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 8/18/2026. Claims 1, 3-13 are pending. Claim 1 has been amended. Applicant’s arguments have been considered. Claims 1, 3-13 are finally rejected for reasons stated herein below.
Claim Rejections - 35 USC § 103
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.
Claims 1, 3-13 are rejected under 35 U.S.C. 103 as being unpatentable over Kim (US 2020/0243848, herein referred to as Kim ’848) in view of Kim (WO 2019/194662, herein referred to Kim ‘662, using US 2021/0020907 as translation).
Regarding claim 1, Kim ’848 discloses a negative electrode comprising: a negative electrode current collector; a first negative electrode active material layer disposed on the negative electrode current collector; and a second negative electrode active material layer disposed on the first negative electrode active material layer, wherein:
the second negative electrode active material layer includes a second negative electrode active material and a second conductive material [0031]; and
the second negative electrode active material includes a silicon-based active material and a carbon-based active material [0033], wherein:
the silicon-based active material includes SiOx (O<X<2) [0055]; and
the second conductive material includes: a carbon nanotube structure [0035], and
a particulate conductive material in the second negative electrode active material layer [0100].
Regarding claim 9, the particulate conductive material comprises carbon black [0033].
Regarding claim 11, the first negative electrode active material layer comprises a first negative electrode active material and a first conductive material, wherein the first conductive material includes at least one selected from the group consisting of the carbon nanotube structure, a multi-walled carbon nanotube unit, graphene, and carbon black [0104].
Regarding claim 12, a ratio of the thickness of the first negative electrode active material layer and the thickness of the second negative electrode active material layer is 1:1 to 1:2 [0102].
Regarding claim 10, an average particle diameter (D50) of the particulate conductive material is 0.1 um to 100 um, Kim ’848 discloses carbon black which has been used widely as a conductive material to date has a spherical shape, aggregates to fill the pores of active material particles therewith and is present in the form of a bridge in a space between active material particles in a spot contact mode, thereby forming a conductive path. In the case of an active material, such as a carbonaceous active material, showing little change in volume, such a conductive path formed by the bridge in a spot contact mode is retained stably. Thus, such an active material can realize an excellent effect as a conductive material [0036]. It would have been obvious to one of ordinary skilled in the art at the time the invention was made to adjust the particle diameter of the carbon black depending on the pore size of the second negative active material layer, for the benefit of forming a bridge to fill the pores to make conductive paths.
Regarding claim 1, Kim ‘848 discloses the second conductive material includes: a carbon nanotube structure, but does not disclose a carbon nanotube structure in which a plurality of single-walled carbon nanotube units are coupled side by side. Kim ‘907 teaches a carbon nanotube structure included in the electrode of the present invention, since the carbon nanotube structure is in the form in which 2 to 5,000 single-walled carbon nanotube units maintaining relatively high crystallinity without structural defects are bonded together side by side, the single-walled carbon nanotube units may not be cut even during the operation of the battery and their length may be smoothly maintained. Thus, the conductivity of the electrode may be maintained. Also, since the conductivity of the electrode is increased due to high conductivity of the single-walled carbon nanotube unit having high crystallinity, the input characteristics, output characteristics, and life characteristics of the battery may be significantly improved. Furthermore, since the carbon nanotube structures are interconnected in the electrode to have a network structure, an excessive change in the volume of the electrode active material may be suppressed, a strong conductive path may be secured at the same time, and electrode adhesion may be significantly improved by inhibiting deintercalation of the electrode active material [0046]. Regarding claim 3, Kim ‘907 teaches in the second negative electrode active material layer, the carbon nanotube structures are connected to each other to represent a network structure. Regarding claim 4, in the carbon nanotube structure, the single-walled carbon nanotube units are coupled in a state in which long axes of the single-walled carbon nanotube units are arranged parallel to each other [0046].
It would have been obvious to one or ordinary skilled in the art at the time the invention was made to use a bunded structure of carbon nanotubes, as taught by Kim ‘907, as the carbon nanotubes of Kim ‘848 for the benefit of strengthening the carbon nanotubes and increasing the conductivity, thus preventing structural defects on the carbon nanotubes.
