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 .
Response to Amendment
The Request for Continued Examination filed on February 12, 2026 in response to the Final Office Action mailed on December 17, 2025 was received. Claim 1 was amended and claim 5 was cancelled. Claims 1, 3, 4 and 6-12 are pending in this application.
Response to Arguments
Claim 1 rejection under 35 U.S.C. 103 as being unpatentable over Lee et al. (US 20200365883 A1) in view of Duan, Y. (CN 111261834 A, see machine translation for citation).
As acknowledged on the Final Office Action (page 5), Lee does not teach the feature "wherein a ratio of a content of the silicon-based active material in the second anode active material layer among a total content of the silicon-based active material included in the anode active material layer relative to a content of the silicon-based active material in the first anode active material layer among the total content of the silicon-based active material included in the anode active material layer is 2 or more, and less than 5".
Applicant argues (see pages 8-12) that Duan fails to cure the deficiencies of Lee, because Duan discloses a relative content of the silicon element and does not disclose the absolute content of the silicon-based active material in the first and second anode active material layer as required by the present invention.
Applicant’s arguments, see pages 8-12, filed on February 12, 2026, with respect to claim 1 have been fully considered and are persuasive. The 35 U.S.C. 103 rejection of claim 1 has been withdrawn.
Because of the direct or indirect dependency of claims 3, 4 and 6-12 on claim 1, the 35 U.S.C. 103 rejections applied to these claims have been withdrawn.
Upon further consideration, a new ground(s) of rejection is made in view of Nam, Y. (EP 3591749 A1).
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 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 non-obviousness.
Claims 1, 3, 4, 6, 7 and 9-12 are rejected under 35 U.S.C. 103 as being unpatentable over Nam, Y. (EP 3591749 A1).
Regarding claim 1, Nam teaches a multilayer electrode including an electrode collector; and two or more electrode active material layers which are sequentially coated on one surface or both surfaces of the electrode current collector, wherein the electrode active material layers each include a carbon-based material, a binder, and a silicon-based material [0008]. The multilayer electrode may be a negative electrode and it may be employed on a lithium secondary battery [0015 and 0018]. The silicon-based material may include at least one selected from the group consisting of SiOx (0≤x<2) and Si-alloy [0010]. As binder material, polyvinyl alcohol, among other materials, may be employed [0011], therefore it is possible to select it as the “second binder”.
In the multilayer electrode according to this specific embodiment, the first to the nth electrode active material layers include a silicon-based material in an amount that gradually increases as farther away from the electrode current collector, the (n-1)th electrode active material layer may include a silicon-based material in an amount of 0% to 99% based on the content (% by weight) of the silicon-based material contained in the nth electrode active material layer [0014]. It is taught that “n” is an integer of 2 to 4, or 2 to 3 [0033].
From the previous descriptions, an anode having a “current collector; and an anode active material layer comprising a first anode active material layer and a second anode active material layer sequentially disposed on a surface of the anode current collector each of the first anode active material layer and the second anode active material layer including a silicon-based active material” can be manufactured if n=2.
Because the silicon-based material in the (n-1)th layer (first anode active material layer) can be selected to be between 0-99% by weight the amount of the of the silicon-based material in the nth layer (second anode active material layer), the “ratio of the content of the silicon-based material in the second active material layer relative to the content of the silicon-based active material in the first anode active material” could be in the range of 100-1.01.
Nam is analogous art to the current invention because it is concerned with the same field of endeavor, namely an anode for a lithium secondary battery, comprising: an anode current collector; and an anode active material layer comprising a first anode active material layer and a second anode active material layer sequentially disposed on a surface of the anode current collector, each of the first anode active material layer and the second anode active material layer including a silicon-based active material, wherein the claimed ratio can be overlapped from its teachings, its second binder can be selected as polyvinyl alcohol and the silicon-based material may include at least one selected from the group consisting of SiOx (0≤x<2) and Si-alloy.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to have selected the overlapping portion of the content ratio of the silicon-based material in the second active material layer relative to the content of the silicon-based active material in the first anode active material range calculated from Nam teachings, because overlapping ranges have been held to be a prima facie case of obvious. 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 3, Nam teaches all the elements of the current invention in claim 1. Nam further teaches that styrene butadiene rubber may be used as binder, among other materials [0011], therefore it can be selected as the “first binder”.
Regarding claim 4, Nam teaches all the elements of the current invention in claim 1. Nam further teaches that the second electrode active material layer may include a binder in a reduced amount of 0-99% by weight of the binder which is contained in the first electrode active material layer formed adjacent thereto and closer to the electrode current collector [0035]. On Example 1, the second negative electrode slurry was prepared mixing a negative electrode active material, silicon-based oxide (SiO), carbon black as a conductive material, styrene-butadiene rubber (SBR) as a second binder and CMC as a thickener in a ratio 96:4:1.5:1.6:1.1 [0072]. From Example 1, the styrene-butadiene rubber (SBR) employed amount was (1.6/104.2) x100= 1.54 wt.%.
