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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 June 18, 2026 has been entered.
Summary
Applicant’s arguments and claim amendments submitted June 18, 2026 have been entered into the file. Currently, claims 2, 4-11, 15, and 19-21 are cancelled and claims 1 and 17 are amended, resulting in claims 1, 3, 12-14, and 16-18 pending for examination.
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.
Claims 12 and 17 are rejected under 35 U.S.C. 112(d) or pre-AIA 35 U.S.C. 112, 4th paragraph, 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.
Regarding claim 12, claim 12 recites that Salt B is lithium tetrafluoroborate, lithium hexafluorophosphate, or a combination thereof. However, claim 1 recites that Salt B comprises lithium tetrafluoroborate.
Regarding claim 17, claim 17 recites that the conductive agent can be graphite, expanded graphite, carbon spheres, carbon aerogel, polypyrrole, and polyaniline. However, these compounds of claim 17 do not further limit the compounds listed in claim 13.
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
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.
Claims 1, 3, 12-13, and 16-18 are rejected under 35 U.S.C. 103 as being unpatentable over Park-2 in view of Emerce, Kong, and Desilani.
Park-2 (US 2023/0163359 A1, previously prior art made of record and not relied upon in the Non-Final Office Action)
Emerce (Emerce, N. B. et al. Effect of Electrolyte-to-Sulfur Ratio in the Cell on the Li-S Battery Performance. Journal of the Electrochemical Society. 166, 8, A1490-A1500 (2019))
Kong (Kong, L. et al. Towards full demonstration of high areal loading sulfur cathode in lithium-sulfur batteries. Journal of Energy Chemistry. 39, 17-22 (2019))
Desilani (US 2016/0315350 A1)
Regarding claims 1, 3, and 12, Park-2 teaches an electrochemical energy storage device (lithium-sulfur battery, Park-2 Example 1) comprising a sulfur cathode (sulfur-carbon composite positive electrode active material, Park-2 Example 1), a metal anode (lithium metal negative electrode, Park-2 Example 1), a separator (polyethylene separator, Park-2 Example 1), and an electrolyte comprising a conducting salt (Salt A) at a concentration of 1 M (lithium bis(trifluoromethansulfonyl)imide, LiTFSI, Park-2 Example 1, a dissolving solvent (Solvent C) (dimethoxyethane, DME, Park-2 Example 1), and a diluent solvent (Solvent D) (1,1,2,2-tetrafluoroethyl 2,2,3,3-tetrafluoropropyl ether, TTE, Park-2 Example 1), wherein Solvent D and Solvent C are present at a volume ratio of 2.3 (7/3, Park-2 Example 1). Park-2 teaches the cathode having a loading amount of 4.0 mAh/cm2 (Park-2 [65]). Park further teaches that is it is possible and desirable to have a high loading amount of active material “even in a relatively small volume” (Park-2 [55]).
Park-2 does not teach the electrolyte containing an SEI engineering salt (Salt B) comprising lithium tetrafluoroborate.
Desilani teaches an electrolyte for a lithium sulfur battery, as taught by Park-2, that comprises a tetrafluoroborate salt at a concentration of 0.05 to 0.5 M and a lithium salt such as LiTFSI (Desilani [24-28]). Desilani further teaches that the tetrafluoroborate salt enhances cycle life of a lithium sulfur battery (Desilani [15]). Desilani teaches that lithium tetrafluoroborate (LiBF4) is a suitable tetrafluoroborate salt for use in the electrolyte of their invention (Desilani Example 2).
Since Park-2 and Desilani both teach electrolytes for lithium sulfur batteries and Desilani teaches adding 0.05 to 0.5 M tetrafluoroborate salt to an electrolyte comprising a lithium salt such as LiTFSI, that LiBF4 is a suitable tetrafluoroborate salt, and that the tetrafluoroborate salt enhances cycle life, it would have been obvious to someone of ordinary skill in the art before the effective filing date of the claimed invention to add 0.05 to 0.5 M LiBF4 to the electrolyte of Park-2 in order to enhance cycle life.
The LiBF4 concentration range of Desilani substantially overlaps the claimed range in the instant claim 1. It has been held that obviousness exists where the claimed ranges overlap or lie inside ranges disclosed by the prior art. See MPEP 2144.05 (I). Therefore, it would have been obvious to someone of ordinary skill in the art before the effective filing date of the claimed invention to have selected from the overlapping portion of the range taught by Desilani, because overlapping ranges have been held to establish prima facie obviousness.
Park-2 is silent regarding the areal active material loading (mg/cm2) and electrolyte to sulfur ratio (µL/mg) of Example 1.
