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 Amendment
Claims 1-8, 10-11, 13-14, 16, 19, 21-22, 57, 61, and 65 remain pending in the application with claims 9, 12, 15, 17-18, 20, 23-56, 58-60, 62-64, and 65-67 canceled and claim 68 newly canceled. Applicant’s amendments to the Specification and Claims have overcome every claim objection rejection previously set forth in the Final Office Action mailed 11/4/2025. The examiner missed prosecuting claim 68 in the Final Office Action, of which the limitations have been added to claim 1, and updated the rejection for claim 65. This action is therefore made Non-Final.
Response to Arguments
Applicant's arguments filed 1/6/2026 have been fully considered but they are not persuasive.
The applicant submits on pages 10-11 of Remarks submitted 1/6/2026, that switch S1 is not part of any switch network, because the switch S1 cannot "selectively couple the energy storage element (transformer T1) to different ones of the cells in the battery pack." Instead (as the Examiner states in the first paragraph of page 4 of the Office Action) the switch S1 couples the primary winding of the transformer T1 to the whole of the cell stack M1.
Further, as accepted by the Examiner, there is no disclosure or suggestion in Kunimitsu that the switches S10 - S19 are controlled by a PWM signal (see Page 3, lines 7 - 8 of the Office Action), and thus it cannot be said that the "operation of the switch network [of switches S10 - S19] is synchronised to the clock signal" in Kunimitsu.
Only the switch S1 is controlled by a PWM control signal. Thus, even if the PWM control signal could be regarded as a clock signal, only the operation of the switch S1 could possibly be said to be synchronised to the clock signal. But the switch S1 is not part of any "switch network comprising a plurality of switches for selectively coupling the energy storage element to different ones of the cells in the battery pack," as explained above.
The examiner submits that all energy transfer between cells is routed appropriately through switches S10-S19 (¶[21]) and all energy transfer occurs by passing through transformer T1 and S1. Therefore, PWM applied to S1 is applied to the energy transfer between cells E1-E5 (Fig. 1 and ¶[19]) even though the PWM is not applied directly to the switches S10-S19.
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.
Claims 1-7, 16, 21, 57, and 65 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Kunimitsu (US 20210083331 A1, published 2021-03-18).
Regarding independent claim 1, Kunimitsu teaches a circuitry for balancing cells in a battery pack (Fig. 1), the circuitry comprising:
a cell balancing circuitry (Fig. 1: 10, 20, 30, 40) configured to transfer energy (¶0032) between cells of the battery pack (Fig. 1: E1-E20) in synchronization with a clock signal (¶’s [30, 19] and Fig. 1: pulse width modulation operates on periodic on/off cycles comparable to a clock signal. "First power source circuit 12 steps down the voltage across first power storage module M1 to charge one of the plurality of cells E1 to E5." When compared to Fig. 1, this means that the voltages across M1[i.e. E1-E5] is input to the primary side of transformer 12 by closing switch S1. When the selected switches on the secondary side lead to a cell, that means energy has been transferred between cells); and
a control circuitry (Fig. 1: controlling circuit 50) configured to control a parameter of the clock signal (¶0030) based on a monitored parameter (¶0029: OCV/SOC) or information associated with the battery pack;
wherein the cell balancing circuitry comprises:
an energy storage element (Fig. 1 and ¶[30, 19]: inductors in transformer T1 in power source circuit 12); and
a switch network comprising a plurality of switches for selectively coupling the energy storage element to different ones of the cells in the battery pack (Fig. 1: S10-19);
wherein operation of the switch network is synchronized to the clock signal (¶’s [30, 19] and Fig. 1: pulse width modulation operates on periodic on/off cycles comparable to a clock signal. "First power source circuit 12 steps down the voltage across first power storage module M1 to charge one of the plurality of cells E1 to E5." When compared to Fig. 1, this means that the voltages across M1[i.e. E1-E5] is input to the primary side of transformer 12 by closing switch S1. When the selected switches on the secondary side lead to a cell, that means energy has been transferred between cells).
Regarding claim 2, Kunimitsu teaches the circuitry according to claim 1, further comprising voltage monitor circuitry for monitoring a voltage of the cells of the battery pack (¶0029).
