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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 10 June 2026 has been entered.
Status of Claims
Claims 1, 4, 6-11, 13-14, 16-18, 20-21, 23, 27, and 38-39 are currently pending
Claims 1 and 39 are amended
Claims 2-3 have been cancelled
Claims 23, 27, and 38 have been previously withdrawn
Status of Amendments
The amendment filed 10 June 2026 has been fully considered, but does not place the application in condition for allowance.
Status of Objections and Rejections of the Office Action from 10 February 2026
The 103 rejections over Yao in view of Jiang and further in view of Wu have been withdrawn. However, new grounds of rejection over Yao in view of Wu has been set forth.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1, 4, 6-11, 13, 14, 16-18, 20,21, and 39 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being incomplete for omitting essential steps, such omission amounting to a gap between the steps. See MPEP § 2172.01. The omitted step is: Discretely distributing ethyl cellulose binder between sulfide solid electrolytes using point gluing.
Claim 1 recites the limitation that “the solid-state electrolyte enables continuous ion conduction across the membrane.” According to paragraph [0080] of the instant specification, the continuous ion conduction attribute is connected to multiple properties of an SE membrane, such as a high volume fraction of Li6PS5Cl, a high ionic conductivity, a low porosity, and a high density. One of ordinary skill in the art would expect that performing the claimed method would yield all of these properties, including the continuous ion conduction. However, in Applicant’s Arguments/Remarks Made in an Amendment dated 10 June 2026, Applicant states that “the ion conduction pathway is determined by the distributions of Li6PS5Cl, ethyl cellulose, and pores of the membrane, in which the ethyl cellulose is distributed throughout the membrane, but does not form a continuous wrapping with the Li6PS5Cl (para [0080]). This enables the continuous ion conduction across the membrane.” Examiner agrees that this is also disclosed in paragraph [0080] of the instant specification. However, this particular property, regarding the ethyl cellulose forming point contact with the Li6PS5Cl, instead of areal wrapping, is directed to a method of point-to-point gluing [0058] which discretely distributes an ethyl cellulose binder between sulfide SEs [0066] and is not part of the presently claimed method. Applicant’s remarks indicate that the ethyl cellulose binder point gluing is essential in providing the claimed continuous ion conduction across the membrane, but is not reflected in the presently rejected claims. For the purposes of this office action, a source that teaches the claimed method will also be considered to teach the newly claimed continuous ion conduction limitation.
Claims 4, 6-11, 13-14, 16-18, 20-21, and 39 are rejected for being dependent from a rejected base claim.
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, 4, 6-11, 13-14, 16-18, 20-21, and 39 are rejected under 35 U.S.C. 103 as being unpatentable over Yao et al. (CN 112909329 A), hereinafter Yao, in view of Wu et al. (CN 109524599 A), hereinafter Wu.
Regarding claim 1, Yao teaches a method of making a solid-state electrolyte, the method comprising:
dissolving ethyl cellulose, in this case the binder (pg. 3, ¶ 5), in toluene (pg. 3 ¶ 4);
dispersing a sulfide solid electrolyte in the nonpolar solvent, in this case the sulfide electrolyte is mixed in with the solvent, binder, and a dispersant (pg. 2, ¶ 6), wherein the sulfide solid electrolyte is Li6PS5Cl, in this case Li6PS5X where X is Cl, Br, or I (pg. 4, ¶ 13);
casting the dispersion of the sulfide solid electrolyte in the toluene to form a thin membrane, in this case uniformly dispersing the slurry on the surface of the electrode material (pg. 2, ¶ 7);
applying pressure to the membrane to form a thinner membrane, in this case forming to obtain the ultra-thin sulfide electrolyte layer, preferably comprising one or more of flat static pressure, isostatic pressing, rolling and punching (pg. 6, ¶ 4), which one of ordinary skill in the art would expect to form a thinner membrane than the initial dispersed slurry; and
heating the thin membrane to remove the toluene, in this case orderly drying, thereby forming a solid-state electrolyte (pg. 2, ¶ 7).
