CN114464890A - 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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CN114464890A
CN114464890A CN202210167022.1A CN202210167022A CN114464890A CN 114464890 A CN114464890 A CN 114464890A CN 202210167022 A CN202210167022 A CN 202210167022A CN 114464890 A CN114464890 A CN 114464890A
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electrolyte
solvent
ether
imide
lithium
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CN114464890B (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
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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
    • H01M10/052—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
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Abstract

The invention discloses a non-combustible electrolyte and a lithium metal battery based on the non-combustible electrolyte, wherein the non-combustible electrolyte comprises a solvent, electrolyte salt and a fluoroether flame retardant, the solvent comprises at least one of ether solvent, ester solvent and sulfone solvent, the electrolyte salt comprises at least two lithium salts containing different anions, and the fluoroether flame retardant comprises fluoroether with the F/H molar ratio not less than 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 cycle 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 higher energy densities than lithium ion batteries, and thus have received much attention from researchers in academia and industry. The lithium metal as a negative electrode has ultrahigh theoretical specific capacity (3860mAh g)-1) And an ultra-low electrochemical redox potential (-3.04V vs. standard hydrogen electrode). However, the safety and stability issues of lithium metal batteries remain a significant challenge for their commercial applications. Most of the currently available electrolytes are highly flammable, and overcharging, short-circuiting 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 in a lithium-removed state4+Ions, which may undergo severe side reactions with the electrolyte at high pressure, will further exacerbate the thermal runaway reaction of the battery.
The addition of a phosphate ester solvent (e.g., trimethyl phosphate) having flame retardancy to the electrolyte is expected to solve the safety problem of the lithium metal battery. However, all of these phosphate solvents have high intrinsic reactivity with lithium metal, which results in poor stability of the lithium metal battery. The stability of the lithium metal battery can be improved to some extent by limiting the number of free solvent molecules using a high concentration of phosphate ester electrolyte. However, due to the inherent high reactivity 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, the common ether molecules are highly flammable, and suppressing the free ether molecules by preparing a high concentration of electrolyte only reduces the flammability to a limited extent. In order to reduce the inherent flammability of ether molecules, it is an effective method to replace the active hydrogen atoms in ether molecules with fluorine atoms. Such as bis (2,2, 2-trifluoroethyl) ether (F/H molar ratio 1.5, flash point 1 ℃) and 1,1,2, 2-tetrafluoroethyl-2, 2,3, 3-tetrafluoropropyl ether (F/H molar ratio 2, flash point 27.5 ℃) have been successfully added to high concentration electrolytes. These fluoroethers hardly participate in Li due to the electron-withdrawing effect of fluorine atoms+Solvating and thus not destroying its high salt/solvent ratio solvated structure, thereby successfully preserving high concentration electrolyte electrochemical performance. However, the F/H molar ratio and the flash point of the fluorinated ethers reported at present are lower, and the flammability is still higher. In order 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 again causes phase separation of the electrolyte. Therefore, how to add the fluoroether with high F/H molar ratio into the electrolyte without causing phase separation of the electrolyte is a critical problem to be solved at present.
Disclosure of Invention
In view of the above, the present invention provides a non-combustible electrolyte and a lithium metal battery based on the same, so as to improve the safety of the electrolyte and enable the lithium metal battery based on the same to have excellent performance.
In order to solve the technical problem, the invention adopts the following technical scheme:
the invention firstly provides a non-combustible electrolyte, which comprises 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 electrolyte salt includes at least two of lithium salts containing different anions; the fluoroether flame retardant comprises fluoroether with the F/H molar ratio being 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 (fluorosulfonyl) imide, 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 of 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 of 3) and 1,1,1,2,2,3,4,5, 5-decafluoro-3-methoxy-4- (trifluoromethyl) pentane (F/H molar ratio of 4.33).
Furthermore, in the electrolyte, the molar ratio of the solvent to the fluoroether flame retardant is 1: 0.1-10, and the molar ratio of the electrolyte salt to the solvent is 1: 0.5-10.
