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 .
Information Disclosure Statement
The information disclosure statement (IDS) submitted on 5/20/24 was filed. The submission is in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement has been considered by the examiner.
Drawings
The drawings were received on 7/24/23. These drawings are acceptable.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
Claims 1-2 and 4-20 are rejected under 35 U.S.C. §103 as being unpatentable over WO 2022/072839 A1 (“WO’839”) in view of Synthesis of Flame-Retardant Phosphaphenanthrene Derivatives, Australian Journal of Chemistry, 2014 (“Zheng”).
As to Claim 1:
WO’839 discloses:
an electrolyte comprising an aprotic organic solvent and a metal salt. Specifically, WO’839 discloses an electrolyte including an aprotic organic solvent system selected from open-chain or cyclic carbonates, ethers, sulfones, lactones, and glymes ([0008], [0010], [0023]–[0024]);
the electrolyte comprises a metal salt, including alkali-metal salts such as lithium salts (e.g., LiPF₆, LiTFSI, LiFSI), dissolved in the aprotic organic solvent ([0010], [0022]); and
the inclusion of a phosphorus-containing additive in the electrolyte to improve safety and thermal stability of the electrolyte ([0006], [0019]).
However, WO’839 does not disclose that the phosphorus-containing additive is a DOPO-based phosphaphenanthrene-oxide compound according to Formula I, as recited in Claim 1. The additives disclosed in WO’839 are silyl-thiophosphate or phosphate derivatives and do not include a phosphaphenanthrene (DOPO) core.
Zheng discloses the synthesis of DOPO-based phosphaphenanthrene-oxide derivatives and teaches their use as flame-retardant additives. The reference expressly describes multiple phosphaphenanthrene-oxide (DOPO) derivatives and reports their incorporation into conventional lithium-ion battery electrolytes to impart flame-retardant and thermal-stability properties (Abstract; pp. 1688–1690; Schemes 1–2). Thus, Zheng teaches the DOPO-based compounds missing from WO’839 and demonstrates their suitability for use in electrolyte compositions.
WO’839 and Zheng are analogous arts because both are directed to lithium-ion battery electrolyte safety and stability and both address the use of phosphorus-containing additives to improve flame retardancy and thermal performance of electrolytes.
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to modify the electrolyte of WO’839 by substituting or supplementing the phosphorus-containing additives disclosed therein with the DOPO-based phosphaphenanthrene-oxide compounds taught by Zheng in order to achieve predictable improvements in flame retardancy and thermal stability, thereby arriving at the electrolyte comprising an aprotic organic solvent, a metal salt, and a DOPO-based compound as recited in Claim 1.
As to Claim 2:
Specifically, WO’839 discloses an electrolyte including an aprotic organic solvent system selected from open-chain or cyclic carbonates, ethers, sulfones, lactones, and glymes ([0008], [0010], [0023]–[0024]). WO’839 further discloses that the electrolyte comprises a metal salt, including alkali-metal salts such as lithium salts (e.g., LiPF₆, LiTFSI, LiFSI), dissolved in the aprotic organic solvent ([0010], [0022]). WO’839 also teaches the inclusion of a phosphorus-containing additive in the electrolyte to improve safety and thermal stability ([0006], [0019]).
However, WO’839 does not disclose that the phosphorus-containing additive is one of the specific DOPO-based phosphaphenanthrene-oxide structures recited in Claim 2. The additives disclosed in WO’839 are silyl-thiophosphate or phosphate derivatives and do not include the particular phosphaphenanthrene-oxide structures illustrated in Claim 2.
Zheng discloses the synthesis of specific DOPO-based phosphaphenanthrene-oxide derivatives, including multiple explicitly illustrated structures derived from phosphaphenanthrene (DOPO) cores (Abstract; Schemes 1–2; pp. 1689–1692). The reference further reports that these specific DOPO-based compounds are incorporated into conventional lithium-ion battery electrolytes and function as flame-retardant additives while maintaining electrolyte performance (pp. 1688–1690). Thus, Zheng teaches the particular DOPO-based structures required by Claim 2 that are not disclosed in WO’839.
