DETAILED ACTION
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 4/14/26 has been entered.
Response to Amendment
Claims 1-20 and 22 are currently pending. Claims 1-13, 17, and 18 are withdrawn from further consideration as being drawn to a non-elected invention. Claim 21 is cancelled. The previously stated 112, 2nd paragraph rejection of claims 14-20 and 22 is withdrawn. The amended claim 14 does not overcome the previously stated 103 rejections. Therefore, upon further consideration, claims 14-16, 19, 20, and 22 are rejected under the following 103 rejections.
Claim Objections
Claim 14 is objected to because of the following informalities: there is an extra “is” in line 12. Appropriate correction is required.
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 14, 15, 19, 20, and 22 are rejected under 35 U.S.C. 103 as being unpatentable over Li et al (CN 104103791 A, machine translation) in view of He et al (US 2019/0379045).
Regarding claims 14, 15, 19, and 20, Li et al discloses a method of preparing a composite diaphragm (composite membrane) for a lithium-sulfur battery, the method comprising:
providing a polymer film/polymer layer “2” (polymeric separator membrane) comprising a thickness (membrane thickness) of 1 to 30 um;
forming (synthesizing) a graphene (GO) dispersion; and
printing the graphene dispersion on the polymer layer to form a multilayer composite structure of a first conductive layer/polymer layer/second conductive layer on both sides of the polymer layer, the second conductive layer “1” is separated from the first conductive layer “1” by the polymer layer thickness; and
drying the composite structure after printing the first conductive layer and after printing the second conductive layer;
positioning a metal lithium sheet (lithium foil) as a counter electrode of the lithium-sulfur battery;
wherein the graphene dispersion comprises graphene synthesized by ultrasonication;
wherein the printing process is compatible with existing printing technology;
wherein the graphene dispersion is composed of graphene and ethanol (organic solvents) ([0039]-[0043],[0064],[0088]). Examiner’s note: the Office takes the position that existing printing technology includes using a commercial printer and a commercial ink cartridge containing the graphene dispersion.
However, Li et al does not expressly teach a graphene oxide dispersion; wherein the GO coating defines a plurality of nanopores, wherein each of the plurality of nanopores is configured to inhibit passage of polysulfides across the composite membrane while allowing lithium ions to freely pass through the composite membrane (claim 14).
He et al discloses a lithium ion reservoir (GO coating) comprising lithium ion-conducting porous framework structure having pores with a pore size from 1 nm to 500 um, wherein the porous framework structure contains a conducting foam comprising pores having a pore size from 2 nm to 50 nm; and a graphene dispersion having a graphene material that is selected from graphene, graphene oxide, … ([0021],[0036], [0091]).
Therefore, it would have been obvious to one of ordinary skill in the art at the time the invention was made to modify the Li method of preparing a composite diaphragm to include graphene coating that defines a plurality of nanopores, wherein each of the plurality of nanopores is 2 nm to 50 nm in order to help stabilize the lithium metal-electrolyte interface zone and prevent dendrite formation, leading to much longer cycle-life for safe rechargeable lithium metal battery ([0155]). In addition, the invention as a whole would have been obvious to one of ordinary skill in the art at the time the invention was made because the disclosure of He et al indicates that graphene oxide is a suitable material for use as graphene dispersion. The selection of a known material based on its suitability for its intended use has generally been held to be prima facie obvious (MPEP §2144.07). As such, it would be obvious to use graphene oxide.
Examiner’s note: the Office takes the position that the limitation “is configured to inhibit passage of polysulfide across the composite membrane while allowing lithium ions to freely pass through the composite membrane” is an inherent characteristic of the Li/He composite diaphragm based upon a pore size of the graphene oxide coating of 2 nm. According to para.[0041] of the specification of the present application, “The GO coating defines a plurality of nanopores … the composite membrane has a pore size, e.g. nanopore has a diameter, Dp, that is less than about 10 nm … Such nanopore is configured to block the primary contributors to the shuttling currents, i.e. lithium polysulfide”. Therefore, there is no evidence of criticality of the claimed size of the nanopores.
Regarding claim 22, Li et al as modified by He et al does not expressly teach each of the plurality of nanopores that is less than 1 nm.
