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 .
Summary
Applicant’s arguments and claim amendments submitted July 2, 2026 have been entered into the file. Currently, claims 1, 7, 10, 13, 19, and 20 are amended, claims 21 and 22 are new, and claims 6 and 18 are cancelled without prejudice or waiver, resulting in claims 1-5, 7-17, and 19-22 pending for examination.
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 1-2, 4-5, 7, 10, 13-14, 16-17, and 20 are rejected under 35 U.S.C. 103 as being unpatentable over Zheng (Zheng, Q., Yamada, Y., Shang, R. et al. A cyclic phosphate-based battery electrolyte for high voltage and safe operation. Nat Energy 5, 291–298 (2020)) and further in view of Kim (WO2021167428A1; US20230095613A1 used for purposes of translation).
Regarding claims 1 and 13, Zheng teaches:
A battery that cycles lithium ions (Zheng, abstract), the battery comprising:
a positive electrode comprising an electroactive material comprising a layered lithium transition metal oxide (Zheng teaches a layered lithium transition metal oxide as the cathode material; LiNi1/3Mn1/3Co1/3O2 (NMC) and LiNi0.5Mn1.5O4 (LNMO), pg. 292, column 1, paragraph 2, lines 13-16);
For claim 13 only: a negative electrode comprising an electroactive material comprising silicon oxide, lithiated silicon oxide, graphite, or a combination thereof (Zheng teaches graphite as the anode material, pg. 297, column 1, “Electrode preparation” paragraph, lines 6-8);
and an electrolyte infiltrating the positive electrode (for claim 1) and the negative electrode (for claim 13 which requires infiltration into both electrodes), (Zheng teaches a positive electrode and negative electrode in contact with an electrolyte featuring a TFEP solvent that (1) forms a stable SEI interface on the anode (graphite) which achieved stable cycling, and (2) forms a CEI layer on the cathode (LNMO/NMC) to prevent oxidation and dissolution, which inherently requires infiltration into both electrode structures; pg. 297, “Conclusions” paragraph),
the electrolyte comprising: an organic solvent, a lithium salt, and a fluorinated phosphate ester additive (Zheng, LiFSI salt is dissolved in TFEP/FEMC; TFEP represents the fluorinated phosphate ester additive; pg. 292, column 2, paragraph 2, lines 1-3),
the fluorinated phosphate ester additive comprising at least one of: (i) a chemical compound comprising a phosphate group attached to two or three branched-chain fluorocarbon groups (Zheng, FTEP is listed as fluorinated phosphate ester additive in Fig. 1),
or (ii) a chemical compound comprising a cyclic phosphate group attached to a fluorocarbon group (Zheng, TFEP in Fig. 1).
However, Zheng does not appear to disclose an electrolyte comprising greater than 70%, by weight, of a mixture of a cyclic carbonate and a linear carbonate, and 0.5% to 2.5%, by weight, of a fluorinated phosphate ester additive.
Kim discloses a non-aqueous electrolyte for a lithium secondary battery comprising a lithium salt, organic solvent, and a fluorinated additive (claim 1). Kim further discloses that the non-aqueous electrolyte may further include fluorinated additives such as the compound represented by Chemical Formula 1 (claim 1) and supplementary additives such as fluorinated phosphate-based compounds, with some examples that are similar to the claimed fluorinated additive (tris(2,2,2-trifluoroethyl) phosphate; [0058] and [0062]). Kim teaches that the supplementary additives in particular, are included in order to prevent a decomposition of the non-aqueous electrolyte and a collapse of the negative electrode under a high-output environment, or to improve low-temperature high-rate discharge characteristics, high-temperature stability, overcharge-preventing effect, battery swelling-inhibiting effect at high temperature, or the like ([0057]).
Regarding the content of the supplementary additives and the compound represented by Chemical Formula 1, Kim discloses the content of the supplementary additives may be 0.01-50 wt%, and particularly 0.01-20 wt%, based on the total weight of the non-aqueous electrolyte ([0069]) and that the fluorinated additive represented by Chemical Formula 1 (claim 1) is present in an amount of 0.1-wt % to 2 wt %, which both overlap with the claimed range of 0.5% to 2.5%, by weight. Further, for the supplementary additives, Kim notes that when the content of the supplementary additives is less than 0.01 wt %, it is not possible to obtain sufficient effects of improving the low-temperature output, high-temperature storage characteristics and high-temperature life characteristics of a battery. Conversely, when the content of the supplementary additives is larger than 50 wt%, excessive side reactions may occur during the charge/discharge of a battery due to an excessive amount of additives ([0069]). For the content of the other disclosed fluorinated additive compounds, such as the fluorinated compound represented by Chemical Formula 1, it is worth noting that Kim teaches when the compound is used within the disclosed range of 0.1 wt% to 2 wt%, it is possible to similarly obtain overall improved battery performance while maintaining undesirable side reactions ([0053]).
