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 .
Election/Restrictions
Applicant’s election without traverse of Group I, claims 1-5, and 10-15 drawn to a negative electrode active material, a negative electrode composition, and a negative electrode, in the reply filed on 09/02/2026 is acknowledged.
Claims 6-9, and 16-17 are withdrawn from further consideration pursuant to 37 CFR 1.142(b) as being drawn to a nonelected invention (Group II), there being no allowable generic or linking claim. Election was made without traverse in the reply filed on 09/02/2026.
Priority
Receipt is acknowledged of certified copies of papers required by 37 CFR 1.55.
Information Disclosure Statement
The information disclosure statements (IDS) submitted on 03/01/2024, 06/07/2024, 12/12/2025, and 02/19/2026 are in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statements are being considered by the examiner.
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.
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, 3-4, 10-11, 13, and 15 are rejected under 35 U.S.C. 103 as being unpatentable over Jo et al. (US 20170309902 A1), in view of Park et al. (US 20180175380 A1) and Chuang (Chuang, Lu-Chung, et al. "Effect of misorientation angle of grain boundary on the interaction with Σ3 boundary at crystal/melt interface of multicrystalline silicon.", 2019, Materialia, 7, 100357).
Regarding claim 1, Jo teaches a negative electrode active material comprising ([0007,0011, 0087]; example 1; porous polycrystalline silicon used as a negative electrode active material):
a silicon-based active material comprising silicon-based grains ([0029, 0087], example 1; porous polycrystalline silicon comprises silicon-based nanograins)
and the silicon-based active material includes a composition that satisfies following
Formulas 1 and 2:
[Formula 1]: about 1 μm ≤ particle size (D50) of silicon-based active material ≤ 10 μm ([0031, 0087]; average particle diameter (D50) of the porous polycrystalline silicon is in a range of 0.01 μm to 50 μm, which encompasses the claimed range)
[Formula 2]: about 2 nm ≤grain size of silicon-based active material ≤1 μm. ([0029, 0087]; average grain size of 3 nm to 300 nm which is within the claimed range).
Specifically, Jo teaches an average particle diameter (D50) of the porous polycrystalline silicon in a range of 0.01 μm to 50 μm ([0031]), including an exemplary average particle diameter (D50) of 5 μm ([0087]). It has been held that in the case where claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists. See MPEP 2144.05 I.
Jo further teaches an average grain size of 3 nm to 300 nm ([0029]) including an exemplary average grain size of 49 nm ([0087]), which lie within the claimed range.
Jo does not teach a limitation wherein a high angle grain boundary ratio in the silicon-based grains is 30% or. Jo does generally introduce the concept of grain boundary in [0023-0024] within the polycrystalline silicon material.
However, Park teaches preparing a silicon-based negative-electrode active material by melting a silicon-containing material followed by rapid cooling/solidification ([0095-0096, 0128]). Park further teaches that rapid solidification produces a crystalline/nano-grain structure ([0096-0097]). Specifically, Park teaches melting silicon together with a matrix material and subjecting the molten material to rapid solidification, whereby the silicon is first crystallized during the cooling process. Park further teaches crystallizing the matrix material on the surface of cooled crystalline silicon to form a crystalline nano-grain layer ([0096-0097]). Park further teaches that nano-grain structure is capable of remarkably suppressing expansion or dispersal of silicon combined with lithium ([0106]). This method employs the same material-forming mechanism disclosed in the instant application. Specifically, the instant application forms the silicon-based active material by rapidly cooling melted-state silicon to form a silicon precursor ([0125-0126] of instant application). Thus, the claimed grain structure is disclosed as resulting from the rapid solidification of melted silicon.
Further, Jo, and Park are considered to be analogous to the claimed invention because both are in the same field of negative electrode active material.
In addition, Chuang further supports this finding by demonstrating that grain boundaries, including high-angle/general grain boundaries, are generated during solidification of molten multicrystalline silicon (Abstract; paragraph 3 of Introduction). Chuang identifies approximately 15° as the conventional transition between small-angle and high-angle/general grain boundaries and experimentally observes grain boundaries having misorientation angles greater than 15° during silicon solidification (paragraph 2 of Results).
Further, modified Jo, and Chuang are considered to be analogous to the claimed invention because both are in the same field of grain boundary of a multicrystalline silicon.
