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 . If status of the application as subject to 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 a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
Status of Claims
Claims 1-8 & 11-15 are pending in the application. Claims 8 and 11-15 are withdrawn. Claims 1-7 and 10 were rejected in the office action mailed 1/16/2026. Applicant cancelled claim 10. Claims 1-7 are presently examined.
Response to Amendment / Arguments
The 4/15/2026 amendment, in response to the 1/16/2026 office action, has been entered.
Regarding the priority claim, Examiner reviewed Applicant’s comments, reviewed MPEP 1893.03(b) and other law regarding the issue, and discussed this with Examiner’s supervisor, Allison Bourke. Applicant's arguments are not persuasive. In order to claim priority to KR1020190171448 with a PCT, the USA application must have been filed no more than 30 months after filing KR1020190171448. Applicant, however, filed the USA application more than 30 months after filing KR1020190171448.
It is unclear why the Applicant referred to filing of the English translation. Examiner made this determination based on the filing date of the USA application – not based on the filing of the English translation.
Examiner suggests discussion of this issue in an interview or review of the PCT timeline in https://www.uspto.gov/web/offices/pac/mpep/s1842.html.
Note that this priority claim failure doesn’t affect the presently-cited prior art because the effective date for all of this prior art is prior to the filing date of KR1020190171448 and the PCT.
Applicant’s claim amendments overcame the 35 U.S.C. 102 and 35 U.S.C. 103 rejections; nevertheless, the claims remain rejected under 35 U.S.C. 103 due to additional prior art.
Priority
Acknowledgment is made of applicant's claim for priority under 35 U.S.C. 119(a)-(d) or (f), 365(a) or (b), or 386(a) based upon an application (KR1020190171448) filed in Korea on 12/20/2019. The claim for priority cannot be based on this application because the subsequent USA nonprovisional application was filed more than 31 months thereafter.
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
Determining the scope and contents of the prior art.
Ascertaining the differences between the prior art and the claims at issue.
Resolving the level of ordinary skill in the pertinent art.
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.
The claims are in bold font, the prior art is in parentheses.
Claims 1-5 are rejected under 35 U.S.C. 103 as being unpatentable over US20150372292A1 (Yokoi) in view of US20150263379A1 (Xiao).
With regard to claim 1, Yokoi teaches the following claim limitations:
A method of manufacturing a negative active material (paragraphs 58-59) for lithium secondary battery (abstract), comprising:
coating a negative active material precursor containing Si with crude tar (paragraphs 27 & 58-59: coal tar coating layer on Si/SiOx base particles)
Regarding the claim limitation for “crude tar”, the present specification states that “The crude tar refers to coal tar” (page 8, line 3). Yokoi teaches coal tar (paragraph 59).
Claim 1 also recites:
the crude tar contains a low molecular weight component that can be removed by a distillation process in an amount of 20 wt% or less
Yokoi fails to describe the volatile / low molecular weight components in the coal tar. Coal tar, however, has various of such volatiles, which can be removed at an amount of ≤ 20 wt%, depending on the temperature and duration of distillation1,2.
Yokoi also teaches the following claim 1 limitations:
annealing an obtained coating product (paragraph 66: heat-treated at 900° C)…
a content of the crude tar is 2 wt% to 20 wt% with respect to 100 wt% of the negative active material precursor (paragraph 59: coal tar is 5 mass % of the negative electrode active material)
Yokoi, however, fails to teach the following claim 1 limitation, which is taught by Xiao:
the negative active material precursor containing the Si is a Si-C composite (paragraph 18: the negative active material can include a silicon-carbon composite)
Yokoi teaches silicon oxide (paragraphs 27 & 58-59). Yokoi, however, fails to teach a silicon-carbon composite, as required by claim 1. Xiao teaches a silicon-carbon composite and silicon oxide as optional negative active materials (paragraph 18).
Xiao thus recognizes the equivalency of silicon-carbon composite and silicon oxide as optional negative active materials. Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filing date, to replace the silicon oxide of Yokoi with the silicon-carbon composite of Xiao. This replacement is merely the selection of functionally equivalent negative active materials recognized in the art. One of ordinary skill in the art would have a reasonable expectation of success in making this replacement.
With regard to claim 2, modified Yokoi teaches the limitations of claim 1 as noted above. Claim 2 recites:
the low molecular weight component has a weight average molecular weight (Mw) of 78 to 128
Yokoi fails to explicitly recite the coal tar chemical composition. Claim 2, however, is merely reciting a molecular weight range of typical crude tar / coal tar composition. Coal tar includes phenol1, which has a molecular weight of 96.
