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 is a final Office Action in response to Applicant’s remarks and amendments filed on 08/05/2026. Claim 1 is amended. Claims 6-7 are cancelled. Claims 12-17 are withdrawn. Claims 1-5, and 8-17 are pending in the current Office Action.
The objections to the claims set forth in the previous Office Action are withdrawn.
The 35 U.S.C. 103 rejection set forth in the previous Office Action is maintained, with the rejection rewritten below to address the amendments.
Response to Arguments
Applicant's arguments filed 08/05/2026 have been fully considered but they are not persuasive.
Applicant argues that Chen does not disclose the specific material selection for the two carbon layers (see Applicant’s remarks, pg. 7-8, bridging para.) and fails to teach or suggest that the first carbon coating comprises at least one of pitch, graphite, and graphene, and that the second carbon coating layer comprises at least one of carbon black, carbon nanotubes, and carbon nanofibers.
As addressed in the previous Office Action (pg. 6, 2nd full para.) modified Chen discloses the first carbon coating material is preferably graphite, starch, sucrose, polyvinyl alcohol. Furthermore, Chen provides a specific example in which graphite is used as a first carbon coating (Chen, [53]), exhibiting that Chen envisioned graphite, specifically, being used for the first carbon coating, thus providing sufficient motivation for a skilled artisan to select graphite from the list provided by Chen.
Applicant’s assertion that Chen is entirely silent regarding the relative electrical conductivity between the first and second carbon coating layers (see Applicant’s remarks, pg. 8 1st full para.) is addressed below in the rejection of claim 1, rewritten to address the amendment.
Applicant further argues that Kim’s teaching regarding doping of silicon particles is focused on improving the intrinsic conductivity of silicon through elemental doping, which is a fundamentally different concept from controlling the relative conductivity between carbon coating layer on the silicon surface (see Applicant’s remarks, pg. 8-9, bridging para.). As addressed in the previous Office Action (pg. 5, 2nd full para.), Kim taches doping single crystal silicon particles with elements selected from group IIIA and group VA. Furthermore, Kim teaches doping for the benefit of enhancing the electric conductivity of the silicon particles, which is applicable to Chen. The examiner notes that the claim limitation “element-doped silicon nanoparticle” and “wherein the element-doped silicon nanoparticle is a core” simply requires doped silicon-nanoparticles, which modified Chen satisfies. The benefit taught by Kim, enhancing the electric conductivity of the silicon particles, need not be the same benefit sought by Applicant (i.e. specific carbon coatings and relative conductivities).
Furthermore, Kim is not relied upon for the claim limitations recited in amended claim 1 (see Applicant’s remarks, pg. 9, 1st full para.), but rather to teach the doping of the silicon particles, while Chen possesses two carbon coating layers.
Applicant further asserts that the combination of features recited in amended claim 1 provides an unexpected synergistic effect where the second carbon coating layer can provide charge transfer to increase the capacity of the battery while the carbon coating layer serves as a buffer layer to suppress volume expansion (See Applicant’s remarks, pg. 9, 3rd full para., and instant specification, [0051]).
Chen teaches the first carbon coating coated on the surface of the nano silicon acts as a buffer to the volume change of the silicon bacterial during charge and discharge while the second carbon coating allows for high conductivity ([32]), which is similar to the synergistic effect allegedly achieved by Applicant’s claimed invention.
Furthermore, the examiner notes that the claimed element-doped silicon-carbon composite negative electrode material is relatively broad, as it allows for the dopant to be any of a group IIIA, group VA, or transition metal element, and provides multiple materials for the first and second carbon-coating layers. Conversely, Applicant’s most superior results appear to occur when B, Cu, and P, specifically, are used as the dopant element, and flake natural graphite, and carbon black, specifically, are used as the first and second carbon coating layer, respectively (see Instant specifications, [0045];[0048];[0050]-[0051]). Thus, amended claim 1 still appears to be incommensurate in scope with the invention argued to provided Applicant’s alleged synergistic effect. Therefore, Applicant’s argument regarding synergism is not fully persuasive, for at least the above discussed reasons and other differences in scope.