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to modify the electrolyte of WO’839 by substituting or supplementing the phosphorus-containing additives disclosed therein with one or more of the specific DOPO-based phosphaphenanthrene-oxide compounds taught by Zheng in order to obtain predictable improvements in flame retardancy and thermal stability, thereby arriving at the electrolyte comprising the specific DOPO-based structures as recited in Claim 2.
As to Claim 4:
WO’839 discloses an electrolyte as recited in claim 3, comprising an aprotic organic solvent, a metal salt, and a phosphorus-containing additive present in an ionic environment. Specifically, WO’839 discloses electrolyte compositions including ionic species and salts having phosphate and imide anions, such as lithium phosphate-based and imide-based salts ([0010], [0022]). WO’839 further teaches that such anions are suitable for use in lithium-ion battery electrolytes to provide electrochemical stability and safety benefits ([0006], [0019]).
However, WO’839 does not expressly disclose that the anion associated with the compound according to Formula I is selected from the full list of anions recited in Claim 4, including halide, nitrate, borate, carbonate, sulfate, acetate, formate, hydroxide, and the other enumerated species.
Zheng discloses DOPO-based phosphaphenanthrene derivatives used as flame-retardant additives in lithium-ion battery electrolytes and teaches that such phosphorus-containing compounds are compatible with phosphate-type anionic structures commonly used in electrolyte formulations (Abstract; pp. 1688–1690; Schemes 1–2). Thus, Zheng reinforces the use of phosphate anions, which are expressly recited in Claim 4, in combination with phosphaphenanthrene-based compounds in battery electrolytes.
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to modify the electrolyte of WO’839 by selecting an anion for the compound according to Formula I from among known electrolyte-compatible anions, such as phosphate or imide anions, as taught or suggested by Zheng, thereby arriving at an electrolyte wherein the anion is one of the species recited in Claim 4.
As to Claim 5:
WO’839 discloses an electrolyte as recited in claim 1, comprising an aprotic organic solvent, a metal salt, and a phosphorus-containing additive. Specifically, WO’839 teaches electrolyte compositions in which additives are incorporated in minor amounts relative to the solvent, consistent with conventional electrolyte formulations ([0019], [0021]). WO’839 further teaches that such additives are included in amounts effective to impart safety and thermal-stability benefits without materially impairing electrolyte performance ([0006], [0019]).
However, WO’839 does not expressly disclose that the compound according to Formula I is present in a concentration of from 0.01 wt.% to 10 wt.% in the electrolyte, as specifically recited in Claim 5.
Zheng discloses DOPO-based phosphaphenanthrene derivatives used as flame-retardant additives in lithium-ion battery electrolytes and reports that such additives are incorporated at low weight-percent levels in conventional electrolyte formulations (Abstract; pp. 1689–1690). The concentrations disclosed in Zheng overlap the claimed range of 0.01 wt.% to 10 wt.%, thereby teaching the specific additive concentration missing from WO’839.
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to modify the electrolyte of WO’839 by selecting an additive concentration for the compound according to Formula I within the range of 0.01 wt.% to 10 wt.%, as taught by Zheng, in order to achieve predictable flame-retardant and safety benefits while maintaining electrolyte performance, thereby arriving at the composition recited in Claim 5.
As to Claim 6:
WO’839 discloses an electrolyte composition comprising an aprotic organic solvent, wherein the aprotic organic solvent includes open-chain or cyclic carbonates, carboxylic acid esters, nitrite, ethers, sulfones, ketones, lactones, dioxolanes, glymes, crown ethers, siloxanes, phosphoric acid esters, phosphites, mono- or polyphosphazenes, or mixtures thereof ([0023]).
As to Claim 7:
WO’839 discloses an electrolyte as recited in claim 1, comprising an aprotic organic solvent and a metal salt. Specifically, WO’839 teaches electrolyte formulations in which the aprotic organic solvent constitutes the major component of the electrolyte, with lithium salt and additives present in lesser amounts ([0019], [0021], [0023]). WO’839 further teaches that such solvent-rich formulations are conventional and suitable for lithium-ion battery operation ([0010], [0022]).
