DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application is being examined under the pre-AIA first to invent provisions.
Response to Arguments
Applicant has amended independent claims 1, 9, and 10. Claim 2 has been canceled without prejudice.
Applicant argues that the prior art of record, Maegawa et al (US 20120086406 A1) modified by Xu et al (US 20210143661 A1), does not teach the amended feature “constant-current charging the battery with a second charge current
I
2
from the second voltage
U
2
to a third voltage
U
3
” asserting that “the amended claim requires a specific charging sequence in which the later constant current charging steps are performed in relation to the second voltage
U
2
and the third voltage
U
3
”.
Regarding Maegawa, applicant asserts “Maegawa’s alternating charging process does not disclose the claimed successive constant current charging from the second voltage
U
2
to the third voltage
U
3
using the second charge current
I
2
”. Maegawa FIG 4, particularly between timings T5 and T10, depicts the claimed constant current/constant voltage charging process. A constant current if I6 is applied between timings T5 and T6 until the terminal voltage reaches V3, at which point the constant voltage of V3 is applied to charging the battery. That constant voltage of V3 is applied between timings T6 and T7 until current I5 is reached, at which point the constant current of I5 is applied to charging the battery. That constant current of I5 is applied between timings T7 and T8 until the voltage of V4 is reached, at which point the constant voltage of V4 is applied to charging the battery. That constant voltage of V4 is applied between timing T8 and T9 until the current of I2 is reached, at which point the current of I2 is applied to charging the battery. That constant current of I2 is applied between timing T9 and T10 until the voltage of Vf is reached, thereby disclosing the same charging process as that claimed in the present application.
Applicant's arguments filed 07/30/2026 have been fully considered but they are not persuasive.
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(s) 1, 6, and 9-10 is/are rejected under 35 U.S.C. 103 as being unpatentable over Maegawa et al (US 20120086406 A1) modified by Nishino et al (US 20100188048 A1).
Regarding claim 1, Maegawa teaches a method for charging a battery, wherein the method comprises: constant-current charging the battery with a first charge current I₁ to a first voltage U₁ (FIG 4 CC1, ¶0056 "[FIG 3] the charging current corresponding to the current value I1 is supplied from the charger 35 to the secondary battery 4 in response to the control by the controller 37, whereby constant current charge CC1 is executed (step S3)", ¶0057 "[FIG 3] When the terminal voltage Vb is less than the threshold voltage value Vth (NO in step S4), the charge controller 501 repeats step S3 to continue with the constant current charge CC1")
and constant-voltage charging the battery with the first voltage U₁ to a first charge cut-off current I₁’; (FIG 4 CV1, ¶0058 "the charging voltage corresponding to the voltage value V1 is supplied from the charger 35 to the secondary battery 4 in response to the control by the controller 37, whereby constant voltage charge CV1 is executed (step S5)", ¶0061 "[FIG 3] When the charging current value Ic becomes equal to or lower than the threshold current value Ith (YES in step S6, at the timing T3), the charge controller 501 proceeds to step S7")
constant-current charging the battery with the first charge current I₁ to a second voltage U₂, wherein U₂ is a limited charge voltage of the battery, and U₂ > U₁; (FIG 4 timing T6 to T7, ¶0067 “charge controller 501 then executes steps S3 to S7 again with the set current value Is as the current value I6… charging current is taken as the current value I6 and constant voltage charge CV3 (at timings T6 to T7) where the charging voltage is taken as the voltage value V3”)
and constant-current charging the battery with a second charge current I₂ from the second voltage U₂ to a third voltage U₃ (FIG 4 timing T7 to T8, ¶0071 “charge controller 501 executes steps S3 to S7 again with the set current value Is as the current value I5, the threshold voltage value Vth as the voltage value V4, and the threshold current value Ith as the current value 12, so as to execute the constant current charge CC4 (at timings T7 and T8)”)
and constant-voltage charging the battery with the third voltage U₃ to a second charge cut-off current
