iDETAILED 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 .
Priority
Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
Information Disclosure Statement
The information disclosure statement (IDS) submitted on 02/08/2024 and 03/22/2024 are in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement is being considered by the examiner.
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.
Claims 1, 2, 5, 7, 9-12, and 14-15 are rejected under 35 U.S.C. 103 as being unpatentable over Kongkanand et al. (US 20100081025 A1), and further in view of Kato et al. (JP 2020047443 A, as cited in the IDS filed 02/08/2024, citations from enclosed machine translation).
Regarding claim 1, Kongkanand teaches a distributor plate (7) for an electrochemical cell (1) ([0030], Fig. 1, electrically conductive fluid distribution element 8, hereinafter bipolar plate 8, of fuel cell stack 2), wherein the distributor plate (7) has a structure, comprising bridges (12), each having a top surface (13) ([0030], Fig. 2, lands 25 having top surface), and main channels (11) each having a base surface (33) ([0030], Fig. 2, flow channels 17 having base surface), wherein the top surface (13) has a coating (37), and the coating (37) is at least partially porous ([0040], Fig. 5, hydrophilic surface 92 formed by applying a hydrophilic coating).
Specifically, Kongkanand teaches that the flow fields 18 and 20 include a plurality of flow channels 17 and a plurality of lands 25 ([0030], Fig. 2), wherein the lands correspond to the claimed bridges and the flow channels correspond to the claimed main channels.
Kongkanand further teaches two alternative surface treatments for improving hydrophilicity, namely applying a hydrophilic coating and forming a plurality of pores ([0040]). It would have been obvious to one of ordinary skill in the art to combine these known hydrophilicity-enhancing techniques by providing pores in the hydrophilic coating itself, thereby yielding at least partially porous hydrophilic coating and predictably improving hydrophilic properties ([0040]).
Kongkanand doesn’t teach a limitation wherein the top surface (13) has at least one secondary channel (15) and a coating that covers at least parts of the at least one secondary channel (15).
However, Kato teaches this limitation. Specifically, Kato teaches a separator ([0010], separator 40) corresponding to the claimed distributor plate, wherein the separator includes ribs 431 and 432 ([0017]) corresponding to the claimed bridges and flow grooves 411, 412, and 413 ([0017]) corresponding to the claimed main channels.
Kato further teaches fine grooves 431a and 432a formed on the top surfaces of ribs 431 and 432 corresponding to the claimed secondary channel (15) ([0021], Figs. 3-5).
Kato further teaches that liquid water is captured in the fine grooves and that stagnation of liquid water in the fine grooves is suppressed, thereby improving drainage ([0024]).
Further, Kongkanand and Kato are considered to be analogous to the claimed invention because both references are directed to fuel-cell separator/bipolar plate structures and, to improving water management and drainage in fuel-cell flow fields.
Therefore, it would have been obvious before the effective filing date of the claimed invention to one of ordinary skill in the art to modify the bipolar plate of Kongkanand by providing fine grooves 431a and 432a on the top surfaces of lands 25 as taught by Kato in order to improve liquid-water capture and drainage ([0024]). The modification would have resulted in a structure in which the hydrophilic coating of Kongkanand covers at least portions of the added fine grooves because the coating is applied to the flow-field surface and would coat at least portions of the fine grooves formed therein. the arrangement of the coating relative to the recessed grooves merely represents the predictable result of applying a known coating to a known grooved surface. Such positioning represents a mere rearrangement of known parts yielding predictable results and is therefore considered obvious to one of ordinary skill in the art. See MPEP 2144.04(VI)(C).
Regarding claim 2, Kongkanand, as modified by Kato, teaches all limitations of claim 1 as stated above. Modified Kongkanand further teaches a limitation wherein the at least one secondary channel (15) forms a cavity (158) between the coating (37) and the top surface (13) (Kato [0021], Fig. 3, fine grooves 431a and 432a, and the porous coating of Kongkanand).
