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 .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 8/12/2026 has been entered.
Response to Amendment
The amendment filed 6/10/2026 is entered and fully considered.
The Declaration under 37 CFR 1.132 filed 6/10/2026 is insufficient to overcome the rejection of claims 20-39 based upon JIN (US 2021/0013499) in view of JIANG et al. (US 2021/0280860) as set forth in the last Office action because:
In paragraph 4, the declarant asserts that using larger graphite flakes facilitate more effective unfolding and restructuring process during spheroidization promoting the formation of composite materials with improved structural integrity and homogenous incorporation of the silicon-containing material. The declaration points to the examples and table 1 using BNB90 (d50 of 43µm) and M17 graphite (d50 of 16µm) according to applicant’s specification. However, the specification also states “Figures 10 and 11 represent the reversible capacities obtained from cells C1, C2, C3, and C4 recorded during the cycling at 1 C, respectively for M1, M2, M3 and ,M4 materials. The cycle life curves show very similar shape and slopes, which indicates that the shaping of the materials does not adversely affect materials performances.” Page 42 lines 22-26. This language hardly suggests the recognition of an unexpected superior result from the particle size. The evidence is intended to show the effect of the shaping process which compares C1 to C2 and compares C3 to C4.
In addition, the specification indicates that the ICE and first CE tests were performed using C/7 while the repeated cycling was done using 1C page 42-43. The C3 battery resulted in superior ICE and maintained a higher average CE over 20 cycles. This evidence further indicates that the C1 (BNB90 graphite) is not necessarily better particularly when operating at a slower discharge rate (C/7).
The declaration also argues that only the 1C discharge testing should be considered when evaluating the unexpected result. The declaration states that the intended use of the battery is for EV applications and the 1C testing is a significant result for that application. However, the examiner notes that even if this was true (EV batteries are intended to be fully discharged after an hour of driving) the claimed method of making batteries is not limited to a particular end use.
The declaration also notes that the ICE parameter is lower for C1 compared to C2 but notes that this was not the primary optimization target. However, choosing to optimize one parameter does not make the result unexpectedly superior.
As for the evidence in Table 1, the examiner notes that a single data point for larger graphite is not commensurate in scope with the claim for a range of graphite sizes. Furthermore, according to the assertions in the declaration it is not clear why there would be any upper limit on the graphite sizes. In addition, the table also shows that the capacity retention is improving faster for the C4 battery than the C2 battery. The faster improving CR with the significantly better ICE for smaller graphite does not clearly indicate that the larger graphite is unexpectedly superior.
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.
Claim(s) 20, 22-24, 28, 29, and 31-39 is/are rejected under 35 U.S.C. 103 as being unpatentable over JIN (US 2021/0013499) in view of AURORA et al. (US 2018/0198116) and SPAHR et al. (US 2012/0077035) and JIANG et al. (US 2021/0280860).
Regarding claims 20, 23, 24 and 35,
JIN teaches a silicon-graphite composite anode active material with silicon located inside the graphite material abstract. The silicon material is deposited on the graphite material using a raw material gas and can be particles (a precursor compound for nanostructured silicon) [0024] and [0028]. The deposition is by CVD [0067]. More specifically, the raw material is provided into a chamber with graphite base material (flakes of carbon-based material) and heated to a reaction temperature of 400-700°C [0088]. The examples show using nitrogen as the atmosphere (removing air and oxygen/dioxygen/O2) [0102]-[0104]. After the silicon is deposited on the graphite (first silicon-carbon composite material) a spheroidizing step is performed to form a core-shell structure with silicon on the inside surrounded by graphite (second silicon-carbon composite material) [0085].
JIN teaches using graphite particle sizes of 4µm in the examples [0102]-[0104]. In addition, the reference teaches natural or artificial graphite with a particle size of 2-20µm [0086] which is understood to be a mean particle size. The reference still does not teach a particle size of 30-100µm. However, generally changes in size are not patentable without showing unexpected results, MPEP 2144.04.IV. In addition, AURORA teaches that when forming graphite shells around silicon by mechanical process, other known carbon materials in addition to natural and artificial graphite includes expanded graphite [0051]. The reference is silent to the exact type of graphite material. However, SPAHR teaches that known conventional expanded graphite in the field of batteries includes BNB90 table 1 and [0032]-[0033]. At the time of filing the invention it would have been prima facie obvious to one of ordinary skill in the art to use expanded graphite BNB90 as the carbon shell material as a simple substitution of known equivalent and conventional carbon materials for forming shells around silicon. The same graphite (BNB90) is expected to have the same size from the manufacturer.
