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 .
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 07/30/2025 has been entered.
Response to Amendment
The declaration under 37 CFR 1.132 filed 07/30/2025 is insufficient to overcome the rejection of claim 1 based upon 35 U.S.C 103 (see Response to Arguments below).
Response to Arguments
Applicant's arguments filed 07/30/2025 have been fully considered but they are not persuasive.
Applicant argues (p. 5-7) that Zettsu is silent as to the average length of the elongated second carbon material corresponding to the carbon nanotube structure of the claimed invention. Zettsu FIG. 2 would lead one of ordinary skill in the art to understand that the second carbon material should have a length shorter than the diameter of the active material particles. In Example embodiments, Zettsu teaches wherein the elongated second carbon material has an average length of 7 µm. Therefore, Zettsu fails to teach or suggest carbon nanotube structures having an average length of “10 µm to 70 µm” as required by amended claim 1.
The Examiner respectfully disagrees, as Zettsu teaches an overlapping range of 2 µm to 10 µm ([0057]) and that the elongated second carbon material should be long enough to improve electrical conductivity without reducing dispersibility ([0056]) so that the elongated carbon material can connect active secondary active material particles ([0096]), including those not directly adjacent to one another ([0101]).
Applicant argues (p. 8-9) that the data in the attached Declaration show that there is no motivation to arrive at the claimed invention, wherein the carbon nanotube structure has an average length of 10 µm to 70 µm, with a reasonable expectation of success. The secondary battery of Additional Comparative Example 1, which included an electrode containing a carbon nanotube structure having an average length lower than the claimed range exhibited degraded characteristics due to insufficient formation of a conductive network between active material particles caused by the short average length of the carbon nanotube structure. The secondary battery of Additional Comparative Example 2, which included an electrode containing a carbon nanotube structure having an average length higher than the claimed range also exhibited degraded characteristics because the large average length of the carbon nanotube structure prevented the inclusion of enough conductive agents to form a conductive network. Both Additional Comparative Examples used the commercially available bundled carbon nanotube product used in the examples disclosed by Zettsu. The material properties of the raw commercially available nanotubes, including the diameter, length, degree of crystallinity, and surface functional groups are entirely different from those of the claimed carbon nanostructure. Therefore, it is unlikely that one of ordinary skill in the art could arrive at the claimed nanotube structure.
The Examiner respectfully disagrees. Regarding the Additional Comparative Examples including carbon nanotube structures having lengths outside the claimed range, the results shown appear to require additional limitations including specific active material particles, multi-walled carbon nanotubes, and binder, which are not currently required by independent claim 1. Therefore, the independent claim does not appear to be commensurate in scope with the showing of evidence. Though Zettsu uses particular single-walled nanotubes in the Examples, the disclosure is not limited to said nanotubes and a skilled artisan could reasonably select the appropriate nanotubes to form the conductive structure described by Zettsu.
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 1-4, 10-12, and 14-17 are rejected under 35 U.S.C. 103 as being unpatentable over Zettsu (US 2021/0313559 A1; previously cited) as evidenced by Hersam (Progress towards monodisperse single-walled carbon nanotubes, 2008; cited 01/31/2025).
Regarding claim 1, Zettsu discloses an electrode comprising an electrode active material layer ([0046]), the electrode active material layer comprising an electrode active material ([0051]) and a conductive agent ([0053]), the conductive agent comprising: a multi-walled carbon nanotube unit (first elongated carbon material, [0058]); and a carbon nanotube structure (second elongated carbon material, [0058]; elongated second carbon nanotubes self-aggregate in a bundle form) in which 2 to 5,000 single-walled carbon nanotube units are bonded to each other (Hersam evidences that a carbon nanotube bundle comprises multiple single-walled carbon nanotube units bonded to each other Fig. 1a, P387 C2 ¶2; Zettsu therefore discloses an overlapping range of 2 or more single-walled carbon nanotube units), wherein, in the carbon nanotube structure, the single-walled carbon nanotube units are arranged side by side and bonded (bundle form, [0095]; Hersam evidences that a carbon nanotube bundle comprises multiple single-walled carbon nanotube units arranged side by side and bonded, Fig. 1a, P387 C2 ¶2), and wherein the carbon nanotube structure is contained in the electrode active material layer in an amount of 0.01 wt% to 0.5 wt% (“Content of second CNT,” Table 1 p. 8-9, [0106]).
Zettsu does not disclose wherein the carbon nanotube structure has an average length of 10 µm to 70 µm.
However, a person having ordinary skill in the art before the effective filing date of the invention would have found it obvious to have optimized the length of the carbon nanotube structure of Zettsu to 10 µm because Zettsu teaches an overlapping range of 2 µm to 10 µm ([0057]) and that the elongated second carbon material should be long enough to improve electrical conductivity without reducing dispersibility ([0056]) so that the elongated carbon material can connect active secondary active material particles ([0096]), including those not directly adjacent to one another ([0101]).
Regarding claim 2, Zettsu teaches wherein a weight ratio of the multi-walled carbon nanotube unit to the carbon nanotube structure is 100:1 to 100:200 (90-99:1-10, [0059]).
