DETAILED ACTION
Continued Examination Under 37 CFR 1.114
1. 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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 submissions filed on 8/14/2025, 10/21/2025, and 2/9/2026 have been entered.
The present application is being examined under the pre-AIA first to invent provisions. The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Election/Restriction
2. Applicant elects, without traverse, Invention I, Claims 1-7, 21-22, 29-34 in the responses filed 10/21/2025 and 2/9/2026. Applicant elects, without traverse, the following from the Species section on 2/9/2026.
Species A -the porous metal foam of the anode is made of titanium or its alloy (claims 3, 4, 29, 32, 41).
Species B- the porous metal foam of the cathode is made of titanium or its alloy
Species C- the catalyst layer is selected as platinum-metal alloy from the groups named (selecting a specific, single option) from the groups named at claims 6-7
Species D- “regions of a catalyst constituent” is platinum
Claims 7, 30, 32, and 35-41 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected species or invention claims, there being no allowable generic or linking claim.
Clarity of the Record – Claim Interpretation
3. Claim 1 was amended (claim set filed 11/20/2024) to change the preamble from “a fuel cell” to a “a fuel cell device” which was previously rejected as failing the written description requirement. The original claims from parent application 13/930,887 as well as the instant application are drawn to a fuel cell. The instant application disclosure is drawn to a fuel cell (P16 of the PGPUB). It is entirely unclear what, if anything, is added to the claimed construct by changing the preamble from a fuel cell to a fuel cell device. Applicant makes not comment as to the support or reasoning behind such an amendment, wherein it is noted that a shift in invention is not permitted if that is the intent (MPEP 819). The terminology of a fuel cell device only appears in the background of the invention and describes a device that directly produces electricity from fuel sources by reacting with oxidants (P3). Applicant makes no comments or traversal of the rejection in the response filed. For compact prosecution purposes, the rejection under 35 U.S.C. 112(a) is withdrawn, and the claims will be examined consistent with this interpretation (a fuel cell device is the same as a fuel cell).
Claim Rejections - 35 USC § 112
4. The rejections of claim 1, and thus dependent claims 2-6, 21-22, 29, 31, and 33-34, and claim 21 from the Office Action mailed 2/14/2025 under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement are withdrawn.
The rejections of claim 1, and thus dependent claims 2-6, 21-22, 29, 31, and 33-34, and claim 21 from the Office Action mailed 2/14/2025 under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention are withdrawn in view of the claim amendments provided.
5. The rejections of claim 1, and thus dependent claims 2-6, 21-22, 29, 31, and 33-34; claim 29; claim 31; claim 33 under U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement are maintained from the Office Action mailed 10/8/2025. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
Applicant utilizes the terminology of “regions of a catalyst constituent” and “an ionomer channel” in the claims named above. The terminology of “regions of catalyst constituent” is not found anywhere in the disclosure, and “an ionomer channel” is only ever used once in the context of comparing the prior art GDL to the titanium metal foam GDL (Fig. 2; P44). The Examiner is entirely unclear as to whether the ionomer channel is achieved by/one in the same as the polymer electrolyte of the fuel cell, or if this is an entirely new entity. Neither the disclosure nor Applicant’s comments provided on 10/21/2025 explain how the newly added language is adequately supported. It is not clear how/if “regions of a catalyst constituent” differ from the already presented and required catalyst layer. It is also not clear whether the polymer electrolyte is one in the same as the now-claimed “an ionomer channel,” or how the ionomer channel is being achieved/provided if distinctive from the polymer electrolyte.
Furthermore, nowhere in the instant application is there a description that “a structure of the single layer of porous metal foam comprises regions of a catalyst constituent…” This is repeated in claims 29, 31, and 33 reciting “the regions of catalyst constituent of the single layer of porous metal foam.” The instant application does not describe that the catalyst layer or regions thereof is comprised by the single layer of porous metal foam. At best, P44 teaches, “the platinum catalyst is between regions of titanium metal foam and ionomer channel.” P28 teaches that the polymer electrolyte layer is first bonded with the catalyst layer, which is then attached to the porous metal foam as a gas diffusion layer, and P71 teaches that the order of attachment may be reversed. Fig. 3 illustrates the titanium foam as anode GDL that is stacked on catalyst layer and Nafion membrane 304 (i.e., the polymer electrolyte, also termed “an ionomer channel” by Applicant in the claims). Accordingly, Applicant has not made clear how the newly added language is supported by the written description.
