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 .
Status of the Claims
In the communication filed on 06/17/2026 claims 1-3 and 5 are pending. Independent claim 1 has been completely rewritten. Furthermore, claim 1 incorporates portions of cancelled claim 4 and has introduced the new limitation “saturation state” not previously presented. Claim 5 has been amended to correct claim objections raised in the Office Action dated 03/19/2026.
Response to Arguments/Amendments
Applicant’s arguments with respect to claim 1 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.
Specifically, the applicant argues in pages 7-10 of the Remarks dated 06/17/2026 that the prior art references do not teach the limitations “the discharge operation comprising turning ON all the switches such that the plurality of batteries respectively discharge through the balance resistors to decrease the voltages of the batteries in a saturation state”. The examiner concurs however a newly found prior art is cited for teaching these limitations as presented below.
The remaining arguments are moot as the applicant’s arguments for the remaining claims were based on dependency of the independent claims.
The drawing objection is withdrawn due to the amendments made.
The claim objections are withdrawn; however, new claim objections are made below necessitated by the amendments.
This Office Action is made Final due to the amendments.
Claim Objections
Claim 1 is objected to because of the following informalities: in line 14 remove the division symbol “÷” after “wherein” to improve reading comprehension. For examination purposes below this limitation will be interpreted as “wherein”, however, appropriate correction is required. In line 21 add --plurality of-- in front of “batteries” in order to avoid a lack of antecedent basis issue. For examination purposes below this limitation will be interpreted as “the plurality of batteries”, however, appropriate correction is required.
Claim 5 is objected to because of the following informalities: in lines 4 and 9 replace “corresponding” with --plurality of-- in order to avoid a lack of antecedent basis issue. For examination purposes below this limitation will be interpreted as “the plurality of batteries”, however, appropriate correction is required. In line 8 remove “turned-ON” and add --that were turned ON--after switches in order to avoid a lack of antecedent basis. For examination purposes this limitation will be interpreted as “the switches that were turned-ON”, however, appropriate correction is required.
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1, 3, and 5 are rejected under 35 U.S.C. 103 as being unpatentable over Zhang et al. (USPGPN 20250141238), in view of Yoshida (WIPO Patent WO-2016098631-A1), and further in view of White et al. (USPGPN 20090289599).
With respect to claim 1, Zhang teaches a battery life extension method (¶[75]; a mode of operation is taught wherein prolongs the life of the battery pack), comprising acts of continuously detecting a voltage of each of a plurality of batteries after a battery pack consisting of the plurality of batteries connected in series is determined to have been fully charged and set in a stationary state (Figs. 2-11; the monitoring unit 118 detects in real-time the individual voltages of the series-connected batteries 150 in the battery pack, see ¶ [283]. In ¶ [54] by monitoring the voltages of the series-connected batteries it may be determined that the battery pack has been fully charged in which one of ordinary skill understands would set the battery pack into a stationary state).
Zhang teaches setting a first difference from a difference between a highest voltage and a lowest voltage among the plurality of batteries (¶[213]; a first difference between the maximum voltage value and the minimum voltage value among the plurality of batteries is determined).
Zhang teaches setting a second difference from a difference between the voltage of each of the plurality of batteries and the lowest voltage (¶[220]; a second difference between the actual voltage of each of the plurality of batteries and the minimum voltage value is determined).
Zhang teaches wherein each of the plurality of batteries is connected in parallel with a balance resistor through a switch (¶[222]; each battery core is connected in parallel to a bleeder unit comprising a switch and a resistor).
Zhang teaches performing a balance operation until every second difference is smaller than a second predetermined voltage difference or until the lowest voltage is smaller than a balance starting voltage when the first difference is greater than the first predetermined voltage difference and the lowest voltage is greater than the balance starting voltage are determined (¶[220-221]; teaches when the voltage difference between the highest and lowest battery cells (i.e., first difference) is above a preset threshold, and the lowest voltage is still above a minimum level, a balancing operation is started and continues until all the voltage differences between each cell and the lowest voltage (i.e., second differences) fall below a smaller preset value).
Zhang teaches the second predetermined voltage difference is smaller than the first predetermined voltage difference (¶[220-221]; a second preset difference is 30 mV and a third preset difference is 10 mV. It is understood by one of ordinary skill a first preset difference would be larger since the first difference is between the max cell voltage – min cell voltage, the second difference is between each cell voltage – min voltage, and the third difference is between the target cell voltage – min voltage thus first preset > second preset > third preset).
However, Zhang fails to explicitly teach performing a discharge operation until the lowest voltage is smaller than a discharge starting voltage when the first difference is smaller than a first predetermined voltage difference and the lowest voltage is greater than the discharge starting voltage are determined, the discharge operation comprising turning ON all the switches such that the plurality of batteries respectively discharge through the balance resistors to decrease the voltages of the batteries in a saturation state; and the discharge starting voltage is greater than the balance starting voltage.
Yoshida teaches performing a discharge operation until the lowest voltage is smaller than a discharge starting voltage when the first difference is smaller than a first predetermined voltage difference and the lowest voltage is greater than the discharge starting voltage are determined (In Figs. 2-3 a discharging operation is performed until the balance operation conditions are met in step S110 when the maximum voltage and minimum voltage difference is greater than a difference threshold in step S202 and when the minimum voltage among the battery cells is below a predetermined reference voltage VB).