Kong teaches lithium-sulfur batteries, as taught in Park-2, and that tuning parameters such as the size of the composite cathode and separator composition can improve performance of the battery and sulfur utilization (Kong pg. 18 left column). Kong further teaches that it is desirable to have high areal sulfur loading in order to obtain lithium-sulfur batteries with high energy density (Kong pg. 19 right column) and that a sulfur loading of 4.5 mg/cm2 is desirable (Kong abstract).
Since Park-2 teaches that it is desirable to have high loading of active material and Kong teaches that high areal loading of sulfur is desired and that components of the battery, such as the electrolyte and separator, can be chosen to obtain optimal performance according to the cathode material and areal loading being used, it would have been obvious to someone of ordinary skill in the art before the effective filing date of the claimed invention to fabricate the electrochemical energy storage device of Park-2 wherein the areal active material loading of the cathode is within the claimed ranges of about 2.5 mg/cm2 or greater (instant claim 1) and about 2.5 mg/cm2 to about 20.0 mg/cm2 (instant claim 2) in order to obtain an electrochemical energy storage device with suitable performance for a desired application.
Emerce teaches the electrolyte-to-sulfur ratio impacts the performance of lithium-sulfur batteries (Emerce Abstract) and that the ratio may be tuned to achieve improved specific energy and energy density (Emerce Conclusions). Emerce further teaches that there is a ratio value above which the improvements are no longer observed (Emerce Conclusions).
Since Park-2 and Emerce teach lithium-sulfur batteries and Emerce teaches that tuning the electrolyte-to-sulfur ratio can impact battery performance, it would have been obvious to someone of ordinary skill in the art before the effective filing date of the claimed invention to tune the electrolyte-to-sulfur ratio of the electrochemical energy storage device of Park-2, including amounts within the claimed ranges of about 10.0 µL/mg or less (instant claim 1) and about 10.0 µL/mg to about 0.5 µL/mg (instant claim 3), in order to achieve an electrochemical energy storge device with suitable specific energy and energy density for a desired application.
Regarding claims 13 and 17, Park-2 in view of Emerce, Kong, and Desilani teaches all features of claim 1, as described above. Park-2 further teaches the sulfur cathode comprising a sulfur/carbon electrochemical active composite (sulfur-carbon composite, Park-2 Example 1), carbon black as a conductive agent (Denka black, Park-2 Example 1), and a binder that is a combination of carboxy methyl cellulose and styrene butadiene rubber (Park-2 Example 1).
Regarding claim 16, Park-2 in view of Emerce, Kong, and Desilani teaches all features of claim 1, as described above. Park-2 further teaches the binder being a combination of carboxymethyl cellulose and styrene butadiene rubber with a weight ratio of 0.43 (SBR:CMC = 7:3, CMC/SBR = 3/7 = 0.43, Park Example 1).
It has been held that a prima facie case of obviousness exists where the claimed ranges or amounts do not overlap with the prior art but are merely close. See MPEP 2144.05 (I).
Therefore, it would have been obvious to someone of ordinary skill in the art before the effective filing date of the claimed invention to have chosen a combination of CMC and SBR binders wherein the ratio of CMC to SBR is within the claimed range of about 0.5 to about 5, because ranges that are merely close have been held to establish prima facie obviousness.
The examiner notes that the instant specification recites “approximately or about can mean up to plus or minus 10% of the particular term” (instant specification [38]).
Regarding claim 18, Park-2 in view of Emerce, Kong, and Desilani teaches all features of claim 1, as described above. Park-2 further teaches the metal anode comprising lithium (Park-2 Example 1, lithium metal).
Claim 14 is rejected under 35 U.S.C. 103 as being unpatentable over Park-2 in view of Emerce, Kong, and Desilani, as applied to claims 1 and 13 above, and in further view of Xu (Xu, G. et al. Selenium and Selenium-Sulfur Chemistry for Rechargeable Lithium Batteries: Interplay of Cathode Structures, Electrolytes, and Interfaces. ACS Energy Letters. 2, 605-614 (2017)).
Regarding claim 14, Park-2 in view of Emerce, Kong, and Desilani teaches all features of claims 1 and 13, as described above. Park-2 teaches the use of a sulfur-carbon composite in the cathode (Park-2 Example 1). However, Park-2 does not teach the active material being a selenium-sulfur/carbon composite.
Xu teaches that using active material comprising selenium in addition to sulfur can result in higher electronic conductivity than using only sulfur, thus enabling “a higher loading of active material in the electrode” and an increase in the overall energy density (Xu pg. 611 right column last paragraph). Xu teaches that selenium and selenium-sulfur cathode materials are desirable for use in rechargeable batteries due to the high electronic conductivity and high volumetric capacity of selenium. Xu further provides examples of cathode materials comprising selenium, sulfur, and carbon (Xu Table 2; Fig. 3a).
