).
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As shown above Kaiser shows a first larger serpentine flow field wherein, the additional blocking ribs in the triangular area above are further representative of a further serpentine pathway within that area, as part of the larger serpentine flow field. Additional annotated copies of Fig. 6 are provided below.
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Thus at least a portion of the flow field of Kaiser is a serpentine-in-serpentine design.
As to claim 6, gases flow in a serpentine pattern between the blocking ribs within the serpentine pattern of the plurality of ribs defining flow channels (Fig. 6 for example).
As to claim 7, the plurality of ribs are congruent (Fig. 6 for example).
As to claim 8, Kaiser discloses a fuel cell (see pages 1-2 of the machine translation and the claims on page 14 of the machine translation) comprising:
a plurality of flow field channels, wherein the plurality of flow field channels includes:
a plurality of ribs (walls between each flow path in the array of channels shown in Fig. 6 below) connecting an inlet and an outlet in a serpentine flow design; and
a plurality of blocking ribs within the plurality of ribs (see annotated Fig. 6 below).
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As shown above Kaiser shows a first larger serpentine flow field wherein, the additional blocking ribs in the triangular area above are further representative of a further serpentine pathway within that area, as part of the larger serpentine flow field. Additional annotated copies of Fig. 6 are provided below.
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Thus at least a portion of the flow field of Kaiser is a serpentine-in-serpentine design.
As to claim 13, gases flow in a serpentine pattern between the blocking ribs within the serpentine pattern of the plurality of ribs defining flow channels (Fig. 6 for example).
As to claim 14, the plurality of ribs are congruent (Fig. 6 for example).
As to claim 15, Kaiser discloses a method comprising:
creating a fuel cell (see pages 1-2 of the machine translation and the claims on page 14 of the machine translation) with a plurality of flow field channels, wherein the plurality of flow field channels includes:
a plurality of ribs (walls between each flow path in the array of channels shown in Fig. 6 below) connecting an inlet and an outlet in a serpentine flow design; and
a plurality of blocking ribs within the plurality of ribs (see annotated Fig. 6 below).
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As shown above Kaiser shows a first larger serpentine flow field wherein, the additional blocking ribs in the triangular area above are further representative of a further serpentine pathway within that area, as part of the larger serpentine flow field. Additional annotated copies of Fig. 6 are provided below.
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Thus at least a portion of the flow field of Kaiser is a serpentine-in-serpentine design.
As to claim 19, gases flow in a serpentine pattern between the blocking ribs within the serpentine pattern of the plurality of ribs defining flow channels (Fig. 6 for example).
As to claim 20, the plurality of ribs are congruent (Fig. 6 for example).
Kaiser teaches of providing an array of blocking ribs along the walls (ribs) of at least a portion of the flow channels of a serpentine flow field channel array as discussed above. The design provides for flow which includes a serpentine flow path between the blocking ribs along a larger serpentine flow path of the flow channel itself (as discussed above).
Kaiser does not teach of the blocking ribs including first and second sets of blocking ribs attached to different portions of the ribs (claims 1, 8 and 15). Kaiser teaches of flow field designs wherein members provided in the serpentine flow field channel can improve flow efficiency therein.
Kadowaki is drawn to the same field of endeavor relating to fuel cell flow fields and improving fluid flow in the channels of the flow field plate. Kadowaki discloses that various flow field designs can be implanted including providing blocking ribs attached to the channel ribs themselves (Fig. 2) with alternating blocking ribs therein attached to both the upper and lower portions of the ribs. Kadowaki teaches that placement of blocking ribs in various ways can improve fluid flow within the flow channel.
In re Kuhle, 526 F.2d 553, 188 USPQ 7 (CCPA 1975) (the particular placement of a contact in a conductivity measuring device was held to be an obvious matter of design choice).
As discussed above there has been prior legal precedent showing that rearrangement of a part in the face of a prior art teaching, a reasonable statement of such modification to be of routine design choice to provide the same desired benefit of either configuration.
In similar fashion, the difference between Kaiser and the claims noted above appears to be attachment of the blocking ribs to different portions of the ribs/walls. Providing the blocking ribs of Kaiser to upper and lower portions of the ribs of the flow channels themselves (as taught by Kadowaki) can similarly improve fluid flow within the flow channel. Rearranging the placement/location of blocking ribs within a flow channel as taught by Kadowaki to the flow channel of Kaiser (which appreciated the inclusion of blocking ribs in the flow channel) is held to have been a matter of routine design choice for modifying fluid flow within the flow channel absent some unexpected advantage to the particular attachment of blocking ribs to the ribs rather than the plate.
Therefore it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the flow field design of Kaiser to include blocking ribs provided at the ribs at upper and lower portions of the ribs as taught by Kadowaki since it would have provided a suitable attachment design to effectively improve fluid flow along the flow field channels where blocking ribs are disposed on the flow channel walls/ribs themselves (Kaiser). Furthermore, rearranging the placement of the ribs to certain portions of the walls/ribs in the flow field channel including the ribs defining the flow channel (Kadowaki) would have been of routine design choice for modifying fluid flow within the flow channel absent some unexpected advantage to the particular attachment of blocking ribs to the ribs rather than the plate. In re Kuhle, 526 F.2d 553, 188 USPQ 7 (CCPA 1975).
