Electrolyte composition, secondary battery, battery module, battery pack, and power consumption device

Abstract

The present application provides an electrolyte composition, a secondary battery, a battery module, a battery pack, and a power consumption device. The electrolyte composition is a non-Newtonian fluid electrolyte composition. When subjected to a certain external force, mechanical thixotropy occurs, thereby improving the impact resistance and safety of the battery.

Description

[Technical Field]

[0001] The present application relates to the technical field of secondary batteries, and in particular to electrolyte compositions, secondary batteries, battery modules, battery packs, and power consuming devices. [Background technology]

[0002] In recent years, secondary batteries have been widely applied in energy storage power supply systems such as hydroelectric, thermal, wind and solar power plants, as well as in many fields such as power tools, electric bicycles, electric motorcycles, electric vehicles, military equipment, aerospace, etc. As the use of secondary batteries becomes more widespread, higher requirements are being placed on their performance and safety.

[0003] Currently, liquid electrolytes and all-solid-state electrolytes are the two types of electrolytes commonly used in batteries. However, liquid electrolytes are prone to forming dendrites on the negative electrode during cycling, making the battery prone to short circuits and causing safety issues. Meanwhile, all-solid-state electrolytes are difficult to form good interfacial contact with the electrodes. Neither of these can meet the application needs of new generation electrochemical systems. Summary of the Invention

[0004] The present application has been made in view of the above-mentioned problems, and aims to provide an electrolyte composition that can generate mechanical thixotropy when subjected to a certain external force, thereby improving the impact resistance and safety of a battery.

[0005] A first aspect of the present application provides an electrolyte composition that is a non-Newtonian fluid electrolyte composition.

[0006] Non-Newtonian fluid electrolyte compositions can undergo mechanical thixotropy, i.e., change from a flowable state to a solid state, under the action of a certain external force, thereby effectively improving the short-circuit prevention safety and impact resistance of batteries. Furthermore, compared with other quasi-solid electrolytes and liquid electrolytes, non-Newtonian fluid electrolyte compositions can achieve the lowest electrolyte ohmic resistance and interfacial resistance at low stacking pressures, improving the battery assembly process.

[0007] After stirring the electrolyte composition for 10 seconds at 25°C with a 62# or 64# rotor of a Dveslvtjo rotational viscosity tester at a speed of 12 rpm, the viscosity of the electrolyte composition is 1000 mPa·s to 50000 mPa·s.

[0008] The non-Newtonian fluid electrolyte composition has a high viscosity, which can effectively suppress gas generation in the battery and further improve the cycle performance of the battery compared to batteries using liquid electrolytes of similar composition.

[0009] In any embodiment, after stirring the electrolyte composition for 10 minutes while rotating at 25°C with a 62# or 64# rotor in a Dveslvtjo rotational viscosity tester at a speed of 12 revolutions per minute, the viscosity of the electrolyte composition increases by more than 100 mPa·s compared to the viscosity after 10 seconds of testing under the same conditions.

[0010] Non-Newtonian fluid electrolyte compositions fail to satisfy Newton's law of viscosity, i.e., shear stress and shear strain rate have a non-linear relationship. Non-Newtonian fluid electrolyte compositions herein are shear-thickening liquids, whose viscosity increases with increasing shear rate or shear time.

[0011] In any embodiment, the non-Newtonian fluid electrolyte composition has a loss factor after mechanical thixotropy that drops by more than 10% relative to the loss factor before mechanical thixotropy.

[0012] Non-Newtonian fluid electrolytes have mechanical thixotropy properties. When subjected to external impact such as nail penetration or pressure, the non-Newtonian fluid electrolyte composition changes from a flowable state to a solid state, and the phase change causes a decrease in its loss factor. The decrease in the loss factor of the non-Newtonian fluid electrolyte composition is more than 10%, i.e., the storage modulus is significantly increased, thereby effectively improving the safety and impact resistance of the battery in the event of an accident such as nail penetration.

[0013] In any embodiment, the non-Newtonian fluid electrolyte composition comprises one of an organic solvent and an ionic liquid, an electrolyte salt, and suspended particles.

[0014] A non-Newtonian fluid electrolyte composition comprising an electrolyte salt, an ionic liquid, and suspended particles, or a non-Newtonian fluid electrolyte composition comprising an electrolyte salt, an organic solvent, and suspended particles, has excellent safety and impact resistance, and at the same time, can achieve the lowest electrolyte ohmic resistance and interfacial resistance at low stacking pressure, and the battery assembly process is simpler.

[0015] In any embodiment, the non-Newtonian fluid electrolyte composition further comprises a polymer.

[0016] The introduction of polyethylene oxide into the non-Newtonian fluid electrolyte composition contributes to improving the cycle performance of the battery, lowering the battery swelling rate, reducing the gas generation rate, and improving the safety of the battery.

[0017] In any embodiment, the electrolyte salt comprises a sodium salt, the sodium salt comprising one or more of sodium chloride, sodium bromide, sodium nitrate, sodium perchlorate, sodium hexafluorophosphate, sodium acetate, sodium trifluoroacetate, sodium trifluoromethanesulfonate, sodium bis(fluorosulfonyl)imide, sodium bis(trifluoromethanesulfonyl)imide, optionally one or more of sodium trifluoromethanesulfonate, sodium bis(fluorosulfonyl)imide, sodium bis(trifluoromethanesulfonyl)imide.

[0018] The sodium salt enhances the safety and impact resistance of the non-Newtonian fluid electrolyte composition, enhances the cycle performance of the battery, and reduces the gas generation rate of the battery and the stacking pressure at which the ohmic resistance and interfacial resistance of the electrolyte are minimized, thereby contributing to enhancing battery safety and improving the battery assembly process. Selectively controlling the sodium salt to include one or more of sodium trifluoromethanesulfonate, sodium bis(fluorosulfonyl)imide, and sodium bis(trifluoromethanesulfonyl)imide contributes to further enhancing the cycle performance of the battery.

[0019] In any embodiment, the organic solvent comprises one or more of an ether organic solvent, an ester organic solvent, a sulfur-containing organic solvent, including one or more of ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, ethylene carbonate, propylene carbonate, butylene carbonate, vinylene carbonate, fluoroethylene carbonate, ethyl methyl carbonate, dimethyl carbonate, diethyl carbonate, dipropyl carbonate, dimethyl sulfoxide, and optionally ethylene glycol dimethyl ether.

[0020] The organic solvent enhances the safety and impact resistance of the non-Newtonian fluid electrolyte composition, reduces the stacking pressure of the battery when the ohmic resistance and interfacial resistance of the electrolyte are minimized, and contributes to improving the battery assembly process. Selectively controlling the organic solvent to contain ethylene glycol dimethyl ether further enhances the safety and impact resistance of the non-Newtonian fluid electrolyte composition, improves the cycle performance of the battery to a greater extent, and significantly reduces the gas generation rate of the battery, contributing to improving the safety of the battery.

[0021] In any embodiment, the ionic liquid comprises one or more of 1-butyl-3-methylimidazolium chloride, 1-alkyl-3-methylimidazolium tetrafluoroborate, N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide, 5-azoniaspiro[4,4]nonane hexafluorophosphate, trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide, tetrabutylphosphonium hexafluorophosphate, and optionally one or more of N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide, trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide.

[0022] The ionic liquid enhances the safety and impact resistance of the non-Newtonian fluid electrolyte composition, reduces the stacking pressure of the battery when the ohmic resistance and interfacial resistance of the electrolyte are minimized, and contributes to improving the battery assembly process. By selectively controlling the ionic liquid to include one or more of N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide and trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide, the safety and impact resistance of the non-Newtonian fluid electrolyte composition can be further enhanced, the cycle performance of the battery can be improved to a greater extent, and the gas generation rate of the battery and the stacking pressure when the ohmic resistance and interfacial resistance of the electrolyte are minimized can be significantly reduced, thereby enhancing battery safety and improving the battery assembly process.

[0023] In any embodiment, the polymer comprises polyethylene oxide, polyethylene glycol, polyvinylpyrrolidone, polymethylmethacrylate, polyvinylidene fluoride, polyvinyl alcohol, polyacrylamide, and optionally one or more of polyethylene oxide, polyethylene glycol.

[0024] The polymer enhances the safety and impact resistance of the non-Newtonian fluid electrolyte composition, and reduces the gas generation rate of the battery and the stacking pressure at which the ohmic resistance and interfacial resistance of the electrolyte are minimized, thereby improving battery safety and improving the battery assembly process. By selectively controlling the polymer to contain one or more of polyethylene oxide and polyethylene glycol, the cycle performance of the battery can be further improved, and the stacking pressure at which the ohmic resistance and interfacial resistance of the electrolyte are minimized can be significantly reduced, contributing to an improvement in the battery assembly process.

[0025] In any embodiment, the suspended particles include one or more of fumed silica, aluminum oxide, sodium oxide, lithium oxide, sodium fluoride, lithium fluoride, polyurethane, and optionally one or more of fumed silica, sodium oxide, and lithium oxide.

[0026] The suspended particles enhance the safety and impact resistance of the non-Newtonian fluid electrolyte composition, reduce the stacking pressure of the battery when the ohmic resistance and interfacial resistance of the electrolyte are minimized, and contribute to improving the battery assembly process. By selectively controlling the suspended particles to include one or more of fumed silica, sodium oxide, and lithium oxide, the cycle performance of the battery can be further improved, the gas generation rate of the battery can be significantly reduced, and the safety of the battery can be improved.

[0027] In any embodiment, the electrolyte salt comprises one or more of sodium trifluoromethanesulfonate, sodium bis(fluorosulfonyl)imide, and sodium bis(trifluoromethanesulfonyl)imide; the organic solvent comprises ethylene glycol dimethyl ether; the ionic liquid comprises one or more of N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide and trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide; the polymer comprises one or more of polyethylene oxide and polyethylene glycol; and the suspended particles comprise one or more of fumed silica, sodium oxide, and lithium oxide.

[0028] The selection of the electrolyte salt, organic solvent, ionic liquid, polymer and suspended particles contributes to improving the cycle performance of the battery.

[0029] In any embodiment, the electrolyte salt comprises one or more of sodium trifluoromethanesulfonate, sodium bis(fluorosulfonyl)imide, sodium bis(trifluoromethanesulfonyl)imide, the organic solvent comprises ethylene glycol dimethyl ether, and the suspended particles comprise one or more of fumed silica, sodium oxide, and lithium oxide.

[0030] The non-Newtonian fluid electrolyte composition comprising the above-mentioned electrolyte salt, organic solvent and suspended particles enhances the safety and impact resistance of the non-Newtonian fluid electrolyte composition, improves the cycle performance of the battery, and reduces the gas generation rate of the battery and the stacking pressure at which the ohmic resistance and interfacial resistance of the electrolyte are minimized, thereby contributing to improving the safety of the battery and the battery assembly process.

