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 .
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.
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.
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, 3, and 5-9 are rejected under 35 U.S.C. 103 as being unpatentable over KR 10-2020-0061293 A (refer to equivalent US 2021/0242502 for paragraph numbers), both references of which were cited in the Information Disclosure Statement dated November 30, 2022, and further in view of CN 106784770 A, of which a complete copy of the Chinese document with an English abstract was provided with the Information Disclosure Statement dated November 4, 2024, and with a machine translation provided with the Office Action mailed March 19, 2026.
Regarding independent claim 1, KR ‘293 (US ‘502) discloses a lithium secondary battery (abstract; and paragraphs [0007]-[0012], [0019]-[0051], [0058]-[0069], and [0072]-[0081]; and claims 1, 5, and 11), in which the lithium secondary battery comprises the following components:
a positive electrode, a negative electrode, a separator, and an electrolyte,
wherein the negative electrode comprises a lithium-based metal, of which a lithium-magnesium (Li-Mg) alloy is one of many options listed as a lithium-based alloy (see paragraphs [0041] and [0062] of US ‘502), and
wherein the electrolyte comprises a furan-based solvent, a lithium salt, and an additive (see paragraphs [0019]-[0021], [0025], and [0032] of US ‘502).
Although several elements are among the group of which the lithium-based alloy would be formed (see paragraphs [0041] and [0062] of US ‘502), one of ordinary skill in the art would have recognized that selection of magnesium (Mg) as one of the elements to be used in combination with lithium (Li) to form a lithium-magnesium (Li-Mg) alloy would have been obvious to try with a reasonable expectation of success of forming an efficient lithium secondary battery with reduced lithium dendrite formation, thus improving lifetime characteristics (see paragraph [0012] of US ‘502).
In addition, KR ‘293 (US ‘502) discloses/suggests the features of independent claim 1, including that a thickness of a current collector of the negative electrode is within a range between 3 and 500 µm (see paragraph [0061] of US ‘502), but does not explicitly disclose that the Li-Mg alloy is a solid solution containing Mg in an amount of between 0 to 90 wt.%. However, one of ordinary skill in the art would have provided the Li-Mg alloy as a solid solution that covers the nearly complete range of Mg in the lithium-based alloy of between 0 to 90 wt.%, for the purpose of forming an efficient lithium secondary battery with reduced lithium dendrite formation, thus improving lifetime characteristics (see paragraph [0012] of US ‘502). Moreover, it would have been obvious to one of ordinary skill in the art at the time of the invention to choose the instantly claimed ranges through process optimization, since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. See In re Boesch, 205 USPQ 215 (1980).
KR ‘293 (US ‘502) does not disclose the limitation “in which Mg atoms are uniformly distributed in Li atoms without forming a separate intermetallic compound”, as well as the new limitation “a thickness of the negative electrode is more than 50 µm to 180 µm”.
However, CN ‘770 discloses a Li-Mg alloy of a secondary battery (abstract; pages 2 and 3 of translation under the heading “invention contents”; and Embodiment 1), in which the Li-Mg alloy is a magnesium lithium solid solution that is formed (in the four steps under Embodiment 1) of a lithium-magnesium alloy with uniform magnesium distribution in a surface thereof without forming a separate intermetallic compound (see steps 1 and 4 of Embodiment 1), as well as that a thickness of the negative electrode is between 200 and 1000 µm of the lithium-magnesium alloy comprising the magnesium lithium solid solution (see the 4th paragraph under the heading “invention contents” on page 2 of translation), for the purpose of obtaining a secondary battery having high specific capacity and cycle stability (see abstract; and the 3rd full paragraph on page 3 of translation).
It would have been obvious to one of ordinary skill in the art at the time the applicants’ invention was made to modify the Li-Mg alloy solid solution of the lithium secondary battery, as disclosed by KR ‘293 (US ‘502), by uniformly distributing Mg atoms in Li atoms without forming a separate intermetallic compound, as taught by CN ‘770, in order to obtain a secondary battery having high specific capacity and cycle stability (CN ‘770; abstract; and the 3rd full paragraph on page 3 of translation).
