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
This Office Action is responsive to the amendment filed on 6/18/2026. Claim 23 is amended. Claims 1-7, 10-13, 15-23 are pending. Claim 17 is withdrawn from further consideration as being drawn to a non-elected invention, in accordance with 37 CFR 1.142(b). Applicant’s arguments have been considered. Claims 1-7, 10-13, 15, 16, 18-23 are finally rejected for reasons below.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103(a) which forms the basis for all obviousness rejections set forth in this Office action:
(a) A patent may not be obtained though the invention is not identically disclosed or described as set forth in section 102 of this title, if the differences between the subject matter sought to be patented and the prior art are such that the subject matter as a whole would have been obvious at the time the invention was made to a person having ordinary skill in the art to which said subject matter pertains. Patentability shall not be negatived by the manner in which the invention was made.
Claims 1-3, 5-7, 10-13, 15, 16, 18-23 are rejected under 35 U.S.C. 103(a) as being unpatentable over Youm (EP 3046167) in view of Iyama (JP 2018-110076).
Regarding claim 1, Youm discloses a negative active material composite, comprising: a core and a coating layer around the core,
the core comprising crystalline carbon, amorphous carbon, and silicon nanoparticles, and pores [0005, 0052],
the coating layer comprising amorphous carbon [0011], and
Regarding claim 1, in total the amorphous carbon is comprised in an amount of about 20 wt% to about 80 wt% based on a total weight of the negative active material composite, Youm discloses 5-40% amorphous carbon [0010]. Youm further discloses 10% amorphous carbon coating [0093].
Regarding claim 1, the crystalline carbon is in a form of particles and selected from a natural graphite, an artificial graphite, and a combination thereof [0041].
Regarding claim 1, a total volume of all the pores in the negative active material composite is less than or equal to about 3.0 x 10-2 cm3/g, Youm discloses that a compression-forming method may decrease a size of a pore inside the silicon-graphite composite [0052]. Referring to FIG. 10, the rechargeable lithium battery cells manufactured in a compression-forming method according to Examples 1 to 3 exhibited a small expansion ratio of each electrode plate, compared with the rechargeable lithium battery cell manufactured without compression-forming (according to Comparative Example 1) and the rechargeable lithium battery cell manufactured without adding amorphous carbon before compression-forming (according to Comparative Example 2) [0147]. Accordingly, the negative active material according to an embodiment may show that a volume expansion due to Si particles is minimized and thus, may contribute to realization of a rechargeable lithium battery cell having excellent cycle-life characteristics and storage characteristics at a high temperature [0148].
It would have been obvious to one of ordinary skill in the art at the time the invention was made to reduce the pore size as much as possible for the benefit of obtaining efficient packing of the active material in the composite.
Regarding claim 1, the silicon nanoparticles and the amorphous carbon are comprised in a weight ratio of about 50:50 to about 80:20, and regarding claim 16, the silicon nanoparticles and the amorphous carbon are comprised in a weight ratio of about 60:80 to about 80:20 [0095], Youm discloses in Example 1 [0093], for a given 100 g of the silicon-graphite particle, there is 90 g of 54 wt% graphite, 15 wt% Si and 8 wt% amorphous carbon, after drying the ethanol solvent. In this mixture, there is 70.1 wt% graphite, 19.5 wt% Si, and 10.4 wt% amorphous carbon coal-based pitch, after drying the ethanol solvent. This is equivalent to 63.09 g graphite, 17.55 g Si, and 9.36 amorphous carbon coal-based pitch. Further, the coating possesses 10 grams of amorphous carbon coal-based pitch. There is 17.55 g Si and 9.36 g amorphous carbon, and further 10 g amorphous carbon in the coating. Hence, the ratio of Si and amorphous carbon is 17.55:19.36, or 48:52.
Youm discloses the amorphous carbon may be present inside the graphite particle and this, may help suppress volume expansion of the silicon particle and may help improve-cycle life characteristics of a rechargeable lithium battery [0045]. It would have been obvious to one of ordinary skill in the art at the time the invention was made to adjust the amount of amorphous carbon of Youm depending on the amount of need to suppress volume expansion of the silicon particle.