It thus remains unclear how the porous metal foam comes to comprise “regions of a catalyst constituent” (that differ from the already defined catalyst layer) between the metal foam and an ionomer channel (that somehow either differs from the already defined polymer electrolyte or is an all-together new entity). Applicant’s explanation provided on 10/21/2025 reproduces P5, 28, and 44 with emphasis added to in certain sections; however, none of these sections recites the newly added limitations of the subject matter added to claim 1, nor is there any explanation beyond “…one of ordinary skill in the art would appreciate the subject matter recited in the claims.”
Additionally, “regions of a catalyst constituent” requires that there are distinctive regions (plural). No such teaching exists in the instant disclosure. There is a catalyst layer defined in the instant application; the instant application does not describe that it contains distinctive regions of catalyst constituent.
Accordingly, the claim amendments violate the written description requirement for the myriad of reasons explained above.
It is noted that this rejection was presented in the Restriction Requirement mailed 10/8/2025 with a note (see page 5) pertaining to Species D on this matter. Applicant elects different species for the catalyst layer (Species C- platinum-metal alloy) and the regions of a catalyst constituent (Species D- platinum). If these are one in the same entity, it is not clear how they can be distinctive chemical species. Accordingly, the subsequent response should adequately explain how the catalyst layer is somehow distinctive from “regions of a catalyst constituent” such that the catalyst layer can be a platinum-metal alloy, while the “regions of a catalyst constituent” is somehow just platinum.
As explained above, it appears these are (maybe) the same entity such that appropriate amendments are required within the claims, with either:
1) an admission that platinum and all platinum-metal catalysts are obvious variants of one another (see pages 7-8 of restriction requirement mailed 10/8/2025); or
2) a single election made for both of Species C and D from the options of platinum or one of the specific platinum-metal catalysts as defined in claims 6, 31, and 33.
If the latter is elected (i.e., the genus of “a platinum-metal catalyst”), an appropriate species election would be for example, a “platinum-copper alloy catalyst” (i.e., one of the species of claims 6; see also the distinctive options sets forth in claims 31 and 33 as other choices of species of the genus “platinum-metal alloy”). The Examiner noted that a specific, single option should be selected in the original restriction requirement mailed (see page 5, reproduced below with emphasis added); however, this was not done in the responses filed on 10/21/2025 or 2/9/2026:
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A Notice of Non-Compliance was previously mailed on 11/25/2025 regarding the failure to appropriately elect species from the restriction requirement; it is noted that an additional failure to elect an actual species that is not a genus option will result in a Notice of Non-Compliance with no new time period for reply.
Appropriate correction or explanation is required.
6. Claim 5 and claim 22 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention.
A) Claim 5 as amended recites:
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The Examiner has reviewed the cited support (Applicant lists Figures 2, 3, 4A, 4B and P50, 54, and 79-92) and no such language exists. Accordingly, per Hyatt v. Dudas, 492 F.3d 1365, 1370, n.4 (Fed. Cir. 2007), is sufficient to make such a rejection:
Hyatt v. Dudas, 492 F.3d 1365, 1370, n.4 (Fed. Cir. 2007) (citing MPEP § 2163.04 which provides that a "simple statement such as ‘applicant has not pointed out where the new (or amended) claim is supported, nor does there appear to be a written description of the claim limitation in the application as filed’ may be sufficient where the claim is a new or amended claim, the support for the limitation is not apparent, and applicant has not pointed out where the limitation is supported.")
As previously noted, future claim amendments should be accompanied with comments that specifically point out support for any claim amendments (MPEP 2163, section 3(b); MPEP § 714.02; and MPEP § 2163.06). An appropriate example of support citation would be to map the newly added or amended claim to a specific paragraph number of the disclosure (e.g., claim 1 is supported at P32, claim 13 is supported at P45, etc.). If the newly added limitation is solely found in the drawing, then an appropriate corresponding explanation is required if the feature is not immediately apparent.
With respect to the newly added limitations of claim 5, a newly added range with no upper bound violates the written description (see In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976)- a corresponding new claim limitation of "at least 35%" did not meet the description requirement because the phrase "at least" had no upper limit and caused the claim to read on embodiments not described). Thus, “at least 462 mA/cm2” and “at 0.7 volts and above” as newly recited are both problematic.