However, WO’839 does not expressly disclose that the aprotic organic solvent is present in a concentration of from 60 wt.% to 90 wt.% in the electrolyte, as specifically recited in Claim 7.
Zheng discloses the use of DOPO-based phosphaphenanthrene derivatives as flame-retardant additives in conventional lithium-ion battery electrolyte formulations, wherein the electrolyte is predominantly composed of aprotic organic solvent and the additives are present at low weight percentages (Abstract; pp. 1689–1690). Such conventional electrolyte formulations necessarily employ solvent contents that overlap the claimed range of 60 wt.% to 90 wt.%, thereby teaching the solvent concentration missing from WO’839.
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to formulate the electrolyte of WO’839 such that the aprotic organic solvent is present in a concentration of from 60 wt.% to 90 wt.%, as taught by conventional lithium-ion electrolyte formulations exemplified by Zheng, in order to achieve predictable electrolyte performance and compatibility with phosphaphenanthrene-based additives, thereby arriving at the composition recited in Claim 7.
As to Claim 8:
WO’839 discloses an electrolyte composition as recited in claim 1, comprising an aprotic organic solvent, a metal salt, and an additive compound. WO’839 teaches that the electrolyte is suitable for lithium-ion batteries and explicitly discloses the use of alkali-metal salts, including lithium salts, as the conductive salt in the electrolyte ([0010], [0018], [0021]). Thus, WO’839 teaches a composition in which the cation of the metal salt may be lithium, as commonly employed in lithium-ion battery electrolytes.
However, WO’839 does not explicitly limit the electrolyte composition to one in which the cation of the metal salt is lithium, as specifically recited in Claim 8.
Zheng discloses electrolyte systems used in lithium-ion batteries, wherein lithium salts are employed as the metal salt to provide lithium cations for electrochemical operation (Abstract; pp. 1688–1689). This reference thus teaches the use of lithium as the metal-salt cation in electrolyte formulations incorporating phosphorus-containing additives.
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to select lithium as the cation of the metal salt in the electrolyte composition of WO’839, as taught by conventional lithium-ion battery electrolyte formulations exemplified by Zheng, in order to achieve predictable electrochemical performance, thereby arriving at the composition recited in Claim 8.
As to Claim 9:
WO’839 discloses an electrolyte composition according to claim 1, comprising an aprotic organic solvent, a metal salt, and a phosphorus-containing additive compound suitable for use in lithium-ion batteries ([0008]–[0010]). WO’839 further teaches that the electrolyte includes a metal salt dissolved in the solvent to provide ionic conductivity and describes conventional electrolyte formulations used in rechargeable batteries ([0018], [0021]). Thus, WO’839 teaches the presence of a metal salt in the electrolyte composition.
However, WO’839 does not expressly disclose that the metal salt is present in a concentration of from 10 wt.% to 30 wt.%, as specifically recited in Claim 9.
Zheng teaches electrolyte formulations for lithium-ion batteries employing lithium salts in conventional concentration ranges sufficient to achieve ionic conductivity, typically corresponding to high-salt loadings within routine electrolyte design parameters (Abstract; pp. 1688–1690). The reference demonstrates that adjusting the concentration of lithium salt within such ranges is a matter of routine optimization to balance conductivity, viscosity, and electrochemical stability.
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to adjust the concentration of the metal salt in the electrolyte composition of WO’839 to a value within the range of 10 wt.% to 30 wt.%, as taught by conventional lithium-ion battery electrolyte formulations exemplified by Zheng, in order to achieve predictable ionic conductivity and battery performance, thereby arriving at the composition recited in Claim 9.
As to Claim 10:
WO’839 discloses an electrolyte composition comprising an aprotic organic solvent, a metal salt, and a phosphorus-containing compound suitable for use in lithium-ion batteries ([0008]–[0011]). WO’839 further teaches that the disclosed phosphorus-containing compounds function to improve thermal stability, flame retardancy, and electrochemical performance when incorporated into battery electrolytes ([0012], [0024]). Such phosphorus-containing compounds are conventionally understood in the art to function as electrolyte additives when present in addition to the solvent and lithium salt. Thus, WO’839 teaches an electrolyte composition that includes at least one additive.
