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 .
Response to Amendment, Claim Status, and Other Notes
The amendment filed 19 December 2025 has been entered. Applicant’s amendments to the claims and specification have overcome each and every objection set forth in the Office Action mailed 1 October 2025. Claims 3 and 6 have been canceled. Claims 10–14 have been added. Claims 1, 2, 4, 5, and 7–14 are pending in the application.
Note that paragraph numbers cited in this Office Action in reference to the instant application are referring to the paragraph numbering of the PGPub of the instant application. See US 2023/0187692 A1.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 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 considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. 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.
Claims 1, 2, 4, 7–11, 13, and 14 are rejected under 35 U.S.C. 103 as being unpatentable over Kim et al. (US 2023/0327186 A1) in view of Zhang et al. (All-in-one improvement toward Li6PS5Br-based solid electrolytes triggered by compositional tune) and further in view of Minafra et al. (Effect of Si substitution on the structural and transport properties of superionic Li-argyrodites).
Regarding Claims 1, 7, 9, and 13, Kim discloses a solid electrolyte (see sulfide solid electrolyte, [0024]) for a solid-state battery (see all-solid secondary battery, [0059]) (Claim 1), or alternatively, Kim discloses a solid-state battery (see all-solid secondary battery, [0059]) (Claim 9). Kim does not disclose the solid electrolyte/solid-state battery comprising an oxysulfide-based compound represented by the following chemical formula:
[Chemical Formula]
LiaMbPcSdOeXf,
wherein: 5 ≤ a ≤ 7, 0 < b ≤ 1, 0 ≤ c < 1, 2.5 ≤ d ≤ 5, 0 < e ≤ 2 and 1 < f ≤ 1.5,
M is one selected from the group consisting of Si, Ti, Ta, Nb, As, Sb, Sn and Al, and
X includes Cl and Br (Claims 1 and 9),
or more narrowly wherein a, b, c, d, e, and f are 5.6 ≤ a ≤ 6, 0.1 ≤ b ≤ 0.3, 0.7 ≤ c < 1, 4 ≤ d ≤ 5, 0 ≤ e ≤ 0.6, and 1 < f ≤ 1.5, respectively (Claims 7 and 13).
Instead, Kim discloses the solid electrolyte comprising a sulfide-based compound represented by the chemical formula: Li5.8PS4.8ClBr0.2 ([0076]), which can be understood as a variant of the known Li6PS5X lithium argyrodite family of solid electrolytes ([0060], [0076]).
Zhang teaches a solid electrolyte for a solid-state battery (p. 162 ¶ “All-solid-state lithium-ion…”) comprising an oxysulfide-based compound represented by the chemical formula: Li6PS5-xOxBr (p. 164 ¶ “Fig. 1a shows…”), also a variant of the Li6PS5X lithium argyrodite family (p. 163 ¶ “Among all promising…” and p. 163 ¶ “Apart from the…”), wherein S2− is partially substituted with O2− to improve properties such as air stability (p. 164 ¶ “As partial substitution…”), chemical/electrochemical stability towards Li metal (p. 164–165 ¶ “Understanding the DC…”), dendrite suppression (p. 164–165 ¶ “Understanding the DC…”), and compatibility with oxide-based cathodes (p. 164–165 ¶ “Cell performance is…”). Zhang teaches that a balance of high ionic conductivity, good air stability, and dendrite suppression capability were found to be achieved for Li6PS5-xOxBr when the extent of substitution is x = 0.3.
Kim and Zhang are analogous to the claimed invention as they are in the same field of solid electrolytes based on the Li6PS5X lithium argyrodite family. Furthermore, KSR Rationale C states that it is obvious to use a “known technique to improve similar devices (methods, or products) in the same way” (MPEP § 2143.01.I). In the instant case, Kim and Zhang disclose similar solid electrolytes which belong to the same family of Li6PS5X lithium argyrodites, and thus it would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the claimed invention to modify the solid electrolyte of Kim with the technique of Zhang, i.e. to partially substitute S2− with O2− to the same extent as taught by Zhang, in order to achieve improved air stability, improved chemical/electrochemical stability towards Li metal, suppressed dendrite formation, and better compatibility with oxide-based cathodes.
Furthermore, Minafra teaches a solid electrolyte for a solid-state battery (p. 645 ¶ “Solid ion conductors…”) comprising a sulfide-based compound represented by the chemical formula Li6+xP1−xSixS5Br (p. 647 ¶ “The Li+ superionic…”), also a variant of the Li6PS5X lithium argyrodite family (p. 645 ¶ “Fig. 1 shows…”), wherein P5+ is partially substituted with Si4+ (note that an equivalent amount of Li+ is added to balance charge) to improve ionic conductivity by increasing lithium concentration and occupancy of Li+ on the transition state for hopping (p. 645–646 “While many Cu+…”). Minafra teaches that Li6+xP1−xSixS5Br can be synthesized for values of 0 < x ≤ 0.3 without reaching a solubility limit (p. 647 ¶ “Fig. 3 shows…”).
