CN114464890B - Non-combustible electrolyte and lithium metal battery based on same - Google Patents

Non-combustible electrolyte and lithium metal battery based on same Download PDF

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CN114464890B
CN114464890B CN202210167022.1A CN202210167022A CN114464890B CN 114464890 B CN114464890 B CN 114464890B CN 202210167022 A CN202210167022 A CN 202210167022A CN 114464890 B CN114464890 B CN 114464890B
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electrolyte
combustible
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fluoroether
ether
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CN114464890A (en
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任晓迪
陈黎
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University of Science and Technology of China USTC
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
    • H01M10/0564—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of organic materials only
    • H01M10/0566—Liquid materials
    • H01M10/0567—Liquid materials characterised by the additives
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
    • H01M10/4235—Safety or regulating additives or arrangements in electrodes, separators or electrolyte
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M2300/00—Electrolytes
    • H01M2300/0017—Non-aqueous electrolytes
    • H01M2300/0025—Organic electrolyte
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    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
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Abstract

The invention discloses a non-combustible electrolyte and a lithium metal battery based on the same, wherein the non-combustible electrolyte comprises a solvent, electrolyte salt and fluoroether flame retardant, the solvent comprises at least one of ether, ester and sulfone solvents, the electrolyte salt comprises at least two of lithium salts containing different anions, and the fluoroether flame retardant comprises fluoroether with the F/H molar ratio of more than or equal to 3. The non-combustible electrolyte can improve the safety performance of the lithium metal battery, has good compatibility with a negative electrode, and can improve the cycling stability of a high-voltage positive electrode.

Description

Non-combustible electrolyte and lithium metal battery based on same
Technical Field
The invention relates to the technical field of lithium metal batteries, in particular to a non-combustible electrolyte and a lithium metal battery based on the non-combustible electrolyte.
Background
Rechargeable lithium metal batteries equipped with high voltage positive electrodes have a higher energy density than lithium ion batteries and are therefore receiving extensive attention from academic and industrial researchers. Lithium metal has an ultra-high theoretical specific capacity (3830 mAh g -1) and an ultra-low electrochemical redox potential (-3.04V vs. standard hydrogen electrode) as the negative electrode. The safety and stability problems of lithium metal batteries remain a significant challenge for their commercial application. Most of the electrolytes available today are highly flammable and overcharging, shorting or high thermal shock of the battery may create a more serious explosion hazard. In addition, the nickel-rich layered cathode material has a large amount of high-activity Ni 4+ ions in a lithium removal state, and can generate serious side reaction with electrolyte under high pressure, which further aggravates the thermal runaway reaction of the battery.
The addition of a phosphate solvent (such as trimethyl phosphate) with flame retardance to the electrolyte is expected to solve the problem of safety of lithium metal batteries. However, all of these phosphate solvents have a high intrinsic reactivity with lithium metal, which results in poor stability of the lithium metal battery. The use of high concentration phosphate electrolytes to limit the number of free solvent molecules can improve the stability of lithium metal batteries to some extent. However, due to the high reactivity inherent between phosphate molecules and lithium metal, developing lithium metal batteries based on phosphate electrolytes remains a formidable challenge.
Compared with other solvents, the ether molecules have better compatibility with lithium metal. However, common ether molecules are highly flammable, and suppression of free ether molecules by preparing high concentrations of electrolytes can only reduce their flammability to a limited extent. In order to reduce the inherent combustibility of ether molecules, substitution of active hydrogen atoms in ether molecules with fluorine atoms is an effective method. Such as bis (2, 2-trifluoroethyl) ether (F/H molar ratio=1.5, flash point=1℃ C.) and 1, 2-tetrafluoroethyl-2, 3-tetrafluoropropyl ether (F/H molar ratio=2, flash point=27.5℃ C.) have been successfully added to high concentration electrolytes. Because of the electron withdrawing effect of fluorine atoms, these fluoroethers are difficult to participate in Li + solvation, and therefore do not destroy the solvation structure of high salt/solvent ratio, thereby successfully preserving the electrochemical properties of the high-concentration electrolyte. However, the F/H molar ratio and flash point of the fluorinated ethers reported so far are low, and still have high combustibility. To solve this problem, the F/H molar ratio of the fluoroether can be increased, but the addition of fluoroether having a high F/H molar ratio (F/H molar ratio. Gtoreq.3) to the electrolyte causes the phase separation of the electrolyte. Therefore, how to achieve the addition of fluoroethers with high F/H molar ratios to the electrolyte without causing phase separation of the electrolyte is a critical issue that needs to be addressed.