Accordingly, although Jo, as modified by Park and Chuang does not disclose that the high-angle grain-boundary ratio is 30% or more, modified Jo teaches a silicon-based active material having the claimed particle size and grain size and prepared by a melt/rapid-solidification process that is identical or substantially identical, in the relevant material-forming steps, to the process disclosed in the instant application for obtaining the claimed silicon grain structure.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to employ Park's rapid-solidification process in preparing Jo's polycrystalline silicon in order to obtain the crystalline grain structure and achieve the benefits associated with such a nano-grain structure such as suppressing expansion or dispersal of silicon combined with lithium (Park [0093, 0106]). Where the prior art discloses a product that is identical or substantially identical to the claimed product, it is reasonable to conclude that the prior art product inherently possesses the same properties, including high angle grain boundary ratio, absent evidence to the contrary. Accordingly, it would have been obvious that modified Jo’s silicon-based grains necessarily exhibit a high angle grain boundary ratio in the claimed range. See MPEP 2112(V); MPEP 2112.01(I) and (II); MPEP 2145; and MPEP 2145(I).
Regarding claim 3, Jo, as modified by Park and Chuang, teaches all limitation of claim 1 as stated above. Modified Jo further teaches a limitation wherein an average misorientation angle of the silicon-based grains is about 5° or more.
As discussed with respect to claim 1, Chuang teaches that misorientation between silicon grains is generated during solidification of molten multicrystalline silicon and reports a misorientation angle close to 15° (Paragraph 2 of Results).
Therefore, for substantially the same reasons discussed above with respect to claim 1, the silicon-based active material of Jo as modified by Park is identical or substantially identical to the claimed product. In addition, Chuang further confirms that silicon grains formed during solidification exhibit misorientation angles exceeding 5°. Accordingly, where the prior art discloses a product that is identical or substantially identical to the claimed product, it is reasonable to conclude that the prior art product inherently possesses the same properties, including the average misorientation angle, absent evidence to the contrary. Accordingly, it would have been obvious that modified Jo’s silicon-based grains necessarily exhibit an average misorientation angle about 5° or more as claimed. See MPEP 2112(V); MPEP 2112.01(I) and (II); MPEP 2145; and MPEP 2145(I).
Regarding claim 4, Jo, as modified by Park and Chuang, teaches all limitation of claim 1 as stated above. Jo further teaches a limitation wherein the silicon-based active material includes one or more selected from the group consisting of SiOx (x=0) and SiOx (0<x<2), and a content of SiOx (x=0) is about 70 parts by weight or more relative to 100 parts by weight of the silicon-based active material ([0087-0088]).
Specifically, Jo's Example 1 prepares porous polycrystalline silicon powder and uses the resulting powder as the negative-electrode active material ([0087]). Thus, the silicon-based active material is predominantly Si (SiOx, x=0). Jo further teaches in Example 2 that the porous polycrystalline silicon is coated with amorphous carbon, wherein the amorphous-carbon coating is 5 wt% based on the total weight of the negative-electrode active material ([0088]). Accordingly, the resulting active material contains approximately 95 wt% porous polycrystalline silicon, which is greater than the claimed amount of about 70 parts by weight or more.
Regarding claim 10, Jo, as modified by Park and Chuang, teaches all limitation of claim 1 as stated above. Jo further teaches a negative electrode composition ([0009, 0060], a negative electrode comprising the above-described negative-electrode active material) comprising:
the negative electrode active material according to claim 1 (as discussed in claim 1 rejection above)
a negative electrode conductive material ([0061]; conductive agent such as carbon-based material); and
a negative electrode binder ([0062]; binder).
Regarding claim 11, Jo, as modified by Park and Chuang, teaches all limitation of claim 10 as stated above. Jo further teaches a limitation wherein the negative electrode active material accounts for about 40 parts by weight or more of 100 parts by weight of the negative electrode composition ([0060-0062]).
Specifically, Jo teaches that the negative electrode active material layer includes a negative electrode active material and may further include a binder and a conductive agent ([0060]). Jo further teaches that the conductive agent may be included in an amount of 1 wt% to 30 wt% based on total weight of negative electrode active material layer ([0061]) and that the binder may be included in an amount of 1 wt% to 30 wt% based on total weight of negative electrode active material layer ([0062]).
