A phase-changeable electrolyte material and application thereof

Abstract

The application relates to the technical field of lithium ion batteries, in particular to a phase-changeable electrolyte material and application thereof. The electrolyte material provided by the application comprises random copolymers, ionic liquid D, ionic liquid E, ether organic solvents, lithium salts and additives in specific proportions; the random copolymers are obtained by reversible addition-fragmentation chain transfer polymerization of monomer A, monomer B and monomer C in specific proportions; the monomer A is a styrene monomer; the monomer B is an aromatic alkyl isobutyrate monomer; the monomer C is a methyl acrylate monomer; the ionic liquid D is a 1-ethyl-3-methyl imidazolium fluorosulfonylimide salt; the cation of the ionic liquid E is E-I or E-II, and the anion is a fluorine-containing inorganic ion. The electrolyte material provided by the application has high-temperature safety and can realize high ionic conductivity at low temperature, and the phase change speed is fast.

Description

Technical Field

[0001] This invention relates to the field of lithium-ion battery technology, and in particular to a phase-change electrolyte material and its application. Background Technology

[0002] Lithium-ion batteries dominate applications in consumer electronics, new energy vehicles, and energy storage. Lithium battery electrolyte technology can be divided into liquid electrolytes and solid electrolytes. Currently, liquid electrolytes are the mainstream electrolytes in the market. Liquid electrolytes use a large amount of organic solvents, which can lead to a series of safety issues at high temperatures, such as electrolyte decomposition and vaporization. Moreover, these electrolytes are flammable, which poses a serious safety challenge to liquid electrolytes at high temperatures.

[0003] Solid-state electrolytes are considered a solution to improve battery safety, using non-flammable solid electrolytes instead of flammable organic solvents, including oxide, polymer, and sulfide routes. Solid-state electrolytes can significantly reduce the safety hazards associated with high-temperature thermal runaway and electrolyte combustion. However, solid-state electrolytes face performance issues at low temperatures; their ionic conductivity is very low at low temperatures, affecting the charge and discharge processes. Summary of the Invention

[0004] In view of this, the purpose of this invention is to provide a phase-change electrolyte material and its applications. The electrolyte material provided by this invention not only has high-temperature safety but also achieves high ionic conductivity at low temperatures.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a phase-change electrolyte material comprising 22-38 wt% random copolymer, 33-56 wt% ionic liquid D, 0.1-5 wt% ionic liquid E, 0.1-15 wt% ether organic solvent, 5-20 wt% lithium salt, and 0.1-5 wt% additives; The random copolymer is obtained by reversible addition-fragmentation chain transfer polymerization of monomer A (20-40 wt%), monomer B (10-30 wt%), and monomer C (40-50 wt%); monomer A is a styrene monomer; monomer B is an aromatic alkyl isobutyrate monomer; and monomer C is an alkyl methacrylate monomer. The ionic liquid D is a 1-ethyl-3-methylimidazolium-type fluorosulfonylimide salt; The cation of the ionic liquid E is E-I or E-II, and the anion is a fluorine-containing inorganic ion; E-Ⅰ、 E-Ⅱ.

[0006] Preferably, monomer A comprises styrene and / or p-methylstyrene.

[0007] Preferably, monomer B comprises benzyl isobutyrate and / or phenethyl isobutyrate.

[0008] Preferably, the monomer C comprises methyl methacrylate and / or ethyl methacrylate.

[0009] Preferably, the number-average molecular weight of the random copolymer is 60,000 to 120,000.

[0010] Preferably, the cation of the ionic liquid D is D-I and / or D-II; D-Ⅰ; D-II; The anions are selected from [TFSI]. - [FSI] - [TFSM] - [FTFSI] - and [CTFSI] - One or more of them.

[0011] Preferably, the ether organic solvent includes one or more of tetrahydrofuran, methyltetrahydrofuran, 1,1,2,2-tetrafluoroethyl-2,2,2-trifluoroethyl ether, 1,1,2,2-tetrafluoroethyl-2-methoxyethoxy ether, and 1,1,2,2-tetrafluoroethyl-2-(2,2,3,3-tetrafluoropropoxy)ethyl ether.

[0012] Preferably, the fluorine-containing inorganic ions include F - And / or [PF6] - .

[0013] Preferably, the additive comprises one or more of 1,2-bis(methyldifluorosilyl)ethane, 4-trifluoromethyl ethylene carbonate, dimethoxydiphenylsilane, and tert-butyldimethylsilyl glycidyl ether.