I
2
'
, wherein
U
3
>
U
2
,
I
2
<
I
1
, and
I
1
'
≤
I
2
'
; (FIG 4 timing T8 to T9, ¶0071 “charging current is taken as the current value I5 and the constant voltage charge CV4 (at timings T8 and T9) where the charging voltage is taken as the voltage value V4”, ¶0072 “charging current value Ic becomes equal to or lower than the threshold current value Ith (YES in step S6, at the timing T9) during the constant voltage charge CV4 (at the timings T8 and T9), the charge controller 501 proceeds to step S7”)
[wherein the method further comprises determining the first voltage U₁, and the step of determining the first voltage U₁ comprises: determining a phase change potential Vc of a cathode material in the battery;]
[obtaining a state of charge of the battery at the phase change potential and determining a corresponding anode potential Vₐ;]
and obtaining a voltage
U
c
v
of the battery based on the phase change potential Vc and the anode potential Vₐ, wherein
U
c
v
=
V
c
-
V
a
, and
U
1
=
U
c
v
. (¶0038 "charge controller 201... When the terminal voltage Vb of the secondary battery 4 detected by the voltage detector 51 reaches a predetermined threshold voltage value Vth, the charge controller 501 uses the communication units 53, 36 to transmit the request instruction on the charging voltage equivalent to the threshold voltage value Vth, to the controller 37")
Phase change potential measures the voltage across the battery terminals at which the lithium- ions begin to precipitate, thereby being a measure of the internal resistance of the battery. Maeagawa does not teach determining the first voltage U1, and the step of determining the first voltage U1 comprises: determining a phase change potential Vc of a cathode material in the battery; obtaining a state of charge of the battery at the phase change potential and determining a corresponding anode potential Va.
Maegawa does not teach wherein the method further comprises determining the first voltage U₁, and the step of determining the first voltage U₁ comprises: determining a phase change potential Vc of a cathode material in the battery; obtaining a state of charge of the battery at the phase change potential and determining a corresponding anode potential Vₐ.
Nishino teaches wherein the method further comprises determining the first voltage U₁, and the step of determining the first voltage U₁ comprises: determining a phase change potential Vc of a cathode material in the battery; (¶0135 "terminal voltage .alpha.1 across the secondary battery 141 having the highest terminal voltage rises and reaches the set voltage Vs first. Then, deposited lithium is deposited and grown on the negative electrode plate 303 in the secondary battery 141 and reaches the positive electrode plate 301")
obtaining a state of charge of the battery at the phase change potential and determining a corresponding anode potential Vₐ. (¶0130 " In association with an increase of the state of charge .gamma.1, differences among the terminal voltages .alpha.1, .alpha.2, and .alpha.3 increase gradually", 135 "The negative electrode plate 303 and the positive electrode 301 are thus short-circuited. In this manner, when the terminal voltage .alpha.1 reaches the set voltage Vs, deposited lithium is formed and broken repetitively. The terminal voltage .alpha.1 is thus maintained at the set voltage Vs")
Therefor it would be obvious to one of ordinary skill in the art, before the effective filing date, to modify the method as taught by Maegawa wherein the method further comprises determining the first voltage U₁, and the step of determining the first voltage U₁ comprises: determining a phase change potential Vc of a cathode material in the battery; obtaining a state of charge of the battery at the phase change potential and determining a corresponding anode potential Vₐ as taught by Nishino. Maeagawa discloses a charging method using multiple constant current and constant voltage phases to charge a battery across battery terminals. Nishino similarly discloses a charging method using a constant current phase and a constant voltage phase, including measuring the difference in potential between the anode and cathode. The modification would be obvious because one of ordinary skill in the art would be motivated to prevent an internal short-circuit caused by deposited lithium, thereby minimizing battery degradation and prolonging battery lifespan.