Youm clearly teaches that silicon is a result effective variable. It has been held by the courts that discovering an optimum value or workable ranges of a result-effective variable involves only routine skill in the art, and thus not novel. In re Boesch, 617 F.2d 272, 205 USPQ 215 (CCPA 1980). See MPEP 2144.05.
Regarding claim 2, the crystalline carbon particles are larger in size than each of the silicon nanoparticles [0040, 0043].
Regarding claim 3, the silicon nanoparticles have an average particle diameter (D50) of about 50 nm to about 150 nm [0093].
Regarding claim 6, the silicon nanoparticles are comprised in an amount of about 20 wt% to about 80 wt% based on the total weight of the negative active material composite [0039].
Regarding claim 7, the amorphous carbon is selected from a soft carbon, a hard carbon, a mesophase pitch, carbonized product, a fired coke, and a combination thereof [0059, 0061].
Regarding claim 10, the crystalline carbon is comprised in an amount of about 20 wt% to about 80 wt% based on the total weight of the negative active material composite [0044].
Regarding claim 11, the negative active material composite has an average particle diameter (D50) of about 2 um to about 15 um [0093].
Regarding claim 12, the coating layer has a thickness of about 1 nm to about 900 nm [0093].
Regarding claim 13, an average pore size of the negative active material composite is less than or equal to about 200 nm, Youm discloses that a compression-forming method may decrease a size of a pore inside the silicon-graphite composite [0052]. The compression-forming method compresses the composite precursor at a pressure between 2MPa to 10 MPa [0060]. It would have been obvious to one of ordinary skill in the art at the time the invention was made to reduce the pore size as much as possible for the benefit of obtaining efficient packing of the active material in the composite.
Regarding claim 15, the negative active material composite has a BET specific surface area of less than or equal to about 10 m2/g [0052].
Regarding claim 18, Youm teaches a negative electrode comprising: a current collector; and a negative active material layer on the current collector and comprising a negative active material, wherein the negative active material comprises the negative active material composite of claim 1.
Regarding claim 19, the silicon nanoparticles in the negative active material composite are comprised in an amount of about 1 wt% to about 30 wt% based on a total weight of the negative active material layer [0093].
Regarding claim 20, Youm teaches a rechargeable lithium battery, comprising: a positive electrode comprising a positive active material; the negative electrode of claim 1; and an electrolyte; wherein the negative active material comprises a mixture of the negative active material composite of claim 1 and at least one additional active material selected from the group consisting of a material that reversibly intercalates/deintercalates lithium ions, a lithium metal, a lithium metal alloy, a material capable of doping/dedoping lithium, and a transition metal oxide, and regarding claim 23, wherein the negative active material composite is included in an amount of about 1 wt% to about 70 wt% based on a total weight of the negative active material layer, Iyama teaches adding a graphite-based negative active material to the negative electrode [0076]. Table 2 shows that the initial charge capacity of the lithium ion secondary battery using the negative electrode material increases as the silicon particle content increase [0079]. It would have been obvious to one of ordinary skill in the art at the time the invention was made to add and adjust the amount of the graphite-based active material to the negative electrode of Youm, as taught by Iyama, depending on the desired initial charge capacity.
Regarding claim 21, the negative active material composite is a compressed negative active material manufactured by compression, under a pressure of about 50 MPa to about 150 MPa, a mixture comprising the crystalline carbon, the silicon nanoparticles, and the amorphous carbon, to achieve the adjacent distance between the silicon nanoparticles of less than or equal to about 100 nm, Youm discloses a mixture comprising the crystalline carbon, the silicon nanoparticles, and the amorphous carbon. Youm discloses that a compression-forming method may decrease a size of a pore inside the silicon-graphite composite [0052]. The compression-forming method compresses the composite precursor at a pressure between 2MPa to 10 MPa [0060]. It would have been obvious to one of ordinary skill in the art at the time the invention was made to increase the pressure of the compression for the benefit to reduce the pore size as much as possible for the benefit of obtaining efficient packing of the active material in the composite.