[0031] In any embodiment, the electrolyte salt comprises one or more of sodium trifluoromethanesulfonate, sodium bis(fluorosulfonyl)imide, sodium bis(trifluoromethanesulfonyl)imide, the organic solvent comprises ethylene glycol dimethyl ether, the polymer comprises one or more of polyethylene oxide, polyethylene glycol, and the suspended particles comprise one or more of fumed silica, sodium oxide, and lithium oxide.

[0032] The non-Newtonian fluid electrolyte composition comprising the above-mentioned electrolyte salt, organic solvent, polymer and suspended particles enhances the safety and impact resistance of the non-Newtonian fluid electrolyte composition, improves the cycle performance of the battery, and reduces the gas generation rate of the battery and the stacking pressure at which the ohmic resistance and interfacial resistance of the electrolyte are minimized, thereby contributing to improving the safety of the battery and the battery assembly process.

[0033] In any embodiment, the electrolyte salt comprises one or more of sodium trifluoromethanesulfonate, sodium bis(fluorosulfonyl)imide, sodium bis(trifluoromethanesulfonyl)imide, the ionic liquid comprises one or more of N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide, trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide, and the suspended particles comprise one or more of fumed silica, sodium oxide, and lithium oxide.

[0034] The non-Newtonian fluid electrolyte composition comprising the above-mentioned electrolyte salt, ionic liquid and suspended particles enhances the safety and impact resistance of the non-Newtonian fluid electrolyte composition, and reduces the stacking pressure of the battery when the ohmic resistance and interfacial resistance of the electrolyte are minimized, thereby contributing to an improvement in the battery assembly process.

[0035] In any embodiment, the electrolyte salt comprises one or more of sodium trifluoromethanesulfonate, sodium bis(fluorosulfonyl)imide, and sodium bis(trifluoromethanesulfonyl)imide; the ionic liquid comprises one or more of N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide and trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide; the polymer comprises one or more of polyethylene oxide and polyethylene glycol; and the suspended particles comprise one or more of fumed silica, sodium oxide, and lithium oxide.

[0036] The non-Newtonian fluid electrolyte composition comprising the above-mentioned electrolyte salt, ionic liquid, polymer and suspended particles enhances the safety and impact resistance of the non-Newtonian fluid electrolyte composition, reduces the stacking pressure of the battery when the ohmic resistance and interfacial resistance of the electrolyte are minimized, and contributes to improving the battery assembly process.

[0037] In any embodiment, based on the total mass of the non-Newtonian fluid electrolyte composition, the mass content of the electrolyte salt is 5% to 20%, the mass content of the organic solvent is 20% to 60%, the mass content of the ionic liquid is 20% to 60%, the mass content of the polymer is 0% to 40%, and the mass content of the suspended particles is greater than 0 and less than or equal to 20%.

[0038] By controlling the appropriate mass content of electrolyte salt, organic solvent, ionic liquid, polymer, and suspended particles, the safety and impact resistance of the non-Newtonian fluid electrolyte composition can be improved, the cycle performance of the battery can be enhanced, and the stacking pressure at which the gas generation rate of the battery and the ohmic resistance and interfacial resistance of the electrolyte are minimized can be reduced, thereby improving the safety of the battery and improving the battery assembly process.

[0039] In any embodiment, the non-Newtonian fluid electrolyte composition has a compressive strength of 35 kN to 200 kN.

[0040] The non-Newtonian fluid electrolyte composition has an appropriate compressive strength, which contributes to improving the impact resistance performance.

[0041] A second aspect of the present application provides a secondary battery comprising a positive electrode plate and the non-Newtonian fluid electrolyte composition described in any embodiment.

[0042] This secondary battery has excellent cycle performance.

[0043] In any embodiment, the secondary battery includes at least one of a lithium battery and a sodium battery.

[0044] In any embodiment, the secondary battery is a negative electrode-free sodium battery, which has a high energy density.

[0045] In any embodiment, the positive electrode plate includes a positive electrode active material, the positive electrode active material including at least one of a transition metal layered oxide, a polyanion compound, and a Prussian blue compound, and NaNi 1 / 3 Fe 1 / 3 Mn 1 / 3 O2, Na(Cu 1 / 9 Ni 2 / 9 Fe 1 / 3 Mn 1 / 3 )O2, Na 2 / 3 Ni 1 / 6 Mn 2 / 3 Cu 1 / 9 Mg 1 / 18 O2, Na4Fe3(PO4)2P2O7, NaFePO4, Na3V2(PO4)3, Na 1.9 CoFe(CN)6, Na2NiFe(CN)6, NaMnFe(CN)6.

[0046] Any of the above positive electrode active materials can provide the battery with excellent cycle performance and safety.

[0047] In any embodiment, a coating layer is provided on a surface of the positive electrode active material, and the coating layer includes one or more of a carbon material, ZrO, TiO, polyaniline, polypyrrole, poly(3,4-ethylenedioxythiophene), aluminum oxide, zinc oxide, titanium oxide, zirconium oxide, magnesium oxide, silicon oxide, lanthanum oxide, sodium fluoride, lithium fluoride, and aluminum fluoride, and the carbon material includes one or more of amorphous carbon, graphite, and graphene.

[0048] By providing a coating layer on the surface of the positive electrode active material, the cycle performance is improved, the gas generation rate of the battery is significantly reduced, and this contributes further to improving the safety of the battery.

[0049] A third aspect of the present application provides a battery module including the secondary battery according to the second aspect of the present application.

[0050] A fourth aspect of the present application provides a battery pack including the secondary battery according to the second aspect of the present application or the battery module according to the third aspect of the present application.

[0051] A fifth aspect of the present application provides a power consumption device including at least one of the secondary battery according to the second aspect of the present application, the battery module according to the third aspect of the present application, and the battery pack according to the fourth aspect of the present application. [Brief explanation of the drawings]

[0052] [Figure 1] 1 is a schematic diagram of a secondary battery according to an embodiment of the present application; [Figure 2] FIG. 2 is an exploded view of the secondary battery according to the embodiment of the present application shown in FIG. [Figure 3] 1 is a schematic diagram of a battery module according to an embodiment of the present application; [Figure 4] 1 is a schematic diagram of a battery pack according to an embodiment of the present application. [Figure 5] FIG. 5 is an exploded view of the battery pack shown in FIG. 4 according to an embodiment of the present application. [Figure 6]1 is a schematic diagram of a power consuming device that uses a secondary battery as a power source according to an embodiment of the present application; DETAILED DESCRIPTION OF THE INVENTION

[0053] Hereinafter, with appropriate reference to the drawings, embodiments specifically disclosing the electrolyte composition, secondary battery, battery module, battery pack, and electric device of the present application will be described in detail. However, unnecessary details may be omitted. For example, detailed descriptions of well-known matters and redundant descriptions of substantially the same structures may be omitted. This is to avoid unnecessary redundancy in the following description and to facilitate easy understanding by those skilled in the art. Furthermore, the drawings and the following description are provided to enable those skilled in the art to fully understand the present application and are not intended to limit the scope of the claims.

[0054] The "ranges" disclosed herein are defined in the form of lower and upper limits. A given range is defined by selecting one lower limit and one upper limit, and the selected lower and upper limits define the boundaries of the particular range. Such defined ranges may be inclusive or exclusive of the endpoints and may be arbitrarily combined; i.e., any lower limit may be combined with any upper limit to form a single range. For example, if ranges of 60 to 120 and 80 to 110 are recited for a given parameter, it is understood that ranges of 60 to 110 and 80 to 120 are also contemplated. Furthermore, if 1 and 2 are recited as minimum range values ​​and 3, 4, and 5 are recited as maximum range values, then the ranges of 1 to 3, 1 to 4, 1 to 5, 2 to 3, 2 to 4, and 2 to 5 are all contemplated. Unless otherwise specified herein, a numerical range "a to b" represents a shorthand notation for any combination of real numbers between a and b, where a and b are both real numbers. For example, the numerical range "0 to 5" means that all real numbers between "0 and 5" are listed herein, and "0 to 5" is simply shorthand for combinations of these numbers. Note that describing a parameter as an integer ≧2 is equivalent to disclosing that the parameter is, for example, the integers 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0055] Unless otherwise stated, all embodiments and alternative embodiments in the present application can be combined with each other to form new technical solutions.

[0056] Unless otherwise stated, all technical features and optional technical features of the present application can be combined with each other to form new technical solutions.

[0057] Unless otherwise specified, all steps herein may be performed in sequence or randomly, preferably in sequence. For example, when the method includes steps (a) and (b), it means that the method may include steps (a) and (b) performed in sequence, or may include steps (b) and (a) performed in sequence. For example, when it is stated that the method may further include step (c), it means that step (c) can be added to the method in any order; for example, the method may include steps (a), (b), and (c), or may include steps (a), (c), and (b), or may include steps (c), (a), and (b).

[0058] Unless otherwise specified, the terms "comprise" and "comprises" used herein may be open-ended or closed-ended. For example, the terms "comprise" and "comprises" may indicate that the compound may further include or include other components not listed, or may include or include only the listed components.

[0059] Unless otherwise stated, the term "or" in this application is inclusive. For example, the phrase "A or B" means "A, B, or both A and B." More specifically, any one of the following conditions satisfies the condition "A or B": A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists); or A and B are both true (or exist).

[0060] While liquid and solid-state electrolytes currently face many challenges, quasi-solid-state electrolytes, which combine the advantages of both liquid and solid-state electrolytes by possessing a liquid component and a consistent geometric shape and strength, have attracted the attention of researchers. Their mechanical performance is crucial for maintaining structural stability during charge / discharge cycles. Therefore, to meet the needs of new-generation electrochemical systems, it is necessary to develop electrolytes that not only possess excellent mechanical performance but also the advantages of quasi-solid-state electrolytes.

[0061] [Electrolyte composition] Based on this, the present application proposes an electrolyte composition, which is a non-Newtonian fluid electrolyte composition.

[0062] As used herein, non-Newtonian fluids refer to fluids whose rheological properties do not satisfy Newton's empirical law of viscosity, i.e., the fluid does not have a linear relationship between shear stress and shear rate.

[0063] The non-Newtonian fluid electrolyte composition can undergo mechanical thixotropy, i.e., change from a flowable state to a solid state, under the action of a certain external force, thereby effectively improving the short-circuit prevention safety and impact resistance of the battery. Furthermore, compared with other electrolytes with high viscosity, the non-Newtonian fluid electrolyte composition can achieve the lowest electrolyte ohmic resistance and interfacial resistance at low stacking pressure, improving the battery assembly process.

[0064] In some embodiments, after stirring the electrolyte composition for 10 seconds while rotating at 25°C using a 62# or 64# rotor on a Dveslvtjo rotational viscosity tester at a speed of 12 rpm, the viscosity of the electrolyte composition is 1000 mPa·s to 50000 mPa·s.