At best, Fig. 4A appears to be the only relevant description of the claimed feature, and this is highly confusing given the use of oxygen flowed to the anode. In a fuel cell device, oxygen is not flowed to the anode but rather the cathode; this is taught in Applicant’s own disclosure (P79-81), as well as evidenced by the prior art (Kinkelaar et al. – US 2004/0001993 – P2-3). Accordingly, an appropriate explanation of how this fuel cell with oxygen flowing to the anode is operating to achieve the described current densities is required.
Lastly, it is not clear from this figure how Applicant obtained the starting value of 462 mA/cm2 at 0.7 volts and above as claimed given at 0.7 volts. There are confusingly two Ti foam lines (this in itself is not clear), and both values (partially obstructed from view in the lower line which is also problematic) appear to be well beyond a starting value of 462 mA/cm2.
Thus, claim 5 is not considered to meet the written description requirement for the myriad of reasons listed above.
B) Claim 22 recites, “a thickness of the single layer of porous metal foam is at least about 100 microns.” The Examiner has reviewed the cited support (Applicant lists Figures 2, 3, 4A, 4B and P50, 54, and 79-92) and no such language exists. The cited paragraph numbers do not teach the feature; a word search of the entire document also does not produce any hits for the language. Thus, claim 22 is not considered to meet the written description requirement.
Appropriate correction is required.
7. Claim 1, and thus dependent claims 2-6, 21-22, 29, 31, and 33-34; claim 21; and claim 22 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
A) Claim 1 as amended recites that there are “regions of a catalyst constituent” in between metal foam and an ionomer channel. “Ionomer channel” is only ever used once in the context of comparing the prior art GDL to the titanium metal foam GDL (Fig. 2; P44). The Examiner is entirely unclear as to whether the ionomer channel is achieved by/one in the same as the polymer electrolyte of the fuel cell or if this is an entirely new entity. Neither the disclosure nor Applicant’s comments provided on 10/21/2025 explain how the newly added language is adequately supported or definitive. It is not clear whether the polymer electrolyte is one in the same as the now-claimed “an ionomer channel,” or how the ionomer channel is being achieved/provided if it is distinctive from the polymer electrolyte. The disclosure is not illuminating on the matter; accordingly the meaning of the term in the context of the claim is not clear and renders the claim indefinite.
B) Claim 21 utilizes the relative term of degree of “a few” which renders the claim indefinite. A few is a relative term not defined in the specification, wherein there is no standard in the prior art for this feature. Accordingly, the use thereof renders the claim indefinite because there is nothing in the specification or prior art to provide any indication as to what range is covered by the term "a few" (see Amgen, Inc. v. Chugai Pharmaceutical Co., 927 F.2d 1200, 18 USPQ2d 1016 (Fed. Cir. 1991) (MPEP 2173.05(b)].
It is noted that the use of approximation terms or terms of degree such as “a few” are not indefinite when the specification provides some standard allowing for one of ordinary skill in the art to understand the scope of the term. If the specification does not provide some standard for measuring that degree, a determination must be made as to whether one of ordinary skill in the art could nevertheless ascertain the scope of the claim (e.g., a standard that is recognized in the art for measuring the meaning of the term of degree). For example, in Ex parte Oetiker, 23 USPQ2d 1641 (Bd. Pat. App. & Inter. 1992), the phrases "relatively shallow," "of the order of," "the order of about 5mm," and "substantial portion" were held to be indefinite because the specification lacked some standard for measuring the degrees intended. The meaning of every term used in a claim should be apparent from the prior art or from the specification and drawings at the time the application is filed. Claim language may not be "ambiguous, vague, incoherent, opaque, or otherwise unclear in describing and defining the claimed invention." Packard, 751 F.3d at 1311.
In the instance scenario, there specification fails to make clear what would or would not be covered by “a few.” Is three considered a few? Four? Five? The answer is not clear, nor where the delineation between when the claim is met and it is not. The Examiner recommends using the language of original claim 17 to overcome this rejection.
C) Claim 22 recites “at least about 100 microns.” The use of “about” is a relative term of degree and renders the claim indefinite for the same reasons outlined in section B above for “a few.”