While Yoshida initiates discharging when the voltage difference is large and the minimum cell voltage is already low approaching the discharge end voltage, it would have been obvious for one of ordinary skill to have modified the battery pack of Zhang with the discharging operation of Yoshida to initiate discharging when the minimum voltage is still above the cutoff voltage. The benefit of this modification being extending the battery life thereby decreasing operational and maintenance (O&M) costs.
While Yoshida teaches initiating discharging when the minimum voltage approaches a low reference threshold and Zhang teaches balancing based on preset voltage differences, it would have been obvious to one of ordinary skill to set a discharge starting voltage greater than the balance starting voltage when combining the teachings. The benefit to this modification being to clearly distinguish when to perform a discharging operation versus when to start a balance operation thereby providing a logical way to manage battery safety and efficiency depending on the imbalance.
However, Zhang fails to explicitly teach the discharge operation comprising turning ON all the switches such that the plurality of batteries respectively discharge through the balance resistors to decrease the voltages of the batteries in a saturation state.
White teaches the discharge operation comprising turning ON all the switches such that the plurality of batteries respectively discharge through the balance resistors to decrease the voltages of the batteries in a saturation state (¶[66-67]; all of the battery cells are partially discharged via the shunt resistors (26a, 26b) of the balancing circuit (25a, 25b) when the system has a high SOC (i.e., in a saturation state) thus it is understood that the voltage of the batteries is reduced).
A fully charged battery left for a long time in a high-voltage saturation state will age faster. Thus, it would have been obvious to one of ordinary skill in the art prior to the effective filing date to have adapted White’s partial discharge when the battery is over-charge with a high-SOC to Zhang’s balancing system in order to reduce the strain on the over-charged battery system. The advantage of this being the system could automatically and independently attain a balanced state of charge without damaging equipment (see ¶[20-21] of White).
With respect to claim 3, Zhang teaches the invention as discussed above in claim 1. Further, Zhang teaches further comprising an act of terminating the discharge operation or the balance operation if the battery pack is determined in charging or in discharging during the discharge operation or the balance operation (In ¶ [213-214, 218] teach terminating a discharge or balance operation when charging or discharging is detected when fault conditions including voltage imbalance are detected).
With respect to claim 5, Zhang teaches the invention as discussed above in claim 1. Further, Zhang teaches wherein the balance operation comprises turning ON the switches connected in parallel with the corresponding batteries having second differences greater than the first predetermined voltage difference to discharge through the balance resistors, and continuously detecting whether each of the second differences is smaller than the second predetermined voltage difference; and turning OFF all the turned-ON switches connected in parallel with the corresponding batteries when the second difference of any of the plurality of batteries is smaller than the second predetermined voltage difference (¶[221-222]; teach that each battery core is connected in parallel with a bleeder resistor and switch, and during balancing, the control module identifies the target battery cores (i.e., those with voltages exceeding the second preset difference from the minimum), turns on their respective bleeder switches to discharge them, and continuously detects voltages to determine when to stop discharging by turning off the switches when voltage difference fall below the present threshold).
Claim 2 is rejected under 35 U.S.C. 103 as being unpatentable over Zhang in view of Yoshida and White, and further in view of Wang et al. (USPGPN 20200049772).
With respect to claim 2, Zhang teaches the invention as discussed above in claim 1. However, Zhang fails to explicitly teach wherein the determination of the battery pack consisted of the plurality of batteries that has been fully charged and set in the stationary state comprises a holding time period of a total voltage or an average voltage of the battery pack that has been fully charged and set in the stationary state is greater than a determined time period.
Wang teaches wherein the determination of the battery pack consisted of the plurality of batteries that has been fully charged and set in the stationary state comprises a holding time period of a total voltage or an average voltage of the battery pack that has been fully charged and set in the stationary state is greater than a determined time period (In ¶ [22, 26, and 41] teach determining when a battery pack has reached a stationary state after charging by requiring the voltage to stabilize over a sufficient holding period).
Therefore, it would have been obvious for one of ordinary skill to have modified the battery pack of Zhang with the relaxation time (i.e., stationary state) determination method of Wang in order to require a total or average value to remain above a threshold for a sufficient holding time period. The advantage to this modification being that open circuit voltage used for estimation is accurate thereby improving battery life management and preventing error due to making estimates based on a sufficiently relaxed cell voltage (see ¶ [45] of Wang).
Relevant Prior Art
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
The additional prior art identified by the applicant in the Information Disclosure Statement (IDS) were considered by the examiner, however, for examination purposes were not relied upon for citation purposes.
Ro (USPGPN 20110193525) teaches a balancing circuit comprising a resistor in series with a switch both in parallel with a battery cell.
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 Frank A Silva whose telephone number is (703)756-1698. The examiner can normally be reached Monday - Friday 09:30 am -06:30 pm ET.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Drew Dunn can be reached at 571-272-2312. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/FRANK ALEXIS SILVA/Examiner, Art Unit 2859
/DREW A DUNN/Supervisory Patent Examiner, Art Unit 2859
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