[0065] In some embodiments, after stirring the electrolyte composition for 10 seconds while rotating at 25°C with a 62# or 64# rotor in a Dveslvtjo rotational viscosity tester at a speed of 12 revolutions per minute, the upper or lower viscosity limit of the electrolyte composition is optionally 1000 mPa·s, 2000 mPa·s, 3000 mPa·s, 4000 mPa·s, 5000 mPa·s, 6000 mPa·s, 7000 mPa·s, 8000 mPa·s, 9000 mPa·s, 1000 mPa·s, 11000 mPa·s, 12000 mPa·s, 13000 mPa·s, 14000 mPa·s, 15000 mPa·s, 16000 mPa·s, 17000 mPa·s, 18000 mPa·s, 19000 mPa·s, 21000 mPa·s, 22000 mPa·s, 23000 mPa·s, 24000 mPa·s, 25000 mPa·s, 26000 mPa·s, 27000 mPa·s, 28000 mPa·s, 29000 mPa·s, 3000 mPa·s, 31000 mPa·s, 32000 mPa·s, 33000 mPa·s, 34000 mPa·s, 35000 mPa·s, 36000 mPa·s, 37000 mPa·s, 38000 mPa·s, 39000 mPa·s, 4000 mPa·s, 41000 mPa·s, 42000 mPa·s, 4 The viscosity may be 1000mPa·s, 8000mPa·s, 9000mPa·s, 10000mPa·s, 12000mPa·s, 14000mPa·s, 16000mPa·s, 18000mPa·s, 20000mPa·s, 25000mPa·s, 30000mPa·s, 35000mPa·s, 40000mPa·s, 45000mPa·s or 50000mPa·s.

[0066] In this specification, the viscosity of non-Newtonian fluid electrolyte compositions is tested using a Brookfield Dveslvtjo rotational viscometer. The test conditions are a temperature of 25°C, a test time of 10 seconds, a 64# rotor for measuring viscosities of 2000 mPa·s or more, and a 62# rotor for measuring viscosities of less than 2000 mPa·s, with a rotor rotation speed of 12 rpm. Three parallel measurements are taken and the average value is calculated. Compared to batteries using liquid electrolytes with similar compositions, the high viscosity of non-Newtonian fluid electrolyte compositions effectively suppresses gas generation in batteries, further improving battery cycle performance.

[0067] In some embodiments, after stirring the electrolyte composition for 10 minutes while rotating at 25°C with a 62# or 64# rotor in a Dveslvtjo rotational viscosity tester at a speed of 12 revolutions per minute, the viscosity of the electrolyte composition increases by more than 100 mPa·s compared to the viscosity after 10 seconds of testing under the same conditions.

[0068] In some embodiments, after stirring the electrolyte composition for 10 minutes while rotating at 12 revolutions per minute using a 62# or 64# rotor in a Dveslvtjo rotational viscosity tester at 25°C, the increase in viscosity of the electrolyte composition relative to the viscosity after testing for 10 seconds under the same conditions is optionally 100 mPa·s, 300 mPa·s, 500 mPa·s, 700 mPa·s, 900 mPa·s, 1000 mPa·s, 1200 mPa·s, 1400 mPa·s, 1600 mPa·s, 1800 mPa·s, 2000 mPa·s, 2200 mPa·s, 2400 mPa·s, 2600 mPa·s, 2800 mPa·s, or 3000 mPa·s.

[0069] Non-Newtonian fluid electrolyte compositions fail to satisfy Newton's law of viscosity, i.e., there is a non-linear relationship between shear stress and shear strain rate. As used herein, non-Newtonian fluid electrolyte compositions are shear-thickening liquids, which increase in viscosity with increasing shear rate or shear time.

[0070] In some embodiments, the non-Newtonian fluid electrolyte composition exhibits a drop in loss factor after mechanical thixotropy relative to the loss factor before mechanical thixotropy of more than 10%.

[0071] As used herein, mechanical thixotropy refers to the change from a flowable state to a solid state upon application of a certain external force to an electrolyte composition.

[0072] In some embodiments, mechanical thixotropy of the electrolyte composition is achieved by nail penetration. For example, a tensile tester and nail penetration jig manufactured by Gaotie Corporation are used to perform nail penetration of a battery based on the electrolyte composition. A 1 mm diameter nail is used in the nail penetration tester, and the nail penetration rate is 6 mm / min, resulting in a nail penetration depth of 2 mm. In some embodiments, mechanical thixotropy of the electrolyte composition is achieved by compression. For example, a semi-cylindrical pressure plate with a radius of 75 mm is pressed against the battery perpendicular to the direction of the battery's electrode plates, and the compression rate is 60 mm / min.

[0073] As used herein, the term "loss factor" refers to the ratio of the loss modulus to the storage modulus.

[0074] Herein, the loss factor of a non-Newtonian fluid electrolyte composition can be tested using a method known in the art. For example, a sample is cut into a disk shape with a diameter of 20 mm and a thickness of 1 mm, the test instrument is a Haake rheometer, the test temperature is 25°C, the strain sweep range is 0.1% to 1000%, and the fixed frequency is 1 Hz, and the storage modulus (G') and loss modulus (G") are obtained, respectively, and the loss factor The formula for TIFF2025535385000002.tif6170 is The file is TIFF2025535385000003.tif6150.

[0075] As used herein, the term "decline rate" = (loss factor before mechanical thixotropy - loss factor after mechanical thixotropy) / loss factor before mechanical thixotropy.

[0076] In some embodiments, the non-Newtonian fluid electrolyte composition exhibits a decrease in loss factor after mechanical thixotropy relative to the loss factor before mechanical thixotropy of optionally 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 60%, 65%, 70%, or 75%.

[0077] When subjected to external forces such as nail penetration or pressure, the non-Newtonian fluid electrolyte composition changes from a flowable state to a solid state, and the phase change causes a decrease in its loss factor. The decrease in the loss factor of the non-Newtonian fluid electrolyte composition is more than 10%, i.e., the storage modulus is significantly increased, thereby effectively improving the safety and impact resistance of the battery in the event of an accident such as nail penetration.

[0078] In some embodiments, the non-Newtonian fluid electrolyte composition includes at least one of an organic solvent and an ionic liquid, an electrolyte salt, and suspended particles.

[0079] As used herein, the term "organic solvent" refers to an organic compound that has dielectric properties, is capable of dissolving electrolyte salts, and contains carbon atoms.

[0080] As used herein, the term "ionic liquid" refers to a liquid that has no dielectric properties, is capable of dissociating an electrolyte salt, and is composed of ions.

[0081] As used herein, the term "electrolyte salt" refers to a compound in which metal ions and acid ions are combined, and the electrolyte salt is itself capable of conducting electricity when dissolved in an aqueous solution or in a molten state.

[0082] As used herein, the term "suspended particles" refers to particles that are uniformly dispersed in a non-Newtonian electrolyte composition system, and the suspended particles include, but are not limited to, one or more of organic particles and inorganic particles.

[0083] In some embodiments, the non-Newtonian fluid electrolyte composition includes an organic solvent, an electrolyte salt, and suspended particles.

[0084] In some embodiments, the non-Newtonian fluid electrolyte composition comprises an ionic liquid, an electrolyte salt, and suspended particles.

[0085] A non-Newtonian fluid electrolyte composition comprising an electrolyte salt, an ionic liquid, and suspended particles, or a non-Newtonian fluid electrolyte composition comprising an electrolyte salt, an organic solvent, and suspended particles, has excellent safety and impact resistance, and at the same time, can achieve the lowest electrolyte ohmic resistance and interfacial resistance at low stacking pressure, and the battery assembly process is simpler.

[0086] In some embodiments, the non-Newtonian fluid electrolyte composition further comprises a polymer.

[0087] In some embodiments, the non-Newtonian fluid electrolyte composition includes an organic solvent, an electrolyte salt, a polymer, and suspended particles.

[0088] In some embodiments, the non-Newtonian fluid electrolyte composition includes an ionic liquid, an electrolyte salt, a polymer, and suspended particles.

[0089] The introduction of polyethylene oxide into the non-Newtonian fluid electrolyte composition contributes to improving the cycle performance of the battery, lowering the battery swelling rate, reducing the gas generation rate, and improving the safety of the battery.

[0090] In some embodiments, the electrolyte salt comprises a sodium salt, which comprises one or more of sodium chloride, sodium bromide, sodium nitrate, sodium perchlorate, sodium hexafluorophosphate, sodium acetate, sodium trifluoroacetate, sodium trifluoromethanesulfonate, sodium bis(fluorosulfonyl)imide, sodium bis(trifluoromethanesulfonyl)imide, optionally one or more of sodium trifluoromethanesulfonate, sodium bis(fluorosulfonyl)imide, sodium bis(trifluoromethanesulfonyl)imide.

[0091] In some embodiments, the sodium salt includes sodium chloride. In some embodiments, the sodium salt includes sodium bromide. In some embodiments, the sodium salt includes sodium hexafluorophosphate. In some embodiments, the sodium salt includes sodium tetrafluoroborate. In some embodiments, the sodium salt includes sodium trifluoromethanesulfonate. In some embodiments, the sodium salt includes sodium bis(fluorosulfonyl)imide. In some embodiments, the sodium salt includes sodium bis(fluorosulfonyl)imide and sodium bis(trifluoromethanesulfonyl)imide. In some embodiments, the sodium salt includes sodium tetrafluoroborate and sodium bis(fluorosulfonyl)imide.

[0092] The sodium salt enhances the safety and impact resistance of the non-Newtonian fluid electrolyte composition, enhances the cycle performance of the battery, and reduces the gas generation rate of the battery and the stacking pressure at which the ohmic resistance and interfacial resistance of the electrolyte are minimized, thereby contributing to enhancing battery safety and improving the battery assembly process. Selectively controlling the sodium salt to include one or more of sodium trifluoromethanesulfonate, sodium bis(fluorosulfonyl)imide, and sodium bis(trifluoromethanesulfonyl)imide contributes to further enhancing the cycle performance of the battery.

[0093] In some embodiments, the organic solvent comprises one or more of an ether organic solvent, an ester organic solvent, a sulfur-containing organic solvent, including one or more of ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, ethylene carbonate, propylene carbonate, butylene carbonate, vinylene carbonate, fluoroethylene carbonate, ethyl methyl carbonate, dimethyl carbonate, diethyl carbonate, dipropyl carbonate, dimethyl sulfoxide, and optionally ethylene glycol dimethyl ether.

[0094] In some embodiments, the organic solvent comprises ethylene glycol dimethyl ether. In some embodiments, the organic solvent comprises diethylene glycol dimethyl ether. In some embodiments, the organic solvent comprises triethylene glycol dimethyl ether. In some embodiments, the organic solvent comprises tetraethylene glycol dimethyl ether. In some embodiments, the solvent comprises ethylene carbonate. In some embodiments, the organic solvent comprises ethylene glycol dimethyl ether and ethylene carbonate. In some embodiments, the organic solvent comprises ethylene glycol dimethyl ether and diethylene glycol dimethyl ether.