Specifically, Kato teaches recessed fine grooves 431a and 432a formed on the surfaces of ribs 431 and 432 ([0021], Fig. 3). As discussed above with respect to claim 1, it would have been obvious to provide the fine grooves/second channels of Kato on the top surfaces of the lands/bridges of Kongkanand in order to improve liquid-water capture and drainage, because Kato teaches that liquid water is captured in the fine grooves and stagnation of liquid water in the grooves is suppressed, thereby improving drainage (Kato [0024]).
The modification would have resulted in a structure in which the hydrophilic coating of Kongkanand covers at least portions of the added fine grooves because the coating is applied to the flow-field surface and would coat at least portions of the fine grooves formed therein. Because the fine grooves remain recessed below the top surface while being at least partially covered by the coating, the recessed grooves define cavities between the coating and the underlying top surface.
Further, the arrangement of the coating relative to the recessed grooves merely represents the predictable result of applying a known coating to a known grooved surface. Such positioning represents a mere rearrangement of known parts yielding predictable results and is therefore considered obvious to one of ordinary skill in the art. See MPEP 2144.04(VI)(C).
Therefore, it would have been obvious before the effective filing date of the claimed invention to modify the modified bipolar plate of Kongkanand by providing the fine grooves of Kato on the bridge surfaces, the recessed grooves at least partially covered by the coating, form a cavity between the coating and the top surface, in order to improve liquid-water capture and drainage as taught by Kato ([0024]).
Regarding claim 5, Kongkanand, as modified by Kato, teaches all limitations of claim 1 as stated above. Kato further teaches a limitation wherein the at least one secondary channel (15) extends to a lateral top surface (31) of the bridges (12) ([0023-0026]).
Specifically, Kato teaches fine grooves 431a and 432a formed on the surfaces of ribs 431 and 432 ([0021], Fig. 3). Kato further teaches that the end of the fine groove 431a on the groove 411 side is connected to the drain groove 411b, and the end of the fine groove 431a on the groove 412 side extends to the drain groove 412b. Likewise, the ends of fine groove 432a are connected to drain grooves 412c and 413b ([0023]). Accordingly, Kato teaches secondary grooves extending from the upper rib surfaces to side drain grooves located at the lateral sides of the ribs.
Kato further teaches that, by providing these connections, stagnation of liquid water in the fine grooves is suppressed and drainage is improved ([0024-0026]).
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 distributor plate of modified Kongkanand by extending the secondary channels formed on the bridge surfaces to the lateral top surfaces of the bridges, as taught by Kato, in order to improve liquid-water removal and drainage within the flow field ([0024-0026]).
Regarding claim 7, Kongkanand, as modified by Kato, teaches all limitations of claim 1 as stated above. Kato further teaches a limitation wherein the top surface (13) comprises at least two secondary channels (15) and the at least two secondary channels (15) are arranged at different angles (19) to the main channels (11) ([0024, 0035]).
Specifically, Kato teaches, in Fig. 3, fine grooves 431a and 432a that extend between the main grooves 411, 412, and 413 and are arranged at an angle relative thereto. Kato also teaches that the fine grooves may have a shape of merging from four to two, or may have a shape of merging from a plurality of grooves to a smaller number of grooves ([0035]). Kato further teaches that stagnation of liquid water in the fine grooves 431a and 432a is suppressed and drainage is improved ([0024]).
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 distributor plate of modified Kongkanand to include at least two secondary channels arranged at an angle relative to the main channels, as taught by Kato, in order to improve drainage and suppress stagnation of liquid water ([0024]).
Regarding claim 9, Kongkanand, as modified by Kato, teaches all limitations of claim 7 as stated above. Kato further teaches a limitation wherein the at least two secondary channels (15) are connected to each other by a further secondary channel (15) ([0024, 0033, 0035]).
Specifically, Kato teaches fine groove 431b comprising branch portions 4311, 4312, and 4313 that merge at a single merge portion (junction) 4315 ([0033], Fig. 5A). Thus, Kato teaches at least two secondary channels that are connected to each other by a further secondary channel. Kato further teaches that the fine grooves may have a shape of merging from a plurality of grooves to a smaller number of grooves ([0035]). Kato additionally teaches that stagnation of liquid water in the fine grooves 431a and 432a is suppressed and drainage is improved ([0024]).