However, WO’839 does not explicitly recite the electrolyte composition as “further comprising at least one additive” using that exact terminology, nor does it expressly distinguish the phosphorus-containing compound as an additive separate from the base electrolyte components.
Zheng explicitly teaches the use of phosphorus-containing compounds as flame-retardant additives in electrolyte systems for lithium-ion batteries, where such compounds are added in addition to the base solvent and lithium salt to enhance safety and thermal stability (Abstract; pp. 1688–1691). The reference clearly characterizes these compounds as additives introduced into conventional electrolyte formulations.
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to formulate the electrolyte composition of WO’839 so as to further comprise at least one additive, as explicitly taught by Zheng, because the use of phosphorus-containing compounds as electrolyte additives was well known and predictably improves flame retardancy and thermal stability, thereby arriving at the composition recited in Claim 10.
As to Claim 11:
WO’839 discloses an electrolyte composition further comprising at least one additive ( [0026]–[0029]). WO’839 explicitly teaches that, in some embodiments, the additive comprises one or more selected from a sulfur-containing compound, phosphorus-containing compound, boron-containing compound, silicon-containing compound, fluorine-containing compound, nitrogen-containing compound, a compound containing at least one unsaturated carbon-carbon bond, a carboxylic acid anhydride, an epoxide, or mixtures thereof ([0028]).
As to Claim 12:
WO’839 discloses an electrolyte composition comprising an aprotic organic solvent, a lithium salt, and at least one additive in the form of a phosphorus-containing compound used to improve flame retardancy and thermal stability of lithium-ion battery electrolytes ([0008]–[0012], [0024]). WO’839 further teaches that such additives are incorporated into electrolyte compositions in minor amounts relative to the solvent, consistent with conventional electrolyte formulation practices ([0026], [0031]). Thus, WO’839 teaches an electrolyte composition comprising at least one additive, as required by Claim 12.
However, WO’839 does not expressly disclose that the at least one additive is present in a concentration of from 0.01 wt.% to 10 wt.%, as specifically recited in Claim 12.
Zheng teaches that phosphorus-containing flame-retardant additives for lithium-ion battery electrolytes are typically incorporated at low weight percentages, including concentrations within the range of about 0.1 wt.% to several weight percent, in order to balance flame retardancy, ionic conductivity, and electrochemical stability (Abstract; pp. 1689–1692). These disclosed concentration ranges fall within, and overlap with, the claimed range of 0.01 wt.% to 10 wt.% recited in Claim 12.
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to select an additive concentration within the range of 0.01 wt.% to 10 wt.% for the electrolyte composition of WO’839, as taught by Zheng, because optimizing the amount of a known electrolyte additive to achieve a desired balance of flame retardancy and electrochemical performance represents a routine optimization of a result-effective variable, thereby arriving at the composition recited in Claim 12.
As to Claim 13:
WO’839 discloses an electrochemical energy storage device comprising a cathode, an anode, an electrolyte, and a separator. In particular, WO’839 teaches lithium-ion battery cells including a positive electrode (cathode), a negative electrode (anode), and a separator interposed therebetween, the electrodes being impregnated with an electrolyte composition comprising an aprotic organic solvent and a lithium salt ([0002], [0015], [0020]–[0023]). WO’839 further discloses that the electrolyte may include phosphorus-containing compounds as functional components for improving safety and thermal stability ([0024]–[0026]). Thus, WO’839 teaches an electrochemical energy storage device comprising a cathode, an anode, an electrolyte, and a separator, as recited in Claim 13.
However, WO’839 does not expressly disclose that the electrolyte used in the electrochemical energy storage device is the specific electrolyte according to claim 1, including the particular compound according to Formula I as part of the electrolyte composition.
Zheng teaches phosphorus-containing flame-retardant compounds suitable for use as electrolyte components or additives in lithium-ion battery systems, and further teaches incorporating such compounds into electrolyte formulations used in electrochemical energy storage devices to enhance flame retardancy and thermal stability (Abstract; pp. 1689–1692). The reference thus teaches the suitability of the claimed class of phosphorus-containing compounds for use in electrolytes employed in lithium-ion battery devices.