Furthermore, while the electrochemical performance of the electrolyte is considered, the hydrogen bond effect between the fluoroether flame retardant/anion/solvent in the electrolyte is balanced by regulating and controlling the proportion of the electrolyte salt, so as to solve the phase separation problem of the electrolyte, wherein the electrolyte salt has various proportion schemes, wherein the molar percentage of the carbon-fluorine chain-containing salt is not less than 50%, for example: the electrolyte salt can be prepared by compounding lithium bis (pentafluoroethylsulfonyl) imide and lithium bis (fluorosulfonyl) imide according to the molar ratio of 1: 0.1-1; the electrolyte salt can be prepared by compounding lithium bis (pentafluoroethylsulfonyl) imide and lithium bis (trifluoromethanesulfonyl) imide according to the molar ratio of 1: 0.1-1; the electrolyte salt can be prepared by compounding lithium bis (trifluoromethanesulfonyl) imide and lithium bis (fluorosulfonyl) imide according to the molar ratio of 1: 0.1-1; the electrolyte salt can be prepared by compounding lithium bis (heptafluoropropylsulfonyl) imide and lithium bis (fluorosulfonyl) imide according to the molar ratio of 1: 0.1-1; the electrolyte salt can be prepared by compounding lithium bis (nonafluorobutylsulfonyl) imide and lithium bis (fluorosulfonyl) imide according to the molar 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 fire retardant in the nonflammable electrolyte has high F/H molar ratio and high flash point due to the molecular structure characteristics, so that the safety performance of the electrolyte is greatly improved. Meanwhile, due to the low dielectric constant of the fluoroether flame retardant, the viscosity of the electrolyte is reduced, and the wettability of the electrolyte is improved.
2. The electrolyte salt in the non-combustible electrolyte provided by the invention balances the hydrogen bond effect between the fluoroether flame retardant/anion/solvent in the electrolyte by adjusting the composition of the added electrolyte salt and controlling the addition proportion of different anion electrolyte salts while considering the electrochemical performance of the electrolyte, and solves the problem of phase separation of the electrolyte caused by adding the fluoroether with high F/H molar ratio.
3. The lithium metal battery adopting the non-combustible electrolyte provided by the invention can realize the dendrite-free deposition growth and high coulombic efficiency of the lithium metal cathode and the 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 removal anode and the electrolyte in thermal runaway are obviously improved compared with the traditional ester electrolyte by adopting the electrolyte, and the performance of the lithium metal battery is obviously improved.
Drawings
FIG. 1 is a comparative photo-photograph of the electrolytes obtained in example 2 and example 3;
FIG. 2 is a comparative photo-photograph of the electrolytes obtained in examples 4 and 6;
FIG. 3 is a comparative graph of the ignition test of the electrolytes obtained in examples 1, 5 and 6;
fig. 4 is a graph comparing the coulombic efficiencies of the lithium metal negative electrodes of the conventional electrolyte of example 1 and the non-ether electrolyte of example 6;
FIG. 5 is a graph comparing the topography of the copper foil surface after cycling (first column) and the thickness of lithium deposited on the copper foil surface (second column) for Li/Cu half cells of the conventional electrolyte in example 1 and the non-ether electrolyte in example 6;
fig. 6 is a graph comparing cycle performance of a lithium metal battery assembled with a conventional electrolyte of example 1 and a non-ether electrolyte of example 6;
fig. 7 is a graph comparing rate performance of a lithium metal battery assembled with a conventional electrolyte of example 1 and a non-fuel ether electrolyte of example 6;
fig. 8 is a differential scanning calorimetry experiment comparison of the conventional electrolyte in example 1 and the non-ether electrolyte in example 6 mixed with a delithiated positive electrode.
Detailed Description
In order that the objects, technical solutions and advantages of the present invention will become more apparent, the present invention will be further described in detail with reference to the accompanying drawings in conjunction with the following specific embodiments.
