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 . If status of the application as subject to 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 a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
Status of Claims
Claims 1-3 & 6 were rejected in the office action mailed 12/10/2025. Claims 1-3 & 6 are pending in the application and are presently examined.
Response to Amendment / Arguments
The amendment filed 3/6/2026, in response to the 12/10/2025 office action, has been entered. Applicant’s claim amendments overcame all objections. Applicant’s claim amendments and arguments, regarding the 35 U.S.C. 103 rejections, have been fully considered but they are not persuasive.
As discussed in the prior office action, US20180183055A1 (Chang) teaches VGCF and carbon nanotubes as optional materials in a negative electrode (paragraph 26). Applicant argues:
“However, Chang describes… the equivalence of VGCF and carbon nanotubes for a negative electrode active material. However, Chang fails to describe the equivalence of VGCF and carbon nanotubes for a conductive material.”
Examiner agrees that Chang fails to explicitly state that these materials are conductive, probably because the conductivity of these materials was well known1,2, so it was obvious. Regardless of lack of discussion on conductivity of these materials, Chang teaches them as alternative negative electrode materials, and claim 1 is for a negative electrode; therefore, it would have been obvious to substitute one for the other in a negative electrode.
Applicant amended claim 1 to require “an aspect ratio of 20000 or more”. As discussed in the prior office action, US20190044133A1 (Burshtain) teaches 150 to 10,000 aspect ratios. MPEP 2144.05 (I) provides the law for this issue:
“Similarly, a prima facie case of obviousness exists where the claimed ranges or amounts do not overlap with the prior art but are merely close. Titanium Metals Corp. of America v. Banner, 778 F.2d 775, 783, 227 USPQ 773, 779 (Fed. Cir. 1985)… ‘The proportions are so close that prima facie one skilled in the art would have expected them to have the same properties.’”
Applicant must provide evidence that the claimed range is not obvious over Burshtain’s range. The present specification, however, indicates that the upper end of Burshtain’s range is equivalent to the claimed range. The present specification states:
“[0025] Also, the aspect ratio… of the CNTs is 5000 or more, and preferably 10000 or more. When the CNTs satisfy the fiber diameter and the aspect ratio within the above described ranges, a favorable three-dimensional conductive network can be formed in the molded body of the negative electrode material mixture, and favorable conductivity is obtained in the molded body… However, the upper limit value of the aspect ratio of the CNTs is normally about 200000, and preferably 50000 or less.”
Thus, according to the present specification, all aspect ratios ≥ 5000 are effective and approximately equivalent. Based on MPEP 2144.05 (I) and paragraph 25 of the present specification, the claimed aspect ratio of ≥ 20,000 is obvious over Burshtain’s 150 to 10,000 aspect ratios.
Evidence of unexpected results can overcome a 35 U.S.C. 103 rejection. According to MPEP 716.02(d), such “evidence of nonobviousness must be commensurate in scope with the claims”. The present specification provides evidence of nonobviousness only for aspect ratio = 20,000 (Specification pp. 25 & 28), but not for aspect ratio ≥ 20,000.
Applicant’s Comparative Examples have aspect ratios of 60-4500. Thus, it seems that an aspect ratio = 20,000 is better than aspect ratios of 60-4500. Burshtain’s range includes a 5000 to 10,000 aspect ratio range. There is no evidence that the claimed aspect ratio ≥ 20,000 is superior to a 5000 to 10,000 aspect ratio range.
Furthermore, the ≥ 20,000 aspect ratio claim limitation is also rejected below based on newly-cited prior art, which teaches a range that overlaps the claimed range.
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.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
Determining the scope and contents of the prior art.
Ascertaining the differences between the prior art and the claims at issue.
Resolving the level of ordinary skill in the pertinent art.
Considering objective evidence present in the application indicating obviousness or nonobviousness.
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.
The claims are in bold font, the prior art is in parentheses.
Claims 1-3 & 6 are rejected under 35 U.S.C. 103 as being unpatentable over US20200044284A1 (Fujino) in view of US20180183055A1 (Chang), US20190044133A1 (Burshtain), and US20020061441A1 (Ogura) together “modified Fujino”.
With regard to claim 1, Fujino teaches the following claim limitations:
A negative electrode (paragraph 37; figure 1: anode layer 2) for an all-solid state secondary battery (paragraphs 37 & 92) comprising a negative electrode active material (paragraphs 37, 42, & 116: anode layer 2 contains Si-based active material), a conductive aid (paragraph 42: second conductive material), and a sulfide-based solid electrolyte (paragraph 116: anode includes a sulfide solid electrolyte), wherein the negative electrode contains carbon nanotubes as the conductive aid (paragraph 50: the second conductive material can be carbon nanotubes)
Fujino’s example 1 (paragraph 116), with the sulfide solid electrolyte, has vapor-grown carbon fiber (VGCF) as a conductive material. Fujino teaches carbon nanotubes (paragraphs 42 & 50) as the conductive material in a different part of the publication. Fujino fails to provide an example of the sulfide solid electrolyte combined with the carbon nanotubes in the anode layer 2.
Chang teaches VGCF and carbon nanotubes as optional materials in a negative electrode (paragraph 26). Chang thus recognizes the equivalency of VGCF and carbon nanotubes for a negative electrode material. Therefore, it would have been obvious to one of ordinary skill in the art, before the effective filing date of the invention, to replace the VGCF of Fujino’s example 1 (paragraph 116) with carbon nanotubes taught by Chang (paragraph 26) and Fujino (paragraph 42 & 50). This replacement is merely the selection of functionally equivalent negative electrode materials recognized in the art. One of ordinary skill in the art would have a reasonable expectation of success in making this replacement.