Regarding claim 1, the carbon nanotube structure is included in the second negative electrode active material layer in an amount of an 0.005 wt% to 0.03 wt%, Kim ‘848 discloses carbon nanotubes may be used in an amount of 0.1-2 wt% based on the total weight of the negative electrode active material layer [0052]. When the content of carbon nanotubes satisfies the above-defined range, it is possible to retain conductivity between the silicon-based active materials during the shrinking of the silicon-based active material and to improve the binding ability of the negative electrode active material. Thus, it is possible to improve cycle characteristics of a lithium secondary battery [0054].
Kim ‘907 teaches the carbon nanotube structure may be included in an amount of 0.01 wt % to 0.5 wt % in the electrode active material layer, and may specifically be included in an amount of 0.02 wt % to 0.2 wt %. When the amount of the carbon nanotube structure satisfies the above range, since the conductive path in the electrode may be secured, the life characteristics of the battery may be improved while electrode resistance is maintained at a low level [0052]. It is noted that the endpoint of 0.02 wt% of Kim ‘907 meets Applicant’s limitation “in an amount of an 0.005 wt% to 0.03 wt%”.
It would have been obvious to one or ordinary skilled in the art at the time the invention was made to reduce the amount of singled walled carbon nanotube units bonded to each other side by side of Kim ‘907 from the carbon nanotubes of Kim ‘848, as taught by Kim ‘907, since the carbon nanotubes of Kim ‘907 are more conductive than the carbon nanotubes of Kim ‘848.
Regarding claim 1, a weight ratio of the carbon nanotube structure and the particulate conductive material is 12.7:87.3 to 0.5:99.5, Kim ‘848 discloses in Example 1 a mixture containing carbon black and carbon nanotubes at a ratio of 1:0.5 as a conductive material [0100]. Kim ‘907 teaches since an electrode prepared by using a conductive agent dispersion in which bundle-type single-walled carbon nanotubes were appropriately dispersed with polyvinylidene fluoride, carbon nanotube structures in the form of a rope (long fiber form) are interconnected in the electrode to form a network structure. Particularly, since the network structure may be formed to enable conductive connection between electrode active materials in the form of a secondary particle (relatively long distance) as well as conductive connection between primary particles in the electrode active material, a conductive path may be effectively formed in the electrode. Accordingly, electrical conductivity in the electrode may be significantly improved even with a very small amount of the conductive agent. Also, since an electrode active material layer is firmly fixed by the carbon nanotube structures constituting the network structure, an effect of improving electrode adhesion is achieved [0014].
It would have been obvious to one of ordinary skilled in the art at the time the invention was made to reduce the amount of carbon nanotubes of Kim ‘848, as taught by Kim ‘907, since carbon nanotubes bonded side by side that are easily dispersed of Kim ‘907 tend to be more conductive than carbon nanotubes without dispersion of Kim ‘848.
Regarding claim 5, an average length of the carbon nanotube structure is 3 um to 15 um, Kim ‘907 teaches in the carbon nanotube structure, the single-walled carbon nanotube unit may have an average length of 1 μm to 100 μm, for example, 5 μm to 50 μm. When the average length is satisfied, since a long conductive path for conductive connection between the electrode active materials may be formed and a unique network structure may be formed, the conductivity in the electrode may be maximized even with a very small amount of the conductive agent [0048]. It would have been obvious to one or ordinary skilled in the art at the time the invention was made to adjust the length of the carbon nanotube structure, as taught by Kim ‘907, for the benefit of maximizing the conductivity.
Regarding claim 6, an average diameter of the carbon nanotube structure is 2 nm to 500 nm, Kim ‘907 teaches the carbon nanotube structure may have an average diameter of 1 nm to 300 nm, for example, 3 nm to 150 nm. When the average diameter satisfies the above range, since it is effective in forming a conductive network structure and is advantageous in connecting the active materials, excellent electrical conductivity may be achieved [0050]. It would have been obvious to one or ordinary skilled in the art at the time the invention was made to adjust the average diameter of the carbon nanotube structure, as taught by Kim ‘907, for the benefit of maximizing the conductivity.
Regarding claim 7, in the carbon nanotube structure, an average diameter of the single-walled carbon nanotube units is 0.1 nm to 10 nm, Kim ‘907 teaches in the carbon nanotube structure, the single-walled carbon nanotube unit may have an average diameter of 0.5 nm to 10 nm, particularly 1 nm to 9 nm, and more particularly 1 nm to 6 nm. When the average diameter is satisfied, conductivity in the electrode may be maximized even with a very small amount of the conductive agent. It would have been obvious to one or ordinary skilled in the art at the time the invention was made to adjust the average diameter of the single-walled carbon nanotube unit, as taught by Kim ‘907, for the benefit of maximizing the conductivity.