Similarly for claim 9 as applied to an electronic apparatus, wherein the electronic apparatus comprises: a battery; (Maegawa ¶0016 "charging system 1 is a battery-equipped device system", Maegawa ¶0017 "battery pack 2 has a secondary battery 4, a charge control circuit 5, a current detection resistor 6, switching elements Q1, Q2, and connecting terminals 11, 12, 13")
and a processor configured to execute a charging method. (Maegawa ¶0036 "controller 50 is constituted by, for example, a CPU (Central Processing Unit) for executing a predetermined arithmetic process", Maegawa ¶0037 "controller 50 functions as a charge controller 501 by executing the control program stored in the ROM")
Similarly for claim 10 as applied to a storage medium storing at least one computer instruction, wherein the instruction is loaded by a processor, configured to execute a charging method. (Maegawa ¶0036 "controller 50 is constituted by, for example, a CPU (Central Processing Unit) for executing a predetermined arithmetic process", Maegawa ¶0037 "controller 50 functions as a charge controller 501 by executing the control program stored in the ROM")
Regarding claim 6, Maegawa modified by Nishino teaches the method according to claim 1. Maegawa FIG 4 illustrates the charging process, including a first charging current I6 applied between timings T5 and T6 and a second charging current I5 applied between timings T7 and T8. The second charging current I5 is less than the first charging current I6; however, Maegawa modified by Nishino does not explicitly disclose wherein 0.51₁ < I₂ <
I
1
.
Applicant specification ¶0049 discloses "It is necessary to consider the second charge current I.sub.2 and an overcharge voltage comprehensively to ensure that when the second charge current I.sub.2 is used for overvoltage charge, no lithium precipitation occurs at the anode and no over delithiation occurs at the cathode of the battery. Therefore, the second charge current needs to satisfy 0.51.sub.1<l.sub.2<l.sub.1" asserting that the second current must be between 0.5
I
1
and
I
1
.
Maegawa as modified by Nishino discloses the claimed invention except for 0.51₁ < 1₂ <
I
1
; it would have been an obvious matter of design choice to use 0.51₁ < l₂ < 11, since applicant has not disclosed that this current range solves any stated problem or is for any particular purpose and it appears that the invention would perform equally well with an I2 which is simply smaller than I1 as taught by Xu. The modification would be obvious because one of ordinary skill in the art would be motivated to minimize the overcharge voltage and improve the lifespan and overall performance of the battery.
Claim(s) 3-5 is/are rejected under 35 U.S.C. 103 as being unpatentable over Maegawa modified by Nishino and further in view of Inoue et al (US 20210126290 A1)
Regarding claim 3, Maegawa modified by Nishino teaches the method according to claim 1. Maegawa modified by Nishino further teaches wherein the method further comprises determining the first charge current I₁, and the step of determining the first charge current I₁ comprises: after the battery has been discharged to a fully discharged state, charging the battery with a first preset current [at a preset temperature] to a fully charged state; (Maegawa ¶0061 "[FIG 3] charge controller 501 proceeds to step S7. The charge controller 501 then compares the threshold current value Ith with the current value If (step S7). In the timing T3, the threshold current value Ith is set at the current value 10 in place of the current value If (NO in step S7). Thus, the charge controller 501 proceeds to step S1 to repeat the subsequent constant current constant voltage charge again")
[discharging the battery with a second preset current to the fully discharged state;]
[after cyclically performing the charging the battery with the first preset current to the fully charged state and discharging the battery with the second preset current to the fully discharged state for a preset number of times, determining whether lithium precipitation occurs on an anode plate of the battery;]
and [if lithium precipitation occurs on the anode plate of the battery,] determining that the first preset current is the first charge current I₁ of the battery [at the preset temperature.] (Maegawa ¶0056 "controller 37 the request instruction requesting for the charging current corresponding to the current value I1. Accordingly, the charging current corresponding to the current value I1 is supplied from the charger 35 to the secondary battery 4 in response to the control by the controller 37, whereby constant current charge CC1 is executed (step S3)")
Maeagawa modified by Nishino does not teach discharging the battery with a second preset current to the fully discharged state; after cyclically performing the charging the battery with the first preset current to the fully charged state and discharging the battery with the second preset current to the fully discharged state for a preset number of times, determining whether lithium precipitation occurs on an anode plate of the battery; and if lithium precipitation occurs on the anode plate of the battery, [determining that the first preset current is the first charge current
I
1
of the battery] at the preset temperature.
