DETAILED ACTION
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 Nov. 12, 2025 has been entered.
Status of Claims
Claims 1-2, 4-5, 7-11 and 13-24 are pending, wherein claims 1, 8, 13, 19-20 and 23 are amended, and claim 24 is newly added. Claims 1-2, 4-5, 7-11 and 13-24 are being examined on the merits in this office action.
Information Disclosure Statement
The information disclosure statement (IDS) submitted on Oct. 2, 2025 has been considered by the examiner.
Remarks
Applicant’s amendments and arguments have been entered. A reply to the Applicant’s remarks/arguments is presented after addressing the claims.
Any rejections and/or objections made in the previous Office Action and not repeated below, are hereby withdrawn in view of Applicant’s amendments or/and arguments.
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action. References cited in the current Office action can be found in a prior Office action.
Claim Rejections - 35 USC § 112
Claims 1-2, 4-5, 7-11 and 13-24 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.
The range of “from 0.4 to less than 0.8” renders the scope unclear. For example, the range can be from 0.4 to 0.7, from 0.4 to 0.6, from 0.4 to 0.5, and so on. Claim 1 and its dependents are indefinite. It is suggested that the range be modified as “from 0.4 to 0.8”.
The “Area” and “Dmax2” recite in claim 13 are not defined, rendering the claim indefinite.
Claim 16 recites “a tap density” of the artificial graphite. It is unclear as to whether it refers to a tap density in the first graphite (According to claim 14 from which claim 16 depends, the first graphite includes an artificial graphite and a natural graphite) or a tap density before it is mixed with the natural graphite in the first graphite. If it refers to the former, how the tap density is obtained/measured/calculated. Applicant is advised to point out where in the specification the support is.
Claim Rejections - 35 USC § 103
Claims 1-2, 4-5, 7-11, 13-16 and 18-23 are rejected under 35 U.S.C. 103 as being unpatentable over Kim et al. (US 20200403231 A1, hereafter Kim) in view of Oura et al. (US 20220344659 A1, hereafter Oura) and Liao et al. (CN 111146414 A, whose English machine translation is being employed for citation purposes, hereafter Liao).
Regarding claims 1, 8, 10-11 and 24, Kim teaches a negative electrode (“anode” in at least Title and Abstract) for a lithium-ion secondary battery, comprising:
a negative electrode current collector ([0021]), and
a negative electrode active material layer (the combination of a first anode active material layer and a second anode active material layer, disclosed in [0022]-[0023]), wherein the negative electrode active material layer is disposed on at least one of the negative electrode current collector ([0022]).
Kim teaches the negative electrode active material layer including:
a lower layer portion (the first anode active material layer, mentioned above) facing the at least one surface of the negative electrode current collector ([0022]) and comprising a first negative electrode active material that includes a first graphite ([0022]) and a first conductive material ([0050]), and an upper layer portion (the second anode active material layer, mentioned above) disposed on a top of the lower layer portion ([0023]) and comprising a second negative electrode active material that includes a second graphite, silicon oxide ([0023], [0030]), and a linear conductive material (“fibrous carbon”, [0079]). The upper layer portion comprises the second graphite and the silicon oxide at a weight ratio of 91:9 to 99:1 ([0023]), which is close to the range of 70:30 to 90:10 as claimed. A prima facie case of obviousness exists where the claimed ranges and prior art ranges do not overlap but are close enough that one skilled in the art would have expected them to have the same properties. Titanium Metals Corp. of Amer. v. Banner, 778 F.2d 775, 227 USPQ 773 (Fed. Cir. 1985). See at least MPEP 2144.05 (I). In this case, one of ordinary skill in the art would readily appreciate that the small difference of the weight ratio between Kim and that as claimed will not significantly change the property of the upper layer portion. In the absence of unexpected results or persuasive evidence that the difference of weight ratio is significant, the claimed weight ratio is not patentably distinguishable.