Disclosure of Invention
In view of the above, the present invention provides a non-combustible electrolyte and a lithium metal battery based thereon, so as to improve the safety of the electrolyte and provide the lithium metal battery based thereon with excellent performance.
The invention adopts the following technical scheme to solve the technical problems:
The invention firstly provides a non-combustible electrolyte, which comprises a solvent, electrolyte salt and fluoroether flame retardant, wherein: the solvent comprises at least one of an ether solvent, an ester solvent and a sulfone solvent; the electrolyte salt includes at least two of lithium salts containing different anions; the fluoroether flame retardant comprises fluoroether with F/H molar ratio more than or equal to 3.
Further: the ether solvent mainly comprises at least one of ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, tetrahydrofuran and 1, 3-dioxane; the ester solvent mainly comprises at least one of methyl ethyl carbonate, ethylene carbonate, propylene carbonate, butylene carbonate, vinylene carbonate, dimethyl carbonate, diethyl carbonate and gamma-butyrolactone; the sulfone solvent mainly comprises at least one of sulfolane, dimethyl sulfone and dimethyl sulfoxide.
Further, the electrolyte salt includes at least two of lithium bis (trifluoromethanesulfonyl) imide, lithium bis (pentafluoroethylsulfonyl) imide, lithium bis (heptafluoropropylsulfonyl) imide, and lithium bis (nonafluorobutylsulfonyl) imide.
Further, the fluoroether flame retardant mainly comprises at least one of methyl nonafluorobutyl ether (F/H molar ratio is 3), 2- (trifluoromethyl) -3-ethoxy-1,1,1,2,3,4,4,5,5,6,6,6-dodecafluoro-2- (trifluoromethyl) -hexane (F/H molar ratio is 3) and 1,2,3,4, 5-decafluoro-3-methoxy-4- (trifluoromethyl) pentane (F/H molar ratio is 4.33).
Further, in the electrolyte, the mol ratio of the solvent to the fluoroether flame retardant is 1:0.1-10, and the mol ratio of the electrolyte salt to the solvent is 1:0.5-10.
Furthermore, the electrolyte phase separation problem is solved by balancing the hydrogen bonding action between fluoroether flame retardant/anion/solvent in the electrolyte by regulating the proportion of the electrolyte salt while considering the electrochemical performance of the electrolyte, wherein the electrolyte salt has various proportion schemes, and the mole percentage of the carbon-fluorine chain-containing salt is not less than 50%, for example: the electrolyte salt can be compounded by lithium bis (pentafluoroethylsulfonyl) imide and lithium bis (fluorosulfonyl) imide according to the molar ratio of 1:0.1-1; the electrolyte salt can be compounded by lithium bis (pentafluoroethylsulfonyl) imide and lithium bis (trifluoromethanesulfonyl) imide according to the molar ratio of 1:0.1-1; the electrolyte salt can be compounded by lithium bis (trifluoromethanesulfonyl) imide and lithium bis (fluorosulfonyl) imide according to the mol ratio of 1:0.1-1; the electrolyte salt can be compounded by lithium bis (heptafluoropropylsulfonyl) imide and lithium bis (fluorosulfonyl) imide according to the mol ratio of 1:0.1-1; the electrolyte salt can be compounded by lithium bis (nonafluorobutylsulfonyl) imide and lithium bis (fluorosulfonyl) imide according to the mol ratio of 1:0.1-1.