Therefore, in terms of the wt% of the fluorinated phosphate-based supplementary additives of Kim which are similar to the claimed fluorinated additive(s), it would have been obvious to someone of ordinary skill in the art before the effective filing date of the claimed invention to further modify the electrolyte of Zheng by using a content range of 0.01-50 wt%, and particularly 0.01-20 wt%, for fluorinated phosphate-based supplementary additive as taught by Kim, in order to improve battery performance while preventing an excessive amount of side reactions that may occur during charging and discharging. Accordingly, when the prior art discloses a general range that overlaps or routinely encompasses the claimed range, a prima facie case of obviousness is established (see MPEP §2144.05).
Regarding the solvents in the electrolyte, Kim explicitly teaches the organic solvent may include a cyclic carbonate-based organic solvent, a linear carbonate-based organic solvent or a mixed organic solvent thereof ([0041]). Kim further teaches that the cyclic carbonate-based organic solvent is a high-viscosity organic solvent capable of dissociating the lithium salt well in the electrolyte, such as ethylene carbonate (EC) ([0042]), and the linear carbonate-based organic solvent has low viscosity and a low dielectric constant such as diethyl carbonate (DEC) ([0043]). In terms of the wt% of the organic solvent mixture in the electrolyte, in view of the values/ranges of the lithium salt, carbonates, and additional additives, the non-aqueous organic solvent mixture makes up the vast majority of the formulation weight, specifically greater than 70% by weight of the overall electrolyte composition (Example 2, a total of the carbonate compounds is ~84 wt% based on the overall electrolyte composition, [0115]-[0117]).
Therefore, it would have been obvious to someone of ordinary skill in the art before the effective filing date of the claimed invention to further modify the electrolyte of Zheng to comprise a mixture of a cyclic carbonate and a linear carbonate, as taught by Kim, in order to achieve the known benefits of thermal, mechanical, and electrochemical stability under high-output conditions. Regarding the wt% of the cyclic and linear carbonate mixture in the electrolyte, it would have further been obvious to someone of ordinary skill in the art before the effective filing date of the claimed invention to utilize the content amount of Kim, because when the prior art discloses a general range that overlaps or routinely encompasses the claimed range, a prima facie case of obviousness is established (see MPEP §2144.05).
Regarding claim 2, modified Zheng teaches all features of claim 1 as described above. Zheng further teaches that the fluorinated phosphate ester additive comprises a fluorinated phosphate triester having the formula (1):
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where X1, X2, X3, X4, X5, and X6 are each individually a fluorocarbon group, R1, R2, R3, R4, R5, and R6 are each individually a fluorinated or unfluorinated bivalent hydrocarbon group, and Y1, Y2, and Y3 are each individually hydrogen (H) or fluorine (F) (Zheng, FTEP in Fig. 1).
Regarding claim 4, modified Zheng teaches all features of claim 1 as described above. Zheng further teaches that the fluorinated phosphate ester additive comprises a fluorinated cyclic phosphate ester having the formula (2):
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where R1 is an unfluorinated bivalent hydrocarbon group, R2 is a fluorinated or unfluorinated bivalent hydrocarbon group, and X is a fluorocarbon group (Zheng, EP and TFEP in Fig. 1).
Regarding claim 5, modified Zheng teaches all features of claim 4 as described above. Zheng further teaches that the fluorinated phosphate ester additive comprises 2-(2,2,2-trifluoroethoxy)-1,3,2-dioxaphospholane 2-oxide (Zheng, TFEP; pg. 292, column 1, paragraph 2, lines 1-6).
Regarding claim 7, modified Zheng teaches all features of claim 1 as described above. Zheng further teaches a lithium-ion battery and electrolyte wherein the electroactive material of the positive electrode comprises a layered lithium- and manganese-rich transition metal oxide (Zheng, pg. 292, column 1, paragraph 2), and wherein the organic solvent comprises fluoroethylene carbonate (FEC) (Zheng, Fig. 1).
However, Zheng does not teach that the electrolyte comprises a mixture of both fluoroethylene carbonate (FEC) and diethyl carbonate (DEC).
Kim teaches a non-aqueous electrolyte for a lithium secondary battery comprising an organic solvent which may include a cyclic carbonate-based organic solvent, a linear carbonate-based organic solvent or a mixed organic solvent thereof ([0041]). Kim further teaches that the cyclic carbonate-based organic solvent is a high-viscosity organic solvent capable of dissociating the lithium salt well in the electrolyte, and the linear carbonate-based organic solvent has low viscosity and a low dielectric constant such as diethyl carbonate (DEC) ([0043]). Kim teaches the non-aqueous electrolyte may further comprise supplementary additives, such as cyclic carbonate-based compounds including fluoroethylene carbonate (FEC) ([0058]-[0059]), in order to prevent a decomposition of the non-aqueous electrolyte and a collapse of the negative electrode under a high-output environment, or to improve low-temperature high-rate discharge characteristics, high-temperature stability, overcharge-preventing effect, battery swelling-inhibiting effect at high temperature, or the like ([0057]).