The invention provides a non-combustible electrolyte, which comprises a solvent, 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 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 (fluorosulfonyl) imide, 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 of 3), 2- (trifluoromethyl) -3-ethoxy-1, 1,1,2,3,4,4,5,5,6,6, 6-dodecafluoro-2- (trifluoromethyl) -hexane and 1,1,1,2,2,3,4,5,5, 5-decafluoro-3-methoxy-4- (trifluoromethyl) pentane (F/H molar ratio of 4.33).
According to the embodiment of the invention, the electrochemical performance of the electrolyte is considered, and the hydrogen bond effect between the fluoroether flame retardant/anion/solvent in the electrolyte is balanced by regulating and controlling the proportion of the electrolyte salt, so that the phase separation problem of the electrolyte is solved, wherein the electrolyte salt has a plurality of proportion schemes, the mole percentage of the carbon-fluorine chain-containing salt is not less than 50%, and the feasible partial schemes comprise: the lithium bis (pentafluoroethylsulfonyl) imide and the lithium bis (fluorosulfonyl) imide can be compounded into an electrolyte salt according to a molar ratio of 1: 0.1-1, such as 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 prepared by compounding lithium bis (pentafluoroethylsulfonyl) imide and lithium bis (trifluoromethanesulfonyl) imide according to the molar ratio of 1: 0.1-1, such as 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 prepared by compounding lithium bis (trifluoromethanesulfonyl) imide and lithium bis (fluorosulfonyl) imide according to the molar ratio of 1: 0.1-1, such as 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 prepared by compounding lithium bis (heptafluoropropylsulfonyl) imide and lithium bis (fluorosulfonyl) imide according to the molar ratio of 1: 0.1-1, such as 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 prepared by compounding lithium bis (nonafluorobutylsulfonyl) imide and lithium bis (fluorosulfonyl) imide according to the molar ratio of 1: 0.1-1, such as 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 the embodiment of the invention, the molar ratio of the solvent to the fluoroether flame retardant in the electrolyte is 1: 0.1-10, such as: 1: 0.1; 1: 0.5; 1: 1; 1: 2; 1: 5; 1:10.
According to the embodiment of the invention, the molar ratio of the electrolyte salt to the solvent in the electrolyte is 1: 0.5-10, such as: 1: 0.5; 1: 1; 1: 2; 1: 5; 1:10.
The fluoroether fire retardant in the nonflammable electrolyte has high F/H molar ratio and high flash point due to the molecular structure characteristics, so that the safety performance of the electrolyte is greatly improved. Meanwhile, due to the low dielectric constant of the fluoroether flame retardant, the viscosity of the electrolyte is reduced, a local high-concentration solvation structure is formed, and the wettability of the electrolyte is improved. The electrolyte salt in the nonflammable electrolyte solves the problem of electrolyte phase separation caused by adding the fluoroether with high F/H molar ratio by adjusting the composition of the added electrolyte salt and controlling the addition proportion of different anion electrolyte salts.
The technical effects of the invention are further illustrated by the following specific examples and test characterization thereof.
Example 1
Preparing a traditional carbonate electrolyte, which comprises the following components: the solvent is ethylene carbonate and ethyl methyl carbonate, the electrolyte salt is lithium hexafluorophosphate, the additive is vinylene carbonate, and the prepared electrolyte is prepared by dissolving lithium hexafluorophosphate (1.0mol/L) in vinylene carbonate/ethyl methyl carbonate (the mass ratio is 3:7) and vinylene carbonate with the mass fraction of 2%.
Example 2
Preparing non-flammable 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 (molar ratio is 1:2: 2).
Example 3
Preparing non-flammable ether electrolyte, which comprises the following components: the solvent is ethylene glycol dimethyl ether, the electrolyte salt is bis (trifluoromethanesulfonyl) imide lithium and lithium difluorosulfonimide, the fluoroether flame retardant is methyl nonafluorobutyl ether, and the prepared electrolyte is bis (trifluoromethanesulfonyl) imide lithium/lithium difluorosulfonimide/ethylene glycol dimethyl ether/methyl nonafluorobutyl ether (the molar ratio is 0.5:0.5:2: 2).