Therefore, it would have been obvious before the effective filing date of the claimed invention to modify the distributor plate of modified Kongkanand to include at least two secondary channels connected to each other by a further secondary channel, as taught by Kato, in order to improve drainage and suppress stagnation of liquid water ([0024]).
Regarding claim 10, Kongkanand, as modified by Kato, teaches all limitations of claim 1 as stated above. Kongkanand further teaches an electrochemical cell (1) comprising a distributor plate (7) according to claim 1 ([0030, 0032], Figs. 1, 2; the fuel cell stack 2 constitutes an electrochemical cell).
Regarding claim 11, Kongkanand, as modified by Kato, teaches all limitations of claim 1 as stated above. Kongkanand further teaches a limitation wherein the coating (37) is water-permeable ([0040, 0042]).
Specifically, Kongkanand teaches forming a plurality of pores in the hydrophilic coating and teaches that the hydrophilic flow field is adapted to wick water away by capillary action and facilitate increased water removal ([0040, 0042]). A porous hydrophilic coating that wicks water away by capillary action necessarily permits water transport through the coating and is therefore water-permeable.
Regarding claim 12, Kongkanand, as modified by Kato, teaches all limitations of claim 11 as stated above. Kongkanand further teaches a limitation wherein the coating (37) is hydrophilic ([0040]; hydrophilic surface 92).
Specifically, Kongkanand teaches that the hydrophilic surface 92 can be produced by applying a hydrophilic coating ([0040]).
Regarding claim 14, Kongkanand, as modified by Kato, teaches all limitations of claim 1 as stated above. Kato further teaches a limitation wherein the at least one secondary channel (15) includes a change of direction (156) ([0024, 0034-0035]).
Specifically, Kato teaches a plurality of fine grooves in Fig. 5B, including fine grooves 4311, 4312, and 4313, that merge into a smaller number of grooves, such as grooves 4316 and 4317 ([0034-0035]). The merging configuration necessarily results in at least one groove changing direction. Kato further teaches that stagnation of liquid water in the fine grooves is suppressed and drainage is improved ([0024]).
Therefore, it would have been obvious before the effective filing date of the claimed invention that one of ordinary skill in the art would modify the distributor plate of modified Kongkanand to include at least one secondary channel including a change of direction, as taught by Kato, in order to improve drainage ([0024]).
Regarding claim 15, Kongkanand, as modified by Kato, teaches all limitations of claim 7 as stated above. Kato further teaches a limitation wherein the at least two secondary channels (15) intersect (Fig. 5B, [0024, 0034-0035]).
Specifically, Kato teaches a plurality of fine grooves 4311, 4312, and 4313 that merge into a smaller number of grooves, such as grooves 4316 and 4317 ([0034-0035], Fig. 5B). The merging configuration results in at least two secondary channels intersecting or joining one another. Kato further teaches that stagnation of liquid water in the fine grooves 431a and 432a is suppressed and drainage is improved ([0024]).
Therefore, it would have been obvious before the effective filing date of the claimed invention that one of ordinary skill in the art would modify the distributor plate of modified Kongkanand to include at least two secondary channels (15) that intersect in order to improve drainage ([0024]).
Claims 3 and 4 are rejected under 35 U.S.C. 103 as being unpatentable over Kongkanand, as modified by Kato, as applied to claim 1 above, and further in view of Blanchet et al. (US 20100009233 A1).
Regarding claim 3, Kongkanand, as modified by Kato, teaches all limitations of claim 1 as stated above. Modified Kongkanand does not teach a limitation wherein the bridges (12) each comprise a contact region (47) and the at least one secondary channel (15) is completely covered by the coating (37) in the contact regions (47).
