# US 12,218,306 B2 · Electrolyte for lithium secondary battery and lithium secondary battery including the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,218,306 B2 - Document ID: US12218306B2 - Status: Granted - Kind: B2 - Application number: 16/703,161 - Filed: 2019-12-04 - Published: 2020-06-11 - Granted: 2025-02-04 - Earliest claimed: 2018-12-10 - Assignees: SK On Co., Ltd. - Applicants: SK On Co., Ltd. - Inventors: Sung Yon Oh; Dong Gun Lee; Jin Haek Yang; In Haeng Cho - Web page: https://patentgrep.com/patent/US12218306B2 ## CPC - H01M 10/0567: characterised by the additives - H01M 4/505: of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy - H01M 4/525: of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy - H01M 10/0525: Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries - H01M 10/0568: characterised by the solutes - H01M 10/0569: characterised by the solvents - H01M 10/0565: Polymeric materials, e.g. gel-type or solid-type - Y02E 60/10: Energy storage using batteries - Y02P 70/50: Manufacturing or production processes characterised by the final manufactured product - H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION - Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS ## Abstract Provided are an electrolyte for a secondary battery including a lithium salt, a nonaqueous organic solvent, and a cyclic fluorophosphonate compound, and a lithium secondary battery including the same. ## Claims ### Claim 1 An electrolyte for a secondary battery, the electrolyte comprising: a lithium salt; a nonaqueous organic solvent; and a cyclic fluorophosphonate compound represented by the following Chemical Formula 1: wherein R1 and R2 are independently of each other hydrogen, C1-C10alkyl, halogen, C1-C10alkoxy, C3-C10cycloalkyl, or C6-C20aryl, and the alkyl, alkoxy, cycloalkyl, or aryl may be further substituted by one or more selected from the group consisting of C1-C10alkyl, halogen, haloC1-C10alkyl, C1-C10alkoxy, C1-C10alkoxyC1-C10alkyl, C3-C10cycloalkyl, and C6-C20aryl; A is —(CRaRb)m—, C3-C10cycloalkylene, or C6-C20arylene, and the cycloalkylene or arylene may be further substituted by one or more selected from the group consisting of C1-C10alkyl, halogen, haloC1-C10alkyl, C1-C10alkoxy, C1-C10alkoxyC1-C10alkyl, C3-C10cycloalkyl, and C6-C20aryl; Ra and Rb are independently of each other hydrogen, C1-C10alkyl, halogen, C1-C10alkoxy, C3-C10cycloalkyl, or C6-C20aryl, and the alkyl, alkoxy, cycloalkyl, or aryl may be further substituted by one or more selected from the group consisting of C1-C10alkyl, halogen, haloC1-C10alkyl, C1-C10alkoxy, C1-C10alkoxyC1-C10alkyl, C3-C10cycloalkyl, and C6-C20aryl; and m is an integer of 1 to 5. ### Claim 2 (depends on 1) The electrolyte for a secondary battery of claim 1, wherein the cyclic fluorophosphonate compound is a cyclic fluorophosphonate compound represented by the following Chemical Formula 2 or Chemical Formula 3: wherein R11, R12, R13, and R14 are independently of one another hydrogen, C1-C10alkyl, or halogen, and the alkyl may be further substituted by one or more selected from the group consisting of halogen, C1-C10alkoxy, C3-C10cycloalkyl, and C6-C20aryl; L1 is —(CRcRd)n—; Rc and Rd are independently of each other hydrogen, C1-C10alkyl, or halogen, and the alkyl may be further substituted by one or more selected from the group consisting of halogen, C1-C10alkoxy, C3-C10cycloalkyl, and C6-C20aryl; and n is an integer of 0 to 3, and p is an integer of 1 to 3. ### Claim 3 (depends on 1) The electrolyte for a secondary battery of claim 1, wherein the cyclic fluorophosphonate compound is a cyclic fluorophosphonate compound represented by the following Chemical Formula 4: wherein R11 to R16 are independently of one another hydrogen, C1-C7alkyl, halogen, or C1-C7alkoxyC1-C7alkyl. ### Claim 4 (depends on 1) The electrolyte for a secondary battery of claim 1, wherein the cyclic fluorophosphonate compound is one or more selected from the following structures: ### Claim 5 (depends on 1) The electrolyte for a secondary battery of claim 1, wherein the cyclic fluorophosphonate compound is comprised at 0.1 to 5.0 wt %, based on a total weight of the electrolyte. ### Claim 6 (depends on 1) The electrolyte for a secondary battery of claim 1, further comprising: one or two or more additives selected from the group consisting of oxalatoborate-based compounds, oxalatophosphate-based compounds, fluorine-substituted carbonate-based compounds, vinylidene carbonate-based compounds, and sulfinyl group-containing compounds. ### Claim 7 (depends on 1) The electrolyte for a secondary battery of claim 1, wherein the nonaqueous organic solvent is selected from the group consisting of cyclic carbonate-based solvents, linear carbonate-based solvents, and mixed solvents thereof. ### Claim 8 (depends on 7) The electrolyte for a secondary battery of claim 7, wherein the nonaqueous organic solvent has a mixed volume ratio of a linear carbonate solvent to a cyclic carbonate solvent of 1:1 to 9:1. ### Claim 9 (depends on 1) A lithium secondary battery comprising: a cathode, an anode, and the electrolyte for a secondary battery of claim 1. ### Claim 10 (depends on 9) The lithium secondary battery of claim 9, wherein the cathode includes a composite metal oxide of at least one transition metal selected from the group consisting of cobalt, manganese, and nickel with lithium as a cathode active material. ### Claim 11 (depends on 10) The lithium secondary battery of claim 10, wherein the cathode active material is a lithium-nickel-cobalt-manganese-based composite oxide. ### Claim 12 (depends on 11) The lithium secondary battery of claim 11, wherein the lithium-nickel-cobalt-manganese-based composite oxide is Lix(NiaCobMnc)O2 (0.5