Appropriate correction is required. The claims will be interpreted as best as possible for prior art application in view of the issues outlined above.
Claim Objections
8. The prior Office Action objections to claims 2-7 and 22-33 are withdrawn in view of the corrections provided.
9. Claims 4 and 21 are objected to because of the following informalities. Claim 4 recites “wherein the gas diffusion layer is porous titanium foam.” This should be corrected to, “the single layer of porous metal foam comprises titanium” for clarity. Otherwise, the claims fail to invoke proper antecedent basis. The same issue is present in claim 21 and requires correction to invoke proper antecedent basis.
Appropriate correction is required.
Claim Rejections - 35 USC § 102
10. The rejection of claims 1, 3-6, and 21 under pre-AIA 35 U.S.C. 102(b) as being anticipated by Kume et al. (US 2009/0023047) is withdrawn. All rejections pending from this are also withdrawn.
The rejection of claims 1-6, 27-29, and 31-33 under pre-AIA 35 U.S.C. 102(b) as being anticipated by Kinkelaar et al. (US 2004/0001993) is withdrawn.
11. Claims 1, 2, 6, and 31 are rejected under pre-AIA 35 U.S.C. 102(b) as being anticipated by Hirakimoto et al. (US 2012/0129077).
Regarding claim 1, Hirakimoto teaches a fuel cell device (Fig. 4) comprising:
a polymer electrolyte 23 (P20, 41-57), a gas diffusion layer 24a (P61-70), and a catalyst layer 22a, wherein the GDL 24a is an anode of the fuel cell device (P61-70; Figs. 4-5), the anode comprises a single layer of porous metal foam (P57). Figure 4 is reproduced below:
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Applicant adds the language of, “…and a structure of the single layer of porous metal foam comprises regions of a catalyst constituent in between metal foam and an ionomer channel” which has rejections against it under both 35 U.S.C 112, first and second paragraphs. For compact prosecution purposes, the Examiner is utilizing the support for the amendment described by Applicant as provided on 10/21/2025 to interpret the language.
In said response, Applicant reproduces paragraphs 5, 28, and 44 with the following original emphasis:
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Hirakimoto teaches the GDL transports incoming reactant gases from the fuel supply section (P63-64)(i.e., the emphasized portion of P5 above1). Hirakimoto teaches the GDL first being bonded with the catalyst layer 15 and then attached to the polymer electrolyte membrane 16 (P68-69):
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Hirakimoto teaches that the catalyst layer 22a is between the anode GDL 24a and the polymer electrolyte membrane 23 (Fig. 4).
Accordingly, Applicant alleges that “one of ordinary skill in the art would appreciate the subject matter presented in the claims” (i.e., “a structure of the single layer of porous metal foam comprises regions of a catalyst constituent in between metal foam and an ionomer channel”) from a fuel cell meeting P5, 28, and 44 (response filed 10/21/2025), such that all structure set forth in the claim is considered met based on the Examiner’s best understanding of the newly added limitation in view of Applicant’s explanation.
Regarding claim 2, Hirakimoto fails to disclose a manufacturing process to form the single layer of porous metal foam; however, the claim is entirely a product-by-process claim that does not lend itself to any additional structural requirements, wherein the patentability of a product does not depend on its method of production (In re Thorpe, 777 F.2d 695, 698, 227 USPQ 964, 966 (Fed. Cir. 1985); MPEP § 2113). Accordingly, the method of making does not lend any further structure to the product claim such that single layer of porous metal foam is considered to provide the same structure implicit to the methods recited.
Regarding claim 6 and 31, Hirakimoto teaches the catalyst and “regions of the catalyst constituent” may comprise platinum or platinum alloys such as platinum-palladium alloy (P194).
Claim Rejections - 35 USC § 103
11. Claims 1-5, 22, and 29 are rejected under pre-AIA 35 U.S.C. 103(a) as being unpatentable over Kinkelaar et al. (US 2004/0001993) in view of Gyoten et al. (US 6,881,510).
Regarding claim 1, Kinkelaar teaches a fuel cell device 10 (P43; Fig. 2) comprising:
a polymer electrolyte 16 (P6), a gas diffusion layer (GDL) 13, and a catalyst layer 15 (P43), wherein the gas diffusion layer (GDL) (13) is an anode of the fuel cell device 102, and the GDL/anode 13 comprises a single layer of porous metal foam (P20-28, 43-50, 55; Fig. 2).