[0095] The organic solvent enhances the safety and impact resistance of the non-Newtonian fluid electrolyte composition, reduces the stacking pressure of the battery when the ohmic resistance and interfacial resistance of the electrolyte are minimized, and contributes to improving the battery assembly process. Selectively controlling the organic solvent to contain ethylene glycol dimethyl ether further enhances the safety and impact resistance of the non-Newtonian fluid electrolyte composition, improves the cycle performance of the battery to a greater extent, and significantly reduces the gas generation rate of the battery, contributing to improving the safety of the battery.

[0096] In some embodiments, the ionic liquid comprises one or more of 1-butyl-3-methylimidazolium chloride, 1-alkyl-3-methylimidazolium tetrafluoroborate, N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide, 5-azoniaspiro[4,4]nonane hexafluorophosphate, trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide, tetrabutylphosphonium hexafluorophosphate, optionally comprising one or more of N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide, trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide.

[0097] In some embodiments, the ionic liquid includes 1-butyl-3-methylimidazolium chloride. In some embodiments, the ionic liquid includes 1-alkyl-3-methylimidazolium tetrafluoroborate. In some embodiments, the ionic liquid includes N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide. In some embodiments, the ionic liquid includes trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide. In some embodiments, the ionic liquid includes tetrabutylphosphonium hexafluorophosphate. In some embodiments, the ionic liquid includes 1-butyl-3-methylimidazolium chloride and tetrabutylphosphonium hexafluorophosphate. In some embodiments, the ionic liquid includes N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide and trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide.

[0098] The ionic liquid enhances the safety and impact resistance of the non-Newtonian fluid electrolyte composition, reduces the stacking pressure of the battery when the ohmic resistance and interfacial resistance of the electrolyte are minimized, and contributes to improving the battery assembly process. By selectively controlling the ionic liquid to include one or more of N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide and trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide, the safety and impact resistance of the non-Newtonian fluid electrolyte composition can be further enhanced, the cycle performance of the battery can be improved to a greater extent, and the gas generation rate of the battery and the stacking pressure when the ohmic resistance and interfacial resistance of the electrolyte are minimized can be significantly reduced, thereby enhancing battery safety and improving the battery assembly process.

[0099] In some embodiments, the polymer comprises polyethylene oxide, polyethylene glycol, polyvinylpyrrolidone, polymethylmethacrylate, polyvinylidene fluoride, polyvinyl alcohol, polyacrylamide, and optionally one or more of polyethylene oxide, polyethylene glycol.

[0100] In some embodiments, the polymer comprises polyethylene oxide. In some embodiments, the polymer comprises polyethylene glycol. In some embodiments, the polymer comprises polyvinylpyrrolidone. In some embodiments, the polymer comprises polymethyl methacrylate. In some embodiments, the polymer comprises polyvinylidene fluoride. In some embodiments, the polymer comprises polyvinylidene fluoride and polyethylene oxide. In some embodiments, the polymer comprises polyethylene glycol and polyethylene oxide.

[0101] The polymer enhances the safety and impact resistance of the non-Newtonian fluid electrolyte composition, and reduces the gas generation rate of the battery and the stacking pressure at which the ohmic resistance and interfacial resistance of the electrolyte are minimized, thereby improving battery safety and improving the battery assembly process. By selectively controlling the polymer to contain one or more of polyethylene oxide and polyethylene glycol, the cycle performance of the battery can be further improved, and the stacking pressure at which the ohmic resistance and interfacial resistance of the electrolyte are minimized can be significantly reduced, contributing to an improvement in the battery assembly process.

[0102] In some embodiments, the suspended particles include one or more of fumed silica, aluminum oxide, sodium oxide, lithium oxide, sodium fluoride, lithium fluoride, polyurethane, and optionally one or more of fumed silica, sodium oxide, and lithium oxide.

[0103] In some embodiments, the suspended particles comprise fumed silica. In some embodiments, the suspended particles comprise aluminum oxide. In some embodiments, the suspended particles comprise sodium oxide. In some embodiments, the suspended particles comprise sodium fluoride. In some embodiments, the suspended particles comprise polyurethane. The suspended particles comprise fumed silica and sodium oxide. The suspended particles comprise fumed silica and lithium fluoride. The suspended particles comprise sodium oxide and lithium fluoride. The suspended particles comprise fumed silica and polyurethane.

[0104] The suspended particles enhance the safety and impact resistance of the non-Newtonian fluid electrolyte composition, reduce the stacking pressure of the battery when the ohmic resistance and interfacial resistance of the electrolyte are minimized, and contribute to improving the battery assembly process. By selectively controlling the suspended particles to include one or more of fumed silica, sodium oxide, and lithium oxide, the cycle performance of the battery can be further improved, the gas generation rate of the battery can be significantly reduced, and the safety of the battery can be improved.

[0105] In some embodiments, the electrolyte salt comprises one or more of sodium trifluoromethanesulfonate, sodium bis(fluorosulfonyl)imide, and sodium bis(trifluoromethanesulfonyl)imide; the organic solvent comprises ethylene glycol dimethyl ether; the ionic liquid comprises one or more of N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide and trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide; the polymer comprises one or more of polyethylene oxide and polyethylene glycol; and the suspended particles comprise one or more of fumed silica, sodium oxide, and lithium oxide.

[0106] In some embodiments, the electrolyte salt comprises sodium trifluoromethanesulfonate, the organic solvent comprises ethylene glycol dimethyl ether, the polymer comprises polyethylene oxide, and the suspended particles comprise fumed silica. In some embodiments, the electrolyte salt comprises sodium bis(fluorosulfonyl)imide, the ionic liquid comprises N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide, the polymer comprises polyethylene oxide, and the suspended particles comprise fumed silica.

[0107] The selection of the electrolyte salt, organic solvent, ionic liquid, polymer and suspended particles contributes to improving the cycle performance of the battery.

[0108] In some embodiments, the electrolyte salt comprises one or more of sodium trifluoromethanesulfonate, sodium bis(fluorosulfonyl)imide, sodium bis(trifluoromethanesulfonyl)imide, the organic solvent comprises ethylene glycol dimethyl ether, and the suspended particles comprise one or more of fumed silica, sodium oxide, and lithium oxide.

[0109] In some embodiments, the electrolyte salt comprises sodium trifluoromethanesulfonate, the organic solvent comprises ethylene glycol dimethyl ether, and the suspended particles comprise fumed silica. In some embodiments, the electrolyte salt comprises sodium bis(fluorosulfonyl)imide, the organic solvent comprises ethylene glycol dimethyl ether, and the suspended particles comprise lithium oxide. In some embodiments, the electrolyte salt comprises sodium bis(trifluoromethanesulfonyl)imide, the organic solvent comprises ethylene glycol dimethyl ether, and the suspended particles comprise fumed silica.

[0110] The non-Newtonian fluid electrolyte composition comprising the above-mentioned electrolyte salt, organic solvent and suspended particles enhances the safety and impact resistance of the non-Newtonian fluid electrolyte composition, improves the cycle performance of the battery, and reduces the gas generation rate of the battery and the stacking pressure at which the ohmic resistance and interfacial resistance of the electrolyte are minimized, thereby contributing to improving the safety of the battery and the battery assembly process.

[0111] In some embodiments, the electrolyte salt comprises one or more of sodium trifluoromethanesulfonate, sodium bis(fluorosulfonyl)imide, sodium bis(trifluoromethanesulfonyl)imide, the organic solvent comprises ethylene glycol dimethyl ether, the polymer comprises one or more of polyethylene oxide, polyethylene glycol, and the suspended particles comprise one or more of fumed silica, sodium oxide, and lithium oxide.

[0112] In some embodiments, the electrolyte salt comprises sodium trifluoromethanesulfonate, the organic solvent comprises ethylene glycol dimethyl ether, the polymer comprises polyethylene oxide, and the suspended particles comprise fumed silica. In some embodiments, the electrolyte salt comprises sodium bis(fluorosulfonyl)imide, the organic solvent comprises ethylene glycol dimethyl ether, the polymer comprises polyethylene glycol, and the suspended particles comprise lithium oxide. In some embodiments, the electrolyte salt comprises sodium bis(trifluoromethanesulfonyl)imide, the organic solvent comprises ethylene glycol dimethyl ether, the polymer comprises polyethylene oxide and polyethylene glycol, and the suspended particles comprise sodium oxide.

[0113] The non-Newtonian fluid electrolyte composition comprising the above-mentioned electrolyte salt, organic solvent, polymer and suspended particles enhances the safety and impact resistance of the non-Newtonian fluid electrolyte composition, improves the cycle performance of the battery, and reduces the gas generation rate of the battery and the stacking pressure at which the ohmic resistance and interfacial resistance of the electrolyte are minimized, thereby contributing to improving the safety of the battery and the battery assembly process.

[0114] In some embodiments, the electrolyte salt comprises one or more of sodium trifluoromethanesulfonate, sodium bis(fluorosulfonyl)imide, sodium bis(trifluoromethanesulfonyl)imide, the ionic liquid comprises one or more of N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide, trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide, and the suspended particles comprise one or more of fumed silica, sodium oxide, and lithium oxide.

[0115] In some embodiments, the electrolyte salt includes sodium trifluoromethanesulfonate, the ionic liquid includes N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide, and the suspended particles include fumed silica. In some embodiments, the electrolyte salt includes sodium bis(fluorosulfonyl)imide, the ionic liquid includes N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide, and the suspended particles include sodium oxide. In some embodiments, the electrolyte salt includes sodium bis(trifluoromethanesulfonyl)imide, the ionic liquid includes N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide and trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide, and the suspended particles include lithium oxide.

[0116] The non-Newtonian fluid electrolyte composition comprising the above-mentioned electrolyte salt, ionic liquid and suspended particles enhances the safety and impact resistance of the non-Newtonian fluid electrolyte composition, and reduces the stacking pressure of the battery when the ohmic resistance and interfacial resistance of the electrolyte are minimized, thereby contributing to an improvement in the battery assembly process.

[0117] In some embodiments, the electrolyte salt comprises one or more of sodium trifluoromethanesulfonate, sodium bis(fluorosulfonyl)imide, sodium bis(trifluoromethanesulfonyl)imide; the ionic liquid comprises one or more of N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide, trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide; the polymer comprises one or more of polyethylene oxide, polyethylene glycol; and the suspended particles comprise one or more of fumed silica, sodium oxide, and lithium oxide.

[0118] In some embodiments, the electrolyte salt includes sodium trifluoromethanesulfonate, the ionic liquid includes N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide, the polymer includes polyethylene oxide, and the suspended particles include fumed silica. In some embodiments, the electrolyte salt includes sodium bis(fluorosulfonyl)imide, the ionic liquid includes N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide, the polymer includes polyethylene oxide and polyethylene glycol, and the suspended particles include lithium oxide. In some embodiments, the electrolyte salt includes sodium bis(trifluoromethanesulfonyl)imide, the ionic liquid includes N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide and trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide, the polymer includes polyethylene glycol, and the suspended particles include fumed silica and lithium oxide.