Example 4
Preparing non-flammable ether electrolyte, which comprises the following components: the solvent is ethylene glycol dimethyl ether, the electrolyte salt is lithium bis-fluorosulfonylimide, the fluoroether flame retardant is 1,1,1,2,2,3,4,5,5, 5-decafluoro-3-methoxy-4- (trifluoromethyl) pentane, and the prepared electrolyte is lithium bis-fluorosulfonylimide/ethylene glycol dimethyl ether/1, 1,1,2,2,3,4,5,5, 5-decafluoro-3-methoxy-4- (trifluoromethyl) pentane (the molar ratio is 1:2: 2).
Example 5
Preparing high-concentration ether electrolyte, which comprises the following components: the solvent is ethylene glycol dimethyl ether, the electrolyte salt is bis (pentafluoroethylsulfonyl) lithium imide and lithium bis (fluorosulfonyl) imide, and the prepared electrolyte is bis (pentafluoroethylsulfonyl) lithium imide/lithium bis (fluorosulfonyl) imide/ethylene glycol dimethyl ether (the molar ratio is 1:0.25: 2).
Example 6
Preparing non-flammable ether electrolyte, which comprises the following components: the solvent is ethylene glycol dimethyl ether, the electrolyte salt is bis (pentafluoroethylsulfonyl) imino lithium and bis (fluorosulfonyl) imide lithium, the fluoroether diluent is 1,1,1,2,2,3,4,5,5, 5-decafluoro-3-methoxy-4- (trifluoromethyl) pentane, and the prepared electrolyte is bis (pentafluoroethylsulfonyl) imino lithium/bis (fluorosulfonyl) imide lithium/ethylene glycol dimethyl ether/1, 1,1,2,2,3,4,5,5, 5-decafluoro-3-methoxy-4- (trifluoromethyl) pentane (molar ratio is 1:0.25:2: 2).
Examples 2 and 3 are non-flammable ether electrolyte solutions containing different salt ratios, and their optical photographs are shown in fig. 1. The results show that the non-flammable ether electrolyte containing only lithium bis (fluorosulfonyl) imide salt in example 2 showed significant phase separation, while the non-flammable ether electrolyte containing the bis-salt formulation in example 3 showed no phase separation.
Examples 4 and 6 are non-flammable ether electrolyte solutions containing different salt ratios, and their optical photographs are shown in fig. 2. The results show that the non-flammable ether-based electrolyte containing only lithium bis (fluorosulfonyl) imide salt in example 4 showed significant phase separation, while the non-flammable ether-based electrolyte containing the bis-salt formulation in example 6 showed no phase separation.
The conventional carbonate electrolyte, the high-concentration ether electrolyte, and the non-flammable ether electrolyte, which were prepared in examples 1, 5, and 6, respectively, were subjected to an ignition test, and the test results are shown in fig. 3. The results showed that the conventional electrolytes and the high-concentration ether-based electrolytes in examples 1 and 5 were highly flammable, whereas the non-flammable ether-based electrolyte in example 6 was non-flammable.
The conventional carbonate electrolyte and the non-flammable ether electrolyte prepared in examples 1 and 6 were used to prepare Li/Cu half cells with a copper foil as a positive electrode and a lithium foil as a negative electrode, respectively, and a Li/Cu cycle experiment was performed. The results of the charge and discharge procedure test are shown in fig. 4. The results show that the half-cell using the non-ether electrolyte formulated in example 6 has higher coulombic efficiency than the half-cell using the conventional carbonate electrolyte formulated in example 1.
The conventional carbonate electrolyte and the non-flammable ether electrolyte prepared in examples 1 and 6 were used to prepare Li/Cu half cells with copper foil as the positive electrode and lithium foil as the negative electrode, respectively, and Li/Cu cycle experiments were performed for 10 times. The front and cross-section of the recycled copper foil were characterized in morphology, with the results shown in fig. 5. The results show that the lithium deposited on the surface of the copper foil using the non-ether electrolyte configured in example 6 is very flat and large in size, but the surface of the copper foil after the circulation using the conventional carbonate electrolyte configured in example 1 shows long-strip lithium dendrites. In addition, the thickness of lithium deposited on the copper foil using the non-ether electrolyte configured in example 6 was much smaller than that of the conventional carbonate electrolyte.
