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 04/17/2026 has been entered. The 35 USC 112(b) rejections of the previous Office action are overcome and are now withdrawn.
Response to Arguments
Applicant’s arguments with respect to claim(s) 1 and its dependent claims, being previously rejected over primary reference Nishimura, have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
The amended and newly recited limitations within independent claim 1 necessitated the updated search and grounds of rejection below.
Although no longer relied upon in the below rejection, the grouping of Nishimura flow channels into a plurality of groups as defined by Examiner in Nishimura Fig. 2 as annotated on page 5 of the 02/09/2026 Office action could easily be adjusted to include opposite-direction flow channels within the same grouping since Nishimura teaches the serpentine shape of the overall flow field. Also as shown in Nishimura Fig. 2 zoomed-in excerpts annotated by Examiner on page 6 of the 02/09/2026 Office action, the ribs having the generally U-curved shape forming the edge of the cited return groove portions amounts to more than chamfered edges, and the U-shape met the relative distance limitations as previously claimed.
Claim Objections
Claims 2-3 (and their dependent claims 6-7) are objected to for the following informalities:
Claims 2 and 3 each recite the limitation "an end portion of the flow groove portions". However, base claim 1 previously introduces “an end portion of each of the plurality of flow groove portions”. Therefore, it is not understood whether claims 2-3 refer back to the same or different “an end portion”.
Appropriate correction is required. Claim 2 could likely be corrected to recite: “an end portion of the inflow groove portion”, while claim 3 could likely be corrected to recite “an end portion of the outflow groove portion” to eliminate the confusion caused by referring back to “of the flow groove portions” (since claim 2 positively introduces said “inflow groove portion”, and claim 3 positively introduces said “outflow groove portion”).
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.
Claim(s) 1-2 and 4-6 is/are rejected under 35 U.S.C. 103 as being unpatentable over Nomura et al. (US 20030215694 A1) in view of Shibuya (US 20140295322 A1, cited in the 04/12/2022 IDS and 02/09/2026 Office action).
Regarding claim 1, Nomura teaches a fuel cell (within fuel cell stack 15, [0040] and Fig. 1), the fuel cell comprising:
a fuel electrode (electrode formed on one face of the electrolytic membrane 1 is an anode, [0038]; supplying the anode with fuel gas (hydrogen), [0006]) that includes a fuel electrode catalyst layer (electrodes 2 and 44 are mainly made from carbon, into which platinum as a substance serving as a catalyst is mixed, [0038]), a fuel electrode diffusion layer (diffusion layer 45 at hydrogen flow side 48, Fig. 4 and [0044]), and a fuel electrode current collector (hydrogen separator 46, Fig. 4; see also hydrogen separator 9 in [0040] wherein hydrogen is used as the fuel gas 9a per [0038]);
an air electrode (electrode formed on the other face of the electrolytic membrane 1 is a cathode, [0038]; supplying the cathode with oxidative gas (oxygen, usually air), [0006]) that includes an air electrode catalyst layer (electrodes 2 and 44 are mainly made from carbon, into which platinum as a substance serving as a catalyst is mixed, [0038]), an air electrode diffusion layer (diffusion layer 3 at air flow side 18, Fig. 4 and [0044]), and an air electrode current collector (air separator 8, Fig. 4); and
an electrolyte membrane that is disposed between the fuel electrode catalyst layer and the air electrode catalyst layer (the MEA 7 is composed of an electrolytic membrane 1 and electrodes 2 and 44, electrolytic membrane 1 is pervious to hydrogen ions, each of the electrodes 2 and 44 is formed on a corresponding one of faces of the electrolytic membrane 1; [0038] and Fig. 4 showing laminated 44/1/2),
wherein the fuel electrode current collector includes:
a fuel inflow port to which the fuel is supplied (fuel gas 9a is introduced into its flow channel through a hydrogen-feed manifold 19, [0039] and Fig. 1);
a fuel outflow port from which the fuel is discharged (the fuel gas 9b is discharged through exhaust manifold 55, [0041] and Fig. 1); and
a fuel flow groove that is formed on a fuel flow surface (a hydrogen flow channel through which the fuel gas 9a flows is formed in a back face of the hydrogen separator 9, [0040]; see also [0044] regarding the hydrogen separator 46 constituting the hydrogen flow channel 47) on a side abutting the fuel electrode diffusion layer (Fig. 4 shows 47 as groove in 46 abutting diffusion layer 45; see also [0037] regarding channels formed in single separator face) and guides the fuel from the fuel inflow port to the fuel outflow port (flow channel connecting 19 to 55, Fig. 7; arrangement applied to hydrogen flow channel per [0052]),
