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 Arguments
Applicant’s arguments, see page 13, filed 6 August 2026, with respect to di Iorio et al have been fully considered and are persuasive. The rejections of all claims set forth in the Office action mailed 18 May 2026 have been withdrawn.
Note that the withdrawal is based upon Applicant’s persuasive remarks regarding the abutment of the unipolar plates of each substack. Di Iorio et al clearly teach placing intervening structures (seals 6.1, 6.2, electrical contact members 5.1, 5.2) between adjacent substacks.
Since di Iorio et al failed to teach that a unipolar plate abutted the unipolar plate of the adjacent substack, the rejection grounds for claim 23 previously set forth are now considered to have been deficient. Thus, the new grounds of rejection for claim 23 below are not necessitated because of Applicant’s amendment, although an amendment was made. Therefore, this rejection is not being made final. Note that the new grounds of rejection for claims 1 and 11 are necessitated by Applicant’s amendments of those claims.
Applicant has argued that di Iorio et al do not teach independent removal of the substack from the stack as now required by amended claims 1 and 11. However, a plain reading of paragraphs [0131]-[0139], especially paragraph [0136], shows that di Iorio et al clearly contemplated removal of a single module (i.e. substack) without removal of the other modules.
Claim Rejections - 35 USC § 112
The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
Claims 1-4, 7, 9, 11-14, 19, and 21 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. Independent claims 1 and 11 have been amended to recite:
“wherein an exterior surface of the cathode unipolar plate is configured to removably abut an exterior surface of an anode unipolar plate of an adjacent substack, and/or
wherein an exterior surface of the anode unipolar plate is configured to removably abut an exterior surface of an anode unipolar plate of an adjacent substack.” (emphasis added)
The specification as filed shows that cathode unipolar plate of one substack abutting the anode unipolar plate of an adjacent substack. The specification does not teach the anode unipolar plate of one substack abutting the anode unipolar plate of the adjacent substack.
The Office assumes that this error was likely due to a typographic mistake as opposed to intentional oversight by Applicant. Therefore, for the remainder of this action, the Office will assume that the second wherein clause quoted above recites that “an exterior surface of the anode unipolar plate is configured to removably abut an exterior surface of a[[n]] cathode unipolar plate of an adjacent substack” (emphasis added to highlight difference).
Claim Rejections - 35 USC § 103
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 1-3, 7, 9, 11-13, 19, 21, 23-25, and 27-28 are rejected under 35 U.S.C. 103 as being unpatentable over di Iorio et al (US 2022/00582353 A1) in view of Henderson et al (US 2006/0099480 A1) and Vulliez et al (WO 2023/285751 A1, with reference to US 2024/0339646 A1 as an English translation thereof, citations below refer to US document).
Regarding claim 1, di Iorio et al teach (see abstract, figs. 1, 2, and 5, paragraphs [0088]-[0101]) a stack of electrolysis cells made from a plurality of substacks of electrolysis cells, each substack (M1, M2, M3) comprising a plurality of electrochemical cells, an anode unipolar plate (e.g. 3.1, 3.2, 3.3), a cathode unipolar plate (e.g. 4.1, 4.2, 4.3), wherein the plurality of electrochemical cells are positioned between and enclosed by the anode unipolar plate and the cathode unipolar plate (see e.g. fig. 5). Di Iorio et al teach (see paragraphs [0118]-[0119]) that the substack was configured to be independently added to the stack as a single unit. Di Iorio et al further teach (see paragraph [0131]) that a defective substack was independently removable without replacement of other modules, according to the procedure set forth in paragraphs [0132]-[0139].
Di Iorio et al fail to teach (1) that each of the plurality of electrochemical cells included a cathode flow field, an anode flow field, and a membrane positioned therebetween and (2) that the exterior surface of the cathode unipolar plate was configured to removably abut an exterior surface of an anode unipolar plate of an adjacent substack.
Regarding (1), note that di Iorio et al do teach (see paragraph [0088]) that each cell included an anode, electrolyte (i.e. membrane) and cathode, but does not explicitly disclose the cells including flow fields.
Henderson et al teach (see abstract, figs. 1-5) a stack (200) of electrolysis cells, wherein each individual cell included a cathode flow field (260 on side 255 of bipolar plate 210), an anode flow field (250 on side 245 of bipolar plate 210), and a membrane (205) positioned therebetween. The cell architecture of Henderson et al permitted (see paragraphs [0002], [0006]-[0010]) the electrolysis cell stack to be operated at sustained high pressures while offering a low profile (i.e. low cell thickness) configuration.