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to employ the electrolyte according to claim 1, including the phosphorus-containing compound taught by Zheng, in the electrochemical energy storage device of WO’839, because the substitution or incorporation of a known electrolyte composition into a known lithium-ion battery device represents a predictable use of prior art elements according to their established functions, thereby arriving at the electrochemical energy storage device recited in Claim 13.
As to Claim 14:
WO’839 discloses an electrochemical energy storage device comprising a cathode, an anode, an electrolyte, and a separator corresponding to the device of claim 13 ([0002], [0015], [0020]–[0023]). WO’839 further teaches that the cathode may be selected from conventional lithium-ion battery cathode active materials, including lithium transition-metal oxides and lithium iron phosphate-type materials, such as layered oxide cathodes and phosphate-based cathodes commonly used in rechargeable lithium-ion batteries ([0018]–[0021]). Thus, WO’839 teaches an electrochemical energy storage device having a cathode of the general type recited in Claim 14.
However, WO’839 does not explicitly enumerate each specific cathode composition recited in Claim 14, such as LiFePO₄, LiCoO₂, LiNiO₂, LiNiₓCoᵧMetᶻO₂, LiMn₂O₄, or AₙB₂(XO₄)₃, nor does it expressly disclose the full range of stoichiometric parameters recited therein.
Zheng teaches the application of phosphorus-containing flame-retardant compounds in lithium-ion battery systems employing conventional cathode chemistries, including layered oxide cathodes and phosphate-based cathodes, such as LiFePO₄, which are standard in the art (Abstract; pp. 1689–1692). The reference confirms that the claimed electrolyte components are compatible with, and intended for use in, lithium-ion batteries employing the types of cathode materials recited in Claim 14.
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to employ any of the well-known lithium-ion battery cathode materials recited in Claim 14, such as LiFePO₄, LiCoO₂, LiNiO₂, or related mixed-metal oxides, in the electrochemical energy storage device of WO’839 in view of Zheng, because the selection of a particular known cathode chemistry from among conventional lithium-ion cathodes represents a routine design choice involving predictable results, thereby arriving at the device recited in Claim 14.
As to Claim 15:
WO’839 discloses an electrochemical energy storage device comprising a cathode, an anode, an electrolyte, and a separator, corresponding to the device of claim 13 ([0002], [0015], [0020]–[0023]). WO’839 further teaches that the anode may be formed from conventional lithium-ion battery anode materials, including carbon-based negative electrodes and lithium-based active materials commonly employed in rechargeable lithium-ion batteries ([0016]–[0019]). Thus, WO’839 teaches an electrochemical energy storage device having an anode of the general type recited in Claim 15.
However, WO’839 does not explicitly enumerate each specific anode material recited in Claim 15, such as lithium metal, graphitic material, amorphous carbon, Li₄Ti₅O₁₂, tin alloy, silicon, silicon alloy, or intermetallic compounds, nor does it expressly list mixtures thereof.
Zheng teaches the use of phosphorus-containing flame-retardant compounds in lithium-ion battery systems employing conventional anode materials, including carbon-based anodes and lithium-containing negative electrodes, and indicates that such electrolyte systems are compatible with a wide range of standard anode chemistries used in the art (Abstract; pp. 1689–1692). This reference confirms that the electrolyte compositions disclosed therein are suitable for use with the types of anode materials recited in Claim 15.
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to employ any of the well-known lithium-ion battery anode materials recited in Claim 15, such as graphitic material, amorphous carbon, lithium metal, Li₄Ti₅O₁₂, silicon-based materials, or mixtures thereof, in the electrochemical energy storage device of WO’839 in view of Zheng, because the selection of a particular known anode material from among conventional lithium-ion anodes represents a routine design choice yielding predictable results, thereby arriving at the device recited in Claim 15.
As to Claim 16:
WO’839 discloses an electrochemical energy storage device comprising a cathode, an anode, an electrolyte, and a separator, corresponding to the device of claim 13 ([0002], [0015], [0020]–[0023]). WO’839 further teaches that the separator is a microporous polymer separator suitable for use in lithium-ion batteries and positioned between the cathode and anode to prevent electrical shorting while permitting ionic transport ([0021]–[0023]). Thus, WO’839 teaches a separator of the general type recited in Claim 16.