Inoue teaches discharging the battery with a second preset current to the fully discharged state; (¶0209 "Discharging was performed until the battery 1 was fully discharged by constant-current discharging")
after cyclically performing the charging the battery with the first preset current to the fully charged state and discharging the battery with the second preset current to the fully discharged state for a preset number of times, (¶0198 "FIG. 11 is a graph illustrating the measurement results, the horizontal axis representing the number of cycles, and the vertical axis representing the discharge capacity (mAh)")
determining whether lithium precipitation occurs on an anode plate of the battery; (¶0155 "Each charged battery was maintained at 60° C. for 14 days, and the positive electrode mixture molded body was taken out from the battery to measure the thickness")
and if lithium precipitation occurs on the anode plate of the battery, [determining that the first preset current is the first charge current
I
1
of the battery] at the preset temperature. (¶0155 "Each charged battery was maintained at 60° C. for 14 days, and the positive electrode mixture molded body was taken out from the battery to measure the thickness", ¶0206 "controller 24 controls a charging current to be supplied to the battery 1 by adjusting a drive voltage of the FET 21")
Therefor it would be obvious to one of ordinary skill in the art, before the effective filing date, to modify the method as taught by Maeagawa modified by Nishino to discharge the battery with a second preset current to the fully discharged state and after cyclically performing the charging the battery with the first preset current to the fully charged state and discharging the battery with the second preset current to the fully discharged state for a preset number of times, determining whether lithium precipitation occurs on an anode plate of the battery as taught by Inoue. Maeagawa modified by Nishino discloses a method of alternating between phases of constant current and constant voltage to fast-charge a rechargeable battery to full using controller 37. Similarly Inoue teaches a method of charging and discharging a rechargeable battery using phases of constant current and constant voltage to improve battery capacity. Inoue FIG 11 discloses a decline in discharge capacity over a number of charge/discharge cycles, the decline in discharge capacity is necessarily caused by lithium precipitation inside of the battery cell. It would be obvious to incorporate the method of constant current discharge at a maintained temperature as taught by Inoue into the method of controller 37 as taught by Maeagawa modified by Nishino. The modification would be obvious because one of ordinary skill in the art would be motivated to improve battery performance across multiple duty cycles.
Regarding claim 4, Maegawa modified by Nishino and Inoue teaches the method according to claim 3. Maegawa modified by Nishino and Inoue further teaches wherein the step of determining the first charge current
I
1
further comprises: if no lithium precipitation occurs on the anode plate of the battery, adjusting the first preset current; (Maegawa ¶0075 "charge controller 501 executes steps S3 to S7 again with the set current value Is as the current value 12, the threshold voltage value Vth as the voltage value Vf", Inoue ¶0155 "Each charged battery was maintained at 60° C. for 14 days, and the positive electrode mixture molded body was taken out from the battery to measure the thickness"; Inoue measures the thickness produced including if no thickness is added during a charge cycle and then controller as taught by Maegawa as modified by Nishino would adjust the current in response)
charging the battery with the adjusted first preset current at the preset temperature to the fully charged state; (Maegawa ¶0056 "controller 37 the request instruction requesting for the charging current corresponding to the current value I1", Inoue ¶0155 "Each charged battery was maintained at 60° C. for 14 days, and the positive electrode mixture molded body was taken out from the battery to measure the thickness", Inoue ¶0206 "controller 24 controls a charging current to be supplied to the battery 1 by adjusting a drive voltage of the FET 21")
discharging the battery with the second preset current to the fully discharged state; (Inoue, ¶0209 "Discharging was performed until the battery 1 was fully discharged by constant-current discharging", Maegawa ¶0075 "charge controller 501 executes steps S3 to S7 again with the set current value Is as the current value 12, the threshold voltage value Vth as the voltage value Vf, and the threshold current value Ith as the current value")
after cyclically performing the charging the battery with the adjusted first preset current to the fully charged state and discharging the battery with the second preset current to the fully discharged state for a preset number of times, determining whether lithium precipitation occurs on the anode plate of the battery; (Inoue ¶0198 "FIG. 11 is a graph illustrating the measurement results, the horizontal axis representing the number of cycles, and the vertical axis representing the discharge capacity (mAh)", Inoue ¶0155 "Each charged battery was maintained at 60° C. for 14 days, and the positive electrode mixture molded body was taken out from the battery to measure the thickness")
and if lithium precipitation occurs on the anode plate of the battery, determining that the adjusted first preset current is the first charge current I₁ of the battery at the preset temperature. (Inoue ¶0155 "Each charged battery was maintained at 60° C. for 14 days, and the positive electrode mixture molded body was taken out from the battery to measure the thickness", Maegawa ¶0056 "controller 37 the request instruction requesting for the charging current corresponding to the current value I1")
Regarding claim 5, Maegawa modified by Nishino teaches the method according to claim 1. Maegawa modified by Nishino does not teach wherein U₂ < U₃ ≤ U₂ + 500mV.