The invention also provides a lithium metal battery adopting the non-combustible electrolyte.
Compared with the prior art, the invention has the beneficial effects that:
1. The fluoroether flame retardant in the non-combustible electrolyte has high F/H molar ratio and high flash point due to the molecular structure characteristic, so that the safety performance of the electrolyte is greatly improved. Meanwhile, the low dielectric constant of the fluoroether flame retardant reduces the viscosity of the electrolyte and improves the wettability of the electrolyte.
2. The electrolyte salt in the non-combustible electrolyte provided by the invention balances the hydrogen bonding effect between fluoroether flame retardant/anions/solvents in the electrolyte by adjusting the composition of the electrolyte salt and controlling the addition proportion of different anion electrolyte salts while considering the electrochemical performance of the electrolyte, thereby solving the problem of electrolyte phase separation caused by adding fluoroether with high F/H molar ratio.
3. The non-combustible electrolyte can realize dendrite-free deposition growth and high coulomb efficiency of the lithium metal cathode and stability on the surface of the high-voltage anode.
4. The lithium metal battery adopting the non-combustible electrolyte provided by the invention has the advantages that the initial/peak temperature and the heat release quantity of the lithium-removing anode and the electrolyte which are in thermal runaway are obviously improved compared with those of the traditional ester electrolyte, and the performance of the lithium metal battery is obviously improved.
Drawings
FIG. 1 is a photograph showing the electrolyte obtained in example 2 and example 3;
FIG. 2 is a photograph showing the electrolyte obtained in example 4 and example 6;
FIG. 3 is a comparative graph of ignition experiments of the electrolytes obtained in examples 1, 5 and 6;
FIG. 4 is a graph showing comparison of coulombic efficiencies of lithium metal cathodes for the conventional electrolyte of example 1 and the non-combustible ether electrolyte of example 6;
FIG. 5 is a graph showing the morphology of the copper foil surface (first column) and the thickness of deposited lithium on the copper foil surface (second column) after the cycle of the conventional electrolyte in example 1 and the Li/Cu half-cell of the non-combustible ether electrolyte in example 6;
FIG. 6 is a graph showing the cycle performance of a lithium metal battery assembled from the conventional electrolyte of example 1 and the non-combustible ether electrolyte of example 6;
FIG. 7 is a graph showing the comparison of the rate performance of lithium metal batteries assembled from the conventional electrolyte of example 1 and the non-combustible ether electrolyte of example 6;
FIG. 8 is a differential scanning calorimetric experiment comparison of the conventional electrolyte of example 1 and the non-combustible ether electrolyte of example 6 mixed with the delithiated positive electrode.
Detailed Description
The present invention will be further described in detail below with reference to specific embodiments and with reference to the accompanying drawings, in order to make the objects, technical solutions and advantages of the present invention more apparent.
The invention provides a non-combustible electrolyte, which comprises a solvent, electrolyte salt and fluoroether flame retardant, wherein: the solvent comprises at least one of an ether solvent, an ester solvent and a sulfone solvent, the ether solvent mainly comprises at least one of ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, tetrahydrofuran and 1, 3-dioxane, the ester solvent mainly comprises at least one of methyl ethyl carbonate, ethylene carbonate, propylene carbonate, butylene carbonate, vinylene carbonate, dimethyl carbonate, diethyl carbonate and gamma-butyrolactone, and the sulfone solvent mainly comprises at least one of sulfolane, dimethyl sulfone and dimethyl sulfoxide. The electrolyte salt includes at least two of lithium bis (trifluoromethanesulfonyl) imide, lithium bis (pentafluoroethylsulfonyl) imide, lithium bis (heptafluoropropylsulfonyl) imide, and lithium bis (nonafluorobutylsulfonyl) imide. The fluoroether flame retardant comprises at least one of methyl nonafluorobutyl ether (F/H molar ratio is 3), 2- (trifluoromethyl) -3-ethoxy-1,1,1,2,3,4,4,5,5,6,6,6-dodecafluoro-2- (trifluoromethyl) -hexane and 1,2,3,4, 5-decafluoro-3-methoxy-4- (trifluoromethyl) pentane (F/H molar ratio is 4.33).
