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
In response to the amendment received August 26, 2026:
Claims 1 and 4-15 are pending. Claims 2-3 have been cancelled as per applicant’s request.
The core of the previous rejection is maintained with slight changes made in light of the amendment. All changes to the rejection are necessitated by the amendment.
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.
Claims 1 and 4-14 are rejected under 35 U.S.C. 103 as being unpatentable over Koo et al. (EP 3609000A1) in view of Kitano et al. (EP 3252193A), both cited in the Information Disclosure Statement received October 29, 2025.
Regarding Claim 1, Koo et al. teaches a positive electrode (Para. [0019]) for a secondary battery (Para. [0021], [0038]) wherein the positive electrode is formed by dry mixing a positive electrode active material, a dry conductive material and a dry binder applying high shear force to the mixture and disposing the mixture on a current collector (Para. [0053]) (i.e. a dry electrode film formed by dry mixing comprising an active material, an electrically conductive material and a binder, and a current collector, wherein the dry electrode film is stacked on the current collector), wherein the dry binder is at least one of polyvinylidene fluoride-hexafluoropropylene copolymer and polytetrafluoroethylene (Para. [0034]) (i.e. a fibrillated binder) and the dry conductive material is a carbon fiber (Para. [0053]) (i.e. wherein the electrically conductive material comprises carbon fibers).
Koo et al. does not teach wherein the average diameter of the carbon fibers is 1 to 10 times the average particle diameter of the active material particles to increase the strength of the dry electrode film.
However, Kitano et al. teaches an electrode of a lithium-ion battery (i.e. an electrode for a secondary battery) wherein a carbon fiber is used as a conducting agent (Para. [0176]) (i.e. comprising an electrically conductive material which comprises carbon fibers) wherein the particle diameter of the metal silicon active material in the electrode is 0.8 micrometers (Para. [0214]) and the average particle diameter of the carbon fiber is 3.2 micrometers (Table 2, Example 9) (i.e. wherein an average particle diameter of the carbon fibers is 4 times the average particle diameter of the active material particles, within 1 to 10) and the dispersion is applied onto copper foil and dried (Para. [0220]) (i.e. dry electrode film).
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the average diameter of the carbon fibers of Koo et al. to incorporate the teaching of being 4 times the average particle diameter of the active material particles the average particle diameter of active material particles as taught by Kitano et al., as such an average particle diameter provides a large specific surface area of the carbon fibers involving a large contact area between carbon fibers and active material, enabling high speed charging and discharging (Para. [0053]).
Regarding the functional limitation of “to increase strength of the dry electrode film” modified Koo et al. teaches the same structure as claimed and thus, would be expected to satisfy the function of increasing the strength of the dry electrode film. The reasons regarding expectedness are that the structure is identical to that of the instant claim, therefore it is expected that the dry electrode film of modified Koo et al. would satisfy these conditions. Where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established. "When the PTO shows a sound basis for believing that the products of the applicant and the prior art are the same, the applicant has the burden of showing that they are not." See MPEP 2112.01.
Regarding Claim 4, Koo et al. as modified by Kitano et al. teaches all of the elements of the current invention in claim 1 as explained above.
Koo et al. further teaches the average diameter of the carbon fibers is 50 nm to 300 nm (i.e. within the average diameter of the carbon fibers is 0.05 micrometers to 100 micrometers).
Koo et al. does not teach wherein the average particle diameter of the active material particles is 0.01 micrometers to 20 micrometers.
However, Kitano et al. teaches an electrode of a lithium-ion battery (i.e. an electrode for a secondary battery) wherein a carbon fiber is used as a conducting agent (Para. [0176]) (i.e. comprising an electrically conductive material which comprises carbon fibers) wherein the particle diameter of the metal silicon active material in the electrode is 0.8 micrometers (Para. [0214]) (i.e. wherein the average diameter of the carbon fibers is 0.8 micrometers) and the average particle diameter of the carbon fiber is 3.2 micrometers (Table 2, Example 9) (i.e. wherein an average particle diameter of the carbon fibers is 3.2 micrometers).