[0119] The non-Newtonian fluid electrolyte composition comprising the above-mentioned electrolyte salt, ionic liquid, polymer and suspended particles enhances the safety and impact resistance of the non-Newtonian fluid electrolyte composition, reduces the stacking pressure of the battery when the ohmic resistance and interfacial resistance of the electrolyte are minimized, and contributes to improving the battery assembly process.

[0120] In some embodiments, based on the total mass of the non-Newtonian fluid electrolyte composition, the mass content of the electrolyte salt is 5% to 20%, the mass content of the organic solvent is 20% to 60%, the mass content of the ionic liquid is 20% to 60%, the mass content of the polymer is 0% to 40%, and the mass content of the suspended particles is greater than 0 and less than or equal to 20%.

[0121] In some embodiments, based on the total weight of the non-Newtonian fluid electrolyte composition, the weight content of the electrolyte salt is optionally 5%, 6%, 8%, 10%, 12%, 14%, 15%, 16%, 18%, or 20%, the weight content of the organic solvent is optionally 20%, 22%, 25%, 30%, 35%, 38%, 40%, 45%, 47%, 50%, 53%, 55%, 60%, 62%, or 65%, and the weight content of the ionic liquid is optionally 20%, 22%, 25%, 30%, 35%, 38%, 40%, 45%, 47%, 50%, 53%, 55%, 60%, 62%, or 65%. 0%, 35%, 38%, 40%, 45%, 47%, 50%, 53%, 55%, 60%, 62% or 65%, the polymer mass content is optionally 0%, 5%, 6%, 8%, 10%, 12%, 14%, 15%, 16%, 18%, 20%, 22%, 25%, 28%, 30%, 35%, 38% or 40%, and the suspended particle mass content is optionally 1%, 2%, 4%, 5%, 6%, 8%, 10%, 12%, 14%, 15%, 16%, 18% or 20%.

[0122] By controlling the appropriate mass content of electrolyte salt, organic solvent, ionic liquid, polymer, and suspended particles, the safety and impact resistance of the non-Newtonian fluid electrolyte composition can be improved, the cycle performance of the battery can be enhanced, and the stacking pressure at which the gas generation rate of the battery and the ohmic resistance and interfacial resistance of the electrolyte are minimized can be reduced, thereby improving the safety of the battery and improving the battery assembly process.

[0123] In some embodiments, the non-Newtonian fluid electrolyte composition has a compressive strength of 35 kN to 200 kN.

[0124] In this specification, the pressure strength when the open circuit voltage becomes zero is mainly used to characterize the pressure experienced by the non-Newtonian fluid electrolyte composition when the battery is short-circuited, and can reflect the impact resistance performance of the non-Newtonian fluid electrolyte composition, and can be tested by any known method. For example, a semi-cylindrical pressure plate with a radius of 75 mm is placed perpendicular to the direction of the battery plate, and the pressure speed is set to 60 mm / min. The changes in the open circuit voltage of the battery and the pressure applied by the pressure plate are observed, and the pressure applied by the pressure plate when the open circuit voltage is zero is recorded.

[0125] The non-Newtonian fluid electrolyte composition has an appropriate compressive strength, improves the impact resistance performance, and contributes to enhancing the safety and reliability of the battery.

[0126] [Positive electrode] The positive electrode plate includes a positive electrode current collector and a positive electrode active material layer formed on at least a portion of the surface of the positive electrode current collector, the positive electrode active material layer including a positive electrode active material, and the positive electrode active material can include at least one of a layered transition metal oxide, a polyanion-type compound, and a Prussian blue compound.

[0127] The transition metal in the layered transition metal oxide may be at least one of Mn, Fe, Ni, Co, Cr, Cu, Ti, Zn, V, Zr, and Ce. Optionally, the layered transition metal oxide may be, for example, Na x MO2, where M is one or more of Ti, V, Mn, Co, Ni, Fe, Cr, and Cu; <x≦1である。

[0128] Polyanionic compounds include metal ions, transition metal ions, and tetrahedral (YO4) n- The compound may have an anionic unit, wherein the metal ion is optionally one of sodium ion, lithium ion, potassium ion, and zinc ion, the transition metal is optionally at least one of Mn, Fe, Ni, Co, Cr, Cu, Ti, Zn, V, Zr, and Ce, Y is optionally at least one of P, S, and Si, and n is (YO4) n- represents the valence state of

[0129] The Prussian blue compound may be a compound having a sodium ion, a transition metal ion, and a cyanide ion (CN-). The transition metal may be at least one of Mn, Fe, Ni, Co, Cr, Cu, Ti, Zn, V, Zr, and Ce. The Prussian blue compound may be, for example, Na a Me b Me' c (CN)6, where Me and Me' are each independently at least one of Ni, Cu, Fe, Mn, Co, and Zn; <a≦2、0<b<1、0<c<1である。

[0130] In some embodiments, the positive electrode plate includes a positive electrode active material, the positive electrode active material including at least one of a layered transition metal oxide, a polyanionic compound, and a Prussian blue compound, and the positive electrode active material includes NaNi 1 / 3 Fe 1 / 3 Mn 1 / 3 O2, Na(Cu 1 / 9 Ni 2 / 9 Fe 1 / 3 Mn 1 / 3 )O2, Na 2 / 3 Ni 1 / 6 Mn 2 / 3 Cu 1 / 9 Mg 1 / 18 O2, Na4Fe3(PO4)2P2O7, NaFePO4, Na3V2(PO4)3, Na 1.9 CoFe(CN)6, Na2NiFe(CN)6, NaMnFe(CN)6.

[0131] Any of the above positive electrode active materials can provide the battery with excellent cycle performance and safety.

[0132] In some embodiments, the positive electrode active material has a coating layer on its surface, the coating layer including one or more of a carbon material, ZrO, TiO, polyaniline, polypyrrole, poly(3,4-ethylenedioxythiophene), aluminum oxide, zinc oxide, titanium oxide, zirconium oxide, magnesium oxide, silicon oxide, lanthanum oxide, sodium fluoride, lithium fluoride, and aluminum fluoride, and the carbon material includes one or more of amorphous carbon, graphite, and graphene.

[0133] As used herein, the term "amorphous carbon" refers to a carbon material that has a very low degree of graphitization or crystallization and approximates an amorphous state, and does not have a specific shape or periodic structure. Examples of amorphous carbon include, but are not limited to, carbon black, charcoal, or coke.

[0134] As used herein, the term "graphite" refers to an allotrope of carbon and includes natural graphite and artificial graphite.

[0135] As used herein, the term "graphene" refers to sp 2 It refers to a carbon material in which carbon atoms connected by hybridization are densely stacked in a single layer, two-dimensional honeycomb lattice structure. By way of example, graphene includes, but is not limited to, single-layer graphene and multi-layer graphene.

[0136] As used herein, the term "single-layer graphene" refers to a single-layer sheet structure in which carbon atoms are densely and periodically arranged in a hexagonal honeycomb structure. For example, the thickness of single-layer graphene is only 0.3 nm to 0.4 nm.

[0137] In this specification, the term "multilayer graphene" refers to a graphene produced by stacking 2 to 10 single-layer graphene layers, the total thickness of which is less than 100 nm.

[0138] By providing a coating layer on the surface of the positive electrode active material, the cycle performance is improved, the gas generation rate of the battery is significantly reduced, and this contributes further to improving the safety of the battery.

[0139] The positive electrode active material layer may further include a conductive agent to improve the conductive performance of the positive electrode, which may be one or more of Super P, acetylene black, carbon black, ketjen black, carbon dots, carbon nanotubes, graphite, graphene, and carbon nanofibers.

[0140] The positive electrode active material layer may further include a binder to firmly bond the positive electrode active material and optional conductive agent to the positive electrode current collector, and the binder may optionally be at least one of polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), polyacrylic acid (PAA), polyethylene alcohol (PVA), ethylene-vinyl acetate copolymer (EVA), styrene-butadiene rubber (SBR), carboxymethyl cellulose (CMC), sodium alginate (SA), polymethacrylic acid (PMA), and carboxymethyl chitosan (CMCS).

[0141] The positive electrode current collector may be a conductive carbon sheet, metal foil, carbon-coated metal foil, porous metal plate, or composite current collector. The conductive carbon material of the conductive carbon sheet may be one or more of Super P, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphite, graphene, and carbon nanofibers. The metal material of the metal foil, carbon-coated metal foil, and porous metal plate may each independently be at least one selected from copper, aluminum, nickel, and stainless steel. The composite current collector may be a composite current collector formed by combining a metal foil with a polymer-based film.

[0142] In some embodiments, a positive electrode plate can be manufactured by the following method. The components for manufacturing the positive electrode plate described above, such as the positive electrode active material, conductive agent, binder, and any other optional components, are dispersed in a solvent (e.g., N-methylpyrrolidone) to form a positive electrode slurry. The positive electrode slurry is applied to a positive electrode current collector, and after processes such as drying and cold pressing, a positive electrode plate can be obtained.

[0143] [Negative electrode] The negative electrode plate may include only a negative electrode current collector without including a negative electrode active material. In the negative electrode plate, a metal phase may be pre-deposited on the negative electrode current collector.

[0144] In some embodiments, the negative electrode current collector may be a metal foil or a composite current collector. For example, the metal foil may be an aluminum foil or a copper foil. The composite current collector may include a polymeric base layer and a metal layer formed on at least one surface of the polymeric substrate. The composite current collector may be formed by forming a metal material (such as copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver, or silver alloy) on a polymeric substrate (such as a substrate of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), or polyethylene (PE)).

[0145] In some embodiments, the negative electrode plate includes a negative electrode current collector and an undercoat layer provided on at least one surface of the negative electrode current collector, the undercoat layer including one or more of carbon nanotubes, graphite, graphene, silver-composite carbon nanoparticles, and tin-composite carbon nanoparticles.

[0146] In some embodiments, the areal density of the primer layer is 2 to 50 g / m 2 is.

[0147] In some embodiments, the thickness of the undercoat layer is 1 to 100 μm.

[0148] [Separator] In some embodiments, the secondary battery further includes a separator. In the present application, the type of separator is not particularly limited, and any separator with a known porous structure having good chemical stability and mechanical stability can be selected.

[0149] In some embodiments, the separator may be made of at least one of polyethylene, polypropylene, polyvinylidene fluoride, aramid fiber, polyethylene terephthalate, polytetrafluoroethylene, polyacrylonitrile, polyimide, polyamide, polyester, and natural fiber. The separator may be a single-layer film or a multi-layer composite film, and is not particularly limited. When the separator is a multi-layer composite film, the materials of the layers may be the same or different, and are not particularly limited.

[0150] In some embodiments, the positive electrode plates, negative electrode plates, and separator can be manufactured into an electrode assembly by a winding process or a stacking process.

[0151] In some embodiments, the secondary battery may include an exterior body that can be used to package the electrode assembly and the electrolyte.

[0152] In some embodiments, the exterior of the secondary battery may be a hard case, such as a hard plastic case, an aluminum case, or a steel case. The exterior of the secondary battery may be a soft pack, such as a bag-type soft pack. The soft pack may be made of plastic, such as polypropylene, polybutylene terephthalate, or polybutylene succinate.