Regarding claim 22, the negative active material composite is comprised in an amount of about 1 wt% to about 70 wt% based on a total weight of the negative active material layer, Youm discloses 98 wt% negative active material composite in the active material layer with 2 wt% binder and [0099]. It would have been obvious to one of ordinary skill in the art at the time the invention was made to adjust the amount of the active material composite and the binder of Youm depending on the amount of the binder needed in the active material layer, unless the claimed range is critical.
Regarding claim 1, Youm does not disclose an adjacent distance between the silicon nanoparticles being less than or equal to about 100 nm, wherein the silicon nanoparticles have a short axis length of about 20 nm to about 50 nm, and a long axis length of about 50 nm to about 300 nm, wherein the adjacent distance between the silicon nanoparticles is a distance between centers of the adjacent silicon nanoparticles. Regarding claim 5, Youm does not disclose the silicon nanoparticles have an aspect ratio of about 2 to about 8. Youm discloses a silicon particle having an average particle diameter of between about 50 nm to about 300 nm for the benefit of suppressing from a volume expansion due to smooth in-and-out of lithium ions and low ion resistance and cycle-life characteristics [0040]. lyama teaches negative active material in which flat silicon particles having an aspect ratio of 1 to 20 and a thickness of 0.5 um or less, in particular, an aspect ratio of 5 to 10. See Abstract and [0016]. The silicon particles have a carbon layer on the surface of the silicon particles [0008]. When the aspect ratio is 1 or more, the contact area between particles increases, tending to further improve conductivity, and when the aspect ratio is 20 or less, collapse of silicon during charge/discharge cycles is suppressed, tending to result in a longer life for the lithium ion secondary battery [0016]. Further, the thickness of the silicon particles is 0.5 um or less, preferably 0.01 um to 0.4 um, and more preferably 0.05 um to 0.3 um. When the thickness of the silicon particles is 0.5 um or less, then breakdown of silicon during charge/discharge cycles is suppressed, and the lithium ion secondary battery tends to have a long life [0018].
It would have been obvious to one of ordinary skilled in the art at the time invention was made to form the silicon particles of Youm in the form of flat particles disposed as close as possible, with an aspect ratio between 5 to 10, as taught by Iyama, for the benefit of having good conductivity and having long life.
Hence, the prior art combination would entail modifying Youm’s silicon particle with size between 50 nm to about 300 nm by forming them with an aspect ratio of between 5 and 10.
Regarding claim 1, wherein the silicon nanoparticles have a short axis length of about 20 nm to about 50 nm, and a long axis length of about 50 nm to about 300 nm, forming Youm’s silicon particle size between 50 nm to about 300 nm with an aspect ratio of between 5 and 10 would form a short axis length in a range of 300 nm/5 = 60 nm and 50 nm/10=5 nm, greater than 5 nm and less than 60 nm. The long axis length would be less than 300 nm and greater than 50 um. 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.
Regarding claim 1, the adjacent silicon nanoparticles are positioned next to each other in a direction corresponding to the short axis of the silicon nanoparticles and are spaced apart from each other, Youm discloses using a compression-forming method compresses the composite precursor at a pressure between 2MPa to 10 MPa [0060]. Due to the pressure applied to the silicon-carbon nanocomposite, it is reasonable to conclude that the silicon nanoparticles of Youm modified by Iyama are oriented in a direction corresponding to the short axis.
Regarding claim 1, an adjacent distance between the silicon nanoparticles being less than or equal to about 100 nm, Youm discloses that a compression-forming method may decrease a size of a pore inside the silicon-graphite composite [0052]. Referring to FIG. 10, the rechargeable lithium battery cells manufactured in a compression-forming method according to Examples 1 to 3 exhibited a small expansion ratio of each electrode plate, compared with the rechargeable lithium battery cell manufactured without compression-forming (according to Comparative Example 1) and the rechargeable lithium battery cell manufactured without adding amorphous carbon before compression-forming (according to Comparative Example 2) [0147]. Accordingly, the negative active material according to an embodiment may show that a volume expansion due to Si particles is minimized and thus, may contribute to realization of a rechargeable lithium battery cell having excellent cycle-life characteristics and storage characteristics at a high temperature [0128]. It would have been obvious to one of ordinary skilled in the art at the time the invention was made to increase the pressure during the compression-forming step to further minimize the volume expansion of Si. The Examiner notes that a greater pressure applied to the active material composite will decrease the distance between adjacent silicon nanoparticles.
