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 .
This office action addresses pending claims 1-6. Claims 1 and 6 were amended in the response field 1/30/2026.
Information Disclosure Statement
The information disclosure statement (IDS) submitted on 5/19/2026 was filed after the mailing date of the non-final office action on 10/1/2025. The submission is in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement is being considered by the examiner.
Claim Objections
Claim 2 is objected to because of the following informalities: “temperature acquired” in line 2 should be changed to “coolant temperature acquired” for consistency with the independent claim. Appropriate correction is required.
Claims 4-6 are objected to because of the following informalities: “when the temperature decreases” in lines 1-2 should be changed to “when the coolant temperature decreases” for consistency with the independent claim. Appropriate correction is required.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claim(s) 1-2, 4, and 6 is/are rejected under 35 U.S.C. 103 as being unpatentable over Norimoto (JP 2013/171682, see Applicant supplied machine translation) in view of Watanabe et al. (US 2010/0141262) and Koyama et al. (JP 2018-181688, see Applicant supplied machine translation).
Regarding claim 1, Norimoto discloses a fuel cell system comprising a fuel cell 2, a cell voltage detector 2c that detects voltage of each one or each group of unit cells, a temperature detector 2d that detects temperature of the fuel cell 2 (temperature acquisition unit), and a control device 6 that limits output of the fuel cell 2 in a case where the temperature is equal to or higher than a predetermined temperature and fluctuation velocity of the voltage has to be equal to or lower than a predetermined threshold for a fixed time period (abstract).
The fuel cell generates electric power by an electrochemical reaction between a fuel gas and an oxygenizing gas ([0002]). A current sensor 2a and a voltage sensor 2b for detecting a current and voltage output from the fuel cells 2 are attached to the fuel cells 2 ([0022]).
The control device 6 includes a CPU and various memories, that receives input of signals supplied from various sensor, and controls the output voltage and output current of the fuel cell 2 (controls a generated current indicative of a power generation amount of the fuel cell stack) ([0033]).
The control device 6 determines whether or not the temperature input from the temperature sensors 2d is equal to or higher than a predetermined temperature T1, as a predetermined temperature T1 is set to a temperature at which dry-up may occur in the fuel cell ([0040]-[0041]). The control device 6 limits the outputs of the fuel cell 2 when the temperature if the fuel cell is higher than a predetermined threshold, and when a fluctuation rate of voltage is equal to or lower than a predetermined value for a predetermined time t1 ([0046]). Further, Norimoto teaches that a predetermined time has elapsed (step S3) is used in determining when to limit output ([0045], Fig 3).
However, while Norimoto teaches a current sensor and voltage sensor (and therefore equipment that can determine the resistance), Norimoto does not explicitly disclose a resistance acquisition unit configured to acquire an electrical resistance value of the fuel cell stack, nor wherein the limiting of power generation amount is also determined by the electrical resistance value being higher than a resistance threshold.
Watanabe discloses a method of utilizing the resistance of the membrane as a method for detecting abnormality occurring in the fuel cell (abstract). A criterion for judging a deterioration in performance of a fuel cell based on the resistance of an electrolytic membrane is thereby set higher as the electrolytic membrane approaches a dry state (abstract). The fuel cell system includes a sensor group 300 that includes a current sensor 310, a FC temperature sensor 320, an air flow meter 330, a gas pressure sensor 340, and a humidification amount sensor 350 ([0060]). Further, an impedance measure module 220 measures the electric current and voltage of the fuel cells 100 ([0085]); and therefore the system must include a voltage sensor.
The performance degradation is based on evaluation of the ohmic resistance of the fuel cell (therefore having resistance acquisition unit) ([0012]-[0013]). If the calculated ohmic resistance Rohm is greater than the reference value (degradation reference value Rref), then the detection unit 400 controls an alarm unit 500 ([0090], step S114 of Fig 5). The detection unit 400 includes a CPU 410 that performs a diversity of processes, computations, determinations, and controls, a memory 420 that stores degradation detection criteria tables 422, an input interface 430, and an output interface 440 that transmits alarm instructions ([0061]). The detection unit 400 calculates the ohmic resistance ([0086]). Watanabe further teaches that the resistance increases as the temperature or moisture content decreases (i.e., dry state), and that the resistance decreases as the temperature or moisture content increases (i.e., wet state) (abstract).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to either replace the fluctuation velocity of voltage {for evaluating whether the fuel cell is operating normally, [0044]} with or combine the determining and using the fuel cell ohmic resistance greater than a reference value to determine degradation (and dry state) as taught by Watanabe with the method of limiting a fuel cell system to prevent drying in Norimoto for the purpose of easily judging whether the fuel cell is deteriorated/dry (Watanabe, abstract).
However, while Norimoto discloses using a fuel cell temperature ([0040]-[0041]), modified Norimoto does not explicitly disclose using a coolant temperature, and the temperature set according to a drying boundary line in a temperature threshold map including the generated current and the coolant temperature, and limiting by setting the generated current to a target generated current for which the temperature threshold is below the drying line and which includes a margin to avoid hunting of the process.
Koyama discloses a fuel cell system which can contribute to generation efficiency (abstract). A control device of the fuel cell system stores a program and a control map related to a determination of dryness ([0042]). The dryness determination is performed with reference to the cooling water temperature [coolant temperature] and output of the fuel cells 1 ([0049]). It is determined that the fuel cell is in a dry state [higher than a temperature threshold] when the coolant temperature is higher than the determination reference value associated with the power value of the fuel cells on the dry determination control map ([0050], see Fig 3).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to combine the control map of cooling water temperature and output of fuel cells for determining dryness of Koyama with the method of preventing drying in Norimoto for the purpose of contribution to generation efficiency.