[0153] [Secondary battery] The secondary battery includes a positive electrode plate and, in some embodiments, a non-Newtonian fluid electrolyte composition.

[0154] In the present application, the shape of the secondary battery is not particularly limited, and may be cylindrical, rectangular, or any other shape. For example, Fig. 2 shows a secondary battery 5 having a rectangular structure as an example.

[0155] In some embodiments, the secondary battery further comprises a negative electrode plate and a separator.

[0156] In some embodiments, the secondary battery includes at least one of a lithium battery and a sodium battery.

[0157] In some embodiments, the secondary battery includes at least one of a potassium battery, a magnesium battery, and a zinc battery.

[0158] In some embodiments, the secondary battery is a negative electrode-free sodium battery.

[0159] Anode-free sodium batteries do not have a pre-deposited anode active material and only contain anode current collectors. During initial charging, sodium ions gain electrons at the cathode and deposit as metallic sodium on the surface of the current collector, forming a sodium metal phase. During discharge, the metallic sodium can convert back to sodium ions and return to the cathode, achieving charge-discharge cycling. Compared with sodium-ion secondary batteries and sodium metal batteries, anode-free sodium batteries are not limited by the anode material and therefore can achieve higher energy densities. Anode-free sodium batteries lack sufficient sodium metal as anode material to provide sufficient sodium element to the battery. Therefore, applying a non-Newtonian fluid electrolyte composition to anode-free sodium batteries can more effectively improve the cycle performance and safety performance of secondary batteries at room and high temperatures.

[0160] In some embodiments, the CB value of the negative electrode-free sodium battery is 0.1 or less.

[0161] The CB value is the capacity per unit area of ​​the negative electrode plate in a secondary battery divided by the capacity per unit area of ​​the positive electrode plate. Because anode-free batteries do not contain negative electrode active material, the capacity per unit area of ​​the negative electrode plate is small, and the CB value of secondary batteries is 0.1 or less.

[0162] In some embodiments, referring to FIG. 3 , the exterior body may include a case 51 and a cover plate 53. The case 51 may include a bottom plate and a side plate connected to the bottom plate, with the bottom plate and the side plate being enclosed to form a storage chamber. The case 51 may have an opening communicating with the storage chamber, and the cover plate 53 may cover the opening to seal the storage chamber. The positive electrode plate, the negative electrode plate, and the separator may be formed into an electrode assembly 52 by a winding process or a stacking process. The electrode assembly 52 is packaged in the storage chamber. A non-Newtonian fluid electrolyte composition is infiltrated into the electrode assembly 52. ​​The number of electrode assemblies 52 included in the lithium ion battery 5 may be one or more, and can be selected by those skilled in the art according to specific actual needs.

[0163] [Battery module] In some embodiments, the secondary batteries can be assembled into a battery module, and the number of secondary batteries included in the battery module can be one or more, and the specific number can be selected by those skilled in the art according to the application and capacity of the battery module.

[0164] Fig. 4 shows an example of a battery module 4. Referring to Fig. 4, in the battery module 4, the plurality of secondary batteries 5 may be arranged in order along the longitudinal direction of the battery module 4. Of course, they may be arranged in any other manner. Furthermore, the plurality of secondary batteries 5 may be fixed by fastening members.

[0165] Optionally, the battery module 4 may further include a housing having an accommodating space, and the plurality of secondary batteries 5 are accommodated in the accommodating space.

[0166] [Battery pack] In some embodiments, the battery modules can be further assembled into a battery pack, and the number of battery modules included in the battery pack can be one or more, and the specific number can be selected by those skilled in the art according to the application and capacity of the battery pack.

[0167] 5 and 6 show an example of a battery pack 1. Referring to FIGS. 5 and 6, the battery pack 1 may include a battery box and a plurality of battery modules 4 provided in the battery box. The battery box may include an upper box 2 and a lower box 3, and the upper box 2 may cover the lower box 3 to form a sealed space for accommodating the battery modules 4. The plurality of battery modules 4 may be arranged in the battery box in any desired form.

[0168] [Power consumption equipment] In one embodiment of the present application, there is provided a power consuming device including at least one of the secondary battery according to any of the embodiments, the battery module according to any of the embodiments, or the battery pack according to any of the embodiments.

[0169] The power consuming device includes at least one of a secondary battery, a battery module, or a battery pack provided by the present application. The secondary battery, the battery module, or the battery pack may be used as a power source for the power consuming device or as an energy storage unit for the power consuming device. The power consuming device may include, but is not limited to, mobile devices (e.g., mobile phones, notebook computers, etc.), electric vehicles (e.g., rechargeable battery electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, electric bicycles, electric scooters, electric golf carts, electric trucks, etc.), electric cars, ships and satellites, energy storage systems, etc.

[0170] As the power consuming device, a secondary battery, a battery module or a battery pack can be selected according to the needs of the usage.

[0171] 7 shows an example of a power consuming device, such as a secondary battery electric vehicle, a hybrid electric vehicle, or a plug-in hybrid electric vehicle. A battery pack or a battery module can be employed to meet the high power and high energy density requirements of the secondary battery of the power consuming device.

[0172] Other example devices may be mobile phones, tablets, laptops, etc. Such devices typically require light weight and thinness, and can employ secondary batteries as their power source.

[0173] Example Examples of the present application are described below. The examples described below are illustrative and are intended merely to interpret the present application and should not be understood as limiting the present application. If specific techniques or conditions are not specified in the examples, they are performed according to the techniques or conditions described in the literature in the field or according to the product specifications. If the manufacturers of the reagents or equipment used are not specified, they are all conventional products that are commercially available.

[0174] 1. Manufacturing method Example 1 1) Preparation of Non-Newtonian Fluid Electrolyte Composition In a dry argon atmosphere, polyethylene oxide (PEO, weight-average molecular weight 600,000), fumed silica, sodium bis(fluorosulfonyl)imide (NaFSI), and an ionic liquid of N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide were mixed in a mass ratio of 5:2:3:10 and stirred uniformly until the NaFSI was completely dissolved, yielding a non-Newtonian fluid electrolyte composition.

[0175] 2) Manufacturing of positive electrode plates Na4Fe3(PO4)2P2O7 (NFPP) material, conductive carbon black, and binder polyvinylidene fluoride were uniformly mixed with N-methylpyrrolidone (NMP) in a weight ratio of 8:1:1 to obtain a positive electrode slurry. The positive electrode slurry was then uniformly applied to the surface of the aluminum foil positive electrode current collector, followed by baking, cold pressing, and cutting to obtain a positive electrode plate.

[0176] 3) Manufacturing of negative electrode plates Carbon nanotubes and hydroxymethyl cellulose (CMC) were mixed in deionized water in a mass ratio of 1:0.4 and stirred to form a uniform slurry. The slurry was then applied to the copper foil of the negative electrode current collector, baked, and cut to obtain a negative electrode plate with a negative electrode-free structure. The surface density of the undercoat layer was 10 g / m. 2 and the thickness of the undercoat layer is 5 μm.

[0177] 4) Separator A polypropylene film was used as a separator.

[0178] 5) Battery manufacturing The non-Newtonian fluid electrolyte composition was cast onto both sides of the separator, and then a positive electrode plate, the separator coated with the non-Newtonian fluid electrolyte composition, and a negative electrode plate were stacked in this order, with the separator positioned between the positive and negative electrodes to serve as an insulator, and then wound up to obtain a bare cell. Tabs were welded to the bare cell, and the bare cell was then packed into an aluminum case and baked at 80°C to remove moisture, resulting in an uncharged battery. The uncharged battery was then subjected to subsequent processes such as standing, hot pressing, cold pressing, chemical formation, shaping, and capacity testing, resulting in the negative electrode-free sodium battery product of Example 1.

[0179] Examples 2 to 4 The batteries of Examples 2 to 4 were manufactured using a method similar to that of Example 1, but the type of sodium salt was adjusted.

[0180] Examples 5-6 The batteries of Examples 5 and 6 were manufactured using a method similar to that of Example 1, but the type of ionic liquid was adjusted.

[0181] Examples 7-8 The batteries of Examples 7 and 8 were manufactured using a method similar to that of Example 1, but the type of polymer was adjusted.

[0182] Example 9 The battery of Example 9 was manufactured in a similar manner to that of Example 1, but the manufacturing method of the non-Newtonian fluid electrolyte composition was adjusted, and the specific manufacturing method was as follows:

[0183] In a dry argon atmosphere, polyethylene oxide (PEO, weight-average molecular weight 600,000), polyethylene glycol (PEG, weight-average molecular weight 10,000), sodium bis(fluorosulfonyl)imide (NaFSI), and an ionic liquid of N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide were mixed in a mass ratio of 5:2:3:10 and stirred until the NaFSI was completely dissolved, yielding a non-Newtonian fluid electrolyte composition.

[0184] Examples 10 to 13 The batteries of Examples 10 to 13 were manufactured using a method similar to that of Example 1, but the types of suspended particles were adjusted.

[0185] Example 14 The battery of Example 14 was fabricated using a method similar to that of Example 1, but with the mass contents of sodium salt, ionic liquid, polymer and suspended particles adjusted. The specific parameters are as shown in Table 1.

[0186] Example 15 The battery of Example 15 was manufactured in a similar manner to that of Example 1, but the manufacturing method of the non-Newtonian fluid electrolyte composition was adjusted, and the specific manufacturing method was as follows:

[0187] In a dry argon atmosphere, fumed silica, sodium bis(fluorosulfonyl)imide (NaFSI), and an ionic liquid of N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide were mixed in a mass ratio of 1:1:3, stirred uniformly until the NaFSI was completely dissolved, and then cooled to room temperature to obtain a non-Newtonian fluid electrolyte composition.

[0188] Examples 16-17 The batteries of Examples 16 and 17 were manufactured using a method similar to that of Example 15, but the types of ionic liquid and suspended particles were adjusted accordingly.

[0189] Example 18 The battery of Example 18 was manufactured in a similar manner to that of Example 1, but the manufacturing method of the non-Newtonian fluid electrolyte composition was adjusted, and the specific manufacturing method was as follows:

[0190] In a dry argon atmosphere, polyethylene oxide (PEO, weight-average molecular weight 600,000), fumed silica, sodium bis(fluorosulfonyl)imide (NaFSI), and an organic solvent, ethylene glycol dimethyl ether (DME), were mixed in a mass ratio of 5:2:3:10 and stirred uniformly until the NaFSI was completely dissolved, yielding a non-Newtonian fluid electrolyte composition.

[0191] Examples 19-20 The batteries of Examples 19 and 20 were manufactured using a method similar to that of Example 18, but the type of organic solvent was adjusted.

[0192] Example 21 The battery of Example 21 was prepared in a similar manner to that of Example 18, except that the mass contents of sodium salt, organic solvent, polymer and suspended particles were adjusted. The specific parameters are as shown in Table 1.