Fig. 2 of Kinkelaar is reproduced below:
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Applicant adds the language of, “…and a structure of the single layer of porous metal foam comprises regions of a catalyst constituent in between metal foam and an ionomer channel” which has rejections against it under both 35 U.S.C 112, first and second paragraphs. For compact prosecution purposes, the Examiner is utilizing the support for the amendment described by Applicant as provided on 10/21/2025 to interpret the language.
In said response, Applicant reproduces paragraphs 5, 28, and 44 with the following original emphasis:
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Kinkelaar teaches the GDL transports incoming reactant gases from the bipolar plates/separators (P5, 9, 35, 45, 47) (i.e., the emphasized portion of P5 above3). Kinkelaar teaches that the catalyst layer 15 is between the anode GDL 13 and the polymer electrolyte membrane 16 (Fig. 2; P43-47) (i.e., the emphasized portion of P44 above).
Kinkelaar teaches the scope of the method of making a combination comprising a GDL/anode 13 that is adjacent to and in contact with the catalyst layer 15 of the fuel cell (P33). Thus, the single layer of porous metal foam is not taught as first being bonded with the catalyst layer 15 and attached to the polymer electrolyte membrane 16 (emphasized portion of P28); however, such a method step is standard and routine in the state of the prior art as taught by Gyoten.
Specifically, Gyoten teaches analogous art in the same field of endeavor of a polymer electrolyte fuel cell and that it is a known technique to first bond the catalyst layer to the porous GDL and then attach it to the PEM (C1/L22-40):
A polymer electrolyte fuel cell is fabricated in the following manner. First, a paste for catalyst layer, prepared by mixing a dispersion of the above-described polymer electrolyte with a carbon powder carrying a platinum-based metal catalyst, is applied onto both surfaces of a membrane of this polymer electrolyte, and the whole was dried to form a catalyst layer, which will constitute electrodes (a cathode as an air electrode and an anode as a fuel electrode). On the outer surface of the catalyst layer, a porous conductive substrate such as a carbon paper is disposed as a gas diffusion layer, which will constitute the electrodes, for diffusing air and a fuel gas. In other words, the catalyst layer and the gas diffusion layer constitute the electrodes. Alternatively, the paste for catalyst layer may be applied onto the carbon paper constituting the gas diffusion layer, and the polymer electrolyte membrane may be bonded to this. This yields an electrolyte membrane-electrode assembly (MEA) comprising the polymer electrolyte membrane, catalyst layer and gas diffusion layer.
Therefore, it would have been obvious to one having ordinary skill in the art at the time of the invention to provide the known technique taught by Gyoten of first bonding the catalyst layer 15 to the porous GDL 13 and then attaching it to the PEM 16 in order to provide a known means by which the desired combination taught by Kinkelaar of a combination GDL 13 and catalyst 15 is achieved (P33), the known technique applied to the construct of Kinkellar producing the predictable results of enhanced bonding/joining of components to one another to promote electrical and ionic conduction throughout the multi-layer construct.
Applicant alleges that “one of ordinary skill in the art would appreciate the subject matter presented in the claims” (i.e., “a structure of the single layer of porous metal foam comprises regions of a catalyst constituent in between metal foam and an ionomer channel”) from a fuel cell meeting P5, 28, and 44 (response filed 10/21/2025), such that all structure set forth in the claim is considered met based on the Examiner’s best understanding of the newly added limitation in view of Applicant’s explanation.
Regarding claim 2, Kinkelaar teaches wherein a manufacturing process to form the single layer of porous metal foam comprises at least one of the following: electroplating and electroless plating (P27). Although the manufacturing process is taught by Kinkelaar (P27), it is noted that the claim is entirely a product-by-process claim that does not lend itself to any additional structural requirements, wherein the patentability of a product does not depend on its method of production (In re Thorpe, 777 F.2d 695, 698, 227 USPQ 964, 966 (Fed. Cir. 1985); MPEP § 2113).
Regarding claim 3, Kinkelaar teaches wherein the porous metal foam is made of titanium and its alloys4 (P25, 50).
