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 .
Status of the claims
This is the second non-final office action. Upon further search, new art has been identified and applied, as described below. Claims 1 and 9 have been amended and claims 1 and 5-12 are pending.
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.
Claim(s) 1, 6-10, and 12 are rejected under 35 U.S.C. 103 as being unpatentable over Sun, et al (Journal of Materials Chemistry A, 2019, 7, 17782) in view of Chen et al (ACS Omega 2019, 4, 20708-20714) and Yu (20150255771 A1).
In reference to claim 1, Sun discloses a carbonate electrolyte (abstract) comprising:
A lithium salt, wherein the lithium salt (abstract and page 17783, second column) comprises:
0.8 M LiTFSI (corresponds to the first salt)
0.2 M LiDFOB (corresponds to the second salt)
0.05 M LiPF6 (corresponds to the third salt)
The overall concentration of the salt is therefore 1.05 M (0.8 M LiTFSI + 0.2 M LiDFOB +0.05 M LiPF6).
A solvent of EMC:FEC (corresponds to a carbonate solvent).
While the first, second, and third lithium salt concentrations and the overall lithium salt concentration are close to those currently claimed, they do not fall within the claimed range.
However, Sun discloses that the composition of the SEI layer profoundly affects the deposition morphology of the lithium, as seen in Figure 2, wherein increasing the ratio of LitFSI with respect to LiDFOB resulted in an improved lithium deposition morphology (page 17785, first column). LiTFSI was the main salt of choice as it introduces species that contribute to important SEI features and LiDFOB was added to further strengthen the SEI layer. The LiPF6 salt was mixed in as an additive to prevent Al corrosion (page 17783, first column). Sun suggests that increasing the content of these species could better stabilize and preserve lithium metal for superior performance (conclusion). Therefore, Sun acknowledges that the balance of the three salts and their final concentrations play a critical role in increasing performance of the battery.
It is recognized in the battery art that conductivity and viscosity of the electrolyte solution play important roles in battery performance. This is exemplified by Chen (abstract) and Yu ([36, 42]). Chen discloses that as lithium salt concentrations in the electrolyte increase, the viscosity increases, which slows down the absorption and desorption of lithium (Page 20710, first column). Chen also discloses that optimizing lithium salt concentration leads to greater capacities and cyclability (introduction). Therefore, Chen discloses that the viscosity and concentration of the lithium salt need to be balanced to increase battery performance. Yu discloses that if the concentration of lithium salts is too low the ionic conductivity of the solution decreases and if the concentration is too high ionic conductivity decreases and this increases viscosity such that it is unable to wet the separator [42]. Further, Yu ties the viscosity of the electrolyte solution to the safety and performance of the battery [32].
Therefore, it would have been obvious to one of ordinary skill in the art to have modified the electrolyte of Sun to increase and optimize the concentration of the lithium salts while balancing the ratio of those three salts in order to increase/optimize the overall concentration of each type of salt, while balancing the viscosity to improve the battery performance, as described above. This modification would have been within the ambit of the ordinary artisan, as Sun explicitly states that it would have been obvious to increase the salt species and Chen and Yu disclose the known tension between balancing viscosity and concentration in lithium salt electrolytes in order to optimize the concentration of the salts to optimize battery performance. It is the Examiner’s position that this routine optimization would have led one of ordinary skill in the art at the time the instant invention was filed to have arrived at concentrations of the three salts (and overall concentration) that meet the claimed values, without undue experimentation.
In reference to claim 6, Sun discloses that the carbonate solvent includes ethyl methyl carbonate (EMC) and fluoroethylene carbonate (FEC), as described above (corresponds to the carbonate solvent comprises EMC and FEC).
In reference to claims 7 and 8, Sun discloses that the carbonate solvent includes ethyl methyl carbonate (EMC) and fluoroethylene carbonate (FEC) in a ratio of EMC:FEC = 3:1 v/v, which is 75 vol% EMC and 25 vol% FEC.
In reference to claim 9, Sun discloses that the electrolyte described in claim 1, above is incorporated into a lithium secondary battery (supplemental information) comprising:
An aluminum cathode with NCM622 cathode active material
An anode comprising lithium metal
A celgard separator between the cathode and anode
The electrolyte of claim 1 is incorporated into the separator, as they are formed into the battery and are in contact with one another.
In reference to claim 10, Sun discloses that the cathode active material comprises Li[Ni0.59Co0.2Mn0.2Al0.1]O2 (NCM622-Al 1%) (abstract and supplemental information) (corresponds to a combination of the lithium manganese and lithium aluminum oxides claimed).
In reference to claim 12, the limitations of claim 12 further limit an optional limitation from claim 9. As Sun teaches lithium metal as the anode material, Sun is not required to teach the option limitations of claim 12. Therefore claim 12 is rejected based on the claim reciting only optional limitations. If Applicant wishes for claim 12 to be non-optional, the Examiner suggests reciting that, for example, “wherein the anode comprises a lithium metal alloy and the lithium metal alloy comprises…”.