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the average diameter of the carbon fibers and active material of Koo et al. to incorporate the teaching of being 3.2 micrometers and 0.8 micrometers. respectively, as taught by Kitano et al., as such an average particle diameter provides a large specific surface area of the carbon fibers involving a large contact area between carbon fibers and active material, enabling high speed charging and discharging (Para. [0053]) and decreased production cost (Para. [0080]).
Regarding Claim 5, Koo et al. as modified by Kitano et al. teaches all of the elements of the current invention in claim 1 as explained above.
Koo et al. further teaches the dry conductive material is present in an amount of 2 wt% to 4 wt% based on the total weight of the positive electrode active material layer (Para. [0031]) (i.e. wherein an amount of the carbon fibers is within 0.1 to 5% by weight based on a total weight of the dry electrode film).
Regarding Claim 6, Koo et al. as modified by Kitano et al teaches all of the elements of the current invention in claim 5 as explained above.
Koo et al. further teaches the dry conductive material includes at least one of a carbon nanotube and a carbon fiber (Para. [0025]) (i.e. wherein the electrically conductive material further comprises an additional material, wherein the additional material is not the carbon fibers), and the dry conductive material is present in an amount of 2 wt% to 4 wt% based on the total weight of the positive electrode active material layer (Para. [0031]) (i.e. wherein an amount of the additional material is at the very least overlapping with the range of 0.1 to 5% by weight based on a total weight of the dry electrode film). In the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990).” See MPEP §2144.05(I).
Regarding Claim 7, Koo et al. as modified by Kitano et al. teaches all of the elements of the current invention in claim 1 as explained above.
Koo et al. further teaches the length of the carbon fibers is 1 micrometer to 50 micrometers (Para. [0029]), overlapping with the claimed range of 5 micrometers to 1500 micrometers. In the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976); In re Woodruff, 919 F.2d 1575, 16 USPQ2d 1934 (Fed. Cir. 1990).” See MPEP §2144.05(I).
Regarding Claim 8, Koo et al. as modified by Kitano et al. teaches all of the elements of the current invention in claim 1 as explained above.
Koo et al. further teaches the dry binder (i.e. the fibrillated binder) is at least one of polyvinylidene fluoride-hexafluoropropylene copolymer (i.e. polyvinylidene fluoride-hexafluoropropylene) and polytetrafluoroethylene (Para. [0034]).
Regarding Claim 9, Koo et al. as modified by Kitano et al. teaches all of the elements of the current invention in claim 1 as explained above.
Koo et al. further teaches a secondary battery including the positive electrode (i.e. a secondary battery comprising the electrode of claim 1) (Para. [0038]).
Regarding Claim 10, Koo et al. as modified by Kitano et al. teaches all of the elements of the secondary battery in claim 9 as explained above.
Koo et al. further teaches the secondary battery is a lithium secondary battery (Para. [0075]).
Regarding Claim 11, Koo et al. teaches a positive electrode is formed by (i.e. a method of manufacturing an electrode, wherein the method comprises the steps of: ) dry mixing a positive electrode active material, a dry conductive material and a dry binder(i.e. forming a primary mixture by dry mixing an active material, an electrically conductive material and a binder, and a current collector) applying high shear force to the mixture (i.e. forming a secondary mixture by applying a force to the primary mixture) (Para. [0053]) and rolling of the current collector on which the mixture is disposed including applying pressure by roll pressing including a roll for applying pressure on the mixture and the current collector, and a belt for moving the current collector (i.e. forming a film by pressing the secondary mixture, placing the film on the current collector, and rolling the film and the current collecting rolling them) (Para. [0059]) and the dry conductive material is a carbon fiber (Para. [0053]) (i.e. wherein the electrically conductive material comprises carbon fibers).
Koo et al. does not teach wherein the average diameter of the carbon fibers is 1 to 10 times the average particle diameter of the active material particles to increase the strength of the dry electrode film.