Therefore, it would have been obvious to someone of ordinary skill in the art before the effective filing date of the claimed invention to further modify the electrolyte of Zheng to include a cyclic carbonate-based compound such as fluoroethylene carbonate (FEC) and a linear carbonate-based compound such as diethyl carbonate (DEC), as taught by Kim, in order to achieve the known benefits of improved thermal, mechanical, and electrochemical stability under high-output conditions.
Regarding claim 10, modified Zheng teaches all features of claim 1 as described above. Zheng further teaches the electroactive material of the positive electrode comprises a layered lithium nickel-rich transition metal oxide (Zheng teaches a layered lithium nickel-rich transition metal oxide as the cathode material; LiNi1/3Mn1/3Co1/3O2 (NMC) and LiNi0.5Mn1.5O4 (LNMO), pg. 292, column 1, paragraph 2, lines 13-16). Zheng additionally teaches the electrolyte may be ethylene carbonate (EC) which is cyclic carbonate or dimethyl carbonate (DMC) which is a linear carbonate (Zheng, Fig. 2).
However, Zheng does not expressly teach the electrolyte comprises the fluorinated phosphate ester additive, a lithium salt, and wherein the electrolyte comprises a mixture of ethylene carbonate (EC) and dimethyl carbonate (DMC).
Kim teaches a non-aqueous electrolyte for a lithium secondary battery comprising an organic solvent which may include a cyclic carbonate-based organic solvent, a linear carbonate-based organic solvent or a mixed organic solvent thereof ([0041]). Kim further teaches that the cyclic carbonate-based organic solvent is a high-viscosity organic solvent capable of dissociating the lithium salt well in the electrolyte such as ethylene carbonate (EC), and the linear carbonate-based organic solvent has low viscosity and a low dielectric constant such as dimethyl carbonate (DMC) ([0043]).
Therefore, it would have been obvious to someone of ordinary skill in the art before the effective filing date of the claimed invention to further modify the electrolyte of Zheng to include a mixture of ethylene carbonate (EC) which is a cyclic carbonate and dimethyl carbonate (DMC) which is a linear carbonate, as taught by Kim, in order to achieve suitable lithium salt dissociation and viscosity properties for the electrolyte.
Regarding claim 14, modified Zheng teaches all features of claim 13 as described above. Zheng further teaches that the fluorinated phosphate ester additive comprises a fluorinated phosphate triester having the formula (1):
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where X1, X2, X3, X4, X5, and X6 are each individually a fluorocarbon group, R1, R2, R3, R4, R5, and R6 are each individually a fluorinated or unfluorinated bivalent hydrocarbon group, and Y1, Y2, and Y3 are each individually hydrogen (H) or fluorine (F) (Zheng, FTEP in Fig. 1).
Regarding claim 16, Zheng teaches all features of claim 13 as described above. Zheng further teaches that the fluorinated phosphate ester additive comprises a fluorinated cyclic phosphate ester having the formula (2):
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where R1 is an unfluorinated bivalent hydrocarbon group, R2 is a fluorinated or unfluorinated bivalent hydrocarbon group, and X is a fluorocarbon group (Zheng, EP and TFEP in Fig. 1).
Regarding claim 17, Zheng teaches all features of claim 16 as described above. Zheng further teaches that the fluorinated phosphate ester additive comprises 2-(2,2,2-trifluoroethoxy)-1,3,2-dioxaphospholane 2-oxide (Zheng, TFEP; pg. 292, column 1, paragraph 2, lines 1-6).
Claims 3, 8-9, and 11-12 are rejected under 35 U.S.C. 103 as being unpatentable over Zheng and Kim as applied to claim 1 above, and further in view of Ji (US20200388882A1).
Regarding claim 3, modified Zheng teaches all features of claim 2 as described above, but does not disclose that the fluorinated phosphate ester additive comprises tris(1,1,1,3,3,3-hexafluoropropan-2-yl) phosphate, tris(1,1,1,5,5,5-hexafluoropentan-3-yl) phosphate, tris(1,1,1,2,3,3,3-heptafluoropropan-2-yl) phosphate, or a combination thereof.
Ji teaches a lithium-ion battery and an electrolyte comprising a fluorinated additive compound comprising tris(1,1,1,3,3,3-hexafluoropropan-2-yl) phosphate (Ji, specification, [0067], [0184]). Ji further teaches that including fluorinated electrolyte additives into electrolyte solutions enhances the thermal stability of the electrolyte and improves the overall electrochemical performance and safety of the battery due to their beneficial flame resistance and fire-retardant properties (Ji, specification, [0042]).
Therefore, it would have been obvious to someone of ordinary skill in the art before the effective filing date of the claimed invention to further modify the electrolyte composition of Zheng to include a fluorinated electrolyte additive compound comprising tris(1,1,1,3,3,3-hexafluoropropan-2-yl) phosphate, as taught by Ji, because such additives were known to improve lithium-ion battery performance in terms of flammability and safety. Such modification would have involved the use of known electrolyte additives to perform the same function of improving the battery in a predictable manner.