Fujino fails to teach the following carbon nanotube dimensions, which are taught by Burshtain:
carbon nanotubes… have a fiber diameter of 0.8 to 20 nm (paragraph 197: carbon nanotube diameter = 10-20 nm)
Claim 1 also recites:
the negative electrode contains carbon nanotubes that have… an aspect ratio of 20000 or more
Burshtain teaches carbon nanotube length: 3 to 100 μm (paragraph 197). Combining Burshtain’s carbon nanotube diameter (paragraph 197: 10-20 nm) with length (paragraph 197: 3 to 100 μm), Burshtain’s carbon nanotube aspect ratios are 150 to 10,000:
3000
n
m
20
n
m
=
150
100,000
n
m
10
n
m
=
10,000
Therefore, Burshtain’s 150 to 10,000 range is near the claimed range of ≥ 20,000. MPEP 2144.05 (I) provides the law for this issue:
“Similarly, a prima facie case of obviousness exists where the claimed ranges or amounts do not overlap with the prior art but are merely close. Titanium Metals Corp. of America v. Banner, 778 F.2d 775, 783, 227 USPQ 773, 779 (Fed. Cir. 1985)… ‘The proportions are so close that prima facie one skilled in the art would have expected them to have the same properties.’”
Given that there is only a small difference in ranges, and further given the fact that no criticality is disclosed for the claimed range compared to the upper half of Burshtain’s range, the claimed range is an obvious variant of Burshtain’s range.
Burshtain is directed to improved anodes that enable fast charging rates with enhanced safety (abstract). It would have been obvious, to one of ordinary skill in the art, before the effective filing date of the invention, for Fujino’s carbon nanotubes to have a 10-20 nm diameter and 150 to 10,000 aspect ratios as part of an improved anode that enables fast charging rates with enhanced safety.
Ogura provides added guidance. Ogura describes an electrode with carbon nanotubes that have a 3.5 to 200 nanometer diameter and a 0.1 to 500 micrometer length (100 nm to 500,000 nm). Thus, Ogura’s aspect ratio range is 100nm/200nm to 500,000nm/3.5nm = 0.5 to 142,857.
Therefore, Ogura’s 0.5 to 142,857 range overlaps the claimed ≥ 20,000 range. MPEP 2144.05 (II)(A) provides the law for this issue:
“In the case where the claimed ranges ‘overlap or lie inside ranges disclosed by the prior art’ a prima facie case of obviousness exists. In re Wertheim, 541 F.2d 257, 191 USPQ 90 (CCPA 1976)”
Given that Ogura’s range is similar to and substantially overlaps the claimed range, and further given the fact that no criticality is disclosed for the claimed range, the aspect ratio range in claim 1 is an obvious variant of Ogura’s range.
Ogura is directed to an electrode with an electrically conductive matrix (paragraph 11). It would have been obvious, to one of ordinary skill in the art, before the effective filing date of the invention, for modified Fujino’s carbon nanotubes to have a 0.5 to 142,857 aspect ratio, as taught by Ogura, for an electrode with an electrically conductive matrix.
With regard to claim 2, modified Fujino teaches the limitations of claim 1 as described above. Modified Fujino also teaches the following claim 2 limitation:
a molded body obtained by molding a negative electrode material mixture that contains the negative electrode active material, the conductive aid, and the sulfide-based solid electrolyte into a pellet (Fujino paragraphs 37, 42, 50, & 116: anode layer 2 includes active material, conductive material, and sulfide solid electrolyte mixed in a slurry, pasted on an anode current collector, then dried)
With regard to claim 3, modified Fujino teaches the limitations of claim 1 as described above. Claim 3 recites:
comprising hard carbon as the negative electrode active material
Fujino teaches hard carbon for the cathode (paragraph 80), but not for the anode. For the anode, Fujino teaches a first conductive material (paragraph 42) in addition to the second conductive material / carbon nanotubes (paragraphs 42 & 50).
Burshtain teaches hard carbon for the anode conductive material (paragraph 189). Burshtain is directed to improved anodes that enable fast charging rates with enhanced safety (abstract). It would have been obvious, to one of ordinary skill in the art, before the effective filing date of the invention, for Fujino’s first conductive material to be hard carbon, as taught by Burshtain, as part of an improved anode that enables fast charging rates with enhanced safety.
With regard to claim 6, Fujino teaches the following claim limitations:
An all-solid-state secondary battery (paragraphs 37 & 92: solid state battery 10) comprising a positive electrode (paragraph 37; figure 1A: cathode layer 1), a negative electrode (paragraph 37; figure 1A: anode layer 2), and a sulfide-based solid electrolyte layer (paragraphs 37 & 120; figure 1A: solid electrolyte layer 3) between the positive electrode (1) and the negative electrode (2), wherein the all-solid-state secondary battery (10) includes the negative electrode for the all-solid-state secondary battery according to claim 1 as the negative electrode (see discussion under claim 1 above)
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 extension fee 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 date of this final action.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ROBERT WEST whose telephone number is 703-756-1363 and email address is Robert.West@uspto.gov. The examiner can normally be reached Monday-Friday 10 am - 7 pm ET.
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/R.G.W./Examiner, Art Unit 1721
/ALLISON BOURKE/Supervisory Patent Examiner, Art Unit 1721
1 https://link.springer.com/article/10.1557/JMR.2001.0231
2 https://link.springer.com/rwe/10.1007/978-3-319-70614-6_51-1