Regarding claim 3, Kunimitsu teaches the circuitry according to claim 2, wherein the monitored parameter associated with the battery pack comprises one or more of:
a voltage of the battery pack (¶0029);
a voltage difference between a first cell and a second cell of the battery pack; a difference between a voltage a first cell of the battery pack having a highest voltage or state of charge and a voltage of a second cell of the battery pack having a lowest voltage of state of charge; an impedance of a cell of the battery pack; and a statistical measure related to the voltage of the battery pack of the voltage of one or more cells of the battery pack (limitations above are listed in alternative form).
Regarding claim 4, Kunimitsu teaches the circuitry according to claim 1, further comprising current monitor circuitry for monitoring a load current of the battery pack (¶0030: “charging current flows in accordance [with] the voltage of the cell, and the amount of the charging current can be adjusted by performing the PWM control on first switch S1”).
Regarding claim 5, Kunimitsu teaches the circuitry according to claim 4, wherein the monitored parameter associated with the battery pack comprises one of more of: an instantaneous load current (¶0030); and an average load current over a predetermined period of time (limitation is listed in alternative form).
Regarding claim 6, Kunimitsu teaches the circuitry according to claim 1, wherein the monitored parameter associated with the battery pack comprises one of more of: an inferred instantaneous load current (¶0030); and an inferred average load current over a predetermined period of time.
Regarding claim 7, Kunimitsu teaches the circuitry according to claim 6, wherein the control circuitry (¶0027 controlling circuit 50) is configured to infer the instantaneous load current (¶0030: “charging current flows in accordance [with] the voltage of the cell”) and/or the average load current based on a measured voltage of one or more cells of the battery pack.
Regarding claim 16, Kunimitsu teaches the circuitry according to claim 1, wherein the parameter of the clock signal comprises a frequency of the clock signal or a duty cycle of the clock signal (¶0030: a key component of pulse width modulation is duty cycle).
Regarding claim 21, Kunimitsu teaches the circuitry according to claim 1, wherein the cell balancing circuitry comprises: a switch network (Fig. 1: S10-19, S21-25, S31-35, S41-45); and an inductor (transformers T1-4);
wherein the switch network is controllable such that:
in a first phase of operation of the cell balancing circuitry, the inductor is coupled in parallel with a cell of a first module of the battery pack; and
in a second phase of operation of the cell balancing circuitry, the inductor is coupled in parallel with a different cell of the first module or with a cell of a second module of the battery pack.
(¶0030: The examiner interprets the first phase as when the transformer receives energy from a charged cell and the second phase as when the target cell to be charged receives energy from the transformer)
Regarding independent claim 57, Kunimitsu teaches an integrated circuit comprising control circuitry for use in the circuitry of claim 1 (See rejection for claim 1).
Regarding independent claim 65, Kunimitsu teaches a controller (¶0027 controlling circuit 50) for outputting a clock signal ((¶’s [30, 19] and Fig. 1: pulse width modulation operates on periodic on/off cycles comparable to a clock signal. "First power source circuit 12 steps down the voltage across first power storage module M1 to charge one of the plurality of cells E1 to E5." When compared to Fig. 1, this means that the voltages across M1[i.e. E1-E5] is input to the primary side of transformer 12 by closing switch S1. When the selected switches on the secondary side lead to a cell, that means energy has been transferred between cells) for controlling a switching frequency of switches for selectively coupling an energy storage element to cells of a battery in circuitry for balancing the cells in the battery (¶ [27,34]: active balancing is performed through the balancing switches S10 to S19), wherein the controller is controlled based on a monitored parameter of, or information associated with, the battery (¶[27]: control circuit 50 acquires OCV of cells E1 to E5 and specifies the cell having the lowest OCV).
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.
Claim 8 is rejected under 35 U.S.C. 103 as being unpatentable over Kunimitsu in view of Pressas et al. (US 20190293723 A1, published 2019-09-26).