Minafra is analogous to the claimed invention as it is in the same field of solid electrolytes based on the Li6PS5X lithium argyrodite family. Furthermore, KSR Rationale C states that it is obvious to use a “known technique to improve similar devices (methods, or products) in the same way” (MPEP § 2143.01.I). In the instant case, Kim and Minafra disclose similar solid electrolytes which belong to the same family of Li6PS5X lithium argyrodites, and thus it would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the claimed invention to modify the solid electrolyte of Kim with the technique of Minafra, i.e. to partially substitute P5+ with Si4+ to the same extent as taught by Minafra, in order to achieve improved ionic conductivity by increasing lithium concentration and Li+ occupancy on the transition state.
One of ordinary skill in the art will understand that, starting from the sulfide-based compound represented by the chemical formula: Li5.8PS4.8ClBr0.2 of Kim, modification as set forth above via (1) substitution of 0.3 mol S2− with O2− as taught by Zhang and (2) substitution of less than or equal to 0.3 mol of P5+ with Si4+, denoted herein as “z” mol wherein 0 < z ≤ 0.3 (note that an equivalent mol Li+ is also added to balance charge), as taught by Minafra, will result in an oxysulfide-based compound of modified Kim represented by the chemical formula: Li5.8+zP1.0−zSi0.0+zS4.8−0.3O0.0+0.3ClBr0.2, i.e. Li5.8+zP1.0−zSizS4.5O0.3ClBr0.2 where 0 < z ≤ 0.3, which lies within the claimed ranges of Claims 1 and 9 and overlaps with the claimed ranges of Claims 7 and 13. Note that when the claimed ranges overlap or lie inside ranges disclosed by the prior art, a prima facie case of obviousness exists (MPEP § 2144.05.I).
Regarding Claims 2 and 10, modified Kim discloses the solid electrolyte and solid-state battery of Claims 1 and 9, respectively. As set forth in the rejection of Claims 1 and 9 above, modified Kim discloses (Kim [0060]; Zhang p. 163 ¶ “Among all promising…” and p. 163 ¶ “Apart from the…”; Minafra p. 645 ¶ “Fig. 1 shows…”) wherein the oxysulfide-based compound includes an argyrodite crystal structure.
Regarding Claims 4 and 11, modified Kim discloses the solid electrolyte and solid-state battery of Claims 1 and 9 respectively. As set forth in the rejection of Claims 1 and 9 above, modified Kim discloses an oxysulfide-based compound represented by the chemical formula: Li5.8+zP1.0−zSizS4.5O0.3ClBr0.2 where 0 < z ≤ 0.3, which satisfies the limitation wherein a content of Cl is higher than a content of Br.
Regarding Claims 8 and 14, modified Kim discloses the solid electrolyte and solid-state battery of Claims 1 and 9, respectively. Modified Kim does not explicitly disclose wherein compared to a solid electrolyte of Li2MbPc1SdOeX (0 ≤ c1 ≤ 1), the oxysulfide-based compound has a higher ionic conductivity after exposure to atmosphere. However, it is submitted that such limitations are simply measurements of, and thus descriptions of, inherent properties of the instant oxysulfide-based compound.
Applicant does not explicitly state which specific features of the oxysulfide-based compound result in it having a higher ionic conductivity than the solid electrolyte Li2MbPc1SdOeX (0 ≤ c1 ≤ 1) after exposure to the atmosphere. However, Applicant appears to disclose ([0054]) that oxysulfide-based compounds of Applicant’s present disclosure, i.e. oxysulfide-based compounds represented by the claimed Chemical Formula and e.g. Embodiments 1–9, would possess this property.
In comparison, modified Kim discloses the oxysulfide-based compound Li5.8+zP1.0−zSizS4.5O0.3ClBr0.2 where 0 < z ≤ 0.3, which satisfies the Chemical Formula of Claims 1 and 9 and is very similar to Embodiments 1–5 of the instant application, which Applicant discloses ([0074]–[0080], TABLE 1) to be oxysulfide-based compounds represented by the chemical formulas Li6Si0.1P0.9S4.7O0.2ClBr0.1, Li5.9Si0.1P0.9S4.6O0.2ClBr0.2, Li5.8Si0.1P0.9S4.5O0.2ClBr0.3, Li5.7Si0.1P0.9S4.4O0.2ClBr0.4, and Li5.6Si0.1P0.9S4.3O0.2ClBr0.5, respectively.
MPEP § 2112.01.I states that 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 ether anticipation or obviousness has been established.
It is submitted that the oxysulfide-based compound of modified Kim is substantially identical to the oxysulfide-based compound of e.g. Embodiments 1–5 of the instant application, as set forth above, such that it would inherently possess the same properties, exhibit the same results, and thus anticipate the claimed limitation, i.e. wherein compared to a solid electrolyte of Li2MbPc1SdOeX (0 ≤ c1 ≤ 1), the oxysulfide-based compound has a higher ionic conductivity after exposure to atmosphere.