wherein the fuel flow groove (see above citations – and see gas flow channels 66-67 arrangement in Figs. 1, 2C, and 3A which can also be applied to hydrogen flow channel per [0052], having “inverse S” and “S” shapes per [0034]) includes:
a plurality of flow groove portions (linear portions as shown in Fig. 2C) that extend from one side edge portion of the fuel flow surface to an other side edge portion opposite to the one side edge portion (horizontally, Fig. 2C in view of Fig. 1) and that are disposed in parallel at predetermined intervals (parallel at intervals in vertical direction, Fig. 2C in view of Fig. 1),
the plurality of flow groove portions divided into a plurality of groups adjacent to each other (each of 66 + 67 in Fig. 2C, plurality in Figs. 1 and 3Z) with directions of the fuel flowing in the plurality of flow groove portions being opposite (left-to-right [Wingdings font/0xE0] right-to-left [Wingdings font/0xE0] left-to-right from each of inlet portions 26 and 27 toward outlet portion 28, due to inverted S- and S-shapes of 66 and 67; see [0034] and Fig. 2C); and
a plurality of return groove portions (multiple portions 31, Figs. 1 and 3A in view of 2C) that connect an end portion of each of the plurality of flow groove portions of two adjacent groups among the plurality of groups (second curved portion 31 connecting 66+67 at upstream of 31 to the third linear portion 58 and the outlet portion 28 at downstream of 31, which constitute the common gas flow channel portions that belong to both the “inverse S”-shaped gas flow channel 66 and the S-shaped gas flow channel 67; [0034] and Fig. 2C),
wherein each of the plurality of return groove portions includes a first inner wall surface portion facing the end portion of each of the flow groove portions of the two adjacent groups (curved portion of 31 towards left in Fig. 2C, which faces each of: linear end portion 64 of 66 + linear end portion 65 of 67), and wherein
the first inner wall surface portion has a curved surface shape (31 is curved per [0034], Fig. 2C) in which a distance facing with each other from the first inner wall surface portion to the end portion of each of the flow groove portions of the two adjacent groups (inner wall of 31 facing rightward toward linear portions, Fig. 2C), gradually decreases toward both end portions of the first inner wall surface portion (curve of 31 approaches closer to ends of 64 and 65 within 66/67 than to 58 among the linear portions of the flow grooves, Fig. 2C) in a direction orthogonal to an extending direction of the flow groove portions (vertically, orthogonal to horizontal direction, Fig. 2C).
Nomura fails to teach the fuel cell being a direct liquid fuel cell in which a liquid containing a formic acid or an alcohol is used as a fuel; nor the above-cited separators being “a fuel electrode current collector” and “an air electrode current collector”, respectively.
Shibuya is analogous in the art of fuel cells and teaches a fuel cell being a direct liquid fuel cell (a direct methanol fuel cell, [0021]; DMFC, [0107]) in which a liquid containing a formic acid (formic acid is a by-product produced when hydrogen ions are produced from methanol on an anode catalyst, [0007]) or an alcohol is used as a fuel (methanol, [0021, 0077]). Shibuya also teaches that within a DMFC, the term “fuel cell separator” refers to a fuel cell separator which has electrical conductivity, collects energy (electricity) produced on each single cell, and that said separator is also referred to as a current collector ([0036]; see also current collector plates 140A/140B, [0078] an Fig. 3).
Shibuya teaches in [0077] that hydrogen is a fuel gas and methanol is a fuel liquid, both of which can serve as reaction fluids flowing within the fuel cell separator flow paths, and teaches in [0107] that the layered type fuel cell can be applied when either hydrogen or methanol is used as the fuel. Therefore, it would have been obvious for a person having ordinary skill in the art to substitute methanol as taught by Shibuya instead of hydrogen as the fuel within Nomura and expect a functional fuel cell stack (see MPEP 2143 I B), specifically a DMFC. Also, since Shibuya teaches that the “separators” within the direct methanol fuel cell are synonymous with “current collectors” which function to impart electrical conductivity and collect electricity produced by the electrodes of the cell, it would have further been obvious that the separators cited above would function within modified Nomura as current collectors to serve the necessary conduction and collection function of electricity produced within the DMFC cell stack.
Thereby, claim 1 is rendered obvious.