However, WO’839 does not explicitly disclose that the separator comprises an electron beam-treated microporous polyolefin separator, nor does it expressly list each of the specific polymer materials recited in Claim 16, such as nylon, cellulose, nitrocellulose, polysulfone, polyacrylonitrile, polyvinylidene fluoride, polypropylene, polyethylene, polybutene, or copolymers or blends thereof.
Zheng teaches that lithium-ion battery systems employing phosphorus-containing flame-retardant electrolyte additives are compatible with conventional microporous polymer separators, including polyolefin- and fluoropolymer-based separators commonly used in commercial lithium-ion batteries (Abstract; pp. 1689–1692). This reference confirms that the electrolyte systems disclosed therein are intended for use with standard separator materials such as polypropylene, polyethylene, and polyvinylidene fluoride, which fall within the scope of Claim 16.
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to employ a known microporous polymer separator, including an electron beam-treated microporous polyolefin separator or a microporous polymer film comprising polypropylene, polyethylene, polyvinylidene fluoride, or blends thereof, in the electrochemical energy storage device of WO’839 in view of Zheng, because the selection of a particular known separator material from among conventional lithium-ion battery separators represents a routine design choice yielding predictable results, thereby arriving at the device recited in Claim 16.
As to Claim 17:
WO’839 discloses an electrochemical energy storage device comprising an electrolyte in which the aprotic organic solvent includes open-chain or cyclic carbonates, carboxylic acid esters, nitrite, ethers, sulfones, ketones, lactones, dioxolanes, glymes, crown ethers, siloxanes, phosphoric acid esters, phosphites, mono- or polyphosphazenes, or mixtures thereof ( [0023]).
As to Claim 18:
WO’839 discloses an electrochemical energy storage device comprising a cathode, an anode, an electrolyte, and a separator, corresponding to the device of claim 13 ([0002], [0015], [0020]–[0023]). WO’839 further discloses that the electrolyte includes a metal salt suitable for lithium-ion batteries, such as lithium-based salts conventionally used in non-aqueous electrolyte systems to enable lithium-ion transport between the electrodes ([0016]–[0019]). Thus, WO’839 teaches a device including an electrolyte containing a metal salt used in lithium-ion electrochemical energy storage devices.
However, WO’839 does not expressly state that the cation of the metal salt is lithium, as specifically recited in Claim 18.
Zheng teaches electrolyte compositions for lithium-ion batteries in which lithium salts are dissolved in aprotic organic solvents together with flame-retardant phosphorus-containing additives (Abstract; pp. 1689–1693). This reference explicitly relies on lithium as the charge-carrying cation in the electrolyte, thereby teaching that lithium is the cation of the metal salt in lithium-ion battery electrolyte systems.
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to employ a lithium cation as the cation of the metal salt in the electrochemical energy storage device of WO’839 in view of Zheng, because lithium salts are standard and well-established charge carriers in lithium-ion battery electrolytes, and their selection represents a routine and predictable design choice, thereby arriving at the device recited in Claim 18.
As to Claim 19:
WO’839 discloses an electrochemical energy storage device comprising a cathode, an anode, an electrolyte, and a separator, corresponding to the device of claim 13 ([0002], [0015], [0020]–[0023]). WO’839 further discloses that the electrolyte includes functional compounds designed to improve safety and electrochemical performance, including phosphorus-containing compounds incorporated into the electrolyte formulation ([0007]–[0012], [0018]). Such compounds function as electrolyte additives to impart flame-retardant and stability-enhancing properties to the electrolyte system. Thus, WO’839 teaches an electrochemical energy storage device in which the electrolyte comprises additional functional components beyond the base solvent and metal salt.
However, WO’839 does not expressly state that the electrolyte further comprises at least one additive, as recited in Claim 19, using the explicit terminology of an “additive” separate from the base electrolyte components.
Zheng teaches electrolyte systems for lithium-ion batteries in which additives—including phosphorus-containing flame-retardant compounds—are intentionally added to conventional electrolytes to improve safety, thermal stability, and electrochemical performance (Abstract; pp. 1689–1694). This reference explicitly characterizes such compounds as electrolyte additives used in addition to the base electrolyte components.