[0193] Example 22 The battery of Example 22 is manufactured in a similar manner to that of Example 18, but the manufacturing method of the non-Newtonian fluid electrolyte composition is adjusted, and the specific manufacturing method is as follows:

[0194] In a dry argon atmosphere, fumed silica, sodium bis(fluorosulfonyl)imide (NaFSI), and an organic solvent, ethylene glycol dimethyl ether (DME), were mixed in a mass ratio of 1:1:3, stirred uniformly until the NaFSI was completely dissolved, and then cooled to room temperature to obtain a non-Newtonian fluid electrolyte composition.

[0195] Examples 23-24 The batteries of Examples 23 and 24 were manufactured using a method similar to that of Example 22, but the types of organic solvent and suspended particles were adjusted.

[0196] Examples 25-26 The batteries of Examples 25 and 26 were manufactured using a method similar to that of Example 1, but the type of positive electrode active material was adjusted. The specific parameters were as shown in Table 1, and the thickness of the ZrO2 coating layer in Example 26 was 30 nm.

[0197] Examples 27 to 33 The batteries of Examples 27 to 33 were manufactured using a method similar to that of Example 1, but with the mass contents of sodium salt, ionic liquid, polymer and suspended particles adjusted. The specific parameters are as shown in Table 1.

[0198] Comparative Example 1 The battery of Comparative Example 1 was manufactured using a method similar to that of Example 1, but the method for manufacturing the electrolyte was adjusted, and the specific manufacturing method was as follows.

[0199] In a dry argon atmosphere, polyethylene oxide (PEO, weight-average molecular weight 600,000), sodium bis(fluorosulfonyl)imide (NaFSI), and the organic solvent ethylene glycol dimethyl ether (DME) were mixed in a mass ratio of 7:3:10, stirred uniformly to completely dissolve the NaFSI, and then cooled to room temperature to obtain a quasi-solid electrolyte.

[0200] Comparative Example 2 The battery of Comparative Example 2 was manufactured in a similar manner to that of Comparative Example 1, except that the mass contents of the sodium salt, organic solvent and polymer were adjusted. The specific parameters are as shown in Table 1.

[0201] Comparative Examples 3 to 5 The batteries of Comparative Examples 3 to 5 were manufactured using a method similar to that of Comparative Example 1, but the type of sodium salt was adjusted.

[0202] Comparative Example 6 The battery of Example 6 was manufactured in a similar manner to that of Comparative Example 1, but the type of solvent was adjusted. The specific parameters are as shown in Table 1.

[0203] Comparative Examples 7 to 9 The batteries of Examples 7 to 9 were manufactured using a method similar to that of Comparative Example 1, but the liquid electrolyte was used and the type of positive electrode material was adjusted, as shown in Table 1. The thickness of the ZrO2 coating layer in Comparative Example 9 was 30 nm.

[0204] 2. Performance test 1. Performance test of non-Newtonian fluid electrolyte composition 1) Viscosity test The non-Newtonian fluid electrolyte compositions were tested using a Dveslvtjo rotational viscosity tester (BROOKFIELD) for 10 seconds and 10 minutes while rotating, and the viscosity values ​​were recorded. The test conditions were 25°C, 12 rpm, and a 64# rotor was used to measure viscosities of 2000 mPa·s or more, and a 62# rotor was used to measure viscosities below 2000 mPa·s. Three parallel measurements were performed, and the average value was calculated.

[0205] 2) Loss factor test The test instrument is a Haake rheometer. The non-Newtonian fluid electrolyte composition sample is cut into a disk shape with a diameter of 20 mm and a thickness of 1 mm. The test temperature is 25°C, the strain sweep range is 0.1% to 1000%, and the fixed frequency is 1 Hz. The storage modulus (G') and loss modulus (G") are obtained, respectively. The formula for TIFF2025535385000004.tif6170 is The file is TIFF2025535385000005.tif6150.

[0206] 3) Nail penetration strength test Single-layer foil or pouch batteries based on a combination of non-Newtonian fluid electrolytes were fabricated and assembled, then fixed to a test jig. A tensile tester and nail penetration jig manufactured by Kaotie Co. were used. A 1 mm diameter nail was used in the nail penetration tester, and the nail was penetrated at a rate of 6 mm / min. When the nail penetration depth reached 2 mm, the test was stopped and the battery was allowed to stand. The change in open circuit voltage was observed, and the time required for the open circuit voltage to drop to 2 mV was recorded.

[0207] 4) Pressurization strength test A semi-cylindrical pressure plate with a radius of 75 mm was placed perpendicular to the direction of the battery's electrodes, and the pressure speed was set to 60 mm / min. The changes in the battery's open circuit voltage and the pressure applied by the pressure plate were observed, and the pressure applied by the pressure plate when the open circuit voltage was zero was recorded.

[0208] 2. Battery performance test 1) Coulombic efficiency test The Coulombic efficiency test was carried out as follows: At 25°C, the fabricated battery was charged at a constant current of 0.1 C to 3.7 V (sodium iron pyrophosphate cathode) or 4.0 V (layered oxide cathode), and then charged at a constant voltage of 3.7 V until the current dropped to 0.01 C to obtain the initial charge capacity (Cc1). It was then discharged at a constant current of 0.1 C to 2.5 V to obtain the initial discharge capacity (Cd1). After performing n charge and discharge cycles, the number of cycles n at which the capacity was reduced to 80% was recorded, and the average Coulombic efficiency of the battery was calculated according to the following formula: Coulombic efficiency of each cycle = Discharge capacity of this cycle (Cd1) / Charge capacity of this cycle (Cc1) × 100% The average value of the coulombic efficiency from the second cycle to the nth cycle was taken as the average coulombic efficiency of the battery.

[0209] The test process for the comparative example and other examples is as described above.

[0210] 2) Testing the number of cycles required to reach 80% capacity retention The cycle count test procedure for reaching 80% capacity retention was as follows: At 25°C, the fabricated battery was charged at a constant current of 1 C to 3.7 V (sodium iron pyrophosphate cathode) or 4.0 V (layered oxide cathode), followed by charging at a constant voltage of 3.7 V until the current dropped to 0.1 C. The battery was then discharged at 1 C to 2.5 V, and the resulting capacity was recorded as the initial capacity (C0). The same battery was repeated, and the discharge capacity (Cn) of the battery after n cycles was simultaneously recorded. The battery capacity retention rate after each cycle, Pn, was calculated as Cn / C0 × 100%, and the number of cycles when Pn dropped to 80% was recorded. The test procedures for the comparative example and other examples were as described above.

[0211] 3) Cycle gas generation performance test The cycle gas generation performance test process is as follows: The initial charge and discharge are performed at 25°C. Constant-current and constant-voltage charging is performed at a charge current of 1C until the upper voltage reaches approximately 3.7V (sodium iron pyrophosphate cathode) or 4.0V (layered oxide cathode). Subsequently, constant-current discharging is performed at a discharge current of 1C until the final voltage reaches approximately 2.5V. The thickness D1 of the battery at this time is recorded. The charge and discharge cycle is then repeated n times. The number of cycles n at which the capacity decays to 80% and the thickness Dn after n cycles are recorded. Gas generation performance: the expansion rate at which the capacity retention rate reaches 80% = (Dn - D1) / D1 × 100%. The test process for the comparative example and other examples is as described above.

[0212] 4) Stacking pressure test The stack pressure test process is as follows: A constant pressure F is applied to the surface of the battery using a battery fixture. This pressure is controlled by adjusting the magnitude of the pressure applied to the battery fixture using a punching machine and by adjusting the screws on the battery fixture, and the specific value is output by a pressure sensor built into the battery. An AC impedance test using an electrochemical workstation can be performed to obtain the impedance R, which represents the sum of the ohmic resistance and interfacial resistance of the electrolyte. An impedance-pressure curve is obtained with pressure as the abscissa and impedance as the ordinate, and the F value at which the impedance R value is smallest is recorded.

[0213] 3. Analysis of the test results of each example and comparative example Batteries of each example and comparative example were manufactured by the above method, and performance parameters were measured. The results are shown in Tables 1 to 3 below.

[0214] [Table 1-1] [Table 1-2] [Table 1-3]

Table 1-4

Table 1-5

Table 1-6

Table 1-7

Table 1-8

Table 1-9

Table 1-10

Table 1-11

[0215]

Table 2-1

Table 2-2

[0216] [Table 3-1] [Table 3-2]

[0217] As can be seen from the above results, for the non-Newtonian fluid electrolyte compositions of Examples 1 to 33, the viscosity of the non-Newtonian fluid electrolyte composition changes with the change in shear time due to the action of shear force. The sodium salt in the non-Newtonian fluid electrolyte composition is selected from sodium chloride, sodium hexafluorophosphate, sodium trifluoromethanesulfonate, or sodium bis(fluorosulfonyl)imide, and the ionic liquid in the non-Newtonian fluid electrolyte composition is selected from N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide, trihexyl(tetradecyl)phosphonium bis(trifluoromethanesulfonyl)imide. the organic solvent in the non-Newtonian fluid electrolyte composition is selected from ethylene glycol dimethyl ether, ethylene carbonate, or dimethyl sulfoxide; the polymer in the non-Newtonian fluid electrolyte composition is selected from one or two of polyethylene oxide, polyethylene glycol, and polyvinylpyrrolidone; and the suspended particles in the non-Newtonian fluid electrolyte composition are selected from fumed silica, sodium oxide, lithium oxide, polyurethane, or sodium fluoride.

[0218] As can be seen from a comparison between Examples 1 to 33 and Comparative Examples 1 to 6, compared with conventional electrolytes, the non-Newtonian fluid electrolyte compositions do not satisfy Newton's law of viscosity. After mechanical thixotropy, the loss factor of the non-Newtonian fluid electrolyte combinations decreases by more than 10% (loss factor decrease rate = (loss factor before mechanical thixotropy - loss factor after mechanical thixotropy) / loss factor before mechanical thixotropy × 100%), which contributes to increasing the compressive strength when the open circuit voltage becomes zero and reducing the stacking pressure when the ohmic resistance and interfacial resistance of the electrolyte are at their smallest, significantly improving the impact resistance of the battery and improving the battery assembly process.

[0219] As can be seen from the comparison between Example 14 and Example 15, and Example 21 and Example 22, the introduction of polyethylene oxide into the non-Newtonian fluid electrolyte composition contributes to increasing the number of cycles required for the battery's capacity retention rate to reach 80% and reducing the expansion rate when the capacity retention rate reaches 80%.