Regarding claim 8, modified Zheng teaches all features of claim 7 as described above, including an electrolyte comprising a fluorinated phosphate ester additive, a lithium salt, and mixture of a cyclic carbonate and a linear carbonate. Zheng further teaches that the lithium salt may include lithium hexafluorophosphate (LiPF6) (Zheng, Fig. 2). However, Zheng does not expressly disclose a battery wherein the electrolyte comprises both lithium hexafluorophosphate (LiPF6) and lithium difluorophosphate (LiPO2F2).
Ji discloses a fluorinated electrolyte comprising at least one fluorinated electrolyte additive compound comprising a phosphate, a Li salt compound, and/or a fluorine salt compound (claim 1). Ji further discloses the electrolyte comprises a lithium salt comprising lithium hexafluorophosphate (LiPF6), and further discloses the electrolyte may further comprise lithium difluorophosphate (LiPO2F2) (Ji, specification, [0061]-[0063]).
Therefore, it would have been obvious to someone of ordinary skill in the art before the effective filing date of the claimed invention to further modify the electrolyte of Zheng to include lithium hexafluorophosphate (LiPF6) and lithium difluorophosphate (LiPO2F2) in addition to the fluorinated phosphate compound, as taught by Ji, because Ji teaches that such electrolyte additives are suitable for use in lithium-ion battery electrolytes and provide improved battery performance (Ji, specification, [0055]).
Regarding claim 9, modified Zheng teaches all features of claim 8 as described above, which further includes lithium difluorophosphate (LiPO2F2) in the electrolyte. However, Zheng does not expressly teach a lithium-ion battery electrolyte wherein:
the fluorinated phosphate ester additive constitutes, by weight, greater than or equal to about 0.5% to less than or equal to about 1.5% of the electrolyte,
and wherein the LiPO2F2 constitutes, by weight, greater than or equal to about 0.5% to less than or equal to about 1.5% of the electrolyte.
Ji discloses a fluorinated electrolyte comprising at least one fluorinated electrolyte additive compound (claim 1). Ji further teaches using lithium difluorophosphate (LiPO2F2) as an additional fluorinated electrolyte additive and further discloses that electrolyte additives may be present in amounts ranging from about 0.2% to less than 10%, by weight, of the electrolyte, which includes values within the claimed range (Ji, specification, [0060]-[0063]).
Therefore, it would have been obvious to someone of ordinary skill in the art before the effective filing date of the claimed invention to include LiPO2F2 in the electrolyte of Zheng in an amount within the range as taught by Ji because Ji teaches that such electrolyte additives are suitable for use in lithium-ion battery electrolytes and provide improved battery performance (Ji, specification, [0055]), and that their use in such amounts as taught by Ji would have yielded predictable results in terms of battery performance.
Regarding claim 11, modified Zheng teaches all features of claim 10 as described above, including a lithium-ion battery and electrolyte comprising a fluorinated phosphate ester additive, a lithium salt, and a mixture of a cyclic carbonate such as EC and a linear carbonate such as DMC. However, modified Zheng does not expressly disclose a battery electrolyte wherein:
the lithium salt comprises both lithium hexafluorophosphate (LiPF6) and lithium difluoro(oxalato)borate (LiDFOB), and
the electrolyte further comprises both fluoroethylene carbonate (FEC) and vinylene carbonate (VC).
Ji discloses a lithium-ion battery electrolyte comprising a lithium salt wherein:
the lithium salt comprises both lithium hexafluorophosphate (LiPF6) and lithium difluoro(oxalato)borate (LiDFOB) (Ji, specification, [0216]), and
the electrolyte further comprises both fluoroethylene carbonate (FEC) and vinylene carbonate (VC) (Ji, specification, [0058]-[0060]).
Therefore, it would have been obvious to someone of ordinary skill in the art before the effective filing date of the claimed invention to further modify the electrolyte of Zheng to (1) include a lithium salt comprising lithium hexafluorophosphate (LiPF6) and lithium difluoro(oxalato)borate (LiDFOB) and (2) to include fluoroethylene carbonate (FEC) and vinylene carbonate (VC), as taught by Ji, because Ji teaches that such salts and organic solvent mixtures are suitable for lithium-ion battery electrolyte systems and provide improved battery performance (Ji, specification, [0055]). The combination of known salt and solvent components in lithium-ion battery electrolytes would have yielded predictable results in terms of battery performance.
Regarding claim 12, modified Zheng teaches all features of claim 11 as described above. However, Zheng does not expressly teach that:
the fluorinated phosphate ester additive constitutes, by weight, greater than or equal to about 1.5% to less than or equal to about 2.5% of the electrolyte,
the LiDFOB constitutes, by weight, greater than or equal to about 0.5% to less than or equal to about 1.5% of the electrolyte,
the FEC constitutes, by weight, greater than or equal to about 1.5% to less than or equal to about 2.5% of the electrolyte,
and the VC constitutes, by weight, greater than or equal to about 0.5% to less than or equal to about 1.5% of the electrolyte.