Regarding claim 2, modified Nomura teaches the limitations of claim 1 above and wherein
the fuel flow groove includes an inflow groove portion (inlets 26 + 27 connected to respective first linear portions 62 and 63, [0034] and Fig. 2C) that is connected to the fuel inflow port (26+27 would also connect to fuel feed manifold 19 per Fig. 3A in view of Fig. 1 and [0052]) on a side opposite to the a return groove portion of one group among the plurality of groups (26 and 27 farther to left side than 31 and face oppositely [left] versus inner wall of curved portion 31 [facing right], Fig. 2C), the one group of the plurality of flow groove portions being configured such that the fuel first flows therein (first flows into first linear portions 62/63 from 26/27, Fig. 2C – [0034] in view of [0052]), wherein
the inflow groove portion includes a second inner wall surface portion facing an end portion of the flow groove portions in the inflow groove portion (inner walls of first turn portions 29 + 30, [0034] and Fig. 2C), and wherein
the second inner wall surface portion has a curved surface shape (first curved portions 29 and 30, [0034]) in which a distance facing with each other from the second inner wall surface portion to the end portion of the flow groove portions in the inflow groove portion (curved inner walls of 29+30 facing leftward toward respective 66 and 67, Fig. 2C), gradually decreases toward an outflow side end portion of the second inner wall surface portion (29 curves closer to 62, 30 curves closer to 64; Fig. 2C) in a direction orthogonal to an extending direction of the flow groove portions (vertically, orthogonal to horizontal direction, Fig. 2C).
Regarding claim 4, modified Nomura teaches the limitations of claim 1 above and wherein the fuel flow groove includes a plurality of rib portions that are disposed between the plurality of flow groove portions (horizontally linear portions of separator between linear portions 58/62/63/64/65 of channels 66/67, Figs. 2-3 in view of 4 and [0034, 0052]), and wherein the plurality of rib portions have a plurality of protruding portions protruding in a circular arc shape in a plan view outward from the flow groove portions (see rounded tops of above-cited ribs in Fig. 2C), at the end portion of the flow groove portions of the two adjacent groups facing each of the first inner wall surface portion (two ribs extending toward/into 31 at left of Fig. 2C, thus forming 58 therebetween).
Regarding claim 5, modified Nomura teaches the limitations of claim 4 above and wherein the plurality of protruding portions protruding into the return groove portion portions (i.e., rounded tips of ribs between 64/58 and between 55/65 within 31, Fig. 2C) are formed such that a protruding height of the protruding portions gradually decreases from both of the end portions of the return groove portions (rounded shape of rib tips and rounded shape of 31 as cited above causes this decrease protruding height, Fig. 2C) in the direction orthogonal to the extending direction of the flow groove portions (vertical spacing of ribs to wall of 31, orthogonal to horizontal extending direction of linear portions; Fig. 2C) toward a boundary, at which a direction of the fuel flowing in the two adjacent groups is reversed (where flow direction reverses from 64 to 58 and from 65 to 58, Fig. 2C).
Regarding claim 6, modified Nomura teaches the limitations of claim 2 above and wherein the fuel flow groove includes a plurality of rib portions that are disposed between the plurality of flow groove portions (horizontally linear portions of separator between linear portions 58/62/63/64/65 of channels 66/67, Figs. 2-3 in view of 4 and [0034, 0052]), and
wherein the plurality of rib portions have a plurality of protruding portions protruding in a circular arc shape in a plan view outward from the flow groove portions, at the end portion of the flow groove portions in the inflow groove portion facing the second inner wall surface portion (rounded tip of rib between 62 and 64 protruding right toward 29, rounded tip of rib between 63 and 65 protruding right toward 30; Fig. 2C).
Claim(s) 3 and 7 is/are rejected under 35 U.S.C. 103 as being unpatentable over Nomura et al. (US 20030215694 A1) in view of Shibuya (US 20140295322 A1, cited in the 04/12/2022 IDS and 02/09/2026 Office action), and further in view of Rock (US 2003/0175577 A1).