Kim is silent as to the linear conductive material being single-walled carbon nanotubes or multi-walled carbon nanotubes. In the same field of endeavor, however, Oura discloses a two-layer negative electrode (See Fig. 2), wherein the two layers each include fibrous carbon, such as single-walled carbon nanotubes (SWCNTs) or/and multi-walled carbon nanotubes (MWCNTs), for maintaining the electrically conductive path ([0062]-[0063]). It would have been obvious to one of ordinary skill in the art before the effective filing date of the instant invention to have employed SWCNTs or/and MWCNTs taught by Oura as the fibrous carbon of Kim in order to maintain the electrically conductive path. Note also that it has been held to be within the general skill of a worker in the art to select a known material on the basis of its suitability for the intended use as a matter of obvious design choice. In re Leshin, 125 USPQ 416. See MPEP § 2144.07.
Kim is silent as to the claimed size and sphericity of silicon particles. In the same field of endeavor, Liao discloses that a mixture of silicon and graphite can be used as a negative electrode active material of a negative electrode of a battery, wherein the D50 of silicon oxide particles can be in the range of 2 µm to 15 µm (at least: [0040]) and a sphericity of silicon particles can be less than 0.8 (at least: [0035]). It would have been obvious to one of ordinary skill in the art before the effective filing date of the instant invention to have incorporated the teachings of Liao into Kim in view of Oura such that the D50 of silicon oxide particles is in the range of 2 µm to 15 µm and the sphericity of silicon oxide particles is less than 0.8 in order to at least significantly improve cycle performance and deformation rate of the battery (at least [0011]). Note also that it has been held to be within the general skill of a worker in the art to select a known material on the basis of its suitability for the intended use as a matter of obvious design choice. In re Leshin, 125 USPQ 416. See MPEP § 2144.07. As a result, the claimed ranges of 3 µm to 10 µm (claim 1), 0.4 to 0.8 (claim 1), and 0.4 to 0.6 (claim 24) lie inside the above-mentioned ranges, respectively. In the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art”, a prima facie case of obviousness exists. See MPEP § 2144.05 (I).
Regarding claims 2 and 18, Kim as modified teaches the negative electrode for a lithium-ion secondary battery according to claim 1, wherein the lower layer portion comprises the first graphite, which may be the only negative electrode active material present in the lower layer portion ([0022]). Therefore, the amount of the first graphite in the lower layer portion is 100 wt% based on the first negative electrode active material present in the lower layer portion.
Regarding claims 4 and 5, Kim as modified teaches the negative electrode for a lithium-ion secondary battery according to claim 1, wherein the silicon oxide comprises SiOx, wherein 0<x<2 ([0030]-[0031], Kim). The claimed range of “x is equal to or more than 0 and less than 2” (claim 4) and “0.5-1.5” (claim 5) overlap the range of 0<x<2, respectively. In the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art”, a prima facie case of obviousness exists. See MPEP § 2144.05 (I).
Regarding claim 7, Kim as modified teaches the negative electrode for a lithium-ion secondary battery according to claim 1, wherein the silicon oxide comprises a metal-doped SiOx, where 0<x<2, and the metal may be at least one selected from Li, Mg and Al ([0035], Kim). One of ordinary skill in the art would appreciate that the metal is distributed on surface of silicon oxide particles, inside of the silicon oxide particles, or on the surface and inside of the silicon oxide particles because it is doped by the metal.
Regarding claim 9, Kim as modified teaches a lithium-ion secondary battery comprising the negative electrode as defined in claim 1 ([0058], Kim).
Regarding claim 13, Kim as modified teaches the negative electrode for a lithium-ion secondary battery according to claim 1. The instant claimed calculation method of sphericity is not patentably distinguishable since a sphericity should not depend significantly on a calculation method or process. Since Kim as modified teaches the sphericity as claimed, the instant invention has been taught.
Regarding claims 14-15, Kim as modified teaches the negative electrode for a lithium-ion secondary battery according to claim 1, wherein the first graphite includes an artificial graphite and a natural graphite ([0022], Kim), and an average particle diameter of the artificial graphite or natural graphite may be in the range of 0.01 µm to 90 µm ([0060], Liao). The claimed ranges lie inside the above range. In the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art”, a prima facie case of obviousness exists. See MPEP § 2144.05 (I).
Regarding claim 16, Kim as modified teaches the negative electrode for a lithium-ion secondary battery according to claim 15, and the claimed tap density of the artificial graphite can be arrived at through routine experimentation since one of ordinary skill in the art can readily, for example, control the number of tapping the artificial graphite while keeping the volume of a container containing the artificial graphite constant.