The conventional carbonate electrolytes and non-flammable ether electrolytes prepared in examples 1 and 6 were mixed with LiNi0.8Mn0.1Co0.1O2Lithium metal batteries were fabricated with the positive electrode and the lithium foil as the negative electrode, respectively, and their cycle performance was measured by a charge-discharge procedure, and the results are shown in fig. 6. The results show that the lithium metal battery using the non-ether electrolyte configured in example 6 has better cycle stability.
The conventional carbonate electrolytes and non-flammable ether electrolytes prepared in examples 1 and 6 were mixed with LiNi0.8Mn0.1Co0.1O2Lithium metal batteries were fabricated with the positive electrode and the lithium foil as the negative electrode, respectively, and the rate performance was measured by a charge-discharge procedure, and the results are shown in fig. 7. The results show that the lithium metal battery using the non-ether electrolyte prepared in example 6 has better rate capability.
Reacting LiNi0.8Mn0.1Co0.1O2The positive electrode was charged to 4.4V, and the charged positive electrode material and the electrolytes prepared in examples 1 and 6 were mixed at a mass ratio of (2:5), respectively, and the mixture was put into a high-pressure crucible to perform differential scanning microcalorimetry, and the results are shown in fig. 8. The results showed that the non-combustible ether electrolyte of example 6 had a higher initial/peak temperature at which thermal runaway occurred when mixed with the charged positive electrode than the conventional electrolyte of example 1, and that the non-combustible ether electrolyte of example 6 had a smaller amount of heat evolved from thermal runaway with the charged positive electrode than the conventional electrolyte of example 1.
The above-mentioned embodiments are intended to illustrate the objects, technical solutions and advantages of the present invention in further detail, and it should be understood that the above-mentioned embodiments are only exemplary embodiments of the present invention and are not intended to limit the present invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (9)

1. A non-flammable 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 electrolyte salt includes at least two of lithium salts containing different anions;
the fluoroether flame retardant comprises fluoroether with the F/H molar ratio more than or equal to 3.
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 electrolyte salt includes at least two of lithium bis (fluorosulfonyl) imide, lithium bis (trifluoromethanesulfonyl) imide, lithium bis (pentafluoroethylsulfonyl) imide, lithium bis (heptafluoropropylsulfonyl) imide, and lithium bis (nonafluorobutylsulfonyl) imide.
6. 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 1,1,1,2,2,3,4,5,5, 5-decafluoro-3-methoxy-4- (trifluoromethyl) pentane.
7. The non-combustible electrolyte of claim 1 wherein: in the electrolyte, the molar ratio of the solvent to the fluoroether flame retardant is 1: 0.1-10.
8. 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.
9. A lithium metal battery, characterized in that: use of a non-combustible electrolyte as claimed in any of claims 1 to 8.
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Citations (8)

* 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
US20180062206A1 (en) * 2016-09-01 2018-03-01 GM Global Technology Operations LLC Fluorinated ether as electrolyte co-solvent for lithium metal based anode
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
US20210399341A1 (en) * 2018-10-29 2021-12-23 Shanghai Zijian Chemical Technology Co., Ltd Electrolyte, Additive Thereof, Secondary Cell, And Application Thereof

Patent Citations (8)

* 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
US20180062206A1 (en) * 2016-09-01 2018-03-01 GM Global Technology Operations LLC Fluorinated ether as electrolyte co-solvent for lithium metal based anode
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
US20210399341A1 (en) * 2018-10-29 2021-12-23 Shanghai Zijian Chemical Technology Co., Ltd Electrolyte, Additive Thereof, Secondary Cell, And Application Thereof
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
冯建文;胡时光;韩兵;肖映林;邓永红;王朝阳;: "锂金属电池电解液组分调控的研究进展", 储能科学与技术, no. 06, 30 October 2020 (2020-10-30) *

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