However, it would have been obvious to one of ordinary skill in the art at the time the invention was made to modify the Li/He method of preparing a composite diaphragm to include each of the plurality of nanopores that is less than about 1 nm because even if the range of prior art and the claimed range do not overlap, obviousness may still exist if the ranges are close enough that one of ordinary skill in the art would not expect a difference in properties (In re Woodruff 16 USPQ 2d 1934 (Fed. Cir. 1990)). There is no evidence of criticality of the claimed pore size of the GO coating.
Claim 16 is rejected under 35 U.S.C. 103 as being unpatentable over Li et al in view of He et al as applied to claim 15 above, and further in view of Cho et al (US 2018/0076404) and Ikenuma et al (US 2015/0166348).
However, Li et al as modified by He et al does not expressly teach a type of GO that is Type I GO functionalized with a carboxyl group (COOH) and synthesizing the GO dispersion comprises mixing a 25 mL (milliliters) dispersion of original GO at a concentration of 2 mg/g (milligrams per gram) of deionized water with 5 mL of hydrogen bromide (HBr) at room temperature under vigorous stirring for 12 hours, adding 1 g of oxalic acid and stirring for 4 hours and washing with deionized water to remove the acid using centrifugation at 10,000 revolutions per minute (claim 16).
Cho et al discloses a method of preparing a graphene oxide modified (functionalized) with carboxyl group by dispersing graphene oxide powder at a concentration of 2.5 g/L (mg/g) in water, 30 ml of which was added with 5 ml of HBr (hydrogen bromide), vigorously stirring at room temperature for 12 hrs, adding with oxalic acid, and stirring for 4 hours, thus preparing carboxyl group modified graphene oxide, which was then filtered (washed) ([0112]).
Therefore, it would have been obvious to one of ordinary skill in the art at the time the invention was made to modify the Li/He method of preparing a composite diaphragm to include Type I GO functionalized with a carboxyl group (COOH) and synthesizing the GO dispersion comprises mixing a 25 mL (milliliters) dispersion of original GO at a concentration of 2 mg/g (milligrams per gram) of deionized water with 5 mL of hydrogen bromide (HBr) at room temperature under vigorous stirring for 12 hours, adding 1 g of oxalic acid and stirring for 4 hours in order to utilize a graphene having a functional group that is stable and controllable during low temperature processing, thereby improving electrical properties such as the work function of graphene ([0005],[0006]).
However, Li et al as modified by He et al and Cho et al does not expressly teach washing with deionized water to remove the acid using centrifugation at 10,000 revolutions per minute (claim 16).
Ikenuma et al discloses washing graphene oxide by centrifugation of a mixed solution formed by adding water to graphene oxide ([0253]). Examiner’s note: although Ikenuma et al does not expressly teach centrifugation at 10,000 revolutions per minute, the Office takes the position that it is within the level of skill of one of ordinary skill in the art to wash the graphene oxide at 10,000 revolutions per minute by routine experimentation.
Therefore, it would have been obvious to one of ordinary skill in the art at the time the invention was made to modify the Li/He/Cho method of preparing a composite diaphragm to include washing with deionized water to remove the acid using centrifugation at 10,000 revolutions per minute because the substitution of one known method of washing for another would have yielded predictable results to one of ordinary skill in the art at the time of the invention.
Claim 22 is rejected under 35 U.S.C. 103 as being unpatentable over Li et al in view of He et al as applied to claim 14 above, and further in view of Yu et al (WO 2018/140423 A1).
However, Li et al as modified by He et al does not expressly teach the drying comprising about 4 hours of drying at room temperature followed by 2 hours of drying at 60°C (claim 22).
Yu et al discloses printing GO coating on the surface of a support comprising 4 hours of drying at room temperature followed by 2 hours at 80°C (pg. 9, lines 20-24).
Therefore, it would have been obvious to one of ordinary skill in the art at the time the invention was made to modify the Li/He method of preparing a composite diaphragm to include about 4 hours of drying at room temperature followed by 2 hours of drying at 80°C in order to produce a high quality layer of graphene oxide on the substrate and to precisely control the thickness of the graphene oxide layer and its two dimensional distribution on the substrate (pg. 4, lines 1-4). In addition, it would have been obvious to one of ordinary skill in the art at the time the invention was made to modify the Li/He/Yu method of preparing a composite diaphragm to include drying at 60°C because it has been held that the discovery of an optimum value of a result effective variable in a known process is ordinarily within the skill of the art. In re Boesch, 205 USPQ 215 (CCPA 1980). Where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation. In re Aller, 220 F.2d 454. 456, 105 USPQ 233, 235 (CCPA 1955)). There is no evidence of criticality of the claimed drying temperature.