According to the embodiment of the invention, the electrolyte phase separation problem is solved by balancing the hydrogen bonding action between fluoroether flame retardant/anion/solvent in the electrolyte by regulating the proportion of the electrolyte salt while considering the electrochemical performance of the electrolyte, wherein the electrolyte salt has a plurality of proportion schemes, and the mole percentage of the carbon-fluorine chain salt is not less than 50%, and the feasible partial schemes comprise: the lithium bis (pentafluoroethylsulfonyl) imide and lithium bis (fluorosulfonyl) imide can be compounded into electrolyte salts according to the molar ratio of 1:0.1-1, for example, 1:0.1;1:0.2;1:0.3;1:0.4;1:0.5;1:0.6;1:0.7;1:0.8;1:0.9;1:1; the electrolyte salt can be compounded by lithium bis (pentafluoroethylsulfonyl) imide and lithium bis (trifluoromethanesulfonyl) imide according to the molar ratio of 1:0.1-1, for example, 1:0.1;1:0.2;1:0.3;1:0.4;1:0.5;1:0.6;1:0.7;1:0.8;1:0.9;1:1; the electrolyte salt can be compounded by lithium bis (trifluoromethanesulfonyl) imide and lithium bis (fluorosulfonyl) imide according to the mol ratio of 1:0.1-1, for example, 1:0.1;1:0.2;1:0.3;1:0.4;1:0.5;1:0.6;1:0.7;1:0.8;1:0.9;1:1; the lithium bis (heptafluoropropylsulfonyl) imide and lithium bis (fluorosulfonyl) imide can be compounded into electrolyte salt according to the molar ratio of 1:0.1-1, for example, 1:0.1;1:0.2;1:0.3;1:0.4;1:0.5;1:0.6;1:0.7;1:0.8;1:0.9;1:1; the electrolyte salt can be compounded by lithium bis (nonafluorobutylsulfonyl) imide and lithium bis (fluorosulfonyl) imide according to the mol ratio of 1:0.1-1, for example, 1:0.1;1:0.2;1:0.3;1:0.4;1:0.5;1:0.6;1:0.7;1:0.8;1:0.9;1:1.
According to an embodiment of the invention, the molar ratio of the solvent to the fluoroether flame retardant in the electrolyte is 1:0.1-10, for example: 1:0.1;1:0.5;1:1;1:2;1:5;1:10.
According to an embodiment of the present invention, the molar ratio of the electrolyte salt and the solvent in the electrolyte is 1:0.5-10, for example: 1:0.5;1:1;1:2;1:5;1:10.
The fluoroether flame retardant in the non-combustible electrolyte has high F/H molar ratio and high flash point due to the molecular structure characteristic, so that the safety performance of the electrolyte is greatly improved. Meanwhile, the low dielectric constant of the fluoroether flame retardant reduces the viscosity of the electrolyte, forms a solvated structure with local high concentration, and improves the wettability of the electrolyte. The electrolyte salt in the non-combustible electrolyte solves the problem of electrolyte phase separation caused by adding fluoroether with high F/H molar ratio by adjusting the composition of the electrolyte salt and controlling the adding proportion of different anionic electrolyte salts.
The technical effects of the present invention are further described below in connection with specific examples and test characterizations thereof.
Example 1
The traditional carbonate electrolyte is prepared, and the composition is as follows: the solvent is ethylene carbonate and methyl ethyl carbonate, the electrolyte salt is lithium hexafluorophosphate, the additive is vinylene carbonate, and the prepared electrolyte is lithium hexafluorophosphate (1.0 mol/L) dissolved in the ethylene carbonate/methyl ethyl carbonate (mass ratio is 3:7) plus the mass fraction of 2% vinylene carbonate.
