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 .
Drawings
The drawings were received on 7 August 2026. These drawings are acceptable.
Response to Amendment
The amendment filed on 7 August 2026 has been entered. Claims 1-4 remain pending in the application. Applicant’s amendments to the drawings have overcome the objections previously set forth in the Non-Final Office Action mailed on 27 May 2026. All previous prior art grounds of rejection are withdrawn as necessitated by the amendments to the claims. New grounds of rejection are presented herein.
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention.
Claim 1 is rejected under 35 U.S.C. 102(a)(1) as being anticipated by Niroumand et al. (WO 2022/099409 A1).
Regarding claim 1, Niroumand teaches a method for testing an electrochemical stack made of a plurality of cells, which may be a fuel cell or electrolyzer stack (p. 5, [0010]; Fig. 6, [0080]). The stack comprises an anode, or hydrogen electrode (Fig. 6, one of the electrodes within 610a-d; [0080]); a cathode, or oxygen electrode (Fig. 6, the other electrode within 610a-d; [0080]); a hydrogen storage tank (640) and oxygen-containing gas storage tank (650, [0081]); a hydrogen supply channel (line connecting H2 tank 640 to anode inlet 620); and an oxygen supply flow path (line connecting Ox tank 650 to cathode inlet 630).
When the stack is activated, hydrogen is supplied to the hydrogen electrode, and oxygen or air is supplied to the oxygen electrode (pp. 26-27, [0041]: of a fuel cell, with identical underlying structure; see also p. 35, [0059], relevance further explained herein). These gases are supplied to the hydrogen and oxygen electrode chambers before any electrolysis reaction is started (Abstract: “prior to break-in or operation of the stack.”). Niroumand further teaches the claimed method of measuring the open circuit voltage of the cell stack and comparing the measurement to a threshold value to determine if an abnormality exists (p. 5, [0010]: comparing voltage to a reference voltage to determine presence of defects).
The methods disclosed generally reference fuel cells but are taught to be applicable to all electrochemical stacks, including electrolyzer stacks (p. 35, [0059]; p. 4, [0008]).
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 2-4 are rejected under 35 U.S.C. 103 as being unpatentable over Niroumand et al. (WO 2022/099409 A1) in view of Takami et al. (JP 2021-105194 A, as previously attached).
Regarding claim 2, Niroumand does not teach that pure water is circulated through the oxygen electrode after the open circuit voltage of the water electrolysis stack is measured. However, Takami teaches another electrochemical device for the generation of hydrogen by water electrolysis (p. 28, [0002]) including a stack of multiple electrolytic cells (p. 36, [0037]). Takami further teaches circulating pure water through the oxygen electrode at a time after measuring the open circuit voltage ([0108], [0112]: as ultrapure water, after shutdown procedure). Although not specifically disclosed as open circuit voltage, the voltage measurement is taken when no current is applied and is thus equivalent ([0023]). The addition of pure water to the oxygen electrode permits a short-term recovery electrolysis process, reducing degradation of the electrode ([0113]-[0115]).
It would have been obvious to one of ordinary skill in the art before the effective filing date to circulate pure water through the oxygen electrode of Niroumand after the OCV measurement. One of ordinary skill in the art would have done so in order to reduce degradation of the oxygen electrode as taught by Takami.
Regarding claims 3 and 4, Niroumand further teaches embodiments of claim 1 including a cell stack (Niroumand pp. 45-47, [0088]-[0089]: electrolyzer in some embodiments; fig. 7, (705)), a control unit (720), and a voltage sensor to measure the open circuit voltage (710). The control unit necessarily stores the threshold value, as it is configured to control operation of the cell voltage monitoring system (p. 46, [0089]). The control system communicates with a gas supply subsystem (730) responsible for circulating hydrogen and oxygen through their respective electrodes (p. 46, [0088]). The control system is capable of carrying out the previously taught process of determining if an abnormality exists in the water electrolysis stack through open circuit voltage measurement and comparison to a threshold or reference value, as the art of record has been applied to claims 1 and 2.
The circulation of pure water through the electrode as taught by Takami and applied to claim 2 above occurs after stopping the electrolysis operation (Takami p. 56, [0112]: as ultrapure water, after shutdown procedure). After the voltage drops to less than a threshold value of 0.8 V, current is applied to the stack again, resulting in an electrolysis reaction and therefore circulation of oxygen through the electrode (p. 56, [0114]: “potential recovery electrolysis” ). The open circuit voltage of the stack is measured during this procedure (p. 56, [0113]: as potentials when electrolysis is stopped). This procedure of circulating water through the electrode after shutdown is within the ability of the previously taught control unit, as Takami also teaches a control system (p. 35, [0033]) with a control device (10) equipped with a voltage sensor (38). The control unit is also able to circulate hydrogen and oxygen through the stack (p. 36, [0036]).
Response to Arguments
Applicant's arguments filed 7 August 2026 have been fully considered but they are not persuasive. The remarks on p. 8 argue that Niroumand does not teach the amended claimed combination of a hydrogen storage tank, oxygen-containing gas storage tank, etc. The Examiner respectfully disagrees as the recited structure is taught in Niroumand Fig. 6 as cited herein, and the capabilities are taught in combination with Takami as cited.
In response to the remarks on p. 9 that Takami does not teach determining an abnormality based on open circuit voltage, this teaching is provided by Niroumand in the passages cited herein in the rejections made under 35 U.S.C. § 103. Takami teaches providing pure water to the electrode after measurement of open circuit voltage. As claims 2-4 have been amended, they do not require pure water be circulated through the oxygen electrode after determination of an abnormality; but more broadly, after OCV is measured.
Applicant’s arguments with respect to claims 1-4 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.
Consequently, for at least these reasons, the Examiner finds the Applicant’s arguments unpersuasive.
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.
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/CBF/Examiner, Art Unit 1711
/MICHAEL E BARR/Supervisory Patent Examiner, Art Unit 1711
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