Accordingly, when the conductive agent and binder are each present at the upper end of their expressly disclosed ranges, 30 wt% conductive agent and 30 wt% binder, the remaining 40 wt% of the negative electrode active material layer is the negative electrode active material; at the lower end of the ranges, i.e. 1 wt% conductive agent and 1 wt% binder, the remaining 98 wt% of the negative electrode active material layer is the negative electrode active material. Thus, Jo's disclosed composition encompasses a negative electrode composition in which the negative electrode active material accounts for about 40 parts by weight or more based on 100 parts by weight of the negative electrode composition, as required by claim 11.
Regarding claim 13, Jo, as modified by Park and Chuang, teaches all limitation of claim 10 as stated above. Jo further teaches a negative electrode for a lithium secondary battery ([0009, 0069]), the negative electrode comprising:
a negative electrode current collector layer ([0058, 0063]); and
a negative electrode active material layer provided on at least one surface or both surfaces of the negative electrode current collector layer ([0058, 0063]),
wherein the negative electrode active material layer includes the negative
electrode composition according to claim 10 or a cured product of the negative electrode
composition according to claim 10 (see rejection of claim 10 above).
Specifically, Jo teaches preparing a negative electrode for a lithium secondary battery ([0009, 0069]) by mixing the porous polycrystalline silicon negative-electrode active material with a conductive agent and a binder, applying the resulting negative-electrode composition to a current collector, and drying the composition to form the negative electrode ([0058, 0063]).
Regarding claim 15, Jo, as modified by Park and Chuang, teaches all limitation of claim 13 as stated above. Jo further teaches a lithium secondary battery comprising:
a positive electrode ([0069]);
the negative electrode for the lithium secondary battery according to claim 13 (as discussed with respect to claim 13);
a separator provided between the positive electrode and the negative electrode ([0069]);
and an electrolyte ([0069]).
Claim 2 is rejected under 35 U.S.C. 103 as being unpatentable over Jo, as modified by Park and Chuang, as applied to claim 1 above, and further in view of Li et al. (US 20240002239 A1), and Biswal et al. (US 20140193711 A1).
Regarding claim 2, Jo, as modified by Park and Chuang, teaches all limitation of claim 1 as stated above. Modified Jo does not teach a limitation wherein the silicon-based active material additionally comprises a pulverized product of a silicon precursor,
And the silicon precursor includes a composition that satisfies following Formulas 3 and 4:
[Formula 3]: about 10 μm ≤ plate thickness of silicon precursor ≤2 mm
[Formula 4]: about 2 nm ≤ grain size in silicon precursor ≤1 μm.
However, Li teaches silicon-based particles for use as a negative-electrode material and teaches nano-silicon grains uniformly dispersed in an oxygen-containing silicon-based compound matrix ([0005, 0011-0012]). Li specifically teaches a median nano-silicon grain size of 0.1-25 nm, preferably 0.1-20 nm, more preferably 0.3–15 nm, and still more preferably 0.3-10 nm ([0012]). Thus, Li's disclosed grain-size range overlaps the claimed range of about 2 nm to about 1 μm. It has been held that in the case where claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists. See MPEP 2144.05 I.
Li further teaches preparing the SiOx material by heating a mixture of metal silicon powder and silicon dioxide powder (reading on claimed “product of a silicon precursor”) at 900–1600°C to generate SiOx gas, depositing the SiOx gas on an adsorption plate, removing the resulting deposited sediment after cooling, and thereafter crushing and pulverizing the sediment (reading on claimed “pulverized product”) using a ball mill, jet mill, or other device to obtain SiOx particles ([0059]). Accordingly, Li teaches forming a silicon-containing precursor deposit prior to, and subsequently reducing the precursor by crushing and pulverization to obtain silicon-based particles. Because Li forms the precursor by deposition onto a planar adsorption plate before removing and pulverizing the deposited material, the deposited precursor would have a layer or plate-like configuration corresponding to the claimed silicon precursor with a plate shape. Li further teaches that its silicon-based particles are suitable for use as a battery negative-electrode material and exhibit low expansion rate, long cycle life, high capacity, and high coulombic efficiency (Li [0059, 0005, 0012]).
Further, modified Jo, and Li are considered to be analogous to the claimed invention because both are in the same field of negative electrode active material.
With respect to Formula 3, modified Jo does not disclose the thickness of the precursor sediment deposited on the adsorption plate.