Applicant’s assertion that neither Chen nor Kim alone or in combination teach or suggest the limitations of amended claim 1 is addressed below in the rejection. Furthermore, while Lee does not disclose the claimed combination, Lee is relied upon for the teaching of a carbon nanotube coating layer rather than the specifics of a two-layer structure (see previous Office Action pg. 8, 2nd full para.).
In light of the discussion above, the rejection made in view of Chen, Kim, and Lee is maintained with the rejection rewritten below to address the amendments.
Specification
The disclosure is objected to because of the following informalities:
In [0046], line 1, “FIG. 3” should read, “FIG. 4” as is reasonable in light of [0007] of the instant specification.
In [0047], line 1, “FIG. 4” should read, “FIG. 3” as is reasonable in light of [0007] of the instant specification.
Appropriate correction is required.
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 1-5, and 9-10 are rejected under 35 U.S.C. 103 as being unpatentable over Chen et al. (CN 105958036 A) in view of Kim et al. (US 20170162868 A1), Lee (US 20230238517 A1), and Chen et al. (US20230343943A1), hereinafter Chen ‘943.
Regarding claim 1, Chen discloses a silicon-carbon composite negative electrode material (i.e. carbon-coated silicon anode material, [8]) comprising:
a plurality of silicon-carbon composite negative electrode material particles (i.e. nano-sized silicon particles, carbon-coated silicon anode material [8];[10]), and each silicon-carbon composite negative electrode material comprises a silicon nanoparticle (i.e. nano-sized silicon particles, [10]), a first carbon coating layer ([8]) and a second carbon coating layer ([8]), the silicon nanoparticle (i.e. nano-sized silicon particles, [10]) is a core (i.e. silicon powder covered by carbon coating layers, [8]), and the first carbon coating layer is coated on the silicon nanoparticle (i.e. first carbon coating layer wrapped on outside of silicon powder, [8]), and a second carbon coating layer covers the first carbon coating layer (i.e. second carbon coating layer wrapped on outside of first carbon coating layer, [8]).
Chen is silent regarding the silicon-carbon composite being element-doped, and the dopant element comprising at least one of a group IIIA element, a group VA element, and a transition metal element.
Kim teaches a similar silicon particle coated with a carbon (i.e. conductive single crystal silicon particle, [0015]). Kim further teaches the single crystal silicon particles which are doped such that the impurity contained in the particles may be at least one element selected from B, Al, Ga, and Tl in the case of group III (i.e. group IIIA), or at least one element selected from N, P, As, Sb, and Bi in the case of group V (i.e. group VA) ([0015];[0051];[0122]). Kim further teaches such dopant elements can enhance electric conductivity of the silicon particles ([0051]).
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 element-doped the silicon-carbon composite of Chen where the dopant element comprises at least one element selected from B, Al, Ga, and Tl in the case of group III, or at least one element selected from N, P, As, Sb, and Bi in the case of group V, which is within the scope of claim 1, for the benefit of enhancing the electric conductivity of the silicon-carbon composite, as taught by Kim.
Chen further discloses the first carbon coating material is preferably graphite, starch, sucrose or polyvinyl alcohol ([17]).
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 graphite from the finite list of possible first carbon coating material, with reasonable expectation of success at arriving at a satisfactory first carbon coating for the element-doped silicon-carbon composite negative electrode material.
Chen further discloses the second carbon coating material is desired for high conductivity and electrochemical stability and is at least one of a plurality of layers of graphene, single-layer graphene, graphene oxide, reduced graphene oxide, a graphene-based derivative thereof, polypyrene, polythiophene, polyphenylene, polyacetylene, and polyaniline ([18]).
While Chen discloses such second carbon coating materials, Chen does not appear to necessarily limit the second carbon coating materials and is not particularly against other possible candidates that are able to provide the desired effect.
Modified Chen does not explicitly disclose the material of the second carbon coating layer comprising at least one of carbon black, carbon nanotubes, and carbon nanofibers.