Regarding claim 3, modified Nomura teaches the limitations of claim 1 above and wherein
the fuel flow groove includes an outflow groove portion (outlet portion 28 connected from third linear portion 58, [0034] and Fig. 2C) that is connected to the fuel outflow port (28 is a downstream outlet, [0034] and Fig. 2C; 55 is downstream exhaust manifold of fuel gas per [0041]; see also Fig. 1 in view of [0052]) on a side opposite to a return groove portion of one group among the plurality of groups (28 is opposite from 31 in horizontal direction at end of 58 which is connected to both 66+67, Fig. 2C), the one group of the plurality of flow groove portions being configured such that the fuel lastly flows therein (linear portion 58 is the last in the flow series per [0034] and Fig. 2C, where fuel gas 9b would flow per [0041] in view of [0052]), but fails to teach:
the outflow groove portion includes a third inner wall surface portion facing the an end portion of the flow groove portions in the outflow groove portion, and wherein
the third inner wall surface portion has a curved surface shape in which a distance facing with each other from the third inner wall surface portion to the end portion of the flow groove portions in the outflow groove portion, gradually decreases toward an inflow side end portion of the third inner wall surface portion in a direction orthogonal to an extending direction of the flow groove portions.
Rock is analogous in the art of fuel cell stacks with MEAs (PEM fuel cell stack having a pair of membrane-electrode-assemblies (MEAs), [0015]) and teaches various embodiments all having multiple serpentine flow field channels (Abstract and Figs. 2 and 4-7). Rock teaches each channel having an inlet leg, an exit leg, at least one medial leg therebetween, and hairpin curved ends connecting the medial leg(s) to other legs of the sector (abstract and [0006]). Rock at Figs. 4-7 show that per inlet 66a-L, there are five medial legs – which correspond to the “linear portions” of Nomura as cited above – and four connective hairpin U-turns – which correspond to the “curved portions” of Nomura as cited above. Rock [0005] teaches that the pressure drop between the supply manifold and the exhaust manifold is of considerable importance in designing a fuel cell and problems can arise if not designed properly. Rock teaches that the inventive design of multiple medial legs connected via multiple hairpin curves/reverse turns thus creating the serpentine flow field are beneficial to balance the pressure drop across the flow field ([0005-0006, 0017]).
It would have been obvious, at the time of filing, for a person having ordinary skill in the art to modify the flow channels of Nomura to include an additional linear portion connected by an additional curved portion within each flow group as taught by Rock with the motivation of achieving a well-designed flow field with balanced pressure. The resultant design of modified Nomura in view of Rock would therefore include “the third inner wall surface portion has a curved surface shape” and meet the relative distance claims along the curved third inner wall, consistent with first and second curved portions of Nomura corresponding to claimed first and second inner walls as cited above.
Thus, the instant claim 3 is rendered obvious.
Regarding claim 7, modified Nomura teaches the limitations of claim 3 above and wherein the fuel flow groove includes a plurality of rib portions that are disposed between the plurality of flow groove portions (horizontally linear portions of separator between linear portions 58/62/63/64/65 of channels 66/67, Nomura Figs. 2-3 in view of 4 and [0034, 0052] – see corresponding lands 64 between medial legs within Rock exemplary Fig. 5), and
wherein the plurality of rib portions have a plurality of protruding portions protruding in a circular arc shape in a plan view outward from the flow groove portions (see rounded tips of ribs protruding rightward and leftward around the linear/medial portions of Nomura and Rock as cited above), at the end portion of the flow groove portions in the outflow groove portion facing the third inner wall surface portion (additional/third inner wall as applied to Modified Nomura above; see rounded tip of all lands 64 facing the hairpin curves formed by the flow channels in Rock, including that corresponding to the third wall surface portion when applied to modified Nomura).