Claims 14, 15, 19, 20, and 22 are rejected under 35 U.S.C. 103 as being unpatentable over Li et al (CN 104103791 A, machine translation) in view of He et al (US 2019/0379045), and further in view of Guo et al (CN 103490027 A, machine translation).
Regarding claims 14, 15, 19, 20, and 22, Li et al discloses a method of preparing a composite diaphragm (composite membrane) for a lithium-sulfur battery, the method comprising:
providing a polymer film “2” (polymeric separator membrane) comprising a thickness (membrane thickness) of 1 to 30 um;
forming (synthesizing) a graphene (GO) dispersion; and
printing the graphene dispersion on the polymer layer to form a multilayer composite structure of a first conductive layer/polymer layer/second conductive layer on both sides of the polymer layer, the second conductive layer “1” is separated from the first conductive layer “1” by the polymer layer thickness; and
drying the composite structure after printing the first conductive layer and after printing the second conductive layer;
positioning a metal lithium sheet (lithium foil) as a counter electrode of the lithium-sulfur battery;
wherein the graphene dispersion comprises graphene synthesized by ultrasonication;
wherein the printing process is compatible with existing printing technology;
wherein the graphene dispersion is composed of graphene and ethanol (organic solvent) ([0039]-[0043],[0064],[0088]). Examiner’s note: the Office takes the position that existing printing technology includes using a commercial printer and a commercial ink cartridge containing the graphene dispersion.
However, Li et al does not expressly teach a graphene oxide dispersion (claim 14).
He et al discloses a graphene dispersion having a graphene material that is selected from graphene, graphene oxide, … ([0021],[0036],[0091]).
Therefore, the invention as a whole would have been obvious to one of ordinary skill in the art at the time the invention was made because the disclosure of He et al indicates that graphene oxide is a suitable material for use as a graphene dispersion. The selection of a known material based on its suitability for its intended use has generally been held to be prima facie obvious (MPEP §2144.07). As such, it would be obvious to use graphene oxide.
However, Li et al as modified by He et al does not expressly teach a GO coating that defines a plurality of nanopores, wherein each of the plurality of nanopores is configured to inhibit passage of polysulfides across the composite membrane while allowing lithium ions to freely pass through the composite membrane (claim 14); wherein each of the plurality of nanopores is less than 1 nm (nanometer) (claim 22).
Guo et al discloses a porous barrier layer (GO coating) comprising micropores having a micropore diameter of 0.6-2 nm with an example of 0.6 nm, wherein the porous barrier layer has good selective permeability, which can allow lithium ions to pass through, and at the same time has a blocking effect on lithium polysulfide ([0009],[0012],[0096]).
Therefore, it would have been obvious to one of ordinary skill in the art at the time the invention was made to modify the Li/He method of preparing a composite diaphragm to include GO coating defining a plurality of nanopores, wherein each of the plurality of nanopores is 0.6 nm in order to provide a lithium-sulfur battery that exhibits better cycle capacity and cycle stability ([0012]).
Claim 16 is rejected under 35 U.S.C. 103 as being unpatentable over Li et al in view of He et al and Guo et al as applied to claim 15 above, and further in view of Cho et al (US 2018/0076404) and Ikenuma et al (US 2015/0166348).
However, Li et al as modified by He et al and Guo et al does not expressly teach a type of GO that is Type I GO functionalized with a carboxyl group (COOH) and synthesizing the GO dispersion comprises mixing a 25 mL (milliliters) dispersion of original GO at a concentration of 2 mg/g (milligrams per gram) of deionized water with 5 mL of hydrogen bromide (HBr) at room temperature under vigorous stirring for 12 hours, adding 1 g of oxalic acid and stirring for 4 hours and washing with deionized water to remove the acid using centrifugation at 10,000 revolutions per minute (claim 16).
