DETAILED ACTION
Notice to Applicant
In the amendment dated 2026-06-04, the following has occurred: Claim 1 has been amended; Claims 3-6 have been canceled.
Claims 1-2 and 7-13 are pending and are examined herein. This is a Final Rejection.
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(d):
(d) REFERENCE IN DEPENDENT FORMS.—Subject to subsection (e), a claim in dependent form shall contain a reference to a claim previously set forth and then specify a further limitation of the subject matter claimed. A claim in dependent form shall be construed to incorporate by reference all the limitations of the claim to which it refers.
The following is a quotation of pre-AIA 35 U.S.C. 112, fourth paragraph:
Subject to the following paragraph [i.e., the fifth paragraph of pre-AIA 35 U.S.C. 112], a claim in dependent form shall contain a reference to a claim previously set forth and then specify a further limitation of the subject matter claimed. A claim in dependent form shall be construed to incorporate by reference all the limitations of the claim to which it refers.
Claim 2 is rejected under 35 U.S.C. 112(d) as being of improper dependent form for failing to further limit the subject matter of the claim upon which it depends, or for failing to include all the limitations of the claim upon which it depends. Claim 2 does not further delimit the amended claim 1. Applicant may cancel the claim(s), amend the claim(s) to place the claim(s) in proper dependent form, rewrite the claim(s) in independent form, or present a sufficient showing that the dependent claim(s) complies with the statutory requirements.
Claim Rejections - 35 USC § 103
Claims 1-2, 7-10 and 12 are rejected under 35 U.S.C. 103 as being unpatentable over Son (US 2017/0104209 to Son et al.).
Regarding Claims 1 and 2, Son teaches:
a negative electrode for a lithium secondary battery comprising a three-dimensional, porous carbon paper coated with a PVDF-HFP copolymer (¶ 0157-0158 and 0165)
the porous carbon paper being a commercially available paper with a thickness of 100 microns and having 90% porosity (¶ 0158) wherein the paper is covered with a layer 5 microns thick of PVDF-HFP (¶ 0165), and wherein the thickness of the protective layer can vary up to 50 microns, or more preferably, 10 microns (¶ 0132)
wherein the protective fluorinated polymer layer can be applied via conventional coating methods, such as dip coating, spray coating, spin coating, etc. (¶ 0133)
wherein lithium metal is applied to an outer surface and pressed into the coated carbon paper (¶ 0158, 0027)
PVDF-HFP copolymer typically has F/C ratios of 1.1-1.3. Assuming a carbon skeletal density of around 1.8-2 g/mL, a porosity of 90%, a PVDF-HPF density of around 1.8 g/mL, and a polymer layer of 5 microns (in the middle of the preferred range, with Son rendering obvious layers up to 10 microns, and therefore double the fluorine atoms of the subsequent calculation), the conservative range for fluorine atoms per 100 carbon atoms of the coated paper in Example 6 is perhaps 14-17 F/100C. This substantially overlaps the claimed range, and Son renders obvious slightly thicker layers at the same porous carbon paper thickness.
The claim limitations “wherein the three-dimensional carbon structure coated with the fluorine-based polymer is formed by coating the three-dimensional carbon structure with an aqueous solution […] the fluorine-based polymer is contained in an amount of 10% by weight or more and less than 20% by weight relative to the total weight of the aqueous solution” is interpreted as a product-by-process limitation. Product-by-process claims are not limited to the manipulations of the recited steps, only the structure implied by the steps. “[E]ven though product-by-process claims are limited by and defined by the process, determination of patentability is based on the product itself. The patentability of a product does not depend on its method of production. If the product in the product-by-process claim is the same as or obvious from a product of the prior art, the claim is unpatentable even though the prior product was made by a different process.” In re Thorpe, 777 F.2d 695, 698, 227 USPQ 964, 966 (Fed. Cir. 1985). See MPEP 2113 [R-1]. In the instant case, application via aqueous solutions of 6-8 wt% polymer are interpreted to produce substantially similar primer layers absent evidence that the claimed method step produces a materially different coating. The Office points out that the instant specification appears to indicate that aqueous polymer solutions of 2 wt% or more produce substantially similar layers as the claimed range, suggesting the claimed range does not produce a critical difference (¶ 0040 of PGPUB US 2023/0253556). Son renders obvious a range of conventional treatments in the art that would be expected to produce substantially similar layers absent evidence of unexpected results for the claimed method of production. Simple substitution of one known element for another to obtain predictable results has been found to be obvious. See KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007).
Regarding Claim 7, Son teaches:
laminating the foil and pressing it (¶ 0027)
Regarding Claims 8 and 9, Son teaches:
use of fluoropolymers in the anode, which is known to react to form LiF
See previously cited Wang2 (Wang et al. “Tuning wettability of molten lithium via a chemical strategy for lithium metal anodes.” Nature Communications (2019) 10:4930) and Shang (Shang et al. “Scalable Synthesis of LiF-rich 3D Architected Li Metal Anode via Direct Lithium-Fluoropolymer Pyrolysis to Enable Fast Li Cycling.” Energy Environ. Mater. 2021, 4, 213-221), which discuss formation of LiF at the anode. Son teaches substantially the same electrode as that presently claimed, and would therefore be expected to form LiF during cycling absent Applicant pointing to some critical positive structural difference.
Regarding Claim 10, Son teaches:
PVDF-HFP (¶ 0165)
Regarding Claim 12, Son teaches:
a battery with cathode, anode, and separator with electrolyte (see examples)
Regarding Claims 11 and 13, Son teaches:
conventional cathodes known in the art (¶ 0141)
Lithium-sulfur batteries were conventional in the art. Although Son does not explicitly teach a sulfur cathode, it would have been obvious to use a sulfur cathode in combination with the anode taught by Son, since sulfur cathodes were known substitutes for transition metal oxides as cathodes in the art, with their own predictable characteristics for cycling. Simple substitution of one known element for another to obtain predictable results has been found to be obvious. See KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398 (2007).
Response to Arguments
The Remarks filed 2026-06-04 have been considered but do not place the application in condition for allowance. In response to the claim amendments the rejections have been modified to rely on Son.
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 Michael Dignan, whose telephone number is (571) 272-6425. The examiner can normally be reached from Monday to Friday between 10 AM and 6:30 PM. If any attempt to reach the examiner by telephone is unsuccessful, the examiner’s supervisor, Tiffany Legette, can be reached at (571)270-7078. Another resource that is available to applicants is the Patent Application Information Retrieval (PAIR). Information regarding the status of an application can be obtained from the (PAIR) system. Status information for published applications may be obtained from either Private PAIR or Public PAX. Status information for unpublished applications is available through Private PAIR only. For more information about the PAIR system, see http://pair-direct.uspto.gov. Should you have questions on access to the Private PAIR system, please feel free to contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). Applicants are invited to contact the Office to schedule an in-person interview to discuss and resolve the issues set forth in this Office Action. Although an interview is not required, the Office believes that an interview can be of use to resolve any issues related to a patent application in an efficient and prompt manner.
/MICHAEL L DIGNAN/Examiner, Art Unit 1723
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