Example 2
Preparing a non-combustible ether electrolyte, which comprises the following components: the solvent is ethylene glycol dimethyl ether, the electrolyte salt is lithium bis (fluorosulfonyl) imide, the fluoroether flame retardant is methyl nonafluorobutyl ether, and the prepared electrolyte is lithium bis (fluorosulfonyl) imide/ethylene glycol dimethyl ether/methyl nonafluorobutyl ether (the molar ratio is 1:2:2).
Example 3
Preparing a non-combustible ether electrolyte, which comprises the following components: the solvent is ethylene glycol dimethyl ether, the electrolyte salt is lithium bis (trifluoromethanesulfonyl) imide and lithium bis (fluorosulfonyl) imide, the fluoroether flame retardant is methyl nonafluorobutyl ether, and the prepared electrolyte is lithium bis (trifluoromethanesulfonyl) imide/lithium bis (fluorosulfonyl) imide/ethylene glycol dimethyl ether/methyl nonafluorobutyl ether (the molar ratio is 0.5:0.5:2:2).
Example 4
Preparing a non-combustible ether electrolyte, which comprises the following components: the solvent is ethylene glycol dimethyl ether, the electrolyte salt is lithium bis (fluorosulfonyl) imide, the fluoroether flame retardant is 1,2, 3,4, 5-decafluoro-3-methoxy-4- (trifluoromethyl) pentane, the prepared electrolyte is lithium bis (fluorosulfonyl) imide/ethylene glycol dimethyl ether/1, 2,3,4, 5-decafluoro-3-methoxy-4- (trifluoromethyl) pentane (molar ratio is 1:2:2).
Example 5
The high-concentration ether electrolyte is prepared and comprises the following components: the solvent is ethylene glycol dimethyl ether, the electrolyte salt is bis (pentafluoroethylsulfonyl) iminolithium and lithium difluorosulfonyl imide, and the prepared electrolyte is bis (pentafluoroethylsulfonyl) iminolithium/lithium difluorosulfonyl imide/ethylene glycol dimethyl ether (the molar ratio is 1:0.25:2).
Example 6
Preparing a non-combustible ether electrolyte, which comprises the following components: the solvent is ethylene glycol dimethyl ether, the electrolyte salt is bis (pentafluoroethylsulfonyl) iminolithium and lithium difluorosulfonyl imide, the fluoroether diluent is 1,2, 3,4, 5-decafluoro-3-methoxy-4- (trifluoromethyl) pentane, the prepared electrolyte is bis (pentafluoroethylsulfonyl) iminolithium/bis (fluorosulfonyl) iminolithium/ethylene glycol dimethyl ether/1, 2,3,4, 5-decafluoro-3-methoxy-4- (trifluoromethyl) pentane (molar ratio of 1:0.25:2:2).
Examples 2 and 3 are respectively non-combustible ether electrolyte solutions containing different salt ratios, and the optical photographs are shown in fig. 1. The results show that the non-combustible ether electrolyte of example 2 containing only lithium difluorosulfimide salt showed significant phase separation, whereas the non-combustible ether electrolyte of double salt formulation of example 3 showed no phase separation.
Examples 4 and 6 are respectively non-combustible ether electrolyte solutions containing different salt ratios, and the optical photographs are shown in fig. 2. The results show that the non-combustible ether electrolyte of example 4 containing only lithium difluorosulfimide salt showed significant phase separation, whereas the non-combustible ether electrolyte of double salt formulation of example 6 did not show phase separation.
The conventional carbonate electrolyte, the high-concentration ether electrolyte, and the non-combustible ether electrolyte, which were respectively prepared in example 1, example 5, and example 6, were subjected to an ignition test, and the test results are shown in fig. 3. The results show that the conventional electrolytes and the high-concentration ether electrolytes in examples 1 and 5 are highly flammable, while the non-flammable ether electrolyte in example 6 is non-flammable.