In addition, because Norimoto teaches limiting output ([0045]) and teaches controlling the output current of the fuel cell ([0033]), it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to perform the process of limiting power generation by setting the generated current [lower] to a temperature threshold below the drying boundary line.
In addition, because Norimoto recognizes that fluctuations and hunting occurs ([0044]), it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to correct to a margin to avoid hunting of the process.
Regarding claim 2, modified Norimoto discloses all of the claim limitations as set forth above. While Norimoto teaches that a duration of time is taken into consideration before limiting the output ([0039]) and that a predetermined time is used for the fluctuation rate voltage determination in order to account for the fuel cell recovering without doing anything ([0045]), modified Norimoto does not explicitly disclose wherein the power generation amount is limited if the temperature acquired by the temperature acquisition unit remains higher than the temperature threshold for a first predetermined time period, and thereafter the electrical resistance value remains higher than the resistance threshold for a second predetermined time period. That is, Norimoto does not explicitly disclose using a first and/or second predetermined time in conjunction with temperature acquire and electrical resistance value.
However, because Norimoto teaches using a predetermined time in order to account for the fuel cell recovering without doing anything ([0045]), it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to use a first and/or second predetermined time period for the temperature and electrical resistance thresholds of modified Norimoto for the purpose of determining and potentially allowing for the fuel cell to recover on its own without doing anything (Norimoto, [0045]).
Regarding claims 4 and 6¸modified Norimoto discloses all of the claim limitations as set forth above. Norimoto teaches that when the temperature is not greater than the threshold temperature (step S1: No), that there is no limitation on power generation, even if other factors are outside their respective threshold (see Fig 3, and step S1: No, which does not lead to limiting the power generation, and instead loops). Therefore, the limitation of power generation is canceled even if the electrical resistance value is higher than the resistance threshold.
Claim(s) 3 and 5 is/are rejected under 35 U.S.C. 103 as being unpatentable over Norimoto (JP 2013/171682, see Applicant supplied machine translation) in view of Watanabe et al. (US 2010/0141262) and Koyama et al. (JP 2018-181688, see Applicant supplied machine translation), as applied to claim 1 above, and further in view of Aoki et al. (US 2017/0045588) and Imanishi et al. (US 2016/0141690).
Regarding claim 3, modified Norimoto discloses all of the claim limitations as set forth above. Norimoto teaches that the temperature threshold is determined in advance ([0041]), and Watanabe teaches that the temperature influences the resistance of the electrolyte membrane ([0078]-[0080], Fig 4). Therefore, the combination discloses an average processing value of a power generation amounts within a set time as Norimoto teaches using a predetermined value and uses a values within a fixed time period (abstract).
However, modified Norimoto does not explicitly disclose using a low pass filter processing value of power generation amounts, and the temperature threshold is set to a higher value as the processed power generation amount is larger.
Aoki discloses an impedance measuring device that output an alternating current (abstract). The impedance measuring devices includes a first and second detection unit ([0007]). The detector circuits include an in-phase extraction unit 710 ([0091]-[0092]) that comprises an in-phase low-pass filter 712 ([0091]-[0094]). The in-phase low-pass filter 712 smooths the in-phase alternating-current signal ([0096]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to combine the low-pass filter of the impedance measuring unit of Aoki with the sensors of Norimoto modified by Watanabe for the purpose of smoothing out the signal. Therefore, the combination further teaches a low pass filter processing value.
Imanishi teaches an object to suppress drying of a fuel cell using an impedance detector, and a current limit that is configured to limit an output current of the fuel cell with a limiting rate (abstract). The impedance Z of the fuel cell is received (step S310), a temperature T is received (step S320), and a limiting map is referred to in order to compute the current limiting amount (step S330) (Fig 3). As seen in Figure 5, a current limiting map MP is present with fuel cell temperature, current limiting rate, and several different impedance calculations (Za, Zb, Zc, Zd). That is, Imanishi teaches using multiple calculations to determine the appropriate amount of current limiting.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to combine the current limiting map with multiple calculations as taught by Imanishi with the output limiting of the fuel cell of Norimoto for the purpose of determining an appropriate amount of limiting.
Regarding claim 5¸ modified Norimoto discloses all of the claim limitations as set forth above. Norimoto teaches that when the temperature is not greater than the threshold temperature (step S1: No), that there is no limitation on power generation, even if other factors are outside their respective threshold (see Fig 3, and step S1: No, which does not lead to limiting the power generation, and instead loops). Therefore, the limitation of power generation is canceled even if the electrical resistance value is higher than the resistance threshold.
Response to Arguments
Applicant's arguments filed 1/30/2026 have been fully considered but they are not persuasive.
Applicant argues that the Examiner has not provided a convincing or persuasive reason why it would be appropriate to combine the references in the manner suggested by the Examiner, and even if the references are combined, the combination fails to produced application’s invention as claimed. Applicant specifically argues the references do not disclose the amended limitations (arguments at page 8).
This is not considered persuasive. With regards to the previous rejection, the Examiner provided a rationale from the prior art for the combination. Applicant has not provided any argument as to why the combination is not convincing or persuasive.
With regards to the new amended limitations, a new reference, Koyama et al. (JP 2018-181688) already of record and provided by applicant, is relied upon to address said new amended limitations. See the above rejection for details.
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 JACOB BUCHANAN whose telephone number is (571)270-1186. The examiner can normally be reached M-F 8:00-5:00 PM (ET).
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Nicole Buie-Hatcher can be reached at 571-270-3879. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/JACOB BUCHANAN/ Examiner, Art Unit 1725
/NICOLE M. BUIE-HATCHER/ Supervisory Patent Examiner, Art Unit 1725
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