Ji discloses a fluorinated phosphate ester, lithium difluoro(oxalato)borate (LiDFOB), fluoroethylene carbonate (FEC), and vinylene carbonate (VC) as electrolyte additives for lithium-ion battery electrolytes (Ji, specification, [0058]-[0063]). Ji further discloses that electrolyte additives may be present in amounts ranging from about 0.2% to less than 10%, by weight, of the electrolyte, which includes values within the claimed ranges (Ji, specification, [0060]-[0063]).
Therefore, it would have been obvious to someone of ordinary skill in the art before the effective filing date of the claimed invention to include a fluorinated phosphate ester, LiDFOB, FEC, and VC in the electrolyte of Zheng in an amount within the range as taught by Ji because Ji teaches that such electrolyte additives are suitable for use in lithium-ion battery electrolytes and provide improved battery performance (Ji, specification, [0055]), and that their use in such amounts as taught by Ji would have yielded predictable results in terms of battery performance. Accordingly, when the prior art discloses a general range that overlaps or routinely encompasses the claimed range, a prima facie case of obviousness is established (see MPEP §2144.05).
Claims 15 and 19-20 are rejected under 35 U.S.C. 103 as being unpatentable over Zheng and Kim as applied to claim 13 above, and further in view of Ji (US20200388882A1).
Regarding claim 15, modified Zheng teaches all features of claim 14 as described above, but does not disclose that the fluorinated phosphate ester additive comprises tris(1,1,1,3,3,3-hexafluoropropan-2-yl) phosphate, tris(1,1,1,5,5,5-hexafluoropentan-3-yl) phosphate, tris(1,1,1,2,3,3,3-heptafluoropropan-2-yl) phosphate, or a combination thereof.
Ji teaches a lithium-ion battery comprising a fluorinated electrolyte additive compound comprising tris(1,1,1,3,3,3-hexafluoropropan-2-yl) phosphate (Ji, specification, [0067], [0184]). Ji further teaches that including fluorinated electrolyte additives into electrolyte solutions enhances the thermal stability of the electrolyte and improves the overall electrochemical performance and safety of the battery due to their beneficial flame resistance and fire-retardant properties (Ji, specification, [0042]).
Therefore, it would have been obvious to someone of ordinary skill in the art before the effective filing date of the claimed invention to further modify the electrolyte composition of Zheng to include a fluorinated electrolyte additive compound comprising tris(1,1,1,3,3,3-hexafluoropropan-2-yl) phosphate as taught by Ji, because such additives were known to improve lithium-ion battery performance in terms of flammability and safety. The modification would have involved the use of known electrolyte additives to perform the same function of improving the battery in a predictable manner.
Regarding claim 19, modified Zheng teaches all features of claim 13 as described above, including a lithium-ion battery comprising an electrolyte that comprises a fluorinated phosphate ester additive, a lithium salt, and a mixture of a cyclic carbonate and a linear carbonate. Zheng further teaches that the electroactive material of the positive electrode comprises a layered lithium- and manganese-rich transition metal oxide (Zheng, pg. 292, column 1, paragraph 2). However, Zheng does not expressly teach an electrolyte wherein:
the electrolyte comprises a mixture of both a cyclic carbonate such as fluoroethylene carbonate (FEC) and a linear carbonate such as diethyl carbonate (DEC),
the lithium salt comprises lithium hexafluorophosphate (LiPF6) and further comprises lithium difluorophosphate (LiPO2F2),
and wherein the fluorinated phosphate ester additive constitutes, by weight, greater than or equal to about 0.5% to less than or equal to about 1.5% of the electrolyte,
and the LiPO2F2 constitutes, by weight, greater than or equal to about 0.5% to less than or equal to about 1.5% of the electrolyte.
Ji discloses fluoroethylene carbonate (FEC), diethyl carbonate (DEC), a lithium salt such as lithium hexafluorophosphate (LiPF6), an additional lithium salt such as lithium difluorophosphate (LiPO2F2), and a fluorinated phosphate ester as electrolyte additives for lithium-ion battery electrolytes (Ji, specification, [0056], [0061]-[0063]). Ji further discloses that electrolyte additives may be present in amounts ranging from about 0.2% to less than 10%, by weight, of the electrolyte, which includes values within the claimed ranges (Ji, specification, [0060]-[0063]).
Therefore, it would have been obvious to someone of ordinary skill in the art before the effective filing date of the claimed invention to further modify the electrolyte of Zheng to include a mixture of the cyclic carbonate FEC and the linear carbonate DEC, LiPF6, and LiPO2F2, as taught by Ji, because Ji teaches that such electrolyte additives are suitable for use in lithium-ion battery electrolytes and provide improved battery performance (Ji, specification, [0055]). It would have been further been obvious to use these compounds in an amount within the range taught by Ji for the additives (0.2% to less than 10%, by weight), because when the prior art discloses a general range that overlaps or routinely encompasses the claimed range, a prima facie case of obviousness is established (see MPEP §2144.05).