Since Xu teaches that the addition of selenium to cathode active materials can improve electronic conductivity and battery performance, it would have been obvious to someone of ordinary skill in the art before the effective filing date of the claimed invention to add selenium (Se) to the cathode of Park-2 in order to improve electronic conductivity and battery performance.
Adding any amount of Se to the cathode composite material of Park-2 (sulfur-carbon composite, Park Example 1) would result in a material comprising sulfur, selenium, and carbon, which would inherently result in x > 0, y > 0, 0 < p ≤ 100 (p greater than 0), 0 ≤ q < 100, p + q = 100, wherein x, y, p, and q are weight percentage values.
Response to Arguments
Response – Specification Objections
The objection due to trade names is overcome by applicant’s amendments to the specification in the response received June 18, 2026. The objection to the specification is withdrawn.
Response – Claim Rejections 35 USC § 112
The rejection of claim 17 under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention is overcome by applicant’s amendments to claim 17 in the response received June 18, 2026. This rejection of claim 17 is withdrawn.
Response – Claim Rejections 35 USC § 103
Applicant’s arguments filed June 18, 2026 have been fully considered and are not persuasive.
Applicant’s arguments with respect to claim 1 and the Seung reference 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.
On pages 9-10 of the response, Applicant appears to allege that the claimed invention yields unexpected results. Applicant appears to allege that the unexpected results stem from the specific salt used and the concentration of said salt.
It is noted that it is the burden of Applicant to provide evidence that establishes that the differences in results are in fact unexpected and unobvious and of both statistical and practical significance. See MPEP 716.02(b)(I). Applicants have the burden of explaining proffered data. See MPEP 716.02(b)(II). It is further noted that in order to establish unexpected results over a claimed range, Applicants should compare a sufficient number of tests both inside and outside the claimed range to show the criticality of the claimed range. See MPEP 716.02(d) II. Additionally, the claims must be commensurate in scope with the proffered data to provide a nexus between the claims and the data establishing evidence of unexpected results. See MPEP 716.02(d).
The data presented in the instant disclosure and remarks received June 18, 2026 do not appear to be commensurate in scope with independent claim 1 and do not appear to compare a sufficient number of tests both inside and outside the claimed ranges.
Claim 1 requires that Salt A be selected from a group of compounds; however, the data presented in the instant disclosure only include LiTFSI. Additionally, claim 1 claims the concentration of Salt A being about 1 M to 5 M; however, only a single concentration for Salt A (1.6 M) is used in the data presented in the instant disclosure.
Claim 1 claims the concentration of Salt B being about 0.02 M to 0.1 M; however, only concentrations of 0 M, 0.05 M, 0.1 M, and 0.15 M are used in the data presented in the instant disclosure (Fig. 4). Specially, there is no data presented between 0 M and 0.02 M to support the unexpected result associated with the endpoint of 0.02 M in the claimed range.
On page 9 of the response, Applicant states that “the capacity of the 0 M LiBF4 is worst” and that a concentration of 0.15 M and greater results in capacity retention that is worse relative to cells with 0.05 M and 0.1 M.
The Examiner respectfully disagrees. Instead of 0 M, as alleged by Applicant, the data in Fig. 4 (drawings filed September 28, 2022) show that a concentration of 0.15 M results in the “worst” performance (specific capacity and coulombic efficiency). Additionally, the data in Fig. 4 shows that a concentration of 0.1 M yields lower specific capacity and coulombic efficiency than 0 M, thus an electrolyte without LiBF4 results in better performance relative to an electrolyte having a LiBF4 concentration of 0.1 M, which is a concentration within the claimed range for Salt B.
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Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
Song (US 2023/0140648 A1): appears to disclose an electrolyte solution for lithium-sulfur batteries (abstract) comprising LiTFSI, acetonitrile, and TTE (Preparation Example 1). Song appears to further disclose a lithium-sulfur battery comprising the electrolyte, styrene butadiene rubber (SBR) and carboxymethyl cellulose (CMC) as binders, Denka black conductive agent, and a sulfur-carbon composite (Example 1).
Cao (US 20220115706 A1): appears to disclose an electrolyte for lithium ion batteries comprising lithium bis(fluorosulfonyl)imide (LiFSI), 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether (TTE), ethylene carbonate (EC), and lithium hexafluorophosphate LiPF6 (Table 23, Electrolyte LHCE-34).
Kim (US 2003/0073005 A1): appears to disclose adding a lithium salt such as LiBF4 at a concentration of 0.05 to 1.5 M to an electrolyte in a lithium sulfur battery (Kim [34]).
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JULIA S CASERTO whose telephone number is (571)272-5114. The examiner can normally be reached 7:30 am - 5 pm ET.
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/J.S.C./Examiner, Art Unit 1789
/MARLA D MCCONNELL/Supervisory Patent Examiner, Art Unit 1789
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