It is noted that Kinkelarr also teaches the use of the following metal and its alloys: platinum, palladium, titanium, nickel, copper, aluminum, zirconium, tungsten, cobalt, manganese, magnesium, bismuth, chromium, silver, gold, niobium, tantalum, silicon, iridium, indium, molybdenum, zinc, tin, antimony, and stainless steel (P25, 50, 55).
Regarding claim 4, Kinkelaar teaches wherein the gas diffusion layer 13 is porous titanium foam (P14, 25, 50).
Regarding claim 5, Kinkelaar as modified by Gyoten teaches a fuel cell device with all positively recited structure of claims 1 and 4 on which it depends. It is considered inherent to the construct, having all the same structure recited in the claim, that the result-obtained claimed would naturally flow therefrom. If Applicant alleges that inherency does not hold true, then the claims would be subject to a 35 U.S.C. 112(b) rejection on the basis of reciting a result-obtained limitation for which the structure is not clear from the claim terms (see MPEP 2173.05(g)5).
Alternatively, it is noted that the goal of any fuel cell device is to provide the most current possible; accordingly, it is considered an entirely obvious expedient to one having ordinary skill in the art to configure the fuel cell device of Kinkelaar such that it achieving the highest amount of current possible (whether in terms of area or volume).
Regarding claim 22, Kinkelaar teaches wherein a thickness of the single layer of porous metal foam is in the range of 0.1 to 10 mm (=100 microns-10,000 microns) (P48). In the case where the claimed range overlaps or lies inside range(s) disclosed by the prior art a prima facie case of obviousness exists (see MPEP § 2144.05).
Regarding claims 29, Kinkelaar teaches wherein the porous metal foam comprises titanium (P25, 50), and the catalyst layer (“regions of the catalyst constituent of the single layer of porous metal foam” – see analysis above in claim 1) comprises platinum (P4, 44).
Claim Rejections - 35 USC § 103
13. Claims 6, 31, and 33 are rejected under pre-AIA 35 U.S.C. 103(a) as being unpatentable over Kinkelaar et al. (US 2004/0001993) in view of Gyoten et al. (US 6,881,510) as applied to at least claim 1 above, and further in view of Lopez et al. (US 2010/0086832).
Regarding claims 6, 31, and 33, Kinkelaar teaches wherein the catalyst layer is selected from a group of the following catalyst: platinum catalyst (P33). Kinkelaar does teach the selected genus of the catalyst layer is a platinum-metal catalyst (claim 6), or that the “regions of catalyst constituent” comprise a platinum-metal alloy with nickel, chromium, and copper as options of the metal (claim 316), or have the format of a metal-platinum core shell structured catalyst (claim 335).
In the same field of endeavor, Lopez teaches analogous art of core-shell catalyst suitable for use in a fuel cell and specifically PEM fuel cells (P1) that is based on a core/shell structure comprising a base metal core and a Pt-alloy shell (P48). The Pt-alloy is taught as including the examples of Pt/Ni, Pt/Cr, Pt/Ru or Pt/Cu, among others (P48). Lopez teaches the catalyst particles achieve a high specific activity (abstract, P2) and possess a low precious metal content due to the core/shell structure such that a reduction of (costly) precious metals is achieved (P6).
Therefore, it would have been obvious to one having ordinary skill in the art at the time of the invention to substitute the platinum catalyst of the PEM fuel cell of Kinkelaar with the core/shell structure taught by Lopez in which the shell includes a Pt-alloy such as Pt/Ni, Pt/Cr, Pt/Ru or Pt/Cu, among others (P48) in order to achieve the predictable, advantageous, taught results of providing a catalyst with high specific activity that allows for a reduction in precious metals (P2, 6).
14. Claim 21 is rejected under pre-AIA 35 U.S.C. 103(a) as being unpatentable over Kinkelaar et al. (US 2004/0001993) in view of Gyoten et al. (US 6,881,510) as applied to at least claims 1 and 4 above, and further in view of Perry et al. (US 2010/0330448).
Regarding claim 21, Kinkelaar teaches where the porous material forming the gas diffusion layer has a pore size in the range of 5-150 pores per linear inch before it is coated with the at least one electrically conductive material which may be titanium (P30). Accordingly, a final pore diameter of the porous titanium foam is not detailed; however, looking to known, suitable pore diameters for a gas diffusion layer having a similar or same construct, Perry teaches analogous art of a fuel cell with a single layer porous GDL functioning as an anode 38 adjacent anode catalyst 14, wherein the average pore diameter is taught as being 10-40 micrometers (P21).