Claims 2, 9 and 16 are rejected under 35 U.S.C. 103 as being unpatentable over Kaiser et al. (EP 1511102A2) in view of Kadowaki et al. (JP 2000-251907A) as applied to claims 1, 8 and 15 above, and further in view of Kim et al. (U.S. Patent Application Publication No. 2019/0229348).
Kaiser teaches of providing an array of blocking ribs along the walls (ribs) of at least a portion of the flow channels of a serpentine flow field channel array as discussed above. The design provides for flow which includes a serpentine flow path between the blocking ribs along a larger serpentine flow path of the flow channel itself (as discussed above).
Kaiser does not appear to explicitly teach of at least a portion of the blocking ribs within the plurality of blocking ribs attached to a plate (claims 2, 9 and 16).
Providing the blocking ribs to the base plate either directly or indirectly would have provided for a design that effectively permitted the serpentine in serpentine flow of fluid through the flow field of Kaiser. The design would have further provided a mechanical integration while providing the necessary functionality of the blocking ribs in that region. Making the blocking ribs integral with the plate supports the structure while also defining the gas flow paths.
Kim is drawn to the same field of endeavor relating to fuel cell flow fields and improving fluid flow in the channels of the flow field plate. Kim discloses an apparatus (fuel cell separator) comprising a plurality of flow field channels 100 (110/120), wherein the plurality of flow field channels includes a plurality of ribs (defining the flow field channels 100) connecting an inlet and an outlet in a serpentine flow design; and a plurality of blocking ribs 141, 142 within the plurality of ribs (Figs. 2 below and further Figs. 4-7, 9-12b, and 14).
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The blocking ribs 141 and 142 are attached to a base plate surface (Fis. 4-5 and corresponding disclosure).
Even though the location of the ribs are different in placement, the concept recognized that the ribs are attached to the overall structure of the flow field plate and are not free-floating. It would be reasonably obvious to have the walls/ribs of Kaiser to be attached to the base plate of the flow field (either directly or indirectly) to effectively provide for the flow field design implemented by Kaiser where the blocking ribs are disposed along the entire height of the flow field (thus from the base plate of the flow field to the top of the ribs of the flow field) to provide the effective flow effect necessitated within the blocking rib region and overall flow field design of Kaiser.
Kadowaki is drawn to the same field of endeavor relating to fuel cell flow fields and improving fluid flow in the channels of the flow field plate. Kadowaki discloses that various flow field designs can be implanted including providing blocking ribs attached to the channel ribs themselves that are attached to the side walls and base plate (Fig. 2).
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Kadowaki teaches that placement of blocking ribs in various ways can improve fluid flow within the flow channel but also recognized that the blocking ribs along a longer flow field path traverses the entire height of the flow field and is attached to the base plate of the flow field. The design would have further provided a mechanical integration while providing the necessary functionality of the blocking ribs in that region for manipulation of fluid flow along the flow field channel or path. Making the blocking ribs integral with the plate mechanically supports the structure while also defining the gas flow paths and requisite functionality.
Therefore it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to couple the blocking ribs of Kaiser to the base plate of the flow field as taught by Kim or Kadowaki since it would have provided a design which provided both mechanical and functional integration of the blocking ribs of Kaiser in the flow field design of Kaiser. Such modified blocking ribs would have effectively traversed the entire height of the flow field, thereby effectively influencing the flow through the blocking ribs along the entire height of a larger flow field channel and would have provided both the aforementioned functionality while providing additional effective mechanical integration of the blocking ribs into the flow field plate by coupling them to the base plate of the flow field.
Response to Arguments
Applicant's arguments filed July 29, 2026 have been fully considered but they are not persuasive.
Applicant’s argument that neither Kaiser nor Kadowaki teach of blocking ribs defining a continuous serpentine flow path between adjacent ribs with the serpentine flow design of the plurality of ribs.
As discussed above, Kaiser does show a greater serpentine flow field, defined by walls or extending ribs which are further modified in a triangular region with additional ribs (blocking ribs) to effectively form a larger serpentine flow field coupled with an additional serpentine flow path within the larger serpentine flow field along the triangular region.
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Therefore, as shown above, an array of “blocking” ribs are provided in the triangular region of Kaiser and these ribs are attached to corresponding longer ribs defining the greater serpentine flow path from inlet to outlet.
As further discussed above, Kaiser teaches that along the greater serpentine flow path, at least a section of the serpentine flow path includes blocking ribs defining a continuous serpentine flow path between adjacent ribs at a given section of the greater serpentine flow path. Thus Kaiser teaches of a serpentine flow path having a further continuous serpentine flow path along the region where the blocking ribs reside.