Lee teaches a similar silicon carbon composite anode material (Abstract) with a carbon nanotube layer on the outermost surface of the composite ([0342], Fig. 1, 40). Lee further teaches the carbon nanotube layer serves to improve electrical conductivity of the anode material while securing good high capacity/high output characteristics thereof ([0341]). Furthermore, a skilled artisan would recognize that carbon nanotubes are formed by rolling sheets of graphene and thus are a reasonable substitutional equivalent to the materials disclosed by Chen for the second carbon coating material ([18]).
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 used carbon nanotubes for the second carbon coating layer of modified Chen with reasonable expectation of success in achieving a satisfactory second carbon coating layer, and for the benefit of improved electrical conductivity of the anode material along with good high capacity/high output characteristics, as taught by Lee and desired by modified Chen.
While modified Chen discloses that the first carbon coating acts as a buffer for the volume change of the silicon material during charge and discharge, and the second carbon coating uses graphene which has high electrical conductivity (Chen, [32]), modified Chen does not explicitly disclose an electrical conductivity of the second carbon coating layer is greater than an electrical conductivity of the first carbon coating layer.
Similar to modified Chen, Chen ‘943 teaches the silicon compound coated with the graphene (i.e. first carbon coating layer) and then with the carbon nanotubes (i.e. second carbon coating layer) forms a layered structure that is more conducive to suppressing swelling of silicon in the negative electrode during cycling of the battery, and improving the cycling performance of the battery, in comparison to when the silicon compound is coated with carbon nanotubes and then with graphene ([0042];[0101]).
As modified Chen’s disclosed composite is substantially similar to that of applicant’s claimed invention (i.e. first carbon coating layer of graphite and second carbon coating of carbon nanotubes), and to conform to modified Chen’s desire for the inner coating to accommodate the expanding silicon composite, and the outer coating for conductivity, a skilled artisan would appreciate the second carbon coating layer to be greater in electrical conductivity than the first carbon coating layer.
Furthermore, Lee teaches a carbon nanotube layer formed on the outer circumferential surface of the soft coating layer which contains soft carbon and is formed on the outer circumferential surface of the hard coating layer ([0341]; [0334]). Lee further teaches the amorphous coating layer surrounding the silicon porous matrix may include hard carbon prepared by sintering graphite balls and/or pitch ([0031]). The carbon nanotube layer serves to improve electrical conductivity of the anode material while securing good high capacity/high output characteristics ([0341]).
Lee further demonstrates an increase in electrical conductivity from 12.1 S/cm to 45.1 S/cm for Comparative Example and Example 1, respectively (Table 1). Example 1 is Lee’s taught composite of a core surrounded by a hard coating layer, soft coating layer, and an outer coating of carbon nanotubes ([0555]). The Comparative Example comprises carbon nanotube layer formed on the surface of the sintered product and a hard coating layer on the outer circumferential surface ([0578]). Thus, Lee teaches a higher overall conductivity is achieved with an outer circumferential layer of carbon nanotubes.
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 an electrical conductivity of the second carbon coating layer greater than an electrical conductivity of the first carbon coating layer, as desired by Chen, and suggested by Chen ‘943 and Lee, to achieve a composite with improved cycling performance and electrical conductivity, and to suppress swelling of the silicon-containing particles during cycling.
Regarding claims 2 and 3, modified Chen discloses all limitations as set forth above.
Modified Chen discloses using silicon powder that is dispersed into nano-sized silicon particles (Chen, [10]) and thus does not contain silicon oxide as claimed in claim 2, and wherein the mass percentage of silicon oxide in the element-doped silicon-carbon composite negative electrode material is 0% which is within the claimed less than or equal to 0.1% of claim 3.
Regarding claims 4 and 5, modified Chen discloses all limitations as set forth above. Modified Chen discloses the element-doped silicon-carbon composite negative electrode material is doped such that the impurity contained in the particles (Kim, [0015]), which is within the scope of the claimed “wherein the element-doped silicon nanoparticle comprises a silicon matrix and a dopant element located in the silicon matrix" of claim 4.
Modified Chen further discloses the dopant elements may be at least one element selected from B, Al, Ga, and Tl in the case of group III, or at least one element selected from N, P, As, Sb, and Bi in the case of group V (Kim, [0015]) which is within the claimed dopant elements of claim 5.