Therefore, it would have been obvious to one having ordinary skill in the art at the effective filing date of the invention to look to known, suitable values or ranges taught by the prior art and adopt those for the final pore diameter of the GDL 13 of Kinkelaar, wherein Perry teaches an analogous construct and that a suitable pore average pore diameter for the anode GDL is 10-40 micrometers (P21). In the case where the claimed range overlaps or lies inside range(s) disclosed by the prior art a prima facie case of obviousness exists (see MPEP § 2144.05).
15. Claim 34 is rejected under pre-AIA 35 U.S.C. 103(a) as being unpatentable over Kinkelaar et al. (US 2004/0001993) in view of Gyoten et al. (US 6,881,510) as applied to at least claim 1 above, and further in view of Hiroshi et al. (JP 2001-057218) (machine translation provided).
Regarding claim 34, Kinkelaar teaches where the gas diffusion layer 13 is a “first gas diffusion layer” and the fuel cell device comprises:
a second gas diffusion layer 13A comprising a porous metal foam, wherein the second gas diffusion is a cathode of the fuel cell device.7
Kinkelaar fails to disclose the second (cathode) gas diffusion layer comprises larger pore diameters than the first (anode) gas diffusion layer as claimed.
In the same field of endeavor, Hiroshi teaches analogous art of a PEM fuel cell including an analogous construct of gas diffusion layers sandwiching respective catalyst layers with a central polymer electrolyte membrane, wherein Hiroshi teaches the average pore diameter of the anode GDL 1a is smaller than the average pore diameter of the cathode GDL 1b (abstract; P35, 40; full disclosure relied upon) in order to balance the water created as a byproduct at the cathode (P1-23, 40).
Therefore, it would have been obvious to one having ordinary skill in the art at time of the invention to provide the second (cathode) GDL 13A of Kinkelaar such that it comprises larger pore diameters than the first (anode) GDL 13 given Hiroshi teaches the technique and construct are known in the art and provide the advantageous, predictable result of balancing the water created as a byproduct at the cathode (P1-23, 40).
Response to Arguments
16. Applicant's arguments filed 8/14/2025 and 10/21/2025 have been fully considered. Any pertinent remaining prior art rejections not withdrawn from the prior Office Actions with remaining pertinent arguments are addressed here.
Applicant argues:
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In response: The claim requires a single layer of porous metal foam. The claim does not limit the single layer of porous metal foam to consisting of only metal. Accordingly, foams that include other materials in addition to metal are applicable to claims as presented. Accordingly, the rejection of Kinkelaar is maintained. For compact prosecution purposes, arguendo, even if such a limitation was made to the claims, it is noted that Hirakimoto et al. (US 2012/0129077) teaches a PEM fuel cell in which the gas diffusion layers 24a, 24b adjacent catalyst layers 22a, 22b, respectively, are made of a sintered metal or foam metal:
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For compact prosecution purposes, the claims anticipated by this reference are rejected above. It is noted that claims requiring additional secondary references are not applied; however, any reference used against the claims in other rejections thereof are certainly applicable. The rejection is made as a compact prosecution rejection.
Conclusion
17. The prior art made of record and not relied upon considered pertinent to applicant's disclosure is reproduced below:
With respect to a porous GDL first being bonded with the catalyst layer and attached to the polymer electrolyte membrane 16 (emphasized portion of P28 by Applicant which is alleged to provide the limitation presented), the technique is additionally taught by the following prior art references:
Noda et al. (US 2011/0262828):
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Sakai et al. (US 2010/0196785) teaches:
[0094] In method (c), bases such as carbon paper are used as the support bases in method (b), to form the gas diffusion layers 16a, 16b. After forming a laminated body with catalyst layers formed on support bases (gas diffusion layers) in the same manner as above, these are situated with their respective catalyst layers in contact with the polymer electrolyte membrane 12 and bonded by pressing. The support bases are allowed to remain, unlike in method (b), to obtain a MEGA having catalyst layers 14a, 14b and gas diffusion layers 16a, 16b situated in that order on either side of the polymer electrolyte membrane 12.