However, Blanchet teaches this limitation. Specifically, Blanchet teaches a formed metal sheet 102 that may include ridges, grooves, indentations, protrusions, or channels for fluid passages ([0005, 0023, 0028-0030]). Blanchet further teaches a porous spacer 107 disposed adjacent to and contacting the formed metal sheet 102 ([0044], Fig. 3). Under the broadest reasonable interpretation, the porous spacer 107 constitutes an overlying coating or layer. Because the porous spacer overlies the surface of the formed metal sheet, including any grooves or channels formed therein, the grooves or channels are completely covered by the porous layer in the contact region between the porous spacer 107 and the formed metal sheet 102. Blanchet further teaches that this structure improves fluid transport, and maintain electrical contact between adjacent fuel-cell components ([0019]).
Further, modified Kongkanand and Blanchet are considered to be analogous to the claimed invention because both references are directed to fuel-cell bipolar plate structures and to improving fluid transport within fuel-cell flow fields.
Therefore, it would have been obvious before the effective filing date of the claimed invention that one of ordinary skill in the art would modify the distributor plate of modified Kongkanand to provide an overlying porous layer covering the secondary channels as taught by Blanchet in order to improve fluid transport, and maintain electrical contact between adjacent fuel-cell components ([0019]).
Regarding claim 4, Kongkanand, as modified by Kato, teaches all limitations of claim 1 as stated above. Modified Kongkanand does not teach a limitation wherein the coating (37) is only partially porous, and a porous region (150) of the coating (37) is arranged at least partially on the at least one secondary channel (15).
However, Blanchet teaches this limitation. Specifically, Blanchet teaches a porous spacer 107 disposed adjacent to and contacting formed metal sheet 102 ([0044], Fig. 3). Blanchet further teaches that the spacer may comprise a porous structure having openings that permit fluid passage therethrough ([0009, 0022, 0024, 0026]). In particular, Blanchet teaches that an expanded metal mesh comprises rows of diamond-shaped openings that are offset from one another, thereby creating an uneven structure ([0024]). Under the broadest reasonable interpretation, such an uneven porous structure suggests regions having differing porosity characteristics and therefore renders obvious a coating that is only partially porous.
Under the broadest reasonable interpretation, porous spacer 107 constitutes the claimed coating (37), and the openings and porous portions of spacer 107 correspond to the claimed porous region (150). Because porous spacer 107 overlies formed metal sheet 102, including any grooves or channels formed therein [0028], the porous regions of spacer 107 are arranged over the grooves or channels, corresponding to the claimed secondary channels. Blanchet further teaches that this structure improves fluid transport, and maintain electrical contact between adjacent fuel-cell components, ([0019]).
Further, modified Kongkanand and Blanchet are considered to be analogous to the claimed invention because both references are directed to fuel-cell bipolar plate structures and to improving fluid transport within fuel-cell flow fields.
Therefore, it would have been obvious before the effective filing date of the claimed invention that one of ordinary skill in the art would modify the distributor plate of modified Kongkanand to provide an overlying partially porous layer having porous regions positioned over the secondary channels, as taught by Blanchet, in order to improves fluid transport, and maintain electrical contact between adjacent fuel-cell components ([0019])
Claims 6 and 13 are rejected under 35 U.S.C. 103 as being unpatentable over Kongkanand, as modified by Kato, as applied to claims 1 and 5 above, and further in view of Wang et al. (CN 111600045 A, as cited in the IDS filed 03/22/2024, citations from enclosed machine translation).
Regarding claim 6, Kongkanand, as modified by Kato, teaches all limitations of claim 1 as stated above. Modified Kongkanand does not teach a limitation wherein the at least one secondary channel (15) has a straight path.
However, Wang teaches this limitation (page 3, lines 34-40; Figs. 1, 3). Specifically, Wang teaches capillary grooves 40 disposed on the flow channel ridges 20, wherein the capillary grooves include rectangular grooves 41 extending in the length direction of the flow channel ridge 20 (page 3, lines 34-40; Figs. 1, 3). The rectangular grooves 41 are linear grooves and therefore teach a secondary channel having a straight path.
Wang further teaches that providing the capillary grooves on the flow channel ridges improves the water carrying capacity and water discharge efficiency of the fuel cell (page 3, lines 14-20; page 2, lines 32-39).