Inoue teaches wherein U₂ < U₃ ≤ U₂ + 500mV. (¶0127 "a constant voltage that slightly fluctuates within a range of regular variation from 1.746 to 1.854 V is supplied to the battery")
Maeagawa as modified by Nishino discloses the claimed invention except for wherein U₂ < U₃ ≤ U₂ +500mV. It would have been obvious to one having ordinary skill in the art at the time the invention was made to maintain the constant voltage phase within a small range such as U₂ < U₃ ≤ U₂ + 500mV, since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. Therefor it would be obvious to one of ordinary skill in the art, before the effective filing date, to modify the method as taught by Maeagawa as modified by Nishino wherein U₂ < U₃ ≤ U₂ + 500mV as taught by Inoue. The modification would be obvious because one of ordinary skill in the art would be motivated to improve battery performance across multiple duty cycles.
Claim(s) 7 and 8 is/are rejected under 35 U.S.C. 103 as being unpatentable over Maegawa modified by Nishino and further in view of Dang et al (US 20190237974 A1).
Regarding claim 7, Maegawa modified by Nishino teaches the method according to claim 1. Maegawa modified by Nishino does not teach wherein
0.1
C
<
I
1
'
<
0.6
C
, C being a charge/discharge rate.
Dang teaches wherein
0.1
C
<
I
1
'
<
0.6
C
, C being a charge/discharge rate. (¶0037 "a C-rate of 0.2C means that the current to charge the battery has a magnitude of 240 mA")
Therefor it would be obvious to one of ordinary skill in the art, before the effective filing date, to further modify the method as taught by Maeagawa modified by Nishino wherein 0.1C < I₁ < 0.6C, C being a charge/discharge rate as taught by Dang. Maeagawa as modified by Nishino discloses a method and charging circuit for charging a battery using alternating current phase and voltage phases, similarly Dang discloses a method and system for charging a battery using constant current and constant voltage phases. The modification would be obvious because one of ordinary skill in the art would be motivated to reduce the strain on the power infrastructure and the battery resulting in improved battery longevity.
Regarding claim 8, Maegawa modified by Nishino and Dang teaches the method according to claim 7. Maegawa modified by Nishino and Dang further teaches wherein
0.1
C
<
I
2
'
<
0.6
C
. (¶0037 "a C-rate of 0.2C means that the current to charge the battery has a magnitude of 240 mA")
Maeagawa as modified by Xu discloses a method of alternating constant current and constant voltage charging phases using a first current
I
1
and a second current
I
2
, ensuring a low c-rate minimizes the internal resistance due to lithium precipitate forming.
Prior Art Not Relied Upon
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure can be found in the attached PTO-892 Notice of References Cited by Examiner attached to this correspondence.
Jung et al (US 20150077058 A1) discloses a method of charging a battery which uses multiple constant current constant voltage charging phases separated by idle periods. Each constant current charging period is applied until a predetermined voltage is reached, and then that voltage is applied until a predetermined current is reached.
Chen et al (US 20200235601 A1) discloses a method of charging a battery using a constant current constant voltage charging pattern which repeats over k stages until the battery reaches fully charged.
Conclusion
THIS ACTION IS MADE FINAL. 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 LISA M KOTOWSKI whose telephone number is (571)270-3771. The examiner can normally be reached Monday-Friday 8a-5p.
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) 2722147. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/LISA KOTOWSKI/Examiner, Art Unit 2859
/JULIAN D HUFFMAN/Supervisory Patent Examiner, Art Unit 2859
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