[0014] This invention provides the application of the electrolyte material described above in lithium-ion batteries.

[0015] The technical principle of this invention is as follows: In this invention, monomers A, B, and C are synthesized into a random copolymer via reversible addition-fragmentation chain transfer (RAFT) polymerization. The random copolymer and ionic liquid D maintain an elastic gel state due to the formation of a network structure (not the LCST phenomenon; LCST refers to the critical temperature at which a polymer solution transitions from a homogeneous state to a phase-separated state, i.e., the minimum eutectic temperature). The segments formed by monomers A and C in the random copolymer form a network structure with ionic liquid D. The segments formed by the self-polymerization of monomer B themselves exhibit the LCST phenomenon. This invention controls the proportions of monomers A, B, and C in the polymer. When the temperature is below the LCST temperature of monomer B self-polymerization, the electrolyte system exhibits the properties of monomer B self-polymerization itself (dissolving in ionic liquid D). That is, at low temperatures, the electrolyte system is in a liquid state with high ionic conductivity. When the temperature rises to a certain level, the electrolyte system precipitates an ionic gel, blocking the battery reaction and preventing further temperature increases, thereby protecting the battery.

[0016] Furthermore, the ionic liquid E and ether-based organic solvents in the electrolyte system inhibit the intermolecular compatibility between the random copolymer and the ionic liquid D. The phase transition temperature and rate of the electrolyte system can be controlled by adjusting the content of ionic liquid E and ether-based organic solvents. In practical applications, a slow phase transition rate can prevent the electrolyte from promptly preventing further thermal runaway of the battery, thus failing to achieve the battery's high-temperature safety target. This invention, by introducing ionic liquid E and ether-based organic solvents and controlling their content, can rapidly adjust the phase transition temperature while controlling the phase transition time to 2 to 5 minutes, achieving rapid phase transition of the electrolyte. Attached Figure Description

[0017] Figure 1 The curves show the transmittance of the electrolytes in Examples 1-5 as a function of time. Detailed Implementation

[0018] This invention provides a phase-change electrolyte material comprising 22-38 wt% random copolymer, 33-56 wt% ionic liquid D, 0.1-5 wt% ionic liquid E, 0.1-15 wt% ether organic solvent, 5-20 wt% lithium salt, and 0.1-5 wt% additives; The random copolymer is obtained by reversible addition-fragmentation chain transfer polymerization of monomer A (20-40 wt%), monomer B (10-30 wt%), and monomer C (40-50 wt%); monomer A is a styrene monomer; monomer B is an aromatic alkyl isobutyrate monomer; and monomer C is an alkyl methacrylate monomer. The ionic liquid D is a 1-ethyl-3-methylimidazolium-type fluorosulfonylimide salt; The cation of the ionic liquid E is E-I or E-II, and the anion is a fluorine-containing inorganic ion; E-Ⅰ、 E-Ⅱ.

[0019] Unless otherwise specified, all raw materials used in this invention are commercially available products well known in the art.

[0020] The following section will first explain random copolymers.

[0021] In this invention, the random copolymer is obtained by reversible addition-fracture chain transfer polymerization of monomer A (20-40 wt%), monomer B (10-30 wt%), and monomer C (40-50 wt%).

[0022] In a specific embodiment, the proportion of monomer A can be 20, 22, 25, 28, 30, 32, 35, 38 or 40 wt%; the proportion of monomer B can be 10, 15, 18, 20, 22, 25, 28 or 30 wt%; and the proportion of monomer C can be 40, 43, 45, 48 or 50 wt%.

[0023] In this invention, monomer A is a styrene monomer, preferably including styrene and / or p-methylstyrene; monomer B is an aromatic alkyl isobutyrate monomer, preferably including benzyl isobutyrate and / or ethyl isobutyrate; and monomer C is an alkyl methacrylate monomer, preferably including methyl methacrylate and / or ethyl methacrylate.

[0024] In this invention, the number average molecular weight of the random copolymer is preferably 60,000 to 120,000, and in specific embodiments it can be 60,000, 68,000, 75,000, 80,000, 90,000, 94,000, 100,000, 110,000, 116,000 or 120,000.

[0025] In this invention, the reaction temperature of the reversible addition-fragmentation chain transfer polymerization is preferably 80°C. This invention does not impose any special limitations on the implementation process of the reversible addition-fragmentation chain transfer polymerization; any implementation process well known in the art can be used.