Regarding claim 8, the carbon nanotube structure has a structure in which 2 to 50 single-walled carbon nanotube units are coupled to each other, Kim ‘907 teaches in contrast, the carbon nanotube structure included in the electrode of the present invention is in the form in which 2 to 5,000 single-walled carbon nanotube units are bonded together side by side. Thus, since the single-walled carbon nanotube units may not be cut even during the operation of the battery and their length may be smoothly maintained, the conductivity of the electrode may be maintained and the conductivity of the electrode may be smoothly secured due to the high conductivity of the single-walled carbon nanotube unit. Accordingly, the input characteristics, output characteristics, and life characteristics of the battery may be excellent even if the amount of the carbon nanotube structure in the electrode is low [0054]. It would have been obvious to one or ordinary skilled in the art at the time the invention was made to adjust the number of units of the carbon nanotube structure, as taught by Kim ‘907, for the benefit of maximizing the conductivity.
Regarding claim 13, Kim ‘848 modified by Kim ‘907 teaches a secondary battery comprising the negative electrode of claim 1.
Response to Arguments
Arguments dated 8/18/2026 are addressed below:
Applicant asserts Kim'848 specifically teaches replacing carbon black with carbon nanotubes. Kim'848 teaches that carbon nanotubes are sufficiently positioned over an entire surface of a silicon based active material to maintain an excellent conductive path. To achieve such coverage, Kim'848 teaches that it is necessary to include a large wt% of carbon nanotubes (0.5 wt% or 0.3 wt%) in a second negative electrode active material layer. (See Kim'848 at [0041] and FIG. 4). Kim'848 does not teach using carbon black in combination with carbon nanotubes nor does Kim'848 teach reducing an amount of carbon nanotubes. In contrast, the claimed invention recites a much smaller wt% of the carbon nanotube structure of "0.005 wt% to 0.03 wt%." One of ordinary skill in the art would not have been motivated to reduce the wt% of carbon nanotubes taught in Kim'848, as Kim'848 teaches that a large wt% of carbon nanotubes is needed to realize excellent lifetime characteristics.
Secondary reference Kim'907 does not remedy this deficiency of Kim'848. Kim'907 teaches that conventional point type conductive materials such as carbon black do not provide a sufficient effect of improving electrical conductivity. (See Kim'907 at [0005]). Comparative Example 1 of Kim'907, including carbon black, results in reduced adhesion and lifetime characteristics over Examples 1-3 of Kim'907, including carbon nanotube structures.
Further, Kim'907 teaches a positive electrode active material containing polyvinylidene fluoride and a dispersion medium including organic solvents such as NMP. (See Kim'907 at [0011], [0056], [0074]). The Action has not provided sufficient rationale as to why one of ordinary skill in the art would be motivated to combine Kim'907 with Kim'848, when Kim'848 teaches a negative electrode including styrene-butadiene rubber (SBR) and carboxymethyl cellulose (CMC) and water as a dispersion medium. (See Kim'848 at [0099]). Thus, in view of the completely different compositions of Kim'907 and Kim'848, and because the electrode active material art is highly unpredictable, Applicant respectfully submits that a person of ordinary skill in the art would not have been motivated to combine Kim'907and Kim'848 to arrive at the claimed invention. Page 5 of Arguments.
In response to applicant's arguments against the references individually, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986). Applicant is referred to Kim ‘907 for the amount of carbon nanotubes, and not Kim ‘848.
Regarding claim 1, a weight ratio of the carbon nanotube structure and the particulate conductive material is 12.7:87.3 to 0.5:99.5, Kim ‘848 discloses in Example 1 a mixture containing carbon black and carbon nanotubes at a ratio of 1:0.5 as a conductive material [0100]. Kim ‘907 teaches since an electrode prepared by using a conductive agent dispersion in which bundle-type single-walled carbon nanotubes were appropriately dispersed with polyvinylidene fluoride, carbon nanotube structures in the form of a rope (long fiber form) are interconnected in the electrode to form a network structure. Particularly, since the network structure may be formed to enable conductive connection between electrode active materials in the form of a secondary particle (relatively long distance) as well as conductive connection between primary particles in the electrode active material, a conductive path may be effectively formed in the electrode. Accordingly, electrical conductivity in the electrode may be significantly improved even with a very small amount of the conductive agent. Also, since an electrode active material layer is firmly fixed by the carbon nanotube structures constituting the network structure, an effect of improving electrode adhesion is achieved [0014].