Regarding claim 20, modified Zheng teaches all features of claim 13 as described above. Zheng further teaches that the electroactive material of the positive electrode comprises a layered lithium nickel-rich transition metal oxide (Zheng, pg. 292, column 1, paragraph 2), and that the electrolyte may include: a cyclic carbonates such as ethylene carbonate (EC), fluoroethylene carbonate (FEC), or a linear carbonate such as dimethyl carbonate (DMC) (Zheng, Figs. 1-2), and a lithium salt (Zheng, LiFSI; pg. 292, column 2, paragraph 2, lines 1-3). However, Zheng does not expressly teach an electrolyte wherein:
the lithium salt comprises both lithium hexafluorophosphate (LiPF6) and lithium difluoro(oxalato)borate (LiDFOB),
the electrolyte further comprises a mixture of both fluoroethylene carbonate (FEC) and vinylene carbonate (VC),
and wherein the fluorinated phosphate ester additive constitutes, by weight, greater than or equal to about 1.5% to less than or equal to about 2.5% of the electrolyte,
the LiDFOB constitutes, by weight, greater than or equal to about 0.5% to less than or equal to about 1.5% of the electrolyte,
the FEC constitutes, by weight, greater than or equal to about 1.5% to less than or equal to about 2.5% of the electrolyte,
and the VC constitutes, by weight, greater than or equal to about 0.5% to less than or equal to about 1.5% of the electrolyte.
Ji discloses a lithium-ion battery and electrolyte comprising lithium salt and lithium carbonate additives, wherein:
the lithium salt comprises both lithium hexafluorophosphate (LiPF6) and lithium difluoro(oxalato)borate (LiDFOB) (Ji, specification, [0216]), and
the electrolyte comprises both fluoroethylene carbonate (FEC) and vinylene carbonate (VC) (Ji, specification, [0058]-[0060]),
Ji further discloses that electrolyte additives may be present in amounts ranging from about 0.2% to less than 10%, by weight, of the electrolyte, which includes values within the claimed ranges (Ji, specification, [0060]-[0063]).
Therefore, it would have been obvious to someone of ordinary skill in the art before the effective filing date of the claimed invention to further modify the electrolyte of Zheng to include a mixture of carbonate additives such as a cyclic carbonate such as ethylene carbonate (EC), fluoroethylene carbonate (FEC), and/or vinylene carbonate (VC) and a linear carbonate such as dimethyl carbonate (DMC), and to also include lithium salts such as LiPF6, and LiDFOB as electrolyte additives, as taught by Ji, because Ji teaches that such electrolyte additives are suitable for use in lithium-ion battery electrolytes and provide improved battery performance (Ji, specification, [0055]). It would have been further been obvious to use these compounds in an amount within the range taught by Ji for the additives (0.2% to less than 10%, by weight), because when the prior art discloses a general range that overlaps or routinely encompasses the claimed range, a prima facie case of obviousness is established (see MPEP §2144.05).
Allowable Subject Matter
Claims 21-22 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
The following are statements of reasons for the indication of allowable subject matter:
Regarding claim 21, the prior art of record, specifically the combination of Zheng, Kim, and Ji as applied to claims 13 and 19, fails to teach, suggest, or render obvious an electrolyte composition that consists of FEC, DEC, LiPF6, LiPO2F2, and the fluorinated phosphate ester additive, as required by dependent claim 21. While the combined teachings of the prior art disclose the individual components of the claimed electrolyte within various broader mixtures, the prior art does not teach or suggest an electrolyte restricted solely to these specific five components to the exclusion of all other electrolyte solvents, additives, or salts. Furthermore, there is no motivation or suggestion in the prior art that would lead a person of ordinary skill in the art to selectively substitute, remove, or isolate only these specific components to arrive at the closed-ended, "consisting of" mixture of claim 21. The specific combination and restriction of these components yields an allowable, non-obvious electrolyte composition.
Regarding claim 22, the prior art of record, specifically the combination of Zheng, Kim, and Ji as applied to claims 13 and 20, fails to teach, suggest, or render obvious an electrolyte composition that consists of EC, DMC, LiPF6, LiDFOB, FEC, VC, and the fluorinated phosphate ester additive, as required by dependent claim 22. While the combined teachings of the prior art disclose the individual components of the claimed electrolyte within various broader mixtures, the prior art does not teach or suggest an electrolyte restricted solely to these specific seven components to the exclusion of all other electrolyte solvents, additives, or salts. Furthermore, there is no motivation or suggestion in the prior art that would lead a person of ordinary skill in the art to selectively substitute, remove, or isolate only these specific components to arrive at the closed-ended, "consisting of" mixture of claim 22. The specific combination and restriction of these components yields an allowable, non-obvious electrolyte composition.
Response to Arguments
Response -— Claim Rejections 35 USC § 102 and 103
Regarding independent claims 1 and 13, Applicant's arguments filed on June 25th, 2026 have been fully considered but they are not found persuasive.