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to modify the electrochemical energy storage device of WO’839 such that the electrolyte further comprises at least one additive, as taught by Zheng, because the use of electrolyte additives—particularly phosphorus-containing additives—for improving safety and stability in lithium-ion batteries was well known and represents a routine and predictable design choice, thereby arriving at the device recited in Claim 19.
As to Claim 20:
WO’839 discloses an electrochemical energy storage device comprising an electrolyte that may further include at least one additive ( [0026]–[0029]). WO’839 explicitly teaches that the additive may be a sulfur-containing compound, phosphorus-containing compound, boron-containing compound, silicon-containing compound, fluorine-containing compound, nitrogen-containing compound, a compound containing at least one unsaturated carbon-carbon bond, a carboxylic acid anhydride, an epoxide, or mixtures thereof ([0028]).
Claim 3 is rejected under 35 U.S.C. § 103 as being unpatentable over WO 2022/072839 A1 (“WO’839”) in view of Synthesis of flame-retardant phosphaphenanthrene derivatives, Australian Journal of Chemistry (2014) (“Zheng”), as applied to Claim 1 above, and further in view of US 2021/0036369 A1 (“US’369”).
As to Claim 3:
WO’839 discloses an electrolyte composition for electrochemical energy storage devices comprising phosphorus-containing compounds defined by a structural formula (Formula I or an equivalent generic structure) suitable for use in battery electrolytes ( [0030]–[0036], [0041]–[0044]; Figs. 1–3).WO’839 further teaches that the disclosed compounds may be present as ionic species or salts suitable for electrolyte environments, thereby satisfying the recitation of an electrolyte comprising a compound according to Formula I ( [0046]–[0049]).
However, WO’839 does not expressly disclose that R is an organic cation ionically bonded to an anion, nor does WO’839 explicitly identify the organic cation as imidazolium, pyrrolidinium, piperidinium, or ammonium, as specifically recited in Claim 3.
Zheng discloses phosphaphenanthrene-based ionic compounds in which the phosphorus-containing core structure is ionically bonded to organic cations, including imidazolium and ammonium cations, for use as flame-retardant and functional ionic materials (pp. 1208–1211; Scheme 1; Table 1). This teaching satisfies the limitation that R is an organic cation ionically bonded to an anion, and further teaches at least one of the specific organic cations recited in Claim 3.
US’369 further teaches electrolyte salts and ionic liquids for electrochemical devices comprising organic cations ionically bonded to anions, explicitly including imidazolium, pyrrolidinium, and ammonium cations, selected for electrolyte stability and ionic conductivity (US’369, [0028]–[0034]). US’369 therefore teaches the use of the specific classes of organic cations recited in Claim 3 in the context of battery electrolytes.
WO’839, Zheng, and US’369 are all directed to ionic and phosphorus-containing compounds suitable for electrolyte or electrochemical applications, and each addresses material selection and ionic structure optimization for energy-related or functional compositions. Accordingly, the references are analogous art, as they pertain to the same field of endeavor and address the same problem of designing stable ionic compounds for electrolyte systems.
It would have been obvious to a person skilled in the art before the effective filing date of the instant application to modify the electrolyte compounds of WO’839 to employ organic cations ionically bonded to anions, such as imidazolium, pyrrolidinium, piperidinium, or ammonium, as taught by Zheng and US’369, because such organic ionic cations were well known, predictable choices for forming stable electrolyte salts and ionic liquids, and their selection would have involved no more than routine optimization and substitution of known equivalents to achieve the expected electrolyte performance.
Conclusion
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure.
US 20210036369 discloses imidazolium-based ionic liquids and related organic cations (Claims 3, 10, 11, 20).
Any inquiry concerning this communication or earlier communications from the examiner should be directed to JIMMY K VO whose telephone number is (571)272-3242. The examiner can normally be reached Monday - Friday, 8 am to 6 pm EST.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Tong Guo can be reached at (571) 272-3066. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/JIMMY VO/
Primary Examiner
Art Unit 1723
/JIMMY VO/Primary Examiner, Art Unit 1723