Therefore, it would have been obvious to one of ordinary skill in the art at the time of filing to have incorporated the cathode flow field/membrane/anode flow field cell architecture taught by Henderson et al in the substack of di Iorio et al to permit operation at sustained high pressures with cells having a small thickness (thereby allowing a higher cell density per unit volume).
When the teachings of di Iorio et al and Henderson et al were combined by one of ordinary skill in the art, a first anode flow field (250 on side 245 of bipolar plate 210 of Henderson et al) would have been positioned adjacent to the anode unipolar plate of di Iorio et al and a second cathode flow field (260 on side 255 of bipolar plate 210 of Henderson et al) would have been positioned adjacent to the cathode unipolar plate of di Iorio et al. Henderson et al show (see figs. 3-5) the cathode flow field of a first cell being positioned on one face of the bipolar plate and adjacent to the anode flow field of an adjacent, second cell on the opposing face of the bipolar plate.
Regarding (2), note that di Iorio et al teach the presence of seals (6.1, 6.2) and electrical contact members (5.1, 5.2) between adjacent substacks, such that the exterior surfaces of adjacent substacks do not abut one another.
In the same field of endeavor of creating electrolysis stacks using substacks, Vulliez et al teach (see abstract, figs. 1 and 2, paragraphs [0085]-[0090]) a substack (M1, M2, M3) for an electrochemical stack, the substack comprising: a plurality of electrochemical cells; an anode unipolar plate (stiffening plate P1); and a cathode unipolar plate (stiffening plate P2) such that the plurality of electrochemical cells were positioned between and enclosed by the anode unipolar plate and the cathode unipolar plate (see fig. 2). The substack is configured to be independently added to the electrochemical stack. Vulliez et al teach that the exterior surfaces of facing unipolar plates of adjacent substacks abutted one another without intervening structures. The stiffening plates (i.e. the unipolar plates as claimed) ensured (see paragraph [0085]) electrical connection with the (sub)stacks located above and below and the fluidic connection.
Therefore, it would have been obvious to one of ordinary skill in the art at the time of filing to have modified the substacks of di Iorio et al according to the suggestion of Vulliez et al by configuring the unipolar plates directly abut the unipolar plate of the adjacent substack while ensuring electrical and fluid connections. One of ordinary skill in the art at the time of filing would have recognized that the lack of intervening structures between adjacent substacks would have reduced complexity of assembly of the substacks together into a stack.
Regarding claims 2 and 3, Henderson et al teach bipolar plates at each of the interfaces between the anode flow field of one cell and the cathode flow field of the adjacent cell.
Regarding claim 7, with respect to the claim limitation “wherein the substack is configured to be independently tested or examined for one or more performance parameters prior to addition to the electrochemical stack”, Applicant is reminded that apparatus claims are distinguished by their structural elements and that while claims may recite functional elements, the claim only requires the structure implicitly required by the functional limitations. Here, the claimed functional limitation does not impart any structural limitations on the substack. See MPEP 2114. A review of the instant specification and drawings does not reveal any structure which allows the function of the substack being capable of being tested, and thus the functional limitation fails to further limit the structure. Never the less, di Iorio et al teach (see paragraphs [0105]-[0114]) that assembled substacks were subjected to testing of one or more performance parameters, such that the substacks of di Iorio et al are considered to inherently be configured as claimed. Di Iorio et al teach (see paragraphs [0105]-[0114]) that the parameters tested include hydrostatic leaks (“test of leaktightness”) and cell isolation (“total electrical voltage of each module is then measured, which makes it possible to validate the correct electrical functioning of each module”).
Regarding claim 9, Henderson et al teach (see paragraph [0023]) operating the electrolysis stack at current densities of 50-4000 Amps per square foot (0.05-4.3 Amps per square centimeter) with a per cell voltage of 1.48-3.0 volts. One of ordinary skill in the art would have expected the pure resistive loss to inherently be less than 200 mV when the voltage was 1.48 V, due to the inherent overvoltages present for the anode catalyst and cathode catalyst.