Cho et al discloses a method of preparing a graphene oxide modified (functionalized) with carboxyl group by dispersing graphene oxide powder at a concentration of 2.5 g/L (mg/g) in water, 30 ml of which was added with 5 ml of HBr (hydrogen bromide), vigorously stirring at room temperature for 12 hrs, adding with oxalic acid, and stirring for 4 hours, thus preparing carboxyl group modified graphene oxide, which was then filtered (washed) ([0112]).
Therefore, it would have been obvious to one of ordinary skill in the art at the time the invention was made to modify the Li/He/Guo method of preparing a composite diaphragm to include Type I GO functionalized with a carboxyl group (COOH) and synthesizing the GO dispersion comprises mixing a 25 mL (milliliters) dispersion of original GO at a concentration of 2 mg/g (milligrams per gram) of deionized water with 5 mL of hydrogen bromide (HBr) at room temperature under vigorous stirring for 12 hours, adding 1 g of oxalic acid and stirring for 4 hours in order to utilize a graphene having a functional group that is stable and controllable during low temperature processing, thereby improving electrical properties such as the work function of graphene ([0005],[0006]).
However, Li et al as modified by He et al, Guo et al, and Cho et al does not expressly teach washing with deionized water to remove the acid using centrifugation at 10,000 revolutions per minute (claim 16).
Ikenuma et al discloses washing graphene oxide by centrifugation of a mixed solution formed by adding water to graphene oxide ([0253]). Examiner’s note: although Ikenuma et al does not expressly teach centrifugation at 10,000 revolutions per minute, the Office takes the position that it is within the level of skill of one of ordinary skill in the art to wash the graphene oxide at 10,000 revolutions per minute by routine experimentation.
Therefore, it would have been obvious to one of ordinary skill in the art at the time the invention was made to modify the Li/He/Guo/Cho method of preparing a composite diaphragm to include washing with deionized water to remove the acid using centrifugation at 10,000 revolutions per minute because the substitution of one known method of washing for another would have yielded predictable results to one of ordinary skill in the art at the time of the invention.
Claim 22 is rejected under 35 U.S.C. 103 as being unpatentable over Li et al in view of He et al and Guo et al as applied to claim 14 above, and further in view of Yu et al (WO 2018/140423 A1).
However, Li et al as modified by He et al and Guo et al does not expressly teach the drying comprising about 4 hours of drying at room temperature followed by 2 hours of drying at 60°C (claim 22).
Yu et al discloses printing GO coating on the surface of a support comprising 4 hours of drying at room temperature followed by 2 hours at 80°C (pg. 9, lines 20-24).
Therefore, it would have been obvious to one of ordinary skill in the art at the time the invention was made to modify the Li/He/Guo method of preparing a composite diaphragm to include about 4 hours of drying at room temperature followed by 2 hours of drying at 80°C in order to produce a high quality layer of graphene oxide on the substrate and to precisely control the thickness of the graphene oxide layer and its two dimensional distribution on the substrate (pg. 4, lines 1-4). In addition, it would have been obvious to one of ordinary skill in the art at the time the invention was made to modify the Li/He/Guo/Yu method of preparing a composite diaphragm to include drying at 60°C because it has been held that the discovery of an optimum value of a result effective variable in a known process is ordinarily within the skill of the art. In re Boesch, 205 USPQ 215 (CCPA 1980). Where the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation. In re Aller, 220 F.2d 454. 456, 105 USPQ 233, 235 (CCPA 1955)). There is no evidence of criticality of the claimed drying temperature.
Response to Arguments
Applicant's arguments filed 4/14/26 have been fully considered but they are not persuasive.
The Applicant argues that “Applicant has amended independent claim 14 to recite, among other elements, "positioning a piece of lithium foil on the composite membrane”. The prior art, taken alone or in combination, is silent with regard to this element.”.
In response, the Office first points out that Li et al discloses “All electrode sheets were assembled into 2025 type button cells … with the metal lithium sheet (lithium foil) as the counter electrode” (see para. [0088]). Since the Li lithium-sulfur battery is formed by a positive electrode, composite film, and a counter electrode as disclosed in para. [0064],[0088], Li et al necessarily teaches a metal lithium sheet (lithium foil) that is positioned on the composite film (composite membrane).
Conclusion
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/T.S.C/Examiner, Art Unit 1751
/Haroon S. Sheikh/Primary Examiner, Art Unit 1751
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