The conventional carbonate electrolyte and the non-fuel ether electrolyte prepared in example 1 and example 6 were prepared into Li/Cu half batteries using a copper foil as a positive electrode and a lithium foil as a negative electrode, respectively, and Li/Cu cycle experiments were performed. The results of the charge and discharge program test are shown in fig. 4. The results show that half cells using the non-combustible ether electrolyte of example 6 have higher coulombic efficiencies than half cells using the conventional carbonate electrolyte of example 1.
The conventional carbonate-based electrolyte and the non-combustible ether-based electrolyte prepared in example 1 and example 6 were prepared into Li/Cu half batteries with a copper foil as a positive electrode and a lithium foil as a negative electrode, respectively, and 10 Li/Cu cycle experiments were performed. The front and cross-sections of the recycled copper foil were characterized for morphology and the results are shown in fig. 5. The results show that the surface of the copper foil using the non-combustible ether electrolyte prepared in example 6 was very flat and large in size, but the surface of the copper foil after being circulated using the conventional carbonate electrolyte prepared in example 1 exhibited long-chain lithium dendrites. In addition, the thickness of lithium deposited on the copper foil using the nonflammable ether electrolyte prepared in example 6 was much smaller than that of the conventional carbonate electrolyte.
The conventional carbonate-based electrolyte and the non-combustible ether-based electrolyte prepared in example 1 and example 6 were prepared into lithium metal batteries using LiNi 0.8Mn0.1Co0.1O2 as a positive electrode and lithium foil as a negative electrode, respectively, and the cycle performance was tested by a charge-discharge procedure, and the results are shown in fig. 6. The results show that the lithium metal battery adopting the non-combustible ether electrolyte prepared in the example 6 has better cycle stability.
The conventional carbonate-based electrolyte and the non-combustible ether-based electrolyte prepared in example 1 and example 6 were prepared into lithium metal batteries using LiNi 0.8Mn0.1Co0.1O2 as a positive electrode and lithium foil as a negative electrode, respectively, and the rate performance was tested by a charge-discharge procedure, and the results are shown in fig. 7. The results show that the lithium metal battery adopting the non-combustible ether electrolyte prepared in the example 6 has better rate performance.
The LiNi 0.8Mn0.1Co0.1O2 positive electrode was charged to 4.4V, and the charged positive electrode material was mixed with the electrolyte prepared in example 1 and example 6 at a mass ratio of (2:5), and was charged into a high-pressure crucible to perform differential scanning micro thermal test, and the result is shown in fig. 8. The results show that the non-combustible ether electrolyte of example 6 was higher in initial/peak temperature at which thermal runaway occurred after mixing with the charged positive electrode than the conventional electrolyte of example 1, and that the non-combustible ether electrolyte of example 6 was smaller in heat at which thermal runaway occurred with the charged positive electrode than the conventional electrolyte of example 1.
The foregoing description of the embodiments has been provided for the purpose of illustrating the general principles of the invention, and is not meant to limit the invention thereto, but to limit the invention thereto, and any modifications, equivalents, improvements and equivalents thereof may be made without departing from the spirit and principles of the invention.

Claims (8)

1.A non-combustible electrolyte for a lithium metal battery, the non-combustible electrolyte comprising a solvent, an electrolyte salt, and a fluoroether flame retardant, wherein:
The solvent comprises at least one of an ether solvent, an ester solvent and a sulfone solvent;
the fluoroether flame retardant comprises fluoroether with F/H molar ratio more than or equal to 3;
The electrolyte salt comprises at least two of lithium bis (trifluoromethanesulfonyl) imide, lithium bis (pentafluoroethylsulfonyl) imide, lithium bis (heptafluoropropylsulfonyl) imide and lithium bis (nonafluorobutylsulfonyl) imide, and the mole percentage of the carbon-fluorine chain-containing salt in the electrolyte salt is not less than 50%; the hydrogen bonding effect between the fluoroether flame retardant/anion/solvent in the electrolyte is balanced by adjusting the composition of the added electrolyte salt and controlling the adding proportion of different anion electrolyte salts, so that the problem of electrolyte phase separation caused by adding fluoroether with high F/H molar ratio is solved.