[0026] In an embodiment of the present invention, the method for preparing the random copolymer preferably includes the following steps: mixing monomer A, monomer B, monomer C, RAFT reagent and initiator, purging the resulting reaction mixture with argon at room temperature, and then carrying out reversible addition-fragmentation chain transfer polymerization under stirring at 80°C, and post-processing the resulting reaction product system to obtain the random copolymer.

[0027] In this invention, the RAFT reagent is preferably 2-phenyl-2-propylbenzodisulfide; the amount of the RAFT reagent is preferably 0.005~0.010% of the mass of monomer A, and in a specific embodiment it is 0.008%; the initiator is preferably azobisisobutyronitrile (AIBN); the amount of the initiator is preferably 0.015~0.020% of the mass of monomer A, and in a specific embodiment it is 0.016%.

[0028] In this invention, the post-processing preferably includes the following steps: adding excess methanol dropwise to the reaction product system to precipitate the random copolymer, then filtering, and drying the resulting wet solid to obtain the random copolymer.

[0029] The formulation of the phase-change electrolyte material is described below.

[0030] The electrolyte material provided by the present invention comprises 22-38 wt% random copolymer, which can be 22, 24, 26, 28, 30, 32, 34, 36 or 38 wt% in specific embodiments.

[0031] The electrolyte material provided by this invention comprises ionic liquid D at 33-56 wt%, which in specific embodiments can be 33, 39, 40, 45, 50, 53, or 56 wt%. In this invention, the ionic liquid D is a 1-ethyl-3-methylimidazolium fluorosulfonylimide salt; the cation of the ionic liquid D is preferably D-I and / or D-II; D-Ⅰ; D-II; The anions are preferably selected from [TFSI]. - [FSI] - [TFSM] - [FTFSI] - and [CTFSI] - One or more of the following. In this invention, the interaction between the random copolymer and the ionic liquid D endows the electrolyte material with phase change properties. Specifically, the random copolymer and the ionic liquid D can form a network structure while maintaining an elastic gel state (not the LCST phenomenon). The segments formed by monomers A and C in the random copolymer form a network structure with the ionic liquid D. The segments formed by the self-polymerization of monomer B themselves exhibit the LCST phenomenon. This invention controls the proportions of monomers A, B, and C in the polymer. When the temperature is lower than the LCST temperature of monomer B self-polymerization, the electrolyte system exhibits the properties of monomer B self-polymerization itself (dissolving in ionic liquid D). That is, at low temperatures, the electrolyte system is in a liquid state. When the temperature rises to a certain level, the electrolyte system precipitates an ionic gel, blocking the battery reaction and preventing further increases in battery temperature, thereby protecting the battery.

[0032] The electrolyte material provided by this invention comprises an ionic liquid E at a concentration of 0.1-5 wt%, which in specific embodiments can be 0.1, 0.5, 1, 1.5, 2, 3, 4, or 5 wt%. In this invention, the cation of the ionic liquid E is E-I or E-II, and the anion is a fluorine-containing inorganic ion, preferably including F. - And / or [PF6] - .

[0033] E-Ⅰ、 E-Ⅱ.

[0034] The electrolyte material provided by this invention comprises 0.1~15wt% of an ether-based organic solvent, which in specific embodiments can be 0.1, 1, 3, 5, 7, 8, 9, 10, 11, 12, 14, or 15wt%. In this invention, the ether-based organic solvent preferably comprises one or more of tetrahydrofuran, methyltetrahydrofuran, 1,1,2,2-tetrafluoroethyl-2,2,2-trifluoroethyl ether, 1,1,2,2-tetrafluoroethyl-2-methoxyethoxy ether, and 1,1,2,2-tetrafluoroethyl-2-(2,2,3,3-tetrafluoropropoxy)ethyl ether.

[0035] In this invention, the ionic liquid E and the ether-based organic solvent suppress the intermolecular compatibility between the random copolymer and the ionic liquid D. By controlling the content of both, this invention can rapidly adjust the phase transition temperature and control the phase transition time to 2 to 5 minutes, achieving rapid phase transition of the electrolyte. In practical applications, if the phase transition rate is too slow, the electrolyte will be unable to prevent further thermal runaway of the battery in time, thus failing to achieve the battery's high-temperature safety target. The electrolyte material provided by this invention, through the synergistic combination of various formulations, not only achieves high-temperature phase transition but also has a fast phase transition rate, ensuring the high-temperature safety of the battery.