Yao is silent as to the ethyl cellulose being a dispersant. However, "products of identical chemical composition cannot have mutually exclusive properties." In re Spada, 911 F.2d 705, 709, 15 USPQ2d 1655, 1658 (Fed. Cir. 1990). Therefore, one of ordinary skill in the art would expect the ethyl cellulose to also behave like a dispersant, in addition to being a binder, as taught by the instant application.
Yao is silent as to casting the dispersion of the sulfide solid electrolyte in the toluene under vacuum filtration. However, Wu teaches a sulfide solid electrolyte preparation method comprising dispersing the slurry into a vacuum filtration device for vacuum filtration (pg. 3, ¶ 7). Wu further teaches drying and rolling the solid electrolyte diaphragm after vacuum filtration (pg. 3, ¶ 8) to bring the thickness of the diaphragm in embodiment A from 100 μm to 60 μm (pg. 3, ¶ 14-pg. 4, ¶ 1).
Yao and Wu are both considered to be analogous to the claimed invention because they are in the same field of sulfide solid electrolyte preparation methods. Therefore, it would have been obvious to someone of ordinary skill in the art before the effective filing date of the claimed invention to modify the dispersion technique of Yao with the vacuum filtration dispersion technique of Wu. Simple substitution of one known method for another to obtain predictable results, in this case using vacuum filtration to form a thin sulfide solid electrolyte diaphragm, has been held to support a conclusion of obviousness. See MPEP 2143.I.B. Further, it would have been obvious to someone of ordinary skill in the art before the effective filing date of the claimed invention to modify the forming method of Yao to specifically form a thinner membrane, as taught by Wu. Doing so would have produced a flexible diaphragm sulfide solid electrolyte with high ionic conductivity (pg. 4, ¶ 1) as well as large mechanical strength and uniform thickness (abstract).
Yao is further silent as to the solid-state electrolyte enabling continuous ion conduction across the membrane. However, modified Yao teaches a substantially identical process to the claimed invention. Modified Yao teaches the method of claim 1 with Yao further teaching the identical materials (pg. 3, ¶ 4 and pg. 4, ¶ 13), thickness (pg. 6, ¶ 7 and pg. 7, ¶ 5), and weight percent of specific materials (pg. 5, ¶ 9 and pg. 9, ¶ 6). Therefore, one of ordinary skill in the art would expect the solid-state electrolyte produced by the taught method to inherently enable continuous ion conduction across the membrane. Where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established. In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977). Further, "Products of identical chemical composition cannot have mutually exclusive properties." In re Spada, 911 F.2d 705, 709, 15 USPQ2d 1655, 1658 (Fed. Cir. 1990).
Regarding claims 4 and 6, modified Yao teaches the method of claim 1. Yao further teaches the solid-state electrolyte having a thickness of 1-50 µm (pg. 6, ¶ 7), which overlaps with the claimed 20-50 µm, and Embodiment 1 of Yao further teaches an ultra-thin sulfide electrolyte layer with a thickness of 20 µm (pg. 7, ¶ 5). If the prior art discloses a point within the claimed range, the prior art anticipates the claim. UCB, Inc. v. Actavis Labs. UT, Inc., 65 F.4th 679, 687, 2023 USPQ2d 448 (Fed. Cir. 2023).