On page 10 of the response, Applicant states that the electrolyte described in Zheng does not include "a cyclic carbonate," nor does it include "0.5% to 2.5%, by weight, of a fluorinated phosphate ester additive," as recited in claims 1 and 13. Applicant further states that the electrolyte described in Zheng does not include "greater than 70%, by weight, of a mixture of a cyclic carbonate and a linear carbonate" and "0.5% to 2.5%, by weight, of a fluorinated phosphate ester additive," as recited in amended claims 1 and 13.
In response, the Examiner notes that the Applicant’s arguments regarding this limitation in claims 1 and 13 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.
Regarding claims 10 and 13, Applicant's arguments filed on June 25th, 2026 have been fully considered but they are not found persuasive.
On page 11 of the response, Applicant states that Zheng does not describe an electrolyte comprising a cyclic carbonate, a linear carbonate, and a fluorinated phosphate ester additive, as required in claim 13. Nor does Zheng describe an electrolyte comprising EC, DMC, and a fluorinated phosphate ester additive, as required in claim 10.
In response, the Examiner notes that the Applicant’s arguments regarding this limitation in claims 10 and 13 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.
Regarding claims 15 and 18-20, Applicant's arguments filed on June 25th, 2026 have been fully considered but they are not found persuasive.
On page 12 of the response, Applicant states that Zheng fails to describe an electrolyte comprising "greater than 70%, by weight, of a mixture of a cyclic carbonate and a linear carbonate" and "0.5% to 2.5%, by weight, of a fluorinated phosphate ester additive," as recited in claims 1 and 13.
In response, the Examiner notes that the Applicant’s arguments regarding this limitation in claims 1 and 13 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 page 12 of the response, Applicant states that Ji lists hundreds of examples of fluorine-containing additives but never indicates that any of the hundreds of fluorine-containing additives listed therein may be included in an electrolyte comprising LiFSI and FEMC, such as the LiFSI/TFEP/FEMC electrolyte of Zheng. Therefore, an ordinarily skilled artisan would not have had a reasonable expectation of success in modifying the LiFSI/TFEP/FEMC electrolyte of Zheng to include any of the fluorine-containing additives listed in Ji in any amount.
The Examiner respectfully disagrees. A reference does not fail to provide a reasonable expectation of success merely because it discloses a plurality of options. Ji explicitly states that an electrolyte additive may be a Li salt compound, listing options such as LiPF6 and LiFSI, and further states that the electrolyte may include one or more additives (Ji, specification, [0060], [0063]). Regarding the fluorine-containing additives, Ji explicitly teaches a list of fluorinated phosphate additives, and states that such additives in the electrolyte are useful for improving battery performance and safety due to their versatility in reaction chemistry and excellent flame resistant and flame retardant properties (Ji, specification, [0041]-[0042]). One of ordinary skill in the art seeking to improve or optimize the thermal safety profile of the electrolyte system disclosed in Zheng/Kim would be motivated to select a fluorinated phosphate additive from the designated list provided in Ji, as Ji explicitly provides a finite number of predictable choices to achieve that exact result. The reasonable expectation of success need not be absolute certainty, but rather a reasonable expectation that the features will perform their known functions. Therefore, since Ji explicitly discloses the list of fluorinated additives within a finite, disclosed group of functional alternatives for lithium battery electrolytes, and further lists LiPF6 and LiFSI as Li salt additives that can be included in the electrolyte, a person of ordinary skill in the art would have had a reasonable expectation of success in incorporating Ji's additives into Zheng/Kim's electrolyte.
On page 12 of the response, Applicant further states that Ji never indicates that any of the hundreds of fluorine-containing additives listed therein may be included in an electrolyte comprising a cyclic carbonate and a linear carbonate, as required in claims 1 and 13 because no single embodiment of Ji describes an electrolyte comprising a cyclic carbonate, a linear carbonate, and a fluorine-containing additive. Further, none of the example electrolytes described in Ji include a fluorine-containing additive at all.
The Examiner respectfully disagrees. It is well-established that a prior art reference is not limited to its specific working examples or preferred embodiments but must be read for all that it teaches to one of ordinary skill in the art (In re Lamberti, 545 F.2d 747, 750 (CCPA 1976)). Zheng/Kim establish the base cyclic/linear carbonate solvent system; Ji provides and explicitly discloses that the electrolyte composition can further comprise a fluorinated phosphate additive and explicitly provides a finite list of additives suitable for use (Ji, specification, [0067], [0184]). Ji further teaches the electrolyte may further comprise a mixture of additives such as a cyclic carbonate such as ethylene carbonate (EC), fluoroethylene carbonate (FEC), and/or vinylene carbonate (VC) and a linear carbonate such as dimethyl carbonate (DMC) (Ji, specification, [0058]-[0060]). The fact that Ji discloses a list of alternatives does not render the selection of one such alternative non-obvious, especially where the reference provides an explicit functional reason (i.e. improved thermal safety; Ji, specification, [0041]-[0042]) to make the selection.
On page 12 of the response, Applicant further states that Ji does not provide any indication as to which of the hundreds of possible combinations of solvents and fluorine-containing additives is likely to be successful and does not recognize the amount of the fluorine-containing additive in the electrolyte as a result effective variable.