[0036] The electrolyte material provided by this invention comprises 5-20 wt% lithium salt, which in specific embodiments can be 6, 8, 10, 12, 15, 17, or 20 wt%. In this invention, the lithium salt preferably comprises one or more of LiPF6, LiBF4, LiTFSI, LiBOB, LiDFOB, LiCF3SO3, and LiClO4.

[0037] The electrolyte material provided by this invention includes 0.1-5 wt% additives, which in specific embodiments can be 0.1, 0.5, 1, 1.5, 1.9, 2, 3, 4, or 5 wt%. In this invention, the additives preferably include one or more of 1,2-bis(methyldifluorosilyl)ethane, 4-trifluoromethyl ethylene carbonate, dimethoxydiphenylsilane, and tert-butyldimethylsilyl glycidyl ether. In this invention, the additives function to reduce the viscosity of the system, improve ionic conductivity, and simultaneously protect the CEI / SEI films of the positive and negative electrodes of the battery.

[0038] The present invention does not have any special requirements for the preparation method of the electrolyte material; the components can be mixed evenly directly.

[0039] This invention provides the application of the electrolyte material described above in lithium-ion batteries.

[0040] The following detailed description of the gel electrolyte, its preparation method, and its application provided by the present invention, with reference to specific embodiments, should not be construed as limiting the scope of protection of the present invention.

[0041] The preparation processes of the random copolymers in the following examples and comparative examples are as follows, with the only difference being the monomer ratio: Monomers A, B, and C, RAFT reagent (2-phenyl-2-propylbenzodisulfide, 0.008% by mass of monomer A), and initiator AIBN (0.016% by mass of monomer A) were added to a dry three-necked flask. The reaction mixture was purged with argon at room temperature for 1–2 hours, and then stirred at 80°C for 6–8 hours. The reaction was then terminated by adding liquid nitrogen. The resulting solution was precipitated by adding excess methanol dropwise. The polymer was filtered, collected, and dried under low pressure at 50–60°C to obtain a random copolymer. The process of filtration, collection, and low-pressure drying was repeated three to five times for further purification.

[0042] The structural formulas of the raw materials used in the following embodiments and comparative examples are as follows: Monomer A(Ⅰ) is styrene, and monomer A(Ⅱ) is p-methylstyrene; monomer B(Ⅰ) is benzyl isobutyrate, and monomer B(Ⅱ) is ethyl isobutyrate; monomer C(Ⅰ) is methyl methacrylate, and monomer C(Ⅱ) is ethyl methacrylate; Monomer A(Ⅰ); Monomer A(II); Monomer B(Ⅰ); Monomer B(II); Monomer C(Ⅰ); Monomer C(II); D-Ⅰ; D-II; E-Ⅰ、 E-Ⅱ.

[0043] Example 1: 30wt% monomer A (Ⅰ), 22wt% monomer B (Ⅰ), and 48wt% monomer C (Ⅰ) were polymerized into a random copolymer (1) with a number average molecular weight of 94,000.

[0044] In an argon-filled glove box, 26 wt% random copolymer (1) and 39 wt% ionic liquid D (cation: D-I, anion: [TFSI]) were mixed. - ), 5wt% ionic liquid E (cation is E-I, anion is [PF6) - 12wt% methyltetrahydrofuran, 9wt% LiDFOB, 6wt% LiBOB, and 3wt% 4-trifluoromethyl ethylene carbonate were mixed to form an electrolyte. The mixed electrolyte was placed on a stirring device and stirred for 30 minutes to obtain the target electrolyte.

[0045] Example 2: 25wt% monomer A (Ⅰ), 30wt% monomer B (Ⅱ), and 45wt% monomer C (Ⅰ) were polymerized into a random copolymer (2) with a number average molecular weight of 68,000.

[0046] In an argon-filled glove box, 30 wt% copolymer (2) and 40 wt% ionic liquid D (cation: D-I, anion: [TFSI]) were added. - ), 4wt% ionic liquid E (cation is E-II, anion is F), - 11wt% methyltetrahydrofuran, 13wt% LiBF4, and 2wt% 1,2-bis(methyldifluorosilyl)ethane were mixed to form an electrolyte. The mixed electrolyte was placed on a stirring device and stirred for 30 minutes to obtain the target electrolyte.