Regarding claim 8, Kunimitsu teaches the circuitry according to claim 1, wherein the control circuitry (¶0027 controlling circuit 50) is configured
to monitor an impedance of a cell of the battery pack (¶0026: internal resistance of each cell is estimated), and
Kunimitsu does not teach the control circuitry configured
to cause the cell balancing circuitry not to apply charging current to the cell during a cycle of the cell balancing circuitry if the impedance of the cell is below a predetermined threshold and/or adjust an impedance of a switch of the cell balancing circuitry based on the impedance of the cell.
Pressas teaches a control circuitry configured
to cause the cell balancing circuitry to adjust an impedance of a switch of the cell balancing circuitry based on the impedance of the cell (¶0035).
Both Kunimitsu and Pressas teach battery charging systems. It would have been obvious to a person with ordinary skill in the art before the effective filing date to incorporate the adjusting of a switch based on the impedance of a cell to safely charge or discharge the battery (¶0007).
Claims 10-11 and 13-14 are rejected under 35 U.S.C. 103 as being unpatentable over Kunimitsu in view of Cattin et al. (US 20140315047 A1, published 2014-10-23).
Regarding claim 10, Kunimitsu teaches the circuitry according to claim 1, wherein the control circuitry is configured
to infer an impedance of cells of the battery pack based on current that flows through switches of the cell balancing circuitry (¶0026: “The internal resistance can be estimated by dividing a voltage drop, generated when a predetermined current is allowed to pass through the battery for a predetermined time”), and
Kunimitsu does not teach the control circuitry configured to determine an electrical model of the battery pack based at least in part on the inferred impedances.
Cattin teaches control circuitry configured to determining an electrical model of the battery pack based at least in part on the inferred impedances (¶0016,0032).
Both Kunimitsu and Cattin teach battery systems. It would have been obvious to a person with ordinary skill in the art before the effective filing date to incorporate the control circuitry determining an electrical model of a battery in the system of Cattin into the system of Kunimitsu to accurately assess the aging of the battery (¶0013).
Regarding claim 11, Kunimitsu in view of Cattin teaches the circuitry according to claim 10, wherein Cattin further teaches the control circuitry is configured to control or modulate a parameter of the clock signal based on the electrical model of the battery pack; and/or adjust an impedance of a switch of the cell balancing circuitry based on the electrical model of the battery pack (¶0040: frequency determined from impedance of battery to be charged).
Regarding claim 13, Kunimitsu teaches the circuitry according to claim 1.
Kunimitsu does not teach the circuitry wherein the information associated with the battery pack comprises information from a system, external to the circuitry, belonging to a host device that incorporates the circuitry.
Cattin teaches circuitry wherein the information associated with the battery pack comprises information from a system, external to the circuitry, belonging to a host device that incorporates the circuitry (¶0159: information may be downloaded from a remote server).
Kunimitsu and Cattin both teach battery systems. It would have been obvious to a person with ordinary skill in the art before the effective filing date to incorporate the remote server from Cattin into the system of Kunimitsu to easily update information in the system.
Regarding claim 14, Kunimitsu in view of Cattin teaches the circuitry according to claim 13, wherein Kunimitsu teaches the clock signal is generated or received by the control circuitry (¶0030).
Claims 19 and 22 are rejected under 35 U.S.C. 103 as being unpatentable over Kunimitsu in view of Morita (US 20040246635 A1, published 2004-12-09).
Regarding claim 19, Kunimitsu teaches the circuitry according to claim 18, wherein the cell balancing circuitry comprises: a switch network (Fig. 1: S10-19, S21-25, S31-35, S41-45).
Kunimitsu does not teach the cell balancing circuitry comprises a capacitor, and
wherein the switch network is controllable such that:
in a first phase of operation of the cell balancing circuitry, the capacitor is coupled in parallel with a cell of a first module of the battery pack; and
in a second phase of operation of the cell balancing circuitry, the capacitor is coupled in parallel with a different cell of the first module or with a cell of a second module of the battery pack.
Morita teaches the cell balancing circuitry comprises a capacitor, and
wherein the switch network is controllable such that:
in a first phase of operation of the cell balancing circuitry, the capacitor is coupled in parallel with a cell of a first module of the battery pack (Fig. 5 has structure capable of performing the balancing process as described in ¶0015 and Fig. 1 where a first cell is coupled to a capacitor); and
in a second phase of operation of the cell balancing circuitry, the capacitor is coupled in parallel with a different cell of the first module or with a cell of a second module of the battery pack (¶0015: in the second phase the capacitor is couple to a second cell adjacent to the first cell).
