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 .
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 9, 10, 12, and 18 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claims 9, 10, 12, and 18 recite the limitation, "the composite active material particle" (lines 2, 2-3, 2-3, and 2-3, respectively). It is noted that claims 1 and 15 include the limitation, “a plurality of composite active material particles” (lines 2 and 5, respectively). It is unclear which of the composite active material particles is being further limited, and whether applicant desired to further limit a composite active material particle that has a carbon coating or otherwise. For the purposes of this Office Action, claims 9, 10, 12, and 18 have been interpreted as being directed to any of the composite active material particles.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 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 considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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 text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. 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.
Claims 1-11, and 15-18 are rejected under 35 U.S.C. 103 as being unpatentable over Mason et al. (US 20220336790 A1).
Regarding claims 1-5, and 15, Mason discloses an anode active material for a secondary battery ([0001];[0149]) comprising a first active material including silicon (i.e. silicon deposited in pores of porous conductive material, [0007]) and a second active material including carbon (i.e. conductive porous carbon particle framework, [0037]), and a carbon coating covering at least a portion of a surface of at least one of the plurality of composite active material particles ([0079]). Mason further discloses a lithium secondary battery comprising of an anode comprising of the anode active material described above, a cathode, and an electrolyte between the anode and the cathode ([0001];[0149]), reading on claim 15.
Mason discloses a D10, a particle diameter corresponding to a volume fraction of 10%, of at least 2 µm reduces undesired agglomeration of particles and further improves dispersibility of particles ([0070];[0074]). Mason further discloses a D50, a particle diameter corresponding to a volume fraction of 50%, of preferably 4 to 6 µm, which overlaps the scope of claim 5 such that it would have been obvious for one having ordinary skill in the art, before the effective filing date of the claimed invention, to have selected the overlapping portion of the ranges with reasonable expectation that such selection would successfully result in particles with good fluidization properties, improved dispersibility, structural robustness, and high capacity retention over repeated charge-discharge cycles ([0067-0069];[0074]). This yields a D10/D50 of at least 0.33 to 1 which encompasses claim 1’s range of 0.40 to 0.75 such that one of ordinary skill in the art, before the effective filing date of the claimed invention, would have routinely selected within the encompassed portion of the D10/D50 range with a reasonable expectation of achieving an anode active material with satisfactory dispersibility, fluidization properties, structural robustness, and high capacity retention (MPEP 2144.05 I).
It would have been further obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to arrive at the claimed range by routinely optimizing the D10/D50 ratio for the benefits of not only a narrow particle size distribution, but also improved dispersibility of composite particles, good fluidization properties, as well as structural robustness and high capacity retention over repeated charge-discharge cycles (MPEP 2144.05 II).
Mason discloses desired D10, D50, D90, D98 values ([0067-0074]). While Mason does not explicitly disclose a Dmin, a skilled artisan would recognize Mason necessarily possesses a Dmin, a minimum particle diameter. A skilled artisan would further recognize that Mason would necessarily envisage control of Dmin in a manner similar to D10 as set forth above for the sake of reducing undesired agglomeration and improving dispersibility of composite particles ([0070]), thus rendering obvious the claimed ranges of Dmin of claims 3 and 4 for the reason of reducing agglomeration and improving composite particle dispersibility. While Mason does not explicitly disclose a Dmin/D50 ratio, Mason must necessarily possess one. Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to have arrived at the claimed ranges of Dmin/D50 of claims 1 and 2 by way of selecting the encompassed portion of the ranges in an effort to reduce agglomeration and improve dispersibility of the composite particles. (MPEP2144.05 I-II).
Regarding claim 6, Mason discloses all limitations as set forth above.