Regarding claims 7-11, 13-14, 17-18, and 20-21, modified Yao teaches the method of claim 1. Yao further teaches the solid-state electrolyte having a conductivity of 10-5 to 5*10-2 S/cm, or 0.01 to 50 mS/cm (pg. 6, ¶ 7), which overlaps with the claimed range of 0.75 to 5 mS/cm, as required by claims 10 and 11, and Embodiment 1 of Yao further teaches an ultra-thin sulfide electrolyte layer having a conductivity of 4.4*10-3 S/cm, or 4.4 mS/cm (pg. 7, ¶ 5). However, Yao is silent as to the temperature at which the conductivity was measured. Yao is further silent as to the resistance of the solid-state electrolyte, as required by claims 7-9, the ion conductivity of the solid-state electrolyte, as required by claims 13-14, the porosity of the solid-state electrolyte, as required by claims 17-18, the homogeneous distribution of chlorine, sulfur, and phosphorus throughout the solid-state electrolyte, as required by claim 20, and the continued ion conductance of the solid-state electrolyte allowed by the ethyl cellulose, as required by claim 21.
However, modified Yao teaches a substantially identical process to the claimed invention. Modified Yao teaches the method of claim 1 with Yao further teaching the identical materials (pg. 3, ¶ 4 and pg. 4, ¶ 13), thickness (pg. 6, ¶ 7 and pg. 7, ¶ 5), and weight percent of specific materials (pg. 5, ¶ 9 and pg. 9, ¶ 6). Therefore, one of ordinary skill in the art would expect the product produced by the taught method to have the inherent values claimed in claims 7-11, 13-14, 17-19, and 20-21. Where the claimed and prior art products are identical or substantially identical in structure or composition, or are produced by identical or substantially identical processes, a prima facie case of either anticipation or obviousness has been established. In re Best, 562 F.2d 1252, 1255, 195 USPQ 430, 433 (CCPA 1977). Further, "Products of identical chemical composition cannot have mutually exclusive properties." In re Spada, 911 F.2d 705, 709, 15 USPQ2d 1655, 1658 (Fed. Cir. 1990).
Regarding claim 16, modified Yao teaches the method of claim 1. Yao further teaches the bonding agent being from about 0.5% to 30% of the total mass of the mixture (pg. 5, ¶ 9), which overlaps with the claimed range of 1 to 5 wt%, and Embodiment 6 further teaches 5% of the total mass of the mixture being ethyl cellulose (pg. 9, ¶ 6). If the prior art discloses a point within the claimed range, the prior art anticipates the claim. UCB, Inc. v. Actavis Labs. UT, Inc., 65 F.4th 679, 687, 2023 USPQ2d 448 (Fed. Cir. 2023).
Regarding claim 39, modified Yao teaches the method of claim 1. Yao further teaches the elements of the sulfide solid electrolyte being homogenously distributed from the dispersing of the sulfide solid electrolyte in the toluene. In this case, the slurry components, including the sulfide solid electrolyte, are taught to be mixed uniformly to obtain the electrolyte slurry (pg. 3, ¶ 8).
Response to Arguments
Applicant's arguments filed 10 June 2026 have been fully considered but they are not persuasive.
Applicant argues that Wu actively teaches a fiber-reinforced composite and does not teach a non-fibrous solid-state electrolyte. Examiner respectfully points out that Wu teaches a method of preparing a sulfide solid state electrolyte, which is considered to be analogous to the claimed invention. Therefore, it would have been obvious to modify the sulfide solid-state electrolyte preparation method of Yao with teachings from the sulfide solid-state electrolyte preparation method of Wu. Examiner further notes that the presently claimed invention does not require a strictly non-fibrous electrolyte.
Applicant further outlines the deficiencies of using cellulose in place of ethyl cellulose. However, the present rejection does not suggest replacing the ethyl cellulose with regular cellulose, as only the method of Wu is being used to modify Yao, not the materials. Therefore, the point is moot.
Applicant’s arguments with respect to the use of ethyl cellulose as a dispersant in claim 1 have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to DUSTIN KENWOOD VAN KIRK whose telephone number is (703)756-4717. The examiner can normally be reached Monday-Friday 9am-5pm EST.
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/DUSTIN VAN KIRK/Examiner, Art Unit 1722
/ANCA EOFF/Primary Examiner, Art Unit 1722
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