However, Kitano et al. teaches an electrode of a lithium-ion battery (i.e. an electrode for a secondary battery) wherein a carbon fiber is used as a conducting agent (Para. [0176]) (i.e. comprising an electrically conductive material which comprises carbon fibers) wherein the particle diameter of the metal silicon active material in the electrode is 0.8 micrometers (Para. [0214]) and the average particle diameter of the carbon fiber is 3.2 micrometers (Table 2, Example 9) (i.e. wherein an average particle diameter of the carbon fibers is 4 times the average particle diameter of the active material particles, within 1 to 10) and the dispersion is applied onto copper foil and dried (Para. [0220]) (i.e. dry electrode film).
It would have been obvious for one of ordinary skill in the art before the effective filing date of the claimed invention to have modified the average diameter of the carbon fibers of Koo et al. to incorporate the teaching of being 4 times the average particle diameter of the active material particles the average particle diameter of active material particles as taught by Kitano et al., as such an average particle diameter provides a large specific surface area of the carbon fibers involving a large contact area between carbon fibers and active material, enabling high speed charging and discharging (Para. [0053]).
Regarding the functional limitation of “to increase strength of the dry electrode film” modified Koo et al. teaches the same structure as claimed and thus, would be expected to satisfy the function of increasing the strength of the dry electrode film. The reasons regarding expectedness are that the structure is identical to that of the instant claim, therefore it is expected that the dry electrode film of modified Koo et al. would satisfy these conditions. Where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established. "When the PTO shows a sound basis for believing that the products of the applicant and the prior art are the same, the applicant has the burden of showing that they are not." See MPEP 2112.01.
Regarding Claim 12, Koo et al. as modified by Kitano et al. teaches all of the elements of the current invention in claim 11 as explained above.
Koo et al. further teaches the high shear force is 50 N to 1000 N (Para. [0057]).
Regarding Claim 13, Koo et al. as modified by Kitano et al. teaches all of the elements of the current invention in claim 11 as explained above.
Koo et al. further teaches dry mixing may be performed by mixing at 600 to 1800 rpm at room temperature or below using an agitating machine (Para. [0055]) (i.e. wherein the dry mixing is performed by a mixer within 600 rpm to 20000 rpm at room temperature or lower).
Regarding Claim 14, Koo et al. as modified by Kitano et al. teaches all of the elements of the current invention in claim 11 as explained above.
Koo et al. further teaches the high shear force includes shear-compressing the mixture (Para. [0056]) (i.e. wherein the force is a high shear force for compressing the primary mixture).
Claim 15 is rejected under 35 U.S.C. 103 as being unpatentable over Koo et al. (EP 3609000A1) in view of Kitano et al. (EP 3252193A), as applied to claim 11 above, and further in view of Zhong et al. (US 2013/0255872).
Regarding Claim 15, Koo et al. as modified by Kitano et al. teaches all of the elements of the current invention in claim 11 as explained above.
Koo et al. teaches the mixture receives pressure from the roll including compressive force (i.e. wherein the secondary mixture is pressed by a roll).
Koo et al. does not teach a two roll mill.
However, Zhong et al. teaches a method for making an electrode (Para. [0077]) wherein a two roll mill is used to press a mixture of powders (Para. [0079]).
The substitution of the two roll mill for pressing as taught by Zhong et al., for the roll press device of Koo et al. would achieve the predictable result of providing a roll press device for pressing a mixture of powders in a method of manufacturing an electrode (Para. [0079] of Zhong et al. and Para [0061] of Koo et al.). Therefore it would have been obvious to one having ordinary skill in the art at the time the claimed invention was filed to substitute the two roll mill for pressing as taught by Zhong et al., for the roll press device of Koo et al, as the substitution would achieve the predictable result of providing a roll press device for pressing a mixture of powders in a method of manufacturing an electrode (Para. [0079] of Zhong et al. and Para [0061] of Koo et al.). The simple substitution of one known element for another is likely to be obvious when predictable results are achieved. See KSR International Co. v. Teleflex Inc., 550 U.S. 398, 415-421, USPQ2d 1385, 1395 – 97 (2007) (see MPEP § 2143, B.).