Mason further discloses the composite particles having BET surface area (i.e. specific surface area) preferably in a range from 2 to 15 m2/g, more preferably no more than 10 m2/g ([0076]), therefore providing sufficient specificity to, while also encompassing, the claimed range of 2 to 8 m2/g. Mason further discloses a low BET surface area is preferred to minimize the formation of the solid electrolyte interphase (SEI) at the surface of the composite particles during the first charge-discharge cycle, but an excessively low BET surface area results in unacceptably low charging rate and capacity ([0076]).
Assuming, arguendo, applicant is able to convincingly prove that the disclosed range is not sufficiently specific, it would still have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to have selected and optimized within the encompassed portion of the ranges for the specific surface area to achieve a desired balance between minimizing SEI formation and an acceptable charging rate and capacity (MPEP 2144.05 I-II).
Regarding claims 7 and 16, Mason discloses all limitations as set forth above.
Mason further discloses a conductive porous carbon particle framework in which silicon is deposited in the pores of the porous conductive composite material ([0007];[0037];[0044]). This reads upon the claim limitation, “wherein at least one of the plurality of composite active material particles has a structure in which at least a portion of the first active material is embedded in the second active material.”
Regarding claims 8 and 17, Mason discloses all limitations as set forth above.
Mason further discloses at least 85% of the electroactive material mass (i.e. silicon) in the composite particles is located within the internal pore volume of the conductive porous particle framework such that there is very little electroactive material located on the external surfaces of the composite particle ([0051]). In other words, Mason discloses at most 15% of the first active material is exposed to the surface of the at least one of the plurality of composite active material particles which is within the scope of the claimed “at least a portion”.
Regarding claim 9, as best understood in view of the 112(b) rejection above, Mason discloses all claim limitations as set forth above.
Mason further discloses the composite particles preferably comprise from 0.35 wt % to 0.65 wt % of silicon ([0047]), and a conductive carbon porous particle framework, wherein the composite particles comprise at least 80 wt % in total of silicon and carbon ([0048]), which falls within the claimed range, per the calculations below.
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Regarding claims 10 and 18, as best understood in view of the 112(b) rejection above, Mason discloses all claim limitations as set forth above.
Mason further discloses the composite particles comprise of a porous conductive particle framework including micropores and/or mesopores (Abstract) which reads on the claim limitation, “wherein the composite active material particle includes a plurality of the pores at an inside or on the surface of the composite active material particle.”
Regarding claim 11, Mason discloses all claim limitations as set forth above.
Mason further discloses the PD50 pore diameter of the conductive porous particle framework is preferably no more than 10 nm ([0093]) which overlaps with the claimed average diameter of the pores being 1 to 500 nm.
It would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to have routinely selected within the overlapping ranges with reasonable expectation of achieving an active material with suitable characteristics (MPEP 2144.05 I).
Claim 12 is rejected under 35 U.S.C. 103 as being unpatentable over Mason et al. (US 20220336790 A1) as applied to claim 1 above, and in further view of Lee et al. (US 20250038181 A1), hereinafter Lee ‘181.
Regarding claim 12, as best understood in view of the 112(b) rejection above, Mason discloses all claim limitations as set forth above.
Mason discloses a high porosity carbon framework in which the pore volume is predominantly micropores, pores less than 2 nm in diameter, has sufficient strength to accommodate the volumetric expansion of silicon without fracturing or degrading the porous carbon framework ([0016];[0019]).
Mason further discloses the conductive porous particle framework is characterized by a total volume of micropores and macropores in the range from 0.4 to 2.2 cm3/g ([0019]), but does not explicitly disclose a porosity of the composite active material particle based on a total volume of the composite active material.
Lee ‘181 teaches as similar silicon-carbon composite anode active material with a porosity of 1% to 40%, which is within with the claimed porosity range of 0.1 vol% to 40 vol% ([0146]). The 1% to 40% being vol% as Lee ‘181 defines porosity (%) = pore volume per unit mass/(specific volume + pore volume per unit mass) ([0150]). Lee ‘181 further teaches a porosity below 1 vol% results in difficulty in controlling the volume expansion of the electrode active material during charge and discharge, while a porosity exceeding 40 vol% reduces mechanical strength of the electrode active material ([0146]).
Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to have selected and/or optimized within the taught range for the porosity to achieve an anode active material that has satisfactory volume expansion characteristics during charge and discharge, while maintaining overall electrode mechanical strength (MPEP 2144.05 I-II).
Claim 13 is rejected under 35 U.S.C. 103 as being unpatentable over Mason (US 20220336790 A1) as applied to claim 1 above, and further in view of Lee et al. (US 20230049476 A1), hereinafter Lee ‘476.
Regarding claim 13, Mason discloses all claim limitations as set forth above.
Mason discloses the composite particles may include a carbon coating to improve conductivity of the surface of the composite particles where the thickness of the carbon coating may suitably be in the range from 2 to 30 nm ([0078-0080]). While Mason does not explicitly disclose a content of the carbon coating in a range from 0.1 wt% to 15 wt% based on the total weight of anode active material, as Mason possesses a carbon coating, the carbon coating must necessarily be present in some wt% based on the total weight of the anode active material.
Lee ‘476 teaches a similar anode active material with a carbon coating with a carbon content of 2% by weight to 30% by weight, based on the total weight of the silicon-silicon complex oxide-carbon composite (i.e. the anode active material, [0145]), which overlaps with the claimed 0.1 to 15 wt %.
Lee ‘476 further teaches if the carbon content of the coating is less than 2% by weight, a sufficient effect of enhancing conductivity cannot be expected and could lead to deterioration of the electrode lifespan, and if the carbon content exceeds 30% by weight, the discharge capacity and bulk density may decrease and the charge-discharge capacity per unit volume may be deteriorated ([0146]).
Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to have selected and optimized within the overlapping ranges for the coating carbon content to achieve a desired balance between conductivity, electrode lifespan, discharge capacity, and bulk density (MPEP 2144.05 I-II).
Claims 14 and 19 are rejected under 35 U.S.C. 103 as being unpatentable over Mason et al. (US 20220336790 A1) as applied to claims 1 and 15 above, and in further view of Kim et al. (US 20190355971 A1).
Regarding claims 14 and 19, Mason discloses all limitations as set forth above.
Mason discloses the carbon of the conductive porous carbon particle framework may be crystalline carbon ([0037]). Mason further discloses a carbon coating is advantageous for its reduction in BET surface area of the particulate material as well as improving the conductivity of the surface of the composite particles ([0080]).
Mason does not disclose the use of a low crystalline carbon for the coating layer, or a coating with lower crystallinity than that of the carbon in the composite particle.
Kim teaches a similar anode active material where a silicon-carbon composite consists of crystalline carbon ([0022]). Kim further teaches an amorphous carbon coating layer on the surface of a silicon-carbon composite further improves the conductivity of the composite and thus may improve performance ([0033-0034]). A skilled artisan would recognize that amorphous carbon is smaller in crystallinity than crystalline carbon.
Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the claimed invention, to improve Mason by utilizing an amorphous carbon coating as taught by Kim such that the carbon coating is of smaller crystallinity than the porous carbon conductive framework of crystalline carbon for the benefit of improved conductivity and performance of the composite.
Conclusion
Examiner notes relevant prior art regarding claims 3 and 4. Lee ‘476 further teaches a Dmin range of 0.1 to 3.0 µm where in satisfying this range, the packing density of particles can be maximized and the printing characteristics of the electrode slurry are excellent ([0049];[0051]).
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ESTHER J TAN whose telephone number is (571)272-3479. The examiner can normally be reached M-F 7:30 AM-4:30PM.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Jonathan Leong can be reached at (571)270-1292. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/E.J.T./Examiner, Art Unit 1751
/JONATHAN G LEONG/Supervisory Patent Examiner, Art Unit 1751 2/4/2026