Furthermore, it would appear other known, similar methods such as thermocompression bonding of the three components as taught by Maeda et al. (US 2010/0239949) (P56) would also achieve the claimed feature.
In the instance that there is some separate entity that is the “an ionomer channel,” that can be adequately demonstrated as supported, Iisaka et al. (US 2009/0068525) teaches the use of a binder/buffer layer utilized to bond the interface between the GDL and the electrode catalyst in order to improve the bonding strength of these components (P37) “So that performance degradation in the fuel cell during operation was suppressed” (P71) with further explanation at P72.
With respect to the second (cathode) GDL comprises larger pore diameters than the first (anode) GDL (claim 34), see also the following relevant prior art:
Spink et al. (US 2009/0169941) - Spink teaches analogous art of a fuel cell with the same structure of the claim, namely a proton exchange membrane with an anode side 62 and a cathode side 63, wherein there is an anode fluid diffusion layer adjacent to the anode side 62 and a cathode fluid diffusion layer 70 positioned on the cathode side 63, the fluid diffusion layers being porous, electrically conductive entities such as porous titanium diboride (P36-37). Spink teaches that it is a known technique in the art to provide the pore sizes of either or both of the fluid diffusion layers as dissimilar when measured in any one of the X, Y, and/or Z axes (P38). Note that fluid describes a liquid or a gas.
Koehler et al. (US 2007/0202388) - Koehler teaches analogous art of a PEM fuel cell and that “particularly good performance values are obtained in a MEU [membrane electrode unit] or PEM fuel cell if the cathode gas diffusion layers have a larger pore volume than the anode gas diffusion layers” (P26). This is well known given the cathode has to deal with water creation as a result of the proton migrating across the PEM and meeting the oxygen on the cathode side and forming water (as taught by Spink – P37).
18. Any inquiry concerning this communication or earlier communications from the examiner should be directed to AMANDA J BARROW whose telephone number is (571)270-7867. The examiner can normally be reached Monday-Friday 9am - 6pm CST.
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/AMANDA J BARROW/ Primary Examiner, Art Unit 1729
1 It is noted it is not clear how this has any bearing on the amended limitation of the claim, although it is met by Kinkelaar.
2 Kinkelaar teaches the gas diffusion layer 13 is has a negative potential during operation and is part of the overall anode construct on the left side of the fuel cell 10 which achieves the oxidation half-reaction with hydrogen being supplied thereto (P4; entire disclosure relied upon). It is noted that although the gas diffusion layer 13 is not termed “an anode” by Kinkelaar, the anode side (i.e., left side of the fuel cell 10 in Fig. 2) of Kinkelaar on which the gas diffusion layer 13 exists has the exact same construct as that of the gas diffusion layer “characterized as an anode” of the instant disclosure such that the difference is entirely one of semantics/ word choice. It is common in the prior art to term any of the layers (e.g., catalyst layer, GDL, bipolar plate) existing on a given side of a PEM relative to the potential they exist at during operation. All of these layers on the left side of the PEM 16 exist at a negative potential and constitute part of the “anode” and may termed the anode catalyst layer, the anode GDL, the anode bipolar plate.
3 It is noted it is not clear how this has any bearing on the amended limitation of the claim, although it is met by Kinkelaar.
4 Elected Species A.
5 MPEP 2173.05(g): Examiners should consider the following factors when examining claims that contain functional language to determine whether the language is ambiguous: (1) whether there is a clear cut indication of the scope of the subject matter covered by the claim; (2) whether the language sets forth well-defined boundaries of the invention or only states a problem solved or a result obtained; and (3) whether one of ordinary skill in the art would know from the claim terms what structure or steps are encompassed by the claim.
6 The elected species for the “regions of catalyst constituent” (species D) is platinum; however, the elected species for the catalyst layer is platinum. Please see the rejection under 35 U.S.C. 112(b)/second paragraph as to how it is not clear how these selections can be different. Accordingly, for compact prosecution purposes, claims 31 and 32 are also examined presently until a definitive species election or an admission of obvious variants is made. Accordingly, depending on the election made, these claims may be withdrawn in the future.
7 See footnote 1; the constituents on the right side of PEM 16 constitute the cathode side and are at a positive potential such that the GDL 13A is a cathode as claimed.