Regarding claim 11, Di Iorio et al as modified by Henderson et al and Vulliez et al teach a stack having a plurality of substacks, where each substack included the claimed structure set forth in claim 1. See rejection grounds above. Di Iorio et al further teach (see paragraph [0051]) that the stack also included two additional end plates that included fluid junctions with the surrounding fluid management system. These end plates constitute “manifolds” as set forth in claim 11. Vulliez et al teach (see fig. 1, paragraph [0086]) providing end plates in a manner similar to the end plates taught by di Iorio et al. The end plates of Vulliez et al are about the adjacent unipolar plate of the outermost substacks (i.e. PE1 abuts P2 of substack M1 and PE2 abuts P1 of substack M3).
Regarding claims 12 and 13, Henderson et al teach bipolar plates at each of the interfaces between the anode flow field of one cell and the cathode flow field of the adjacent cell.
Regarding claim 19, as noted with respect to claim 11 above, the specification fails to define any structure which makes the substack capable of being tested, such that the limitation “configured to be tested or examined” fails to impart additional structural elements. See MPEP 2114. Nevertheless, di Iorio et al teach (see paragraphs [0105]-[0114]) that assembled substacks were subjected to testing of one or more performance parameters, such that the substacks of di Iorio et al are considered to inherently be configured as claimed.
Regarding claim 21, Henderson et al teach (see paragraph [0023]) operating the electrolysis stack at current densities of 50-4000 Amps per square foot (0.05-4.3 Amps per square centimeter) with a per cell voltage of 1.48-3.0 volts. One of ordinary skill in the art would have expected the pure resistive loss to inherently be less than 200 mV when the voltage was 1.48 V, due to the inherent overvoltages present for the anode catalyst and cathode catalyst.
Regarding claim 23, di Iorio et al teach (see abstract, figs. 1, 2, and 5, paragraphs [0088]-[0101], [0105]-[0121]) a method of forming a stack of electrolysis cells comprising forming a plurality of substacks (M1, M2, M3), each substack comprising a plurality of electrochemical cells, an anode unipolar plate (e.g. 4.1, 4.2, 4.3), a cathode unipolar plate (e.g. 3.1, 3.2, 3.3), wherein the plurality of electrochemical cells are positioned between the anode unipolar plate and the cathode unipolar plate, testing each substack for one or more performance parameters (leak test, electrical voltage test), and inserting and aligning (“positioning”) the substacks. Although di Iorio et al fail to expressly teach a step of identifying substacks that achieve a threshold test result for the one or more performance parameters , the only purpose for testing the substacks in the method of di Iorio et al would be to correctly identify acceptable substacks and unacceptable substacks, and to have only used the acceptable substacks for forming the stack such that the step is clearly obvious to one of ordinary skill in the art. Di Iorio et al teach (see paragraphs [0118]-[0120]) that the substack was configured to be added to the stack as a single unit.
Di Iorio et al fail to teach (1) that each of the plurality of electrochemical cells included a cathode flow field, an anode flow field, and a membrane positioned therebetween, and (2)
Regarding (1), note that di Iorio et al do teach (see paragraph [0088]) that each cell included an anode, electrolyte (i.e. membrane) and cathode, but does not explicitly disclose the cells including flow fields.
Henderson et al teach (see abstract, figs. 1-5) a stack (200) of electrolysis cells, wherein each individual cell included a cathode flow field (260 on side 255 of bipolar plate 210), an anode flow field (250 on side 245 of bipolar plate 210), and a membrane (205) positioned therebetween. The cell architecture of Henderson et al permitted (see paragraphs [0002], [0006]-[0010]) the electrolysis cell stack to be operated at sustained high pressures while offering a low profile (i.e. low cell thickness) configuration.
Therefore, it would have been obvious to one of ordinary skill in the art at the time of filing to have incorporated the cathode flow field/membrane/anode flow field cell architecture taught by Henderson et al in the substack of di Iorio et al to permit operation at sustained high pressures with cells having a small thickness (thereby allowing more cell density per unit volume).
When the teachings of di Iorio et al and Henderson et al were combined by one of ordinary skill in the art, a first anode flow field (250 on side 245 of bipolar plate 210 of Henderson et al) would have been positioned adjacent to the anode unipolar plate of di Iorio et al and a second cathode flow field (260 on side 255 of bipolar plate 210 of Henderson et al) would have been positioned adjacent to the cathode unipolar plate of di Iorio et al. Henderson et al show (see figs. 3-5) the cathode flow field of a first cell being positioned on one face of the bipolar plate and adjacent to the anode flow field of an adjacent, second cell on the opposing face of the bipolar plate. Additionally, the anode unipolar plate of a first substack (e.g. 4.1) would have abutted against the first terminal plate and the cathode unipolar plate of a last substack (e.g. 4.3) would have abutted against the second terminal plate.