Regarding claims 19 and 20, Kim as modified teaches the negative electrode for a lithium-ion secondary battery according to claim 1, wherein the first conductive material includes carbon black and can be present in the lower layer portion (at least [0079], Kim).
Regarding claim 21, Kim as modified teaches the negative electrode for a lithium-ion secondary battery according to claim 1, wherein the second graphite includes artificial graphite ([0023], Kim) and an average particle diameter of the artificial graphite may be in the range of 0.01 µm to 90 µm ([0060], Liao). The claimed range lies inside the above range. In the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art”, a prima facie case of obviousness exists. See MPEP § 2144.05 (I).
Regarding claim 22, Kim as modified teaches the negative electrode for a lithium-ion secondary battery according to claim 1, wherein the upper layer portion may comprises a binder in an amount of 1 wt% to 3 wt% and a conductive material in an amount of 1 wt% to 5 wt% based on a total weight of the upper layer portion ([0049]-[0050], Kim), and thus the second negative electrode active material may be in an amount of 92 wt% to 98 wt% based on 100 wt% of the upper layer portion ([0023], Kim).
Regarding claim 23, Kim as modified teaches the negative electrode for a lithium-ion secondary battery according to claim 1, wherein the upper layer portion may comprises a binder in an amount of 1 wt% to 3 wt% and a conductive material in an amount of 1 wt% to 5 wt% based on a total weight of the upper layer portion ([0049]-[0050], Kim), and thus the second negative electrode active material may be in an amount of 92 wt% to 98 wt% based on 100 wt% of the upper layer portion ([0023], Kim).
The claimed range overlaps the range of 92 wt% to 98 wt% disclosed by Kim. In the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art”, a prima facie case of obviousness exists. See MPEP § 2144.05 (I).
Claim 17 is rejected under 35 U.S.C. 103 as being unpatentable over Kim in view of Oura and Liao, as applied to claim 14 above, and further in view of Han et al. (US 2021/0391570 A1, hereafter Han).
Regarding claim 17, Kim as modified teaches the negative electrode for a lithium-ion secondary battery according to claim 14, but is silent as to a weight ratio of 5:5 for the artificial graphite and natural graphite.
In the same field of endeavor, Han discloses that a first negative electrode active material layer disposed on a current collector surface may comprise artificial graphite and natural graphite in an equal amount by weight (at least: [0007]). It would have been obvious to one of ordinary skill in the art before the effective filing date of the instant invention to have used a weight ratio of 5:5 for the artificial graphite and natural graphite included in the first negative electrode active material layer, since it has been held to be within the general skill of a worker in the art to select a known material on the basis of its suitability for the intended use as a matter of obvious design choice. In re Leshin, 125 USPQ 416. See MPEP § 2144.07.
Response to Arguments
Applicant's arguments filed on Nov. 12, 2025 have been fully considered but they are not persuasive.
1) Applicant states that claim 13 is amended (page 8), but it does not appear to have been modified. Applicant’s assertion that “one of ordinary skill in the art knows what the claimed terms “area” and Dmax2” mean” is not persuasive, because one cannot interpretate a claim based on hypothesis. For example, the “Area” refers to image area? Particle area? Other area? It must be defined.
2) In response to the 112 rejection of “tap density”, Applicant did not address the ambiguousness mentioned in the previous office action. The “artificial graphite” in “the artificial graphite has a tap density of …” can independently exist (before mixing with natural graphite) or exist as a mixture with natural graphite. In which case the tap density is being claimed?
3) In response to the argument as to the weight ration of graphite to silicon oxide, please see the art rejection above.
4) In response to the argument associated with Liao’s sphericity, the sphericity as claimed at least overlaps that disclosed by Liao. In the case where the claimed ranges “overlap or lie inside ranges disclosed by the prior art”, a prima facie case of obviousness exists. See MPEP § 2144.05 (I). Note that Liao discloses a range of sphericity, rather than a fixed value of 0.8.
Correspondence
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ZHONGQING WEI whose telephone number is (571)272-4809. The examiner can normally be reached Mon - Fri 9:30 - 6:00.
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/ZHONGQING WEI/Primary Examiner, Art Unit 1727