Both Kunimitsu and Morita teach circuitry for cell balancing. It would have been obvious to a person with ordinary skill in the art before the effective filing date to incorporate the capacitors in the circuitry of Morita into the circuitry of Kunimitsu for simpler circuit design and saving on manufacturing costs.
Regarding claim 22, Kunimitsu teaches the circuitry according to claim 1.
Kunimitsu does not teach wherein the cell balancing circuitry comprises: a switch network; and a set of capacitors coupled in parallel between the switch network and a common node;
wherein the switch network is controllable such that:
during a first phase of operation of the cell balancing circuitry the set of capacitors is coupled to a first portion of a first plurality of cells of the battery pack; and
during a second phase of operation of the cell balancing circuitry the set of capacitors is coupled to a second portion of the first plurality of cells and to a first portion of a second plurality of cells of the battery pack, wherein the first and second portions of the first plurality of cells comprise at least one different cell of the first plurality of cells.
Morita teaches cell balancing circuitry (Fig. 5: voltage detection circuit 60) comprising: a switch network (61-66); and a set of capacitors (67-69) coupled in parallel between the switch network and a common node (connecting node N4);
wherein the switch network is controllable (Fig. 5: control section 39) such that:
during a first phase of operation of the cell balancing circuitry the set of capacitors (67-69) is coupled to a first portion of a first plurality of cells of the battery pack (B1-B2); (Fig. 5 has structure capable of performing the balancing process as described in ¶0015 and Fig. 1) and
during a second phase of operation of the cell balancing circuitry the set of capacitors (67-69) is coupled to a second portion of the first plurality of cells and to a first portion of a second plurality of cells of the battery pack (B2-B3), wherein the first and second portions of the first plurality of cells comprise at least one different cell of the first plurality of cells.
(The examiner interprets first and second portions of the first plurality of cells as B1 and B2 respectively, and the first portion of the second plurality of cells as B3)
Both Kunimitsu and Morita teach circuitry for cell balancing. It would have been obvious to a person with ordinary skill in the art before the effective filing date to incorporate the capacitors in the circuitry of Morita into the circuitry of Kunimitsu for simpler circuit design and saving on manufacturing costs.
Claim 61 is rejected under 35 U.S.C. 103 as being unpatentable over Kunimitsu in view of Lin (US 20140097787 A1, published 2014-04-10).
Regarding independent claim 61, Kunimitsu teaches a host device comprising the circuitry of claim 1 (See rejection for claim 1).
Kunimitsu does not teach wherein the host device comprises an electric vehicle, an electric bicycle, an electric scooter, a cordless power tool, a computing device, a laptop, netbook, notebook or tablet computer, a portable battery powered device, a mobile telephone or an accessory device for such a host device.
Lin discloses a host device (¶0006: electric vehicle) comprising of balancing circuitry (battery management system).
Both Lin and Kunimitsu disclose circuits for balancing batteries. It would have been obvious to a person with ordinary skill in the art before the effective filing date to substitute the circuitry of Kunimitsu in an EV as suggested by Lin for the purpose of balancing cells in an EV.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Kim teaches a cell balancing circuitry (Fig. 18) configured to transfer energy between cells of the battery pack in synchronisation with a clock signal (¶0070: pulse width modulation (PWM) is used for energy transfer between cells); and
a control circuitry configured to control a parameter of the clock signal based on a monitored parameter or information associated with the battery pack (¶’s [31, 70]: Control of PWM is for the purpose of balancing a monitored voltage of cells in the battery pack).
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Ryu-Sung Peter Weinmann whose telephone number is (703)756-5964. The examiner can normally be reached Monday-Friday 9am-5pm ET.
Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Julian Huffman, can be reached at (571) 272-2147. The fax phone number for the organization where this application or proceeding is assigned is (571) 273-8300.
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/Ryu-Sung P. Weinmann/Examiner, Art Unit 2859 January 21, 2026
/JULIAN D HUFFMAN/Supervisory Patent Examiner, Art Unit 2859