Assuming, arguendo, that the property recited in the claimed limitation is not anticipated, as there is no evidence on the record that any differences between the instantly claimed oxysulfide-based compound and that of modified Kim are critical, and as the conditions of the prior art significantly overlap the relevant conditions disclosed in the instant specification, it is submitted that prior to the effective filing date, one having ordinary skill in the art would have found the oxysulfide-based compound of modified Kim and that of the instant application to be obvious variants of one another.
Claims 5 and 12 are rejected under 35 U.S.C. 103 as being unpatentable over Kim et al. (US 2023/0327186 A1) in view of Zhang et al. (All-in-one improvement toward Li6PS5Br-based solid electrolytes triggered by compositional tune) and further in view of Minafra et al. (Effect of Si substitution on the structural and transport properties of superionic Li-argyrodites) as applied to Claims 4 and 11 above, as evidenced by Wang et al. (Fast Ion Conduction and Its Origin in Li6−xPS5−xBr1+x).
Regarding Claims 5 and 12, modified Kim discloses the solid electrolyte and solid-state battery of Claims 4 and 11, respectively. Modified Kim does not explicitly disclose wherein within the content of the X, a lattice constant of the oxysulfide-based compound increases as the content of Cl is constant and the content of Br increases. However, it is submitted that such limitations are simply measurements of, and thus descriptions of, inherent properties of the instant oxysulfide-based compound.
Applicant discloses ([0049]) that the lattice constant of the oxysulfide-based compound increases as the content of Cl is constant and the content of Br increases because Br, which has a larger ionic radius than S, is employed inside the structure of the oxysulfide-based compound.
Applicant further discloses ([0074]–[0080], TABLE 1) Embodiments 1–5, which are oxysulfide-based compounds represented by the chemical formulas Li6Si0.1P0.9S4.7O0.2ClBr0.1, Li5.9Si0.1P0.9S4.6O0.2ClBr0.2, Li5.8Si0.1P0.9S4.5O0.2ClBr0.3, Li5.7Si0.1P0.9S4.4O0.2ClBr0.4, and Li5.6Si0.1P0.9S4.3O0.2ClBr0.5, respectively. Applicant discloses ([0087], TABLE 2, FIG. 1) that Embodiments 1–5 possess lattice constants of 9.8712 Å, 9.8746 Å, 9.8777 Å, 9.8813 Å, 9.8836 Å, respectively, thus demonstrating that the lattice constant of the oxysulfide-based compound increases as the content of Cl is constant and the content of Br increases. It can be reasonably interpreted, given the above, that the observed trend of an increasing lattice constant with a constant content of Cl and an increasing content of Br is an inherent property of oxysulfide-based compounds represented by the claimed Chemical Formula when X includes Cl and Br, due to the fact that Br, which has a larger ionic radius than S, is employed inside the structure of the oxysulfide-based compound to a greater extent as the content of Br increases. It is noted that observance of such a trend is well-known in the field of solid electrolytes based on the Li6PS5X lithium argyrodite family, as evidenced by Wang (p. 3835 ¶ “The long-range…” and FIG. 1d).
In comparison, modified Kim discloses the oxysulfide-based compound Li5.8+zP1.0−zSizS4.5O0.3ClBr0.2 where 0 < z ≤ 0.3 which satisfies the Chemical Formula of Claims 1 and 9 and is very similar to Embodiments 1–5 of the instant application.
MPEP § 2112.01.I states that 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 ether anticipation or obviousness has been established.
It is submitted that the oxysulfide-based compound of modified Kim is substantially identical to the oxysulfide-based compound of e.g. Embodiments 1–5 of the instant application, as set forth above, such that it would inherently possess the same properties, exhibit the same results, and thus anticipate the claimed limitation, i.e. within the content of the X, a lattice constant of the oxysulfide-based compound increases as the content of Cl is constant and the content of Br increases.
Assuming, arguendo, that the property recited in the claimed limitation is not anticipated, as there is no evidence on the record that any differences between the instantly claimed oxysulfide-based compound and that of modified Kim are critical, and as the conditions of the prior art significantly overlap the relevant conditions disclosed in the instant specification, it is submitted that prior to the effective filing date, one having ordinary skill in the art would have found the oxysulfide-based compound of modified Kim and that of the instant application to be obvious variants of one another.
Response to Arguments
Applicant’s arguments in the Remarks filed 19 December 2025 with regards to the 35 U.S.C. § 103 rejections made on the basis of the reference Kim et al. (WO 2019/107879 A1; US 2020/0381772 A1 used for translation and citation purposes) 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
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 JULIA MARIE FEHR, Ph.D. whose telephone number is (571)270-0860. The examiner can normally be reached Monday - Friday 9:00 AM - 5:00 PM EST.
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/J.M.F./Examiner, Art Unit 1725
/BASIA A RIDLEY/Supervisory Patent Examiner, Art Unit 1725