Response to Arguments
Applicant's arguments filed August 26, 2026 have been fully considered but they are not persuasive.
Applicant argues Kitano et al. is totally silent regarding that such diameters would increase the strength of the electrode and would not way to knowing that such a structure would lead to increased strength.
Examiner respectfully disagrees. Regarding the functional limitation of “to increase strength of the dry electrode film” modified Koo et al. teaches the same structure as claimed and thus, would be expected to satisfy the function of increasing the strength of the dry electrode film. The reasons regarding expectedness are that the structure is identical to that of the instant claim, therefore it is expected that the dry electrode film of modified Koo et al. would satisfy these conditions. Where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established. "When the PTO shows a sound basis for believing that the products of the applicant and the prior art are the same, the applicant has the burden of showing that they are not." See MPEP 2112.01. Thus, the argument is not persuasive.
Applicant argues Kitano is not directed to a dry electrode film and has nothing to do with dry mixing and thus, one of ordinary skill in the art would not combine Kitano with Koo because they are directed to two different methods.
Examiner respectfully disagrees. Regarding claim 1, they product claims do not require the limitations of the process “dry mixing” as claimed as this is a product-by-process limitation. Regarding claim 11, the structure of the average diameter of the carbon fibers to average diameter of active material particles ratio would have a reasonable expectation of success in the electrode film method (and product) of Koo et al. as both produce dried electrode film layers (see Para. [0053] – Koo et al.; Para. [0220] – Kitano et al.). The dry mixing method does not preclude the average particle diameter ratio as taught by Kitano et al. from being incorporated as the dispersion liquid is dried nor prevent its benefits (large contact area between providing high speed charging and discharging, Para. [0053]) form being achieved.
Applicant argues the electrode active-material layer of the claimed invention mixes the electrode active material and the carbon fibers and incorporates the resulting mixture into the electrode active-material layer which contrasts with Kitano and does not disclose the size relationship between the carbon fibers and an active material mixed therewith.
Examiner respectfully disagrees. Regarding the method steps claimed, Koo et al. is relied upon rather than Kitano et al. In response to applicant's arguments against the references individually, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986). Regarding the size relationship, Kitano et al. explicitly teaches the particle diameter of the metal silicon active material in the electrode is 0.8 micrometers (Para. [0214]), physical properties of the obtained carbon fibers are shown in Table 2 (Para. [0217]) and the average particle diameter of the carbon fiber is 3.2 micrometers (Table 2, Example 9). Thus, the size relationship between the average particle diameter of the carbon fibers to the average particle diameter of the active material particles is inherently 3.2:0.8. An inherent feature does not need to be recognized by the art at the time of the invention, but only that the subject matter is in fact inherent in the prior art reference. See MPEP §2112(II). Thus, the argument is not persuasive.
Applicant argues unpredictable effects are achieved by the claimed invention based on Experimental Examples 1 and 2 set forth in the specification in terms of improvement in strength, initial discharge efficiency and capacity retention.
Furthermore, applicant appears to be arguing unexpected results. However, the burden to show unexpected results, as required by MPEP 716.02 has not been provided. Examiner suggests Applicant review MPEP 716.02 in full to see the burden that must be met to show unexpected results. For example, the unexpected result is not a comparison to the closest prior art, see MPEP 716.02(e). Furthermore, no data is shown for capacity retention or initial discharge efficiency for Examples 1 and 2; and the statistical significance of the strength of Examples 1 and 2 has not been established. The evidence relied upon should establish "that the differences in results are in fact unexpected and unobvious and of both statistical and practical significance." see MPEP 716.02(b). Thus, the argument is not persuasive.
Applicant argues that the dependent claims are distinct from the prior art of record for the same reason as the independent claim.
Examiner respectfully disagrees. The rejection with respect to the independent claim has been maintained, and thus the rejections to the dependent claims are maintained as well.
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 ARMINDO CARVALHO JR. whose telephone number is (571)272-5292. The examiner can normally be reached Monday-Thursday 7:30a.m.-5p.m..
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/ARMINDO CARVALHO JR./Primary Examiner, Art Unit 1729
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