Regarding claims 9 and 10, modified Chen discloses all limitations as set forth above.
Modified Chen discloses the element-doped silicon-carbon composite negative electrode material is doped such that the impurity contained in the particles may be at least one element selected from B, Al, Ga, and Tl in the case of group III, or at least one element selected from N, P, As, Sb, and Bi in the case of group V (Kim, [0015]) which significantly overlaps with the claim limitation, “comprises two or more kinds of dopant elements” of claim 10.
Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filing date, to have selected within the significantly overlapped portion of the scope of the claim with reasonable expectation of success in arriving at a satisfactory element-doped silicon-carbon composite negative electrode material.
Modified Chen further discloses an exemplary embodiment wherein the element-doped silicon-carbon composite negative electrode material consists of one kind of dopant element, boron (i.e. boron (B)-doped silicon single crystal, Kim, [0122]), thus satisfying the claim limitation, “consists of one kind of dopant element” of claim 9.
Claim 8 is rejected under 35 U.S.C. 103 as being unpatentable over Chen et al. (CN 105958036 A), Kim et al. (US 20170162868 A1), Lee (US 20230238517 A1), and Chen et al. (US20230343943A1), as applied to claim 1 above, and in further view of Park et al. (KR 20200022729 A).
Regarding claim 8, modified Chen discloses all limitations as set forth above.
Modified Chen discloses the silicon powder with particle size of 1-100 µm, preferably 5-30 µm, is dispersed for 3-20 hours into nano-sized silicon particles (Chen, [10];[21]).
While modified Chen does not explicitly disclose the size of the resulting nanosized silicon particles, the thickness of the two coating layers, or the overall particle size, modified Chen in possessing two coating layers, necessarily and inherently possesses a thickness for each coating layer and thus possesses a diameter of the element-doped silicon-carbon composite negative electrode material particle.
Park teaches similar negative electrode active material consisting of a silicon-based core, a first coating layer positioned on the silicon-based core, and a second coating layer positioned on the first coating layer ([0022]). Park further teaches the average particle diameter D50 of the negative active material may be 0.05 to 40 µm, ([0045]), which encompasses the claimed range of 10 to 20 µm. Park further teaches when the average particle diameter is 0.05 µm or more, the density of the electrode can be prevented from being lowered to have a proper capacity per volume, and when the average particle diameter is 40 µm or less, the slurry for forming the electrode is appropriately uniform in thickness ([0046]).
Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filing date, to have routinely selected and optimized within the encompassed portion of the ranges to achieve the desired balance between capacity per volume of the negative electrode active material, and slurry formation, as taught by Park (MPEP 2144.05 II).
Claim 11 is rejected under 35 U.S.C. 103 as being unpatentable over Chen et al. (CN 105958036 A), Kim et al. (US 20170162868 A1), Lee (US 20230238517 A1), and Chen et al. (US20230343943A1), as applied to claim 1 above, and in further view of Choi et al. (US 20200280059 A1).
Regarding claim 11, modified Chen discloses all limitations as set forth above.
Modified Chen discloses the silicon powder with particle size of 1-100 µm, preferably 5-30 µm, is dispersed for 3-20 hours into nano-sized silicon particles (Chen, [10];[21]) but does not explicitly disclose the size of the resulting nanosized silicon particles.
Choi teaches a similar negative electrode active material with a silicon core. Choi further teaches the average particle diameter D50 of the silicon core to be particularly 80 nm to 150 nm, which overlaps with the claimed range of 10 to 100 nm, as when the particle diameter satisfies this range, the nano-silicon core does not break easily during charge and discharge of the battery and intercalation and deintercalation of lithium may be effectively performed ([0024]).
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 the overlapping portion of the ranges with reasonable expectation of success in achieving a nano-silicon core that does not break easily during charge and discharge of the battery and allows for proper intercalation and deintercalation of lithium.
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 ESTHER J TAN whose telephone number is (571)272-3479. The examiner can normally be reached M-F 7:30 AM-4:00 PM.
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/E.J.T./Examiner, Art Unit 1751
/Haroon S. Sheikh/Primary Examiner, Art Unit 1751