Claim 5 is rejected under 35 U.S.C. 103 as being unpatentable over Sun, et al (Journal of Materials Chemistry A, 2019, 7, 17782) in view of Chen et al (ACS Omega 2019, 4, 20708-20714) and Yu (20150255771 A1) and further in view of Cho (US 20180331393 A1).
In reference to claim 5, Sun teaches that the first salt is LITFSI and the second salt is LiDFOB, as described above. Sun does not specifically teach that that first salt is LiFSI. However, Cho teaches a similar electrolyte composition [14] to Sun, where the first salt is taught to be suitably LiFSI or LiTFSI in combination with LiDFOB and LiPF6 [14], as in Sun. Therefore, it would have been obvious to one of ordinary skill in the art to modify the composition of modified Sun by substituting the LiTFSI with LiFSI, as they are taught to be known interchangeable species in the three-salt mixture, as in Sun and Cho. The selection of a known material is prima facie obvious.
Claim 11 is rejected under 35 U.S.C. 103 as being unpatentable over Sun, et al (Journal of Materials Chemistry A, 2019, 7, 17782) in view of Chen et al (ACS Omega 2019, 4, 20708-20714) and Yu (20150255771 A1) and further in view of Tiruvannamalai (US 20260233549 A1).
In reference to claim 11, Sun teaches that the anode is lithium metal, as described above. However, Sun is silent as to the thickness of the foil. Tiruvannamali discloses that lithium-ion battery anodes formed of lithium foil are suitable 0.1 to about 100 microns thick [37]. Therefore, it would have been obvious to one of ordinary skill in the art to form the foil of Sun to have a thickness of 0.1 to 100 microns in order to provide a suitable thickness of a lithium foil anode in a battery.
Response to Arguments
Applicant's arguments filed 12/11/2025 have been fully considered but they are not found to be persuasive. The Examiner notes that new art has been applied, but Applicant’s arguments regarding the criticality are addressed with respect to the new applied references.
Applicant argues that the asserted effects, demonstrated by the present invention, are only exhibited when the concentration of the respective salts form a critical combination.
Applicant argues specifically that viscosity in Examples 1-3 increases, but that the ionic conductivity was not decreased too much (Table 2-3 and Figure 2-3, pages 6-7 of arguments).
This argument is not found to be persuasive, as it is well known in the art, as described above in the rejection of claim 1, that the ordinary artisan must balance the viscosity and conductivity in the electrolyte in order to optimize the battery performance. Therefore, an ordinary artisan would have optimized the electrolyte to balance those properties, as described above. Applicant has not provided a showing of criticality, as the trends provided are what is expected in the art, as described above. Further the data provided are not commensurate in scope with the claims, as these data provided is for a specific combination of salts in a specific concentration, among other aspects.
Applicant argues on page 8 that Example 2 has similar electrodeposition to comparative example 6, rather than non-uniform electrodeposition caused by lowered ionic conductivity.
These arguments are not found to be persuasive, as it is not clear from the images what the structural differences are between the two samples. Also, there is no quantitative data provided to determine the differences between the two types of deposition. A singular SEM at two magnifications does not appear to be useful to determine the overall differences among the two samples, particularly when there isn’t any grain size or statistical analysis of the samples. Additionally, these arguments are not commensurate in scope with the claims. Further, Applicant has not persuasively argued that these results are unexpected.
Applicant appears to argue on page 9 that Figure 6 shows that comparative example 6 and example 2 are superior to the comparative examples having a single composition of LiTSFI.
The Examiner notes that Sun specifically teaches the same composition as Comparative Example 6. Applicant merely argues that Example 2 also exhibited increased capacity. Applicant does not assert any unexpected results over Comparative Example 6. It is also noted that these arguments are not commensurate in scope with the claims.
Applicant argues on pages 10 and 11 that Electrolytes Examples 1 and 2 have increased capacity of Comparative Example 6 on the 80th cycle.
The examiner does not find these arguments to be persuasive, as cycling performance is a known results effect variable based on electrolyte concentration, See Chen Figure 6. It would have been obvious to one of ordinary skill in the art based on the teachings of the references described above to optimize the concentration of the lithium salts in order to improve the properties of the battery, including cycling performance. Therefore, it is not deemed unexpected that an optimal concentration of lithium salt in the electrolyte exists and it would have been within the ambit of an ordinary artisan to increase/optimize the salt concentration, as is suggested by Sun in order to determine that optimal concentration. Further, it is noted that this evidence is not commensurate in scope with the claims.
ON pages 11 and 12 Applicant argues that the lifespan characteristics depend on salt concentration and cites comparative examples 1-4.
The Examiner notes that comparative examples 1-4 contain only 2 of the lithium salts. It is the Examiner’s position that this comparison is moot, as the prior art of Sun discloses all three required lithium salts. Further, it is not deemed unexpected that an optimal concentration of lithium salt in the electrolyte exists and it would have been within the ambit of an ordinary artisan to increase/optimize the salt concentration, as is suggested by Sun in order to determine that optimal concentration.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to MARLA D MCCONNELL whose telephone number is (571)270-7692. The examiner can normally be reached M-F 9 AM - 5PM.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Sri Kumar can be reached at (571) 272-7769. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/MARLA D MCCONNELL/Supervisory Patent Examiner, Art Unit 1789
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