Relevant Prior Art
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure:
Rock (US 2003/0175577 A1, as cited above) teaches a fuel cell being a direct liquid fuel cell (PEM fuel cell stack having a pair of membrane-electrode-assemblies (MEAs), [0015]) in which a liquid containing … an alcohol is used as a fuel (hydrogen supplied to the anode from fuel processor which catalytically generates hydrogen from methanol, [0015]), the fuel cell comprising:
a fuel electrode (hydrogen supplied to the anode, [0016]) that includes a fuel electrode catalyst layer (fuel processor which catalytically generates hydrogen from methanol, [0015]), a fuel electrode diffusion layer (Porous, gas permeable, electrically conductive sheets 34, 36, 38 and 40, known as diffusion layers, press up against the electrode faces of the MEAs 4 and 6; [0015]), and a fuel electrode current collector (electrically-conductive anode current collector engaging the anode face, [0006]);
an air electrode (air is supplied to the cathode side from the ambient, [0015]) that includes an air electrode catalyst layer (anode and cathode films typically comprise catalytic particles, [0002]), an air electrode diffusion layer (Porous, gas permeable, electrically conductive sheets 34, 36, 38 and 40, known as diffusion layers, press up against the electrode faces of the MEAs 4 and 6; [0015]), and an air electrode current collector (electrically-conductive cathode current collector engaging the cathode face; [0006]); and
an electrolyte membrane that is disposed between the fuel electrode catalyst layer and the air electrode catalyst layer (a proton exchange membrane having opposing cathode and anode faces on opposite sides thereof, [0006]),
wherein the fuel electrode current collector (a current-collecting plate engaging at least one of the gas-permeable collectors and defining a gas flow field, [0006]; reactant gas flow field, [0016]) includes:
a fuel inflow port to which the fuel is supplied (inlet supply manifold 72, [0019] and Figs. 4-5);
a fuel outflow port from which the fuel is discharged (exhaust manifold 74, [0019] and Fig. 4); and
a fuel flow groove (flow channels 66 through which the fuel cell's reactant gas – e.g. H2 – flows, [0016]) that is formed on a fuel flow surface on a side abutting the fuel electrode diffusion layer (66 in the form of surface grooves per Fig. 3) and guides the fuel from the fuel inflow port to the fuel outflow port (flow channels 66 connecting 72 to 74 per Figs. 2 and 4) ,
wherein the fuel flow groove includes:
a plurality of flow groove portions (each from inlets 66a-66L, [0019] and Fig. 4) that extend from one side edge portion of the fuel flow surface to an other side edge portion opposite to the one side edge portion (Fig. 7 embodiment, [0021] – where 66 extend across H horizontally as shown in Fig. 7) and that are disposed in parallel at predetermined intervals (inlets to 66a-L are parallel and at intervals, Fig. 7 in view of Figs. 4-5),
the plurality of flow groove portions divided into a plurality of groups adjacent to each other (e.g., groupings within 66a-66L like shown in Fig. 4, but applied to single sector H in Fig. 7; plural sectors described in [0006]) with directions of the fuel flowing in the plurality of flow groove portions being opposite (serpentine sector(s), [0006] and Fig. 7 – see also annotation below); and
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a plurality of return groove portions that connect an end portion of each of the plurality of flow groove portions of two adjacent groups among the plurality of groups (reverse turn - e.g. hairpin curve - in the channel at each end of the medial leg(s) connects the medial leg(s) to adjacent legs of the same channel, [0006] and Fig. 7),
wherein each of the plurality of return groove portions includes a first inner wall surface portion facing the end portion of each of the flow groove portions (lands 64 from inner side of manifold 72 to hairpin turn ends of 66, illustrated in Fig. 5 but also applicable numbering to Fig. 7) of the two adjacent groups (e.g., 66a inlet group and 66b inlet group as shown in Fig. 5), and wherein
the first inner wall surface portion has a curved surface shape (shape of land 64 at left from inlet manifold 72 to hairpin turns in 66, as shown in Figs. 4-5 and annotated below in a Fig. 7 excerpt) in which a distance facing with each other from the first inner wall surface portion to the end portion of each of the flow groove portions of the two adjacent groups (two adjacent flow group inlets annotated below corresponding to above annotation of Fig. 7), gradually decreases toward both end portions of the first inner wall surface portion in a direction orthogonal to an extending direction of the flow groove portions (66 end turns become horizontally closer to edge of 64 at 72 along the vertical direction, as annotated in Fig. 7 excerpt below).
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Rock (US 6309773 B1) is similar to Rock (US 2003/0175577 A1) cited directly above but teaches all legs 76/78 forming adjacent flow grooves are parallel (Figs. 4-5), and still teaches the land 64 at the U-turn ends of 66 having a curved shape (can be seen in Fig. 5, and zoomed-in on Fig. 4).
Uozumi (US 4407904 A) teaches curved, U-shaped manifolds 22 and 23 around a fuel cell stack, with multi-direction flow therein (Figs. 7 and 10-11 – see flow arrows inside 22 and 23), thus corresponding to inner walls of return grooves.
Leger (US 20060234107 A1) teaches flow field plate 100 of a fuel cell having curved inlet apertures 126 with walls 120 and curved outlet apertures 128 with walls 122, and channels 150 running therebetween (Fig. 1).
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 Jessie Walls-Murray whose telephone number is (571)272-1664. The examiner can normally be reached M-F, typically 10-4.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Matthew 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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/JESSIE WALLS-MURRAY/Primary Examiner, Art Unit 1728
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