The claims are still broadly written to encompass a serpentine in serpentine design wherein blocking ribs, defining a second serpentine flow path reside in the first flow path of the plurality of ribs to any extent. It may be that Applicant is interpreting the blocking ribs to reside in a manner different than Kaiser (as may be noted from the disclosure and figures) but as the claims currently stand, the blocking ribs can reside only in a portion of the flow field and still read on this feature.
Again, regarding the first and second set of blocking ribs along a longer flow path defined by plural ribs, Kadowaki recognized such a design. Kadowaki discloses that various flow field designs can be implanted including providing blocking ribs attached to the channel ribs themselves (Fig. 2) with alternating blocking ribs therein attached to both the upper and lower portions of the ribs. Kadowaki teaches that placement of blocking ribs in various ways can improve fluid flow within the flow channel.
In the art of flow field designs, it has long since been known to vary the flow field paths in a variety of ways to improve reactant flow and distribution along the flow field. Modifying the design to improve these parameters and improve electrochemical performance would have been of routine skill in the art. In re Kuhle, 526 F.2d 553, 188 USPQ 7 (CCPA 1975) (the particular placement of a contact in a conductivity measuring device was held to be an obvious matter of design choice).
Again, as discussed above there has been prior legal precedent showing that rearrangement of a part in the face of a prior art teaching, a reasonable statement of such modification to be of routine design choice to provide the same desired benefit of either configuration. In similar fashion, the difference between Kaiser and the claims noted above appears to be attachment of the blocking ribs to different portions of the ribs/walls. Tuning the design and arrangement of the blocking ribs of Kaiser to upper and lower portions of the ribs of the flow channels themselves (as taught by Kadowaki) can similarly and expectedly improve fluid flow within the flow channel. Rearranging the placement/location of blocking ribs within a flow channel as taught by Kadowaki to the flow channel of Kaiser (which appreciated the inclusion of blocking ribs in the flow channel) is held to have been a matter of routine design choice for tuning fluid flow within the flow channel absent some unexpected advantage to the particular attachment of blocking ribs to the ribs rather than the plate.
Therefore, as noted above, the Examiner maintains that it would have been obvious to a person of ordinary skill in the art before the effective filing date of the claimed invention to modify the flow field design of Kaiser to include blocking ribs provided at the ribs at upper and lower portions of the ribs as taught by Kadowaki since it would have predictably provided a suitable attachment design to effectively improve fluid flow along the flow field channels where blocking ribs are disposed on the flow channel walls/ribs themselves (Kaiser). Furthermore, rearranging the placement of the ribs to certain portions of the walls/ribs in the flow field channel including the ribs defining the flow channel (Kadowaki) would have been of routine design choice for modifying fluid flow within the flow channel absent some unexpected advantage to the particular attachment of blocking ribs to the ribs rather than the plate.
Applicant argues that Kadowaki does not teach the blocking ribs defining a serpentine flow path within another serpentine flow path defined by the plurality of ribs. This argument is held to be a piecemeal analysis as Kaiser is relied upon to show the core concept of a serpentine-in-serpentine flow path wherein blocking ribs reside within the greater flow path to define an additional serpentine flow path along the greater serpentine flow path. In response to applicant's arguments against the references individually, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986).
As to Applicant’s arguments to In re Japiske, the Examiner has reconsidered the applicability of this decision and finds Applicant’s arguments persuasive.
Applicant’s remarks to In re Kuhle, Applicant merely states that the location of the blocking ribs is not merely aesthetic or an interchangeable design selection.
This argument is not persuasive as it does not provide clear evidence that the specific feature solves a specific problem and/or produces unexpected results. Applicant’s remarks fail to provide clear and convincing evidence to clearly establish that the placement is not arbitrary, aesthetic and interchangeable. The argument to aesthetics is further not convincing as a person of ordinary skill in the art would have readily understood that flow field designs are not aesthetic but are functional. Therefore the argument to aesthetics is not persuasive and not relevant. The argument to not interchangeable is also not persuasive as there is no evidence or technical reasoning presented by Applicant to explain what differs when exchanged.
In essence, Applicant’s arguments to In re Kuhne lack sufficient factual and technical evidence to support Applicant’s allegation that In re Kuhne is misplaced.
Kaiser teaches that a blocking rib design within a plurality of ribs where both the plurality of ribs and blocking ribs provided for serpentine flow paths is known for improving the flow field design. Kadowaki teaches attaching or positioning blocking ribs on plurality ribs at different parts of the plurality of ribs to modify the flow within the channel. In view of the known objective of improving reactant flow, selecting the claimed attachment position would have been an obvious and predictable implementation based on Kaiser in view of Kadowaki for at least those reasons discussed above, absent clear evidence to the contrary. Therefore, the prior art rejections stand.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to GREGG CANTELMO whose telephone number is (571)272-1283. The examiner can normally be reached Mon-Thurs 7am to 5pm.
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/GREGG CANTELMO/Primary Examiner, Art Unit 1725
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