Regarding (2), note that di Iorio et al teach the presence of seals (6.1, 6.2) and electrical contact members (5.1, 5.2) between adjacent substacks, such that the exterior surfaces of adjacent substacks do not abut one another.
In the same field of endeavor of creating electrolysis stacks using substacks, Vulliez et al teach (see abstract, figs. 1 and 2, paragraphs [0085]-[0090]) a substack (M1, M2, M3) for an electrochemical stack, the substack comprising: a plurality of electrochemical cells; an anode unipolar plate (stiffening plate P1); and a cathode unipolar plate (stiffening plate P2) such that the plurality of electrochemical cells were positioned between and enclosed by the anode unipolar plate and the cathode unipolar plate (see fig. 2). The substack is configured to be independently added to the electrochemical stack. Vulliez et al teach that the exterior surfaces of facing unipolar plates of adjacent substacks abutted one another without intervening structures. The stiffening plates (i.e. the unipolar plates as claimed) ensured (see paragraph [0085]) electrical connection with the (sub)stacks located above and below and the fluidic connection.
Therefore, it would have been obvious to one of ordinary skill in the art at the time of filing to have modified the substacks of di Iorio et al according to the suggestion of Vulliez et al by configuring the unipolar plates to directly abut the unipolar plate of the adjacent substack while ensuring electrical and fluid connections. One of ordinary skill in the art at the time of filing would have recognized that the lack of intervening structures between adjacent substacks would have reduced complexity of assembly of the substacks together into a stack.
Regarding claim 24, di Iorio et al discuss (see paragraphs [0131]-[0139]) that disassembly of the stack could be conducted to replace a “defective module”. A “defective module” cannot be determined absent the performance of at least one test of at least one performance parameter. Thus, although no recitation of testing the entire stack is mentioned by di Iorio et al, such step inherently occurs to identify a “defective module”.
Regarding claim 25, di Iorio et al teach the testing being for cell leaks (i.e. “hydrostatic leaks”).
Regarding claim 27, di Iorio et al teach (see fig. 2, paragraphs [0106]-[0107]) providing a first unipolar plate (e.g. 4.1), adding the layers of the cells adjacent to the first unipolar plate, the layers of the cells comprising a first bipolar plate, the membrane electrode assembly and an additional bipolar plate, and finishing with providing a second unipolar plate (e.g. 3.1) to complete the substack.
Regarding claim 28, the act of checking for leaks in the assembled substacks inherently results in a reduction in misalignment of the cell stack since misalignments of cell layers may result in leaks. Further, by the inherent step of rejecting any substack that does not pass the leak test, there is an inherent reduction in misalignment in the final stack when compared to a fully assembled stack not produced using substacks.
Claims 4 and 14 are rejected under 35 U.S.C. 103 as being unpatentable over di Iorio et al (US 2022/0052353 A1) in view of Henderson et al (US 2006/0099480 A1) and Vulliez et al (WO 2023/285751 A1) as applied to claims 1 or 11, respectively, above, and further in view of Shiepe et al (US 2006/0286429 A1).
Henderson et al teach (see figs. 10-14, paragraph [0046]) the presence of a porous gas diffusion layer (420) between the one side of the membrane and the adjacent flow field (250).
Henderson et al fail to teach a porous transport layer being positioned between the anode flow field and the membrane or that the gas diffusion layer was positioned between the cathode flow field and the membrane.
Shiepe et al teach (see fig. 2, paragraphs [0020]-[0024]. [0030]), in an electrolysis cell stack, providing porous flow members between both sides of a membrane and the adjacent bipolar plates, wherein the porous flow members enhanced the flow of fluids to and from the electrode surfaces of the cell.
Therefore, it would have been obvious to one of ordinary skill in the art at the time of filing to have utilized porous flow members as taught by Shiepe et al adjacent to both the anode side of the membrane and the cathode side of the membrane of Henderson et al to improve the fluid flow to and from both electrode surfaces of the membrane as taught by Shiepe et al. Note that there is no structural difference between a gas diffusion layer and a porous transport layer as claimed.
Conclusion
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/HARRY D WILKINS III/Primary Examiner, Art Unit 1794
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