MPEP 2141, III states that “Prior art is not limited just to the references being applied, but includes the understanding of one of ordinary skill in the art. The prior art reference (or references when combined) need not teach or suggest all the claim limitations, however, Office personnel must explain why the difference(s) between the prior art and the claimed invention would have been obvious to one of ordinary skill in the art. The “mere existence of differences between the prior art and an invention does not establish the invention’s nonobviousness.” Dann v. Johnston, 425 U.S. 219, 230, 189 USPQ 257, 261 (1976).
Claim 4 is rejected under 35 U.S.C. 103(a) as being unpatentable over Youm (EP 3046167) in view of Iyama (JP 2018-110076) as applied to claim 1, further in view of Otsuka (US 2017/0040610).
Regarding claim 4, an X-ray diffraction (XRD) peak of a (111) plane of the silicon nanoparticles has a full width at half maximum (FWHM) of about 0.3° to about 7°, Otsuka teaches a negative electrode material containing silicon-containing particles, graphitic carbon particles, and carbon material (Abstract). the composite material according to the present invention has a full width at half maximum of 111 diffraction peak derived from silicon, as observed in the X-ray diffraction with CuK . radiation, of preferably 0.3o to 0.5 o in terms of a scatter angle (2). If the full width at half maximum on the (111) plane is within the range, a balance between cycle retention rate and initial charge and discharge efficiency is improved. Moreover, from a viewpoint of improving the cycle retention rate in the lithium ion battery, the full width at half maximum of the 111 diffraction peak is preferably 0.3 o or more, further preferably 0.5 o or more, and still further preferably 0.7 o or more in terms of the scatter angle (2) [0077]. It would have been obvious to one of ordinary skill in the art at the time the invention was made to adjust the full width at half maximum of 111 diffraction peak derived from silicon, as taught by Otsuka, for the benefit of having good cycle retention rate.
Response to Arguments
Arguments filed 6/18/2026 are addressed below:
Regarding Applicant’s argument on pages 11 and 12, an adjacent distance between the silicon nanoparticles being less than or equal to about 100 nm, Youm discloses that a compression-forming method may decrease a size of a pore inside the silicon-graphite composite [0052]. Referring to FIG. 10, the rechargeable lithium battery cells manufactured in a compression-forming method according to Examples 1 to 3 exhibited a small expansion ratio of each electrode plate, compared with the rechargeable lithium battery cell manufactured without compression-forming (according to Comparative Example 1) and the rechargeable lithium battery cell manufactured without adding amorphous carbon before compression-forming (according to Comparative Example 2) [0147]. Accordingly, the negative active material according to an embodiment may show that a volume expansion due to Si particles is minimized and thus, may contribute to realization of a rechargeable lithium battery cell having excellent cycle-life characteristics and storage characteristics at a high temperature [0128]. It would have been obvious to one of ordinary skilled in the art at the time the invention was made to increase the pressure during the compression-forming step to further minimize the volume expansion of Si. The Examiner notes that a greater pressure applied to the active material composite will decrease the distance between adjacent silicon nanoparticles.
MPEP 2141, III states that “Prior art is not limited just to the references being applied, but includes the understanding of one of ordinary skill in the art. The prior art reference (or references when combined) need not teach or suggest all the claim limitations, however, Office personnel must explain why the difference(s) between the prior art and the claimed invention would have been obvious to one of ordinary skill in the art. The “mere existence of differences between the prior art and an invention does not establish the invention’s nonobviousness.” Dann v. Johnston, 425 U.S. 219, 230, 189 USPQ 257, 261 (1976).
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 CYNTHIA KYUNG SOO WALLS whose telephone number is (571)272-8699. The examiner can normally be reached on M-F until 5pm.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Miriam Stagg can be reached at 571-270-5256. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/CYNTHIA K WALLS/Primary Examiner, Art Unit 1751