With regard to claim 3, modified Yokoi teaches the limitations of claim 1 as described above. Claim 3 recites:
in the step of the coating the negative active material precursor containing Si with the crude tar, a coating solution prepared by adding the crude tar to a solvent, at a concentration of 50 wt% to 70 wt%, is used
Yokoi teaches 25 wt% coal tar in tetrahydrofuran solvent (paragraph 59). Yokoi’s 25 wt% is outside of the claimed 50-70 wt% range. Increased coal tar concentration would make mixing more difficult, but would reduce drying cost. It would have been obvious, to one of ordinary skill in the art, before the effective filing date of the invention, to adjust the coal tar concentration in the solvent to balance ease of mixing with drying cost.
With regard to claim 4, modified Yokoi teaches the limitations of claims 1 & 3 as described above. Yokoi also teaches the following claim 4 limitation:
the solvent is… tetrahydrofuran… (paragraph 59: tetrahydrofuran)
With regard to claim 5, modified Yokoi teaches the limitations of claim 1 as described above. Claim 5 recites:
the step of coating with the crude tar is performed by: mixing the negative active material precursor and crude tar, and stirring the mixture at a speed of 50rpm to 100rpm for 10 minutes to 60 minutes
Yokoi fails to teach mixing speed and time. Mixing rpm is commonly adjusted in manufacturing processes based on cost (increased rpm requires more expensive equipment), avoiding damaging the mixture (increased rpm can result damaging components in the mixture), and time (increased rpm reduces manufacturing time). It would have been obvious, to one of ordinary skill in the art, before the effective filing date of the invention, to adjust the mixing rpm and time for a balance of cost, avoid damaging the mixture, and reducing mixing time.
Claims 6-7 are rejected under 35 U.S.C. 103 as being unpatentable over US20150372292A1 (Yokoi) in view of US20150263379A1 (Xiao), with regard to claim 1, and further in view of US20190221835A1 (Imaji).
With regard to claim 6, modified Yokoi teaches the limitations of claim 1 as described above. Yokoi also teaches the following claim 6 limitation:
the step of annealing the obtained coating product is carried out at 800°C to 950°C (paragraph 66: heat-treated at 900° C)
Yokoi fails to teach the following claim 6 limitation, which is taught by Imaji:
the step of annealing the obtained coating product is carried out… for 0.5 hours to 2 hours (paragraph 131: one hour)
Imaji is directed to a method of manufacturing a negative active material (paragraphs 46-49), with high specific capacity (abstract), for a lithium secondary battery (title & paragraph 1). Imaji describes coating silicon with coal tar (paragraphs 47 & 55), then heating / firing this coated silicon (paragraphs 49 & 67-68) at 1100° C for one hour (paragraph 131). Although Imaji teaches heating at 1100° C, instead of the 900° C taught by Yokoi, Imaji provides sufficient guidance for one of ordinary skill in the art to select heating time.
It would have been obvious, to one of ordinary skill in the art, before the effective filing date of the invention, to perform the following heating operation:
heat Yokoi’s coal tar coated Si/SiOx base particles at 900° C, as taught by Yokoi; and
heat Yokoi’s coal tar coated Si/SiOx base particles for one hour, for a negative active material with high specific capacity, as taught by Imaji.
With regard to claim 7, modified Yokoi teaches the limitations of claim 1 as described above. Yokoi also teaches the following claim 7 limitation:
the step of annealing the obtained coating product is performed by raising a temperature to a final temperature of 950 °C or less (paragraph 66: heat-treated at 900° C)
Yokoi fails to teach the following claim 7 limitation, which is taught by Imaji:
the step of annealing the obtained coating product is performed by raising a temperature… at a temperature increase speed of 2 °C / min to 10 °C / min (paragraph 131: 250° C/h = 4° C/min)
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 extension fee 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 date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ROBERT WEST whose telephone number is 703-756-1363 and email address is Robert.West@uspto.gov. The examiner can normally be reached Monday-Friday 10 am - 7 pm 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, Allison Bourke can be reached at 303-297-4684.
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/R.G.W./Examiner, Art Unit 1721
/ALLISON BOURKE/Supervisory Patent Examiner, Art Unit 1721
1 https://www.atsdr.cdc.gov/toxprofiles/tp85-c4.pdf
2 https://www.ispatguru.com/coal-tar-and-its-distillation-processes/
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