[0047] Example 3: 20 wt% monomer A(II), 30 wt% monomer B(II), and 50 wt% monomer C(II) were polymerized into a random copolymer (3) with a number average molecular weight of 116,000. In an argon-filled glove box, 32 wt% copolymer (2) and 45 wt% ionic liquid D (cation: D-II, anion: [FSI]) were added. - ), 4wt% ionic liquid E (cation is E-II, anion is PF6) - 9wt% tetrahydrofuran, 4wt% LiPF6, 4wt% LiBF4, and 2wt% tert-butyldimethylsilyl glycidyl ether were mixed to form an electrolyte. The mixed electrolyte was placed on a stirring device and stirred for 30 minutes to obtain the target electrolyte.

[0048] Example 4: 35 wt% monomer A(II), 25 wt% monomer B(I), and 40 wt% monomer C(II) were polymerized into a random copolymer (4) with a number average molecular weight of 110,000. In an argon-filled glove box, 34 wt% copolymer (2) and 45 wt% ionic liquid D (cation: D-I, anion: [FSI]) were added. - ), 2wt% ionic liquid E (cation is E-I, anion is F), - 10wt% 1,1,2,2-tetrafluoroethyl-2,2,2-trifluoroethyl ether, 6wt% LiTFSI, and 3wt% dimethoxydiphenylsilane were mixed to form an electrolyte. The mixed electrolyte was placed on a stirring device and stirred for 30 minutes to obtain the target electrolyte.

[0049] Example 5: 40 wt% monomer A (Ⅰ), 20 wt% monomer B (Ⅰ), and 40 wt% monomer C (Ⅱ) were polymerized into a random copolymer (5) with a number average molecular weight of 106,000. In an argon-filled glove box, 30 wt% copolymer (2) and 50 wt% ionic liquid D (cation: D-Ⅰ, anion: [TFSM]) were added. - ), 0.1 wt% ionic liquid E (cation is E-I, anion is [PF6) - 8wt% tetrahydrofuran, 10wt% LiCF3SO3, and 1.9wt% 1,2-bis(methyldifluorosilyl)ethane were mixed to form an electrolyte. The mixed electrolyte was placed on a stirring device and stirred for 30 minutes to obtain the target electrolyte.

[0050] Comparative Example 1: The difference between Comparative Example 1 and Example 1 lies in the structural formula of monomer A(Ⅰ) used to synthesize the random copolymer. The structural formula of the monomer in Comparative Example 1 is as follows: .

[0051] Comparative Example 2: The difference between Comparative Example 2 and Example 2 is that it does not contain ionic liquid D.

[0052] Comparative Example 3: The difference between Comparative Example 3 and Example 3 is that it does not contain ionic liquid E.

[0053] Comparative Example 4: The difference between Comparative Example 4 and Example 4 is that the organic solvent 1,1,2,2-tetrafluoroethyl-2,2,2-trifluoroethyl ether is not present.

[0054] Comparative Example 5 The difference between Comparative Example 5 and Example 1 is that the synthesized random copolymer does not contain monomer B.

[0055] The electrolytes prepared in the above embodiments and comparative examples were added to a battery casing with lithium iron phosphate as the positive electrode, lithium as the negative electrode and polyvinylidene fluoride as the separator, and assembled into a lithium battery. The ionic conductivity, discharge capacity, phase transition temperature and phase transition time were then tested.

[0056] Phase transition temperature test: The phase transition temperature of an electrolyte is determined by measuring the transmittance of the electrolyte solution. A variable-temperature ultraviolet-visible spectrometer is used to measure the transmittance of the electrolyte solution. The solution is placed on the instrument's heating stage and heated at a rate of 1℃ / min. The transmittance curve is recorded, and the temperature at which the transmittance reaches 10% is defined as the phase transition temperature.

[0057] Phase transition time test: The transmittance of the electrolyte solution was determined using a variable-temperature ultraviolet-visible spectrometer. The solution was placed on the instrument's heating stage and heated at a rate of 1 °C / min. The transmittance curve was recorded, and the time required for the transmittance of the electrolyte solution to decrease from 90% to 10% was defined as the phase transition time. Figure 1 The curves show the transmittance of the electrolytes in Examples 1-5 as a function of time.