However, Biswal teaches forming a silicon precursor in the form of a porous silicon film/layer and subsequently crushing the silicon material to form silicon particulates for use as an anode material ([0089-0091, 0099]), thus also reading on “a pulverized product of a silicon precursor” as claimed. Biswal specifically teaches a porous silicon layer having a thickness of about 10-200 μm, which falls within the claimed precursor plate-thickness range of about 10 μm to about 2 mm ([0091]). Biswal further teaches that silicon microparticles and nanoparticles formed by crushing the porous silicon layer would extend anode cycle life by controlling lithium intercalation to silicon (Biswal [0092]).
Further, modified Jo, and Biswal are considered to be analogous to the claimed invention because both are in the same field of negative electrode active material.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the silicon-based active material of modified Jo to additionally include silicon-based particles containing nano-silicon grains obtained by forming a silicon-containing precursor deposit and subsequently crushing and pulverizing the precursor, as taught by Li, and to provide the precursor with a thickness within the claimed range, as taught by Biswal, because Li teaches that its silicon-based particles are suitable for use as a battery negative-electrode material and exhibit low expansion rate, long cycle life, high capacity, and high coulombic efficiency (Li [0059, 0005, 0012]), and Biswal teaches forming a porous silicon film/layer having a thickness of about 10–200 μm, which falls within the claimed range to extend anode cycle life by controlling lithium intercalation to silicon (Biswal [0092]). The additional pulverized product of the silicon precursor as taught toward by Li and Biswal would predictably and suitably function as negative active material alongside that within the silicon-based active material of Jo while imparting the above-explained benefits.
Claim 12 is rejected under 35 U.S.C. 103 as being unpatentable over Jo, as modified by Park and Chuang, as applied to claim 10 above, and further in view of Li (US 20240021784 A1).
Regarding claim 12, Jo, as modified by Park and Chuang, teaches all limitation of claim 10 as stated above. Jo further teaches a limitation wherein the negative electrode conductive material includes a linear-type conductive material ([0061]).
Specifically, Jo teaches that the negative-electrode composition may include a conductive agent and identifies suitable conductive agents including carbon fibers, metal fibers, or conductive whiskers ([0061]). Accordingly, carbon fiber, other metal fibers or conductive whiskers, due to their elongated fibrous morphology corresponds to the claimed linear-type conductive material. However, modified Jo does not teach a surface-type conductive material in combination with the linear-type conductive material. Jo does welcome that any conductive agent may be used without particular limitation so long as it has suitable electronic conductivity without causing adverse chemical changes in the batteries, specifically listing examples including graphite such as natural graphite and artificial graphite ([0061]). Jo [0061] also teaches that one alone or a mixture of two or more thereof may be used.
Li, however, teaches that the negative-electrode active-material layer may include at least one conductive agent selected from conductive carbon black, Ketjen black, flake graphite, graphene, carbon nanotubes, and carbon fibers ([0037]). In particular, flake graphite corresponds to a surface-type conductive material, while carbon fibers correspond to a linear-type conductive material. Li's disclosure of “at least one of” the listed conductive agents encompasses the use of more than one of the listed materials.
Further, modified Jo, and Li are considered to be analogous to the claimed invention because both are in the same field of negative electrode active material.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to employ specifically flake-shaped graphite taught by Li as a surface-type conductive material together with carbon fibers as a linear-type conductive material in the negative-electrode composition of modified Jo. Jo already teaches carbon fibers as suitable conductive agents (Jo [0061]) and welcomes additional conductive agents including graphite (Jo [0061]), and Li teaches flake graphite and carbon fibers as suitable conductive agents which are useable together within a negative-electrode active-material layer (Li [0037]). Thus, combining the disclosed conductive materials for their known conductive function would have been a predictable use of known conductive materials, with a reasonable expectation of successfully providing electronic conductivity to the negative electrode. (see MPEP 2143(I)(A-B)).
Claim 14 is rejected under 35 U.S.C. 103 as being unpatentable over Jo, as modified by Park and Chuang, as applied to claim 13 above, and further in view of Kim et al. (KR 20210101540 A, citation from enclosed machine translation).
Regarding claim 14, Jo, as modified by Park and Chuang, teaches all limitation of claim 13 as stated above. Jo further teaches a limitation wherein a thickness of the negative electrode current collector layer is about 1 μm to 100 μm ([0059]).
Specifically, Jo teaches the negative electrode current collector may typically have a thickness of 3 μm to 500 μm ([0059). It has been held that in the case where claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists. See MPEP 2144.05 I.