It would have been obvious to one of ordinary skilled in the art at the time the invention was made to reduce the amount of carbon nanotubes of Kim ‘848, as taught by Kim ‘907, since carbon nanotubes bonded side by side that are easily dispersed of Kim ‘907 tend to be more conductive than carbon nanotubes without dispersion of Kim ‘848.
Although the example of Kim ‘907 is direct to a positive electrode active material, Kim ‘907 further teaches that the electrode active material may be a positive or a negative electrode active material [0038].
Applicant asserts the cited art does not recognize the advantages of the claimed ratio relationship and wt% of the carbon nanotube structure as illustrated in the data of the present application. Kim'848 teaches a ratio of carbon nanotubes (not the carbon nanotube structure) to carbon black of 30-50 to 100-120 (25-50%). In contrast, the claimed invention recites a ratio of the carbon nanotube structure to carbon black of 0.5-12.7 to 87.3-99.5 (0.5-14.5%). Example 1 of the present application teaches a ratio of 3 to 97, which is within the claimed range, as having a higher adhesion force and improved initial degradation and long-term lifespan properties over Comparative Example 2 having a ratio of 0.272 to 99.73, which is outside of the claimed range.
While Kim'907 does teach that a smaller amount of the claimed carbon nanotube structure (0.01 to 0.5 wt%) is required to be effective, Kim'907 is silent in regards to the addition of a particulate conductive material such as carbon black. As discussed above, Kim'907 teaches using the claimed carbon nanotube structure instead of carbon black as a conductive material. (See Comparative Example 1 of Kim'907). Further, Example 3 of Kim'907, which teaches a 0.05 wt% of the carbon nanotube structure, is a value obtained in a NCM622 positive electrode not the claimed negative electrode including a silicon-based active material which undergoes substantial volume changes during charging and discharging. Accordingly, it would not have been obvious to combine Kim'848 with Kim'907 to arrive at the claimed weight ratio of carbon nanotube structures to particulate conductive material and the claimed carbon nanotube structure wt% when there are innumerable options to vary. (See Ex parte Kraus, Appeal No. 2021-002347; see also SNF S.A. v. Solenis Technologies, IPR2020-01730, Paper 10 (Apr. 22, 2021)). Page 5-6 of Arguments.
In response to applicant's arguments against the references individually, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986). Applicant is referred to Kim ‘848 for carbon black, and not Kim ‘907.
Regarding the weight ratio of the carbon nanotube structure, Kim ‘848 discloses in Example 1 a mixture containing carbon black and carbon nanotubes at a ratio of 1:0.5 as a conductive material [0100]. Kim ‘907 teaches since an electrode prepared by using a conductive agent dispersion in which bundle-type single-walled carbon nanotubes were appropriately dispersed with polyvinylidene fluoride, carbon nanotube structures in the form of a rope (long fiber form) are interconnected in the electrode to form a network structure. Particularly, since the network structure may be formed to enable conductive connection between electrode active materials in the form of a secondary particle (relatively long distance) as well as conductive connection between primary particles in the electrode active material, a conductive path may be effectively formed in the electrode. Accordingly, electrical conductivity in the electrode may be significantly improved even with a very small amount of the conductive agent. Also, since an electrode active material layer is firmly fixed by the carbon nanotube structures constituting the network structure, an effect of improving electrode adhesion is achieved [0014].
It would have been obvious to one of ordinary skilled in the art at the time the invention was made to reduce the amount of carbon nanotubes of Kim ‘848, as taught by Kim ‘907, since carbon nanotubes bonded side by side that are easily dispersed of Kim ‘907 tend to be more conductive than carbon nanotubes without dispersion of Kim ‘848.
Although the example of Kim ‘907 is direct to a positive electrode active material, Kim ‘907 further teaches that the electrode active material may be a positive or a negative electrode active material [0038].
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). 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, Jonathan Leong can be reached at 571-270-1292. 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