Further, modified Kongkanand, and Wang are considered to be analogous to the claimed invention because both are directed to fuel-cell separator/bipolar plate structures and, to improving water management and drainage in fuel-cell flow fields.
Therefore, it would have been obvious before the effective filing date of the claimed invention that one of ordinary skill in the art would modify the secondary channels of modified Kongkanand to have a straight path as taught by Wang in order to improve water carrying capacity and water discharge efficiency (page 3, lines 14-20; page 2, lines 32-39).
Regarding claim 13, Kongkanand, as modified by Kato, teaches all limitations of claim 5 as stated above. Modified Kongkanand does not teach a limitation wherein the at least one secondary channel (15) extends to the base surface (33) of a main channel (11).
However, Wang teaches this limitation (page 3, lines 22-25; page 2, lines 9-16; Fig. 3). Specifically, Wang teaches that the capillary groove 40 includes a right-angled triangular groove 42 located at the lower portion of the flow channel ridge 20, and that the right-angled triangular groove 42 is connected to the bottom of the flow channel groove (runner groove) 30 (page 3, lines 22-25; page 2, lines 9-16; Fig. 3). Thus, Wang teaches a secondary channel extending from the ridge to the base surface of the main channel.
Wang further teaches that providing the capillary grooves on the flow channel ridges improves the water carrying capacity and water discharge efficiency of the fuel cell (page 3, lines 14-20; page 2, lines 32-39).
Further, modified Kongkanand, and Wang are considered to be analogous to the claimed invention because both are directed to fuel-cell separator/bipolar plate structures and, to improving water management and drainage in fuel-cell flow fields.
Therefore, it would have been obvious before the effective filing date of the claimed invention that one of ordinary skill in the art would modify the distributor plate of modified Kongkanand, such that at least one secondary channel extends to the base surface of the main channel as taught by Wang in order to improve drainage and water discharge efficiency (page 3, lines 14-20; page 2, lines 32-39).
Claims 8 are rejected under 35 U.S.C. 103 as being unpatentable over Kongkanand, as modified by Kato, as applied to claim 1 above, and further in view of Kim et al. (KR 20190011929 A, as cited in the IDS filed 03/22/2024, citations from enclosed machine translation).
Regarding claim 8, Kongkanand, as modified by Kato, teaches all limitations of claim 1 as stated above. Modified Kongkanand does not teach a limitation wherein the top surface (13) comprises at least one first secondary channel (15, 152) and at least one second secondary channel (15, 154), wherein the at least one first secondary channel (15, 152) is arranged substantially parallel to the main channels (11) and the at least one second secondary channel (154) is arranged substantially orthogonally to the main channels (11).
However, Kim teaches this limitation ([0037, 0041]). Specifically, Kim teaches first groove portions 311 and second groove portions 321 for guiding generated water in a predetermined direction ([0037, 0041]). Kim further teaches that the first and second groove portions may extend along the same direction or along different directions ([0048-0049]), thereby demonstrating that the orientation of the groove portions is variable and selectable depending on design requirements.
Kim additionally teaches that such groove arrangements improve water discharge performance and maintain or improve contact resistance ([0008, 0027, 0057]).
Further, modified Kongkanand and Kim are considered to be analogous to the claimed invention because both references are directed to fuel-cell separator/bipolar plates and address water management.
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 distributor plate of modified Kongkanand to include first and second secondary channels having different orientations relative to the main channels, including parallel and orthogonal orientations, as suggested by Kim, in order to improve water discharge performance and maintain or improve contact resistance ([0008, 0027, 0057]).
Moreover, Kim's teaching that the groove portions may extend in the same or different directions demonstrates that the arrangement and orientation of the secondary channels are matters of routine design choice. Selecting parallel and orthogonal channel orientations would have involved only the rearrangement of known elements to obtain predictable results and, therefore, would have been obvious to one of ordinary skill in the art. See MPEP 2144.04(VI)(C).
Conclusion
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.
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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.
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/LILI RASSOULI/ Examiner, Art Unit 1728
/MATTHEW T MARTIN/Supervisory Patent Examiner, Art Unit 1728
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