Regarding claim 6, Nam teaches all the elements of the current invention in claim 1. From claim 1 discussion the feature “wherein the silicon oxide includes SiOx (0<x<2)” is met.
Regarding claim 7, Nam teaches all the elements of the current invention in claim 1. Based on Example 1 [0071 and 0072], the content of the silicon-based active material based on a total weight of the anode active material layer was (6/209.3)x100= 2.87 wt.%.
Regarding claim 9, Nam teaches all the elements of the current invention in claim 1. From claim 1 discussion the feature “wherein the second anode active material layer further includes a carbon-based active material” is met.
Regarding claim 10, Nam teaches all the elements of the current invention in claim 9. Nam further teaches that the carbon-based material may include at least one selected from the group consisting of artificial graphite, natural graphite, hard carbon, soft carbon, carbon black, acetylene black, Ketjen black, Super-P, graphene and fibrous carbon [0009].
Regarding claim 11, Nam teaches all the elements of the current invention in claim 1. Nam further teaches that when two sequentially stacked electrode active material layers (first and second anode active material layers) are formed, the first electrode active material layer is closer to the electrode current collector and is adjacent to the second electrode active material layer [0035]. From Figure 2, electrode active material slurry layers (120 and 130) represents the first and second anode active material layer, from which the feature “wherein the first anode active material layer is in contact with the surface of the anode current collector, and the second anode active material layer is in contact with a top surface of the first anode active material layer” [0042].
Regarding claim 12, Nam teaches all the elements of the current invention in claim 1. Nam further teaches a lithium secondary battery including: an electrode assembly including a positive electrode, a negative electrode including the multilayer electrode (claim 1), and a separator interposed between the positive electrode and the negative electrode (cathode facing the anode); a non-aqueous electrolyte for impregnating the electrode assembly [0018].
Claim 8 is rejected under 35 U.S.C. 103 as being unpatentable over Nam, Y. (EP 3591749 A1) as applied to claim 1 above, further in view of Sung et al. (KR 20200055448 a, see machine translation for citation).
Regarding claim 8, Nam teaches all the elements of the current invention in claim 1, except “wherein a content of the silicon-based active material based on a total weight of the anode active material layer is in a range from 4 wt.% to 15 wt.%”.
Sung teaches a lithium secondary battery comprising a negative electrode having a multilayer structure comprising a silicon-based compound [0001]. The negative electrode comprises a first negative active material layer formed on at least one surface of the above negative current collector and comprising, as a first negative active material, a mixture of graphite and a silicon-based compound mixed in a weight ratio of 95 to 99: 1 to 5 and a second negative electrode active material layer located on the first negative electrode active material layer and comprising, as a second negative electrode active material, a mixture of graphite and a silicon-based compound mixed in a weight ratio of 95 to 99: 1 to 5 [0028 and 0029]. The taught silicon-based compound may be a composite of Si and a carbonaceous material (Si-C composite), a composite formed by alloying Si and a metal, a carbon-Si nanocomposite and/ or a Si oxide [0042]. A binder may be included in each negative electrode active material layer in an amount of 1% to 30% by weight based on the total weight of the negative electrode active material layer [0057]. A conductive material is included in each negative electrode active material layer in an amount of 1% to 20% by weight based on the total weight of the negative electrode active material layer [claim 11].
From the above teachings, the negative electrode of Sung may comprise an active material amount between 50-98 wt.% on each respective layer. Since the graphite: silicon-based compound weight ratio is 95-99: 1-5 on each individual layer, the silicon-based compound amount per layer would be between 0.5-4.9 wt.%. Considering both layers, the total amount range of the silicon-based compound on the anode material would be 1-9.8 wt.%.
Sung is analogous art to the current invention because it is concerned with the same field of endeavor, namely an anode for a lithium secondary battery, comprising: an anode current collector; and an anode active material layer comprising a first anode active material layer and a second anode active material layer sequentially disposed on a surface of the anode current collector, each of the first anode active material layer and the second anode active material layer including a silicon-based active material, where the silicon-based active material includes at least one selected from the group consisting of a silicon alloy, a silicon oxide, a silicon-carbon (Si-C) composite and a silicon alloy-based carbon composite.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to have selected the overlapping portion of the total amount range of the silicon-based compound on the anode material calculated from Sung teachings, because overlapping ranges have been held to be a prima facie case of obvious. 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.
Conclusion
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/G.R./Examiner, Art Unit 1725
/JAMES M ERWIN/Primary Examiner, Art Unit 1725 04/09/2026
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