[0058] Ion conductivity test: With an area of ​​2 cm 2 A battery is assembled from a stainless steel gasket and an electrolyte. The battery is placed in a low-temperature test chamber at 25°C for 3 hours. An electrochemical workstation is connected, and a sinusoidal voltage signal with an amplitude of 20 mV is applied. The test frequency range is between 4 MHz and 100 MHz. The resistance of the electrolyte is recorded, and the ionic conductivity is calculated.

[0059] Discharge capacity test: The assembled battery was placed in a high and low temperature test chamber with the temperature set to 25℃. The battery was left to stand for 1 hour, then connected to a charge and discharge instrument and discharged at a rate of 0.2 C with a discharge cutoff voltage of 2 V. The capacity of the first discharge at 25℃ was recorded.

[0060] The test results of each embodiment and comparative example are summarized in Table 1.

[0061] Table 1 Performance test results of the examples and comparative examples

[0062] Note: In Table 1, “——” indicates that no phase transition occurs.

[0063] As shown in Table 1, the electrolyte provided by this invention exhibits high ionic conductivity and high discharge capacity at low temperatures (25°C). It can undergo a phase transition at high temperatures, with the phase transition temperature adjustable between 50 and 100°C, and the phase transition speed is fast, with a phase transition time of only 2 to 5 minutes, significantly improving the safety of lithium-ion batteries. In contrast, Comparative Examples 1 and 5 do not undergo phase transitions because the polymer does not produce the LCST phenomenon with ionic liquid D; Comparative Example 2 does not undergo a phase transition because ionic liquid D is absent; Comparative Example 3, lacking ionic liquid E, cannot suppress the intermolecular compatibility between the random copolymer and ionic liquid D, thus failing to control the phase transition temperature and rate of the electrolyte system; and Comparative Example 4, lacking ether-based organic solvents, has a high system viscosity, which affects the system's conductivity.

[0064] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A phase-change electrolyte material, characterized in that, It includes 22-38 wt% random copolymer, 33-56 wt% ionic liquid D, 0.1-5 wt% ionic liquid E, 0.1-15 wt% ether organic solvent, 5-20 wt% lithium salt, and 0.1-5 wt% additives; The random copolymer is obtained by reversible addition-fragmentation chain transfer polymerization of monomer A (20-40 wt%), monomer B (10-30 wt%), and monomer C (40-50 wt%); monomer A is a styrene monomer; monomer B is an aromatic alkyl isobutyrate monomer; and monomer C is an alkyl methacrylate monomer. The ionic liquid D is a 1-ethyl-3-methylimidazolium-type fluorosulfonylimide salt; The cation of the ionic liquid E is E-I or E-II, and the anion is a fluorine-containing inorganic ion; E-Ⅰ、 E-Ⅱ。 2. The electrolyte material according to claim 1, characterized in that, The monomer A includes styrene and / or p-methylstyrene.

3. The electrolyte material according to claim 1, characterized in that, The monomer B includes benzyl isobutyrate and / or phenyl isobutyrate.

4. The electrolyte material according to claim 1, characterized in that, The monomer C includes methyl methacrylate and / or ethyl methacrylate.

5. The electrolyte material according to any one of claims 1 to 4, characterized in that, The number average molecular weight of the random copolymer is 60,000 to 120,000.

6. The electrolyte material according to claim 1, characterized in that, The cations of the ionic liquid D are D-I and / or D-II; D-Ⅰ; D-Ⅱ; The anions are selected from [TFSI]. - [FSI] - [TFSM] - [FTFSI] - and [CTFSI] - One or more of them.

7. The electrolyte material according to claim 1, characterized in that, The ether organic solvents include one or more of tetrahydrofuran, methyltetrahydrofuran, 1,1,2,2-tetrafluoroethyl-2,2,2-trifluoroethyl ether, 1,1,2,2-tetrafluoroethyl-2-methoxyethoxy ether, and 1,1,2,2-tetrafluoroethyl-2-(2,2,3,3-tetrafluoropropoxy)ethyl ether.

8. The electrolyte material according to claim 1, characterized in that, The fluorine-containing inorganic ions include F - And / or [PF6] - .

9. The electrolyte material according to claim 1, characterized in that, The additives include one or more of 1,2-bis(methyldifluorosilyl)ethane, 4-trifluoromethyl ethylene carbonate, dimethoxydiphenylsilane, and tert-butyldimethylsilyl glycidyl ether.

10. The application of the electrolyte material according to any one of claims 1 to 9 in a lithium-ion battery.

Images