Modified Jo does not teach a limitation wherein a thickness of the negative electrode active material layer is about 5 μm to 500 μm.
However, Kim teaches negative electrode active material comprises at least one selected from silicon and silicon-based oxide for a lithium secondary battery ([0009, 0023]) wherein the negative electrode active material layer has a thickness of 10 μm to 100 μm ([0065]), which is within the claimed range.
Kim further teaches that controlling the thickness of a silicon-containing negative-electrode active-material layer within this range provides desirable electrode characteristics, and thereby improves lifespan characteristics and prevents an increase in electrode thickness in a negative electrode including a silicon-based material ([0008, 0049, 0052]).
Further, modified Jo, and Kim are considered to be analogous to the claimed invention because both are in the same field of negative electrode active material.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to provide the modified negative-electrode active-material layer of Jo with a thickness as taught by Kim, because Kim teaches such thickness is suitable for a silicon-containing negative-electrode active-material layer used in a lithium secondary battery ([0009, 0023]) to provide excellent capacity characteristics ([0008, 0049, 0052]).
Claim 5 is rejected under 35 U.S.C. 103 as being unpatentable over Li et al. (US 20240002239 A1), in view of Biswal et al. (US 20140193711 A1).
Regarding claim 5, Li teaches a silicon-based precursor comprising plate-shaped silicon.
Specifically, regarding the following limitations:
a silicon-based precursor comprising a composition satisfying following Formulas 3 and 4:
[Formula 3]: about 10 μm ≤ plate thickness of silicon precursor ≤2 mm
[Formula 4]: about 2 nm ≤grain size in silicon precursor ≤1 μm.
Li teaches silicon-based particles satisfying Formula 4, for use as a negative-electrode material and teaches nano-silicon grains uniformly dispersed in an oxygen-containing silicon-based compound matrix ([0005, 0011-0012]). Li specifically teaches a median nano-silicon grain size of 0.1-25 nm, preferably 0.1-20 nm, more preferably 0.3–15 nm, and still more preferably 0.3-10 nm ([0012]). Thus, Li's disclosed grain-size range overlaps the claimed range of about 2 nm to about 1 μm. It has been held that in the case where claimed ranges “overlap or lie inside ranges disclosed by the prior art” a prima facie case of obviousness exists. See MPEP 2144.05 I.
Li further teaches preparing the SiOx material by heating a mixture of metal silicon powder and silicon dioxide powder at 900–1600°C to generate SiOx gas, depositing the SiOx gas on an adsorption plate, removing the resulting deposited sediment after cooling, and thereafter crushing and pulverizing the sediment using a ball mill, jet mill, or other device to obtain SiOx particles ([0059]). Accordingly, Li teaches forming a silicon-containing precursor deposit prior to, and subsequently reducing the precursor by crushing and pulverization to obtain silicon-based particles. Because Li forms the precursor by deposition onto a planar adsorption plate before removing and pulverizing the deposited material, the deposited precursor would have a layer or plate-like configuration corresponding to the plate-shaped silicon precursor.
With respect to Formula 3, Li does not disclose the thickness of the precursor sediment deposited on the adsorption plate.
However, Biswal teaches forming a silicon precursor in the form of a porous silicon film/layer and subsequently crushing the silicon material to form silicon particulates for use as an anode material ([0089-0091, 0099]). Biswal specifically teaches a porous silicon layer having a thickness of about 10-200 μm, which falls within the claimed precursor plate-thickness range of about 10 μm to about 2 mm ([0091]). Biswal further teaches that silicon microparticles and nanoparticles formed by crushing the porous silicon layer would extend anode cycle life by controlling lithium intercalation to silicon (Biswal [0092]).
Further, Li, and Biswal are considered to be analogous to the claimed invention because both are in the same field of negative electrode active material.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the plate-shaped silicon precursor of Li to provide the precursor with a thickness of about 10–200 μm, as taught by Biswal. Because Biswal teaches forming a porous silicon film/layer having a thickness of about 10–200 μm, which falls within the claimed range to extended anode cycle life by controlling lithium intercalation to silicon(Biswal [0092]).
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to Lili Rassouli whose telephone number is (571)272-9760. The examiner can normally be reached Monday-Thursday 8:00 AM-4:00 PM.
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/LILI RASSOULI/ Examiner, Art Unit 1728
/JESSIE WALLS-MURRAY/ Primary Examiner, Art Unit 1728