2. The non-combustible electrolyte of claim 1 wherein: the ether solvent comprises at least one of ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, tetrahydrofuran and 1, 3-dioxane.
3. The non-combustible electrolyte of claim 1 wherein: the ester solvent comprises at least one of methyl ethyl carbonate, ethylene carbonate, propylene carbonate, butylene carbonate, vinylene carbonate, dimethyl carbonate, diethyl carbonate and gamma-butyrolactone.
4. The non-combustible electrolyte of claim 1 wherein: the sulfone solvent comprises at least one of sulfolane, dimethyl sulfone and dimethyl sulfoxide.
5. The non-combustible electrolyte of claim 1 wherein: the fluoroether flame retardant is at least one of methyl nonafluorobutyl ether, 2- (trifluoromethyl) -3-ethoxy-1,1,1,2,3,4,4,5,5,6,6,6-dodecafluoro-2- (trifluoromethyl) -hexane and 1,2,3,4, 5-decafluoro-3-methoxy-4- (trifluoromethyl) pentane.
6. The non-combustible electrolyte of claim 1 wherein: in the electrolyte, the mol ratio of the solvent to the fluoroether flame retardant is 1:0.1-10.
7. The non-combustible electrolyte of claim 1 wherein: in the electrolyte, the molar ratio of the electrolyte salt to the solvent is 1:0.5-10.
8. A lithium metal battery characterized in that: use of the non-combustible electrolyte of any one of claims 1-7.
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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103401020A (en) * 2013-08-08 2013-11-20 东莞市杉杉电池材料有限公司 High-voltage lithium ion battery electrolyte
KR20170127723A (en) * 2016-05-12 2017-11-22 삼성에스디아이 주식회사 Lithium metal battery
CN109860712A (en) * 2019-03-29 2019-06-07 山东海容电源材料股份有限公司 A kind of fire-retardant nonaqueous electrolytic solution of high safety
CN110061291A (en) * 2019-03-26 2019-07-26 天津市捷威动力工业有限公司 A kind of high-temperature stable electrolyte and its lithium ion battery
JP2020061206A (en) * 2018-10-05 2020-04-16 国立大学法人山口大学 Electrolyte for incombustible or self-extinguishing lithium ion battery and lithium ion battery
CN113113670A (en) * 2021-04-09 2021-07-13 浙江大学山东工业技术研究院 Non-combustible lithium metal battery electrolyte and preparation method thereof, lithium metal battery and preparation method thereof

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10224571B2 (en) * 2016-09-01 2019-03-05 GM Global Technology Operations LLC Fluorinated ether as electrolyte co-solvent for lithium metal based anode
WO2020088436A1 (en) * 2018-10-29 2020-05-07 上海紫剑化工科技有限公司 Electrolyte, additive thereof, secondary cell, and application thereof

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103401020A (en) * 2013-08-08 2013-11-20 东莞市杉杉电池材料有限公司 High-voltage lithium ion battery electrolyte
KR20170127723A (en) * 2016-05-12 2017-11-22 삼성에스디아이 주식회사 Lithium metal battery
JP2020061206A (en) * 2018-10-05 2020-04-16 国立大学法人山口大学 Electrolyte for incombustible or self-extinguishing lithium ion battery and lithium ion battery
CN110061291A (en) * 2019-03-26 2019-07-26 天津市捷威动力工业有限公司 A kind of high-temperature stable electrolyte and its lithium ion battery
CN109860712A (en) * 2019-03-29 2019-06-07 山东海容电源材料股份有限公司 A kind of fire-retardant nonaqueous electrolytic solution of high safety
CN113113670A (en) * 2021-04-09 2021-07-13 浙江大学山东工业技术研究院 Non-combustible lithium metal battery electrolyte and preparation method thereof, lithium metal battery and preparation method thereof

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
锂金属电池电解液组分调控的研究进展;冯建文;胡时光;韩兵;肖映林;邓永红;王朝阳;;储能科学与技术;20201030(06);全文 *

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