Regarding claim 3, Zettsu teaches wherein the multi-walled carbon nanotube unit is contained in the electrode active material layer in an amount of 0.1 wt% to 1.0 wt% (0.425 wt% to 0.99 wt%, “Content of first CNT,” Table 1, p. 8-9).
Regarding claim 4, Zettsu teaches wherein multiple carbon nanotube structures are connected to each other to represent a network structure in the electrode ([0096], FIG. 2).
Regarding claim 10, Zettsu teaches wherein, in the carbon nanotube structure, the single-walled carbon nanotube unit has an average diameter of 0.5 nm to 5 nm (1 nm to 5 nm, [0057]).
Regarding claim 11, Zettsu teaches wherein the multi-walled carbon nanotube unit has an average diameter of 5 nm to 200 nm (overlapping range of 10 nm to 400 nm, [0057], establishes a prima facie case of obviousness [MPEP § 2144.05(I)]).
Regarding claim 12, Zettsu teaches wherein the multi-walled carbon nanotube unit has an average length of 0.1 µm to 100 µm (2 µm to 10 µm, [0057]).
Regarding claim 14, Zettsu teaches wherein the electrode is a positive electrode ([0046]).
Regarding claim 15, Zettsu teaches a secondary battery comprising the electrode of claim 1, a separator, and an electrolyte ([0086]).
Regarding claim 16, Zettsu teaches wherein the carbon nanotube structure is a cylindrical structure in which a plurality of the single-walled carbon nanotube units are bonded in parallel with each other along long axes of the single-walled carbon nanotube units (bundle, [0095]; Hersam evidences that a carbon nanotube bundle comprises multiple single-walled carbon nanotube units bonded in parallel with each other along long axes of the single-walled carbon nanotube units, Fig. 1a, P387 C2 ¶2).
Regarding claim 17, Zettsu teaches wherein the single-walled carbon nanotube units of the carbon nanotube structure are bonded in parallel with each other in a single plane (bundle, [0095]; Hersam evidences that a carbon nanotube bundle comprises multiple single-walled carbon nanotube units bonded in parallel with each other in a single plane, Fig. 1a, P387 C2 ¶2).
Claims 8 and 9 are rejected under 35 U.S.C. 103 as being unpatentable over Zettsu as evidenced by Hersam, as applied to claim 1 above, and further in view of Ma (US 2014/0332731 A1; previously cited).
Regarding claim 8, Zettsu in view of Ponnamma does not disclose wherein the carbon nanotube structure has an average diameter of 2 nm to 200 nm.
Ma teaches an electrode comprising an electrode active material layer, the electrode active material layer comprising an electrode active material and a conductive agent, the conductive agent comprising carbon nanotubes ([0010]), wherein the diameter of the carbon nanotubes is related to the size of the active material particles ([0010]-[0011]). A person having ordinary skill in the art before the effective filing date of the invention would have found it obvious to have optimized the average diameter of the carbon nanotube structure of Zettsu, including to a range corresponding to 2 nm to 200 nm, so that the carbon nanotube structure is large enough to fill gaps between large active material particles but not so large as to reduce the capacity of the battery as taught by Ma ([0010]-[0011]).
Regarding claim 9, Zettsu in view of Ponnamma does not disclose wherein the carbon nanotube structure has an average diameter of 50 nm to 120 nm.
Ma teaches an electrode comprising an electrode active material layer, the electrode active material layer comprising an electrode active material and a conductive agent, the conductive agent comprising carbon nanotubes ([0010]), wherein the diameter of the carbon nanotubes is related to the size of the active material particles ([0010]-[0011]). A person having ordinary skill in the art before the effective filing date of the invention would have found it obvious to have optimized the average diameter of the carbon nanotube structure of Zettsu, including to a range corresponding to 50 nm to 120 nm, so that the carbon nanotube structure is large enough to fill gaps between large active material particles but not so large as to reduce the capacity of the battery as taught by Ma ([0010]-[0011]).
Claim 13 is rejected under 35 U.S.C. 103 as being unpatentable over Zettsu as evidenced by Hersam, as applied to claim 1 above, and further in view of Ponnamma (Carbon nanotube based elastomer composites–an approach towards multifunctional materials, 2014; cited 05/21/2024).
Regarding claim 13, Zettsu does not wherein the carbon nanotube structure is a carbon nanotube structure in which 50 to 4,000 single-walled carbon nanotube units are bonded to each other.
Ponnamma teaches carbon nanotube structures in which single-walled carbon nanotube units are bonded to each other and that the number of units in a structure is related to the alignment and agglomeration of the structure (sec. 3.2, lines 24-30). Therefore, it would have been a matter of routine experimentation for a person having ordinary skill in the art before the effective filing date of the invention to have optimized the number of units, e.g., between 2 and 5000, constituting the carbon nanotube structure of Zettsu to achieve regular alignment without excessive agglomeration based on the relationship Ponnamma establishes between bundle size and alignment (sec. 3.2, lines 24-30).
Conclusion
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/C.C.D./Examiner, Art Unit 1723 /TIFFANY LEGETTE/Supervisory Patent Examiner, Art Unit 1723