JIN teaches the deposition of silicon can result in silicon particles [0070] but does not expressly teach nanoparticles forming “nanostructured silicon”. However, the same precursor gas deposited on the same substrate at the same temperature will result in the same morphology of the deposited silicon. In addition, JIANG specifically teaches that when making a core shell structure of silicon and graphite, the silicon particles are nanoparticles (30-50nm which falls within the claimed range) while the graphite is micron sized [0021]. At the time of filing the invention it would have been prima facie obvious to use the particle sizes of JIANG as a known particle size for making core shell silicon carbon composite anode active material. The silicon nanoparticle sizes in JIANG fall within the claimed range.
Regarding claim 22,
JIN teaches using the same precursor gas deposited on the same substrate at the same temperature will result in the same morphology of the deposited silicon. In addition, the reference teaches the same mechanical milling to shape the coated graphite into core shell spheres [0102]-[0104]. The same deposition process and the same spheroidization process is expected to form a silicon core with the same physical porosity.
Regarding claim 28,
JIN teaches using the same precursor gas deposited on the same substrate at the same temperature will result in the same deposition coverage of the deposited silicon.
Regarding claim 29
JIN teaches the silicon is located only on the inside of the particle (0% on the exposed outer surface) abstract, [0017], and [0093].
Regarding claim 31,
JIN teaches mechanical milling to form the spheres [0102]-[0104].
Regarding claims 32 and 33,
JIN shows examples of composite particles after spheroidization in fig. 7 [0052]. The particle sizes fall within the claimed range. A particle with rounded corners and a length to diameter ratio of 1:1 is considered to be spheroidized.
Regarding claim 34,
JIN teaches making spherical particles but does not expressly teach the specific surface area. However, spherical particles of the same diameter made of the same material will have the same surface area. Surface area of a sphere is determined by the same equation 4πr2. When the size of the particle is the same (r is equal) the surface area will also be equal.
Regarding claim 36,
JIN teaches the silicon raw material can be silane (SiH4) [0088].
Regarding claim 37,
JIN teaches the silicon graphite material can further have a surface coating formed from a carbon material different from the graphite [0075]-[0076].
Regarding claims 38 and 39,
JIN teaches the silicon graphite composite is for an anode active material and generally teaches making a battery with a positive electrode, negative electrode and electrolyte (separator) therebetween [0031].
Claim(s) 25-27 is/are rejected under 35 U.S.C. 103 as being unpatentable over JIN (US 2021/0013499) in view of AURORA et al. (US 2018/0198116) and SPAHR et al. (US 2012/0077035) and JIANG et al. (US 2021/0280860) further in view of ZHU et al. (US 2014/0248543).
Regarding claims 25 and 26,
JIN teaches forming silicon particles on the graphite particles but does not expressly teach including a catalyst. However, ZHU teaches a method of depositing silicon onto graphite powder substrates abstract. The reference further teaches that catalyzed growth can be done with gold [0008] and [0072]. At the time of filing the invention it would have been prima facie obvious to use gold to catalyze the silicon growth on graphite particles because a catalytic deposition is faster by definition.
Regarding claim 27,
Modified JIN teaches the deposition of silicon particles and nanoparticles on the graphite material. The reference does not expressly teach the formation of nanowires or nanofibers. However, ZHU teaches that when making silicon nanostructures, many different morphologies can be achieved including nanoparticles, nanowires and nanowhiskers [0051]. At the time of filing the invention it would have been prima facie obvious to deposit the silicon on the graphite as nanofibers or nanowhiskers as a simple substitution of known equivalent nanostructures formed on graphite for use in anode active material.
Claim(s) 30 is/are rejected under 35 U.S.C. 103 as being unpatentable over JIN (US 2021/0013499) in view of AURORA et al. (US 2018/0198116) and SPAHR et al. (US 2012/0077035) and JIANG et al. (US 2021/0280860) further in view of KALYAKINA et al. (US 2023/0278877).
Regarding claim 30,
JIN teaches depositing silicon onto graphite using a precursor but does not expressly teach what reactor is used. KALYAKINA generally teaches that when making silicon-carbon composite particles the reactants can be provided into fluidized bed, fixed bed or rotary tube reactors [0071]. At the time of filing the invention it would have been prima facie obvious to use known reactor types, including fixed bed reactors, to make the silicon carbon composite particles.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to AUSTIN MURATA whose telephone number is (571)270-5596. The examiner can normally be reached M-F 8:30-5.
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, MICHAEL CLEVELAND can be reached at 571272-1418. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000.
/AUSTIN MURATA/Primary Examiner, Art Unit 1712
Prosecution Insights