The Examiner respectfully disagrees. It is well-established that a prior art reference is not limited to its specific working examples or preferred embodiments but must be read for all that it teaches to one of ordinary skill in the art (In re Lamberti, 545 F.2d 747, 750 (CCPA 1976)). As discussed above, Zheng/Kim established the base cyclic/linear carbonate solvent system. Ji provides a discrete list of fluorinated phosphate additives and carbonate additives known to improve safety. Combining a known safety additive with a known solvent system yields a predictable result (a safer electrolyte). The choice of an additive from Ji’s disclosed list is an "obvious to try" scenario of predictable options.
Regarding the argument that Ji does not recognize the amount of the fluorine-containing additive as a result-effective variable, the Examiner notes that the current rejections of the claims that utilize Ji as a secondary reference (claims 3, 8-9, 11-12, 15, and 19-20) do not rely on a 'result-effective variable' theory, nor was this doctrine invoked in the previous Office Action. Rather, the rejections are based on the explicit teachings of Ji, which are that the amount of the claimed additives, including the Li salts, fluorinated phosphate additives, and carbonate additives, may be present in amounts ranging from about 0.2% to less than 10%, by weight, of the electrolyte, which includes values within the claimed range (Ji, specification, [0060]-[0063]). Therefore, Applicant's argument is misdirected and unpersuasive.
On page 13 of the response, Applicant further states that an ordinarily skilled artisan would have been dissuaded from modifying and/or combining the disclosures of Zheng and Ji to arrive at the electrolyte recited in claims 1 and 13 at least because Zheng teaches away from the use of organic carbonate solvents and/or LiPF6 in electrolytes of Li-ion batteries.
In response, the Examiner notes that the Applicant’s arguments regarding this limitation in claims 1 and 13 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.
However, regarding the argument that Zheng teaches away from the use of organic carbonate solvents and/or LiPF6 in electrolytes of Li-ion batteries, the Examiner respectfully disagrees. A reference does not teach away simply by disclosing disadvantages, limitations, or a preferred embodiment, provided it does not criticize, discredit, or discourage the claimed solution to the extent that a person of ordinary skill in the art would be led away from it (see MPEP 2145). Contrary to Applicant's assertion, Zheng explicitly acknowledges that LiPF₆ is commonly employed in state-of-the-art Li-ion electrolytes due to its critical ability to provide good passivation of an aluminum cathode current collector (Zheng, pg. 291, col. 2, para. 2). While Zheng notes the thermal and chemical instability of LiPF₆ at elevated temperatures or over time, this disclosure merely represents a statement of known trade-offs standard within the battery art, rather than a statement that LiPF₆ is inoperative or should never be used. The fact that Zheng explores alternative imide-based salts (like LiFSI) to improve upon specific performance metrics does not negate the viability or standard nature of LiPF₆ or organic carbonates in Li-ion systems. Since Zheng confirms that LiPF₆ is standard in the art, a person of ordinary skill in the art at the time of the invention would have been motivated to utilize or evaluate such standard electrolyte components, balancing their known benefits (such as suitable passivation) against their drawbacks. Lastly, it is worth noting that the Li salt identity is not recited in independent claims 1 or 13, meaning that LiPF6 is not a requirement for those claims.
On page 13 of the response, Applicant further states that modifying the electrolyte of Zheng to include the organic carbonates and/or the LiPF₆ of Ji would necessarily undermine the stated purpose of the LiFSI/TFEP/FEMC electrolyte of Zheng (to eliminate the use of organic carbonate solvents and/or LiPF6 in electrolytes of Li-ion batteries).
The Examiner respectfully disagrees. A proposed modification renders a reference unsatisfactory for its intended purpose only if the modified structure becomes inoperable or fails to perform its foundational function. In this case, the addition of organic linear/cyclic carbonates and/or LiPF₆ additives as taught by Ji does not render Zheng/Kim’s electrolyte inoperable; the resulting electrolyte mixture would still function as a viable ionic conductor within a lithium-ion battery. Furthermore, a prior art’s statement of preference or focus on a specific problem (e.g., eliminating the use of organic carbonates) does not constitute a "teaching away" from alternative configurations under MPEP § 2143.01(I). A PHOSITA would be motivated to introduce the additives such as the organic carbonates and/or LiPF₆ of Ji into the electrolyte of Zheng/Kim, to take advantage of the predictable properties taught by Ji, namely improved thermal and flammability safety and improved electrochemical performance (Ji, specification, [0041]-[0042]), while simultaneously minimizing organic carbonates. Therefore, the combination would yield a predictable electrolyte composition that achieves the desired thermal safety metrics without hindering basic battery operations.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure:
Masahiro (JP2013157280A): appears to disclose a lithium-ion battery and electrolyte comprising fluorine-containing phosphate additives (Masahiro, claims).
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.
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/A.R.O./Examiner, Art Unit 1789
/MARLA D MCCONNELL/Supervisory Patent Examiner, Art Unit 1789
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