Moreover, in view of the combined teachings that KR ‘293 (US ‘502) discloses a thickness of a current collector of the negative electrode between 3 and 500 µm (see paragraph [0061] of US ‘502), and CN ‘770 discloses a thickness of the negative electrode is between 200 and 1000 µm of the lithium-magnesium alloy comprising the magnesium lithium solid solution, one of ordinary skill in the art would have recognized that the new claim 1 limitation “a thickness of the negative electrode is more than 50 µm to 180 µm” (at least an upper portion of this range) would have been attempted by routine experimentation by one of ordinary skill in the art with a reasonable expectation of success, for the purpose of obtaining increased specific capacity and cycle stability (CN ‘770; abstract; and the 3rd full paragraph on page 3 of translation). Although the claimed upper limit of 180 µm is somewhat below the lower limit of 200 µm disclosed by CN ‘770, and further in view of the wide range of between 3 and 500 µm (of the negative electrode current collector) disclosed by KR ‘293 (US ‘502), note that the courts have 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. Titanium Metals Corp. of America v. Banner, 778 F.2d 775, 783, 227 USPQ 773, 779 (Fed. Cir. 1985). In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955). In re Scherl, 156 F.2d 72, 74-75 (CCPA 1946). See MPEP 2144.05(I)(¶2).
Regarding claim 3, KR ‘293 (US ‘502) discloses that the lithium-based metal (Li-Mg alloy) is in the form of a foil (see paragraph [0063] of US ‘502).
Regarding claim 5, KR ‘293 (US ‘502) discloses that the furan-based solvent comprises one or more of furan and furan-based heterocyclic compounds set forth in paragraph [0025] of US ‘502.
Regarding claim 6, KR ‘293 (US ‘502) discloses that the lithium salt comprises one or more of LiCl, LiBr, LiI etc., as set forth in paragraph [0032] of US ‘502.
Regarding claim 7, KR ‘293 (US ‘502) discloses that the additive comprises one or more of lithium nitrate (LiNO3), potassium nitrate (KNO3), cesium nitrate (CsNO3) etc., as set forth in paragraph [0039] of US ‘502.
Regarding claim 8, KR ‘293 (US ‘502) discloses that the positive electrode comprises one or more of inorganic sulfur, an organic sulfur compound, and a carbon-sulfur polymer (see paragraph [0051] of US ‘502).
Regarding new claim 9, KR ‘293 (US ‘502) discloses that the furan-based solvent comprises one or more of furan and furan-based heterocyclic compounds set forth in paragraph [0025] of US ‘502, inclusive of 2-methylfuran (see the 3rd line of paragraph [0025)] and an ether-based solvent that includes dimethoxyethane (see the 5th line of paragraph [0035]).
Response to Arguments
The examiner acknowledges the applicants’ amendment received by the USPTO on June 17, 2026. Also, an Information Disclosure Statement dated May 27, 2026 has been considered and initialed, and a copy is provided with this Office Action. The applicants have amended independent claim 1, and have cancelled claim 4. Claims 1, 3, and 5-9 are currently under consideration in the application.
Applicants' arguments filed June 17, 2026 have been fully considered but they are not persuasive.
With regard to the applicants’ remarks/arguments on pages 4-6 of the amendment, the applicants argue that the combined teachings of KR ‘293 (US ‘502) and CN ‘770 fail to teach or suggest the new claim 1 limitation “wherein a thickness of the negative electrode is more than 50 µm to 180 µm”, and further states that the negative electrode current collector of KR ‘293 (US ‘502) is “in the thickness range of 3 to 500 µm”. Although the examiner agrees with this assessment, the applicants further state that CN ‘770 recites that “the Li-Mg alloy thickness is 200 µm to 1000 µm”, which is only somewhat above the claimed range of “more than 50 µm to 180 µm”. As a result of further analysis of these ranges by the examiner, the applicants are referred to the newly underlined portions and the new paragraph beginning with “Moreover” of the above 35 USC 103 rejection that set forth the obviousness of this range in consideration of the combined teachings. In view of the 35 USC 103 rejection (in particular in referring to the newly underlined portions and “Moreover” paragraph), and for these additional reasons, claims 1, 3, and 5-9 remain rejected.
Conclusion
THIS ACTION IS MADE FINAL. 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 KEVIN P KERNS whose telephone number is (571)272-1178. The examiner can normally be reached Monday-Friday 8am-430pm.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Keith Walker can be reached at (571)272-3458. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/KEVIN P KERNS/Primary Examiner, Art Unit 1735 June 25, 2026
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