[0220] As can be seen from comparisons of Examples 1 and 18 with Comparative Example 1, Examples 14-15, 21-22 with Comparative Example 2, Example 2 with Comparative Example 3, Example 3 with Comparative Example 4, Example 4 with Comparative Example 5, and Example 19 with Comparative Example 6, when the sodium salt in the non-Newtonian fluid electrolyte composition is selected from sodium chloride, sodium hexafluorophosphate, sodium trifluoromethanesulfonate, or sodium bis(fluorosulfonyl)imide, the time until the open circuit voltage of the non-Newtonian fluid electrolyte composition drops to 2 mV after nail penetration and the compressive strength when the open circuit voltage becomes zero are increased, the number of cycles until the battery capacity retention rate reaches 80% is increased, and the expansion rate when the battery capacity retention rate reaches 80% and the stacking pressure when the ohmic resistance and interfacial resistance of the electrolyte are at their smallest are reduced. As can be seen from a comparison between Examples 1 and 3 and Examples 2 and 4, by controlling the selection of the sodium salt from sodium trifluoromethanesulfonate or sodium bis(fluorosulfonyl)imide, the rate of decline in the loss coefficient after mechanical thixotropy of the non-Newtonian fluid electrolyte composition is increased, further increasing the average coulombic efficiency of the battery and contributing to a significant increase in the number of cycles until the capacity retention rate reaches 80%.

[0221] As can be seen from a comparison of Examples 1, 5 to 6 with Comparative Example 1, and Examples 14 to 16 with Comparative Example 2, when the ionic liquid in the non-Newtonian fluid electrolyte composition is selected from N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide, trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide, or 1-alkyl-3-methylimidazolium tetrafluoroborate, the time until the open circuit voltage of the non-Newtonian fluid electrolyte composition drops to 2 mV after nail penetration and the pressing strength when the open circuit voltage becomes zero are increased, and the stacking pressure when the ohmic resistance and interfacial resistance of the electrolyte are minimized is reduced, contributing to an improvement in the battery assembly process. As can be seen from a comparison between Examples 1 and 5 and Example 6, and Example 15 and Example 16, by controlling the ionic liquid to be selected from N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide or trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide, the time until the open circuit voltage of the non-Newtonian fluid electrolyte composition drops to 2 mV after nail penetration and the compressive strength when the open circuit voltage becomes zero can be further increased, which contributes to a greater increase in the average coulombic efficiency of the battery and the number of cycles until the capacity retention rate reaches 80%, and significantly reduces the expansion rate when the battery capacity retention rate reaches 80% and the stacking pressure when the ohmic resistance and interfacial resistance of the electrolyte are at their lowest.

[0222] As can be seen from a comparison of Examples 1, 7 to 9 with Comparative Example 1, selecting one or two of polyethylene oxide, polyethylene glycol, and polyvinylpyrrolidone as the polymer in the non-Newtonian fluid electrolyte composition increases the time it takes for the open circuit voltage of the non-Newtonian fluid electrolyte composition to drop to 2 mV after nail penetration and the compressive strength when the open circuit voltage becomes zero, and contributes to reducing the expansion rate when the battery capacity retention rate reaches 80% and the stacking pressure when the electrolyte ohmic resistance and interfacial resistance are at their lowest. As can be seen from a comparison of Examples 1, 7, and 9 with Example 8, selecting one or two of polyethylene oxide and polyethylene glycol as the polymer further increases the average coulombic efficiency of the battery and the number of cycles until the capacity retention rate reaches 80%, and contributes to significantly reducing the stacking pressure when the electrolyte ohmic resistance and interfacial resistance are at their lowest.

[0223] As can be seen from a comparison of Examples 1, 10-13 with Comparative Example 1, and Examples 14-15, 17, 21-22, and 24 with Comparative Example 2, selecting the suspended particles in the non-Newtonian fluid electrolyte composition from fumed silica, sodium oxide, lithium oxide, polyurethane, or sodium fluoride increases the time it takes for the open-circuit voltage of the non-Newtonian fluid electrolyte composition to drop to 2 mV after nail penetration and the compressive strength when the open-circuit voltage becomes zero, and contributes to reducing the stacking pressure at which the ohmic resistance and interfacial resistance of the electrolyte are minimized. As can be seen from a comparison of Examples 1, 10-11 with Examples 12-13, selecting the suspended particles from fumed silica, sodium oxide, or lithium oxide further increases the average coulombic efficiency of the battery and the number of cycles required to reach 80% capacity retention, and contributes to significantly reducing the expansion rate when the battery capacity retention reaches 80%.

[0224] Comparisons of Examples 18 and 20 with Comparative Example 1, Examples 21 and 22 with Comparative Example 2, and Examples 19 and 23 with Comparative Example 6 reveal that selecting an organic solvent from ethylene glycol dimethyl ether, ethylene carbonate, or dimethyl sulfoxide in the non-Newtonian fluid electrolyte composition increases the time it takes for the open circuit voltage of the non-Newtonian fluid electrolyte composition to drop to 2 mV after nail penetration and the compressive strength when the open circuit voltage becomes zero, and contributes to reducing the stacking pressure at which the ohmic resistance and interfacial resistance of the electrolyte are minimized. Comparisons of Examples 18 with Examples 19 and 20, and Examples 22 and 23 reveal that selecting an organic solvent from ethylene glycol dimethyl ether further increases the time it takes for the open circuit voltage of the non-Newtonian fluid electrolyte composition to drop to 2 mV after nail penetration and the compressive strength when the open circuit voltage becomes zero, thereby significantly increasing the average coulombic efficiency and the number of cycles until the capacity retention rate of the battery reaches 80%, and contributing to a significant reduction in the expansion rate when the capacity retention rate of the battery reaches 80%.

[0225] As can be seen from a comparison of Examples 1 and 3 with Examples 2 and 4, Examples 1 and 5 with Example 6, Example 15 with Example 16, Examples 1, 8-9 with Example 7, Examples 1, 10-11 with Examples 12-13, Example 18 with Examples 19-20, and Example 22 with Example 23, the sodium salt is selected from sodium trifluoromethanesulfonate or sodium bis(fluorosulfonyl)imide, the ionic liquid is selected from N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide or trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide, the polymer is selected from one or two of polyethylene oxide and polyethylene glycol, the suspended particles are selected from fumed silica, sodium oxide, or lithium oxide, and the organic solvent is selected from ethylene glycol dimethyl ether, thereby further increasing the average coulombic efficiency and contributing to a significant increase in the number of cycles until the capacity retention rate reaches 80%.

[0226] As can be seen from a comparison of Examples 1, 3, 5, 7, 8 to 11 with Comparative Example 1, and Example 14 with Comparative Example 2, by controlling the sodium salt to be selected from sodium trifluoromethanesulfonate or sodium bis(fluorosulfonyl)imide, the ionic liquid to be selected from N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide or trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide, the polymer to be selected from one or two of polyethylene oxide and polyethylene glycol, and the suspended particles to be selected from fumed silica, sodium oxide, or lithium oxide, the time until the open circuit voltage of the non-Newtonian fluid electrolyte composition drops to 2 mV after nail penetration and the compression strength when the open circuit voltage becomes zero can be increased, and the stack pressure at which the ohmic resistance and interfacial resistance of the electrolyte are minimized can be reduced.

[0227] As can be seen from a comparison between Examples 1 and 3 and Examples 2 and 4, between Examples 1 and 5 and Example 6, between Examples 1, 8-9 and Example 7, and between Examples 1, 10-11 and Examples 12-13, controlling the sodium salt to be selected from sodium trifluoromethanesulfonate or sodium bis(fluorosulfonyl)imide, the ionic liquid to be selected from N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide or trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide, the polymer to be selected from one or two of polyethylene oxide and polyethylene glycol, and the suspended particles to be selected from fumed silica, sodium oxide, or lithium oxide contributes to further increasing the number of cycles until the average coulombic efficiency and capacity retention rate reach 80%.

[0228] As can be seen from a comparison between Examples 15 to 17 and Comparative Example 1, by controlling the sodium salt to be selected from sodium bis(fluorosulfonyl)imide, the ionic liquid to be selected from N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide or trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide, and the suspended particles to be selected from fumed silica or sodium oxide, the time until the open circuit voltage of the non-Newtonian fluid electrolyte composition drops to 2 mV after nail penetration and the compression strength when the open circuit voltage becomes zero can be increased, and the stack pressure at which the ohmic resistance and interfacial resistance of the electrolyte are minimized can be reduced.

[0229] As can be seen from a comparison between Example 18 and Comparative Example 1, and Example 21 and Comparative Example 2, by controlling the sodium salt to be selected from sodium bis(fluorosulfonyl)imide, the organic solvent to be selected from ethylene glycol dimethyl ether, the polymer to be selected from polyethylene oxide, and the suspended particles to be selected from fumed silica, the time until the open circuit voltage of the non-Newtonian fluid electrolyte composition drops to 2 mV after nail penetration and the compressive strength when the open circuit voltage becomes zero can be increased, and the average coulombic efficiency of the battery and the number of cycles until the capacity retention rate reaches 80% can be increased, and the expansion rate when the battery capacity retention rate reaches 80% and the stacking pressure when the ohmic resistance and interfacial resistance of the electrolyte are at their minimum can be reduced.

[0230] As can be seen from a comparison between Example 18 and Examples 19 to 20, by controlling the sodium salt to be selected from sodium bis(fluorosulfonyl)imide, the organic solvent to be selected from ethylene glycol dimethyl ether, the polymer to be selected from polyethylene oxide, and the suspended particles to be selected from fumed silica, the time until the open circuit voltage of the non-Newtonian fluid electrolyte composition drops to 2 mV after nail penetration and the compressive strength when the open circuit voltage becomes zero can be increased, which contributes to a greater increase in the average coulombic efficiency of the battery and the number of cycles until the capacity retention rate reaches 80%, and significantly reduces the expansion rate when the capacity retention rate of the battery reaches 80%.

[0231] As can be seen from a comparison between Examples 22 and 24 and Comparative Example 2, by controlling the sodium salt to be selected from sodium bis(fluorosulfonyl)imide, the organic solvent to be selected from ethylene glycol dimethyl ether, and the suspended particles to be selected from fumed silica or sodium oxide, the time until the open circuit voltage of the non-Newtonian fluid electrolyte composition drops to 2 mV after nail penetration and the compressive strength when the open circuit voltage becomes zero can be increased, the number of cycles until the battery capacity retention rate reaches 80% can be increased, and the expansion rate when the battery capacity retention rate reaches 80% and the stacking pressure when the ohmic resistance and interfacial resistance of the electrolyte are at their minimum can be reduced.

[0232] As can be seen from a comparison of Examples 22 and 24 with Example 23, by controlling the sodium salt to be selected from sodium bis(fluorosulfonyl)imide, the organic solvent to be selected from ethylene glycol dimethyl ether, and the suspended particles to be selected from fumed silica or sodium oxide, the compressive strength of the non-Newtonian fluid electrolyte composition when the open circuit voltage becomes zero can be further increased, which contributes to a greater increase in the average coulombic efficiency of the battery and the number of cycles until the capacity retention rate reaches 80%, and to a significant decrease in the expansion rate when the battery capacity retention rate reaches 80% and the stacking pressure when the ohmic resistance and interfacial resistance of the electrolyte are at their lowest.

[0233] As can be seen from the comparison between Example 1 and Examples 25 to 26, Na(Cu 1 / 9 Ni 2 / 9 Fe 1 / 3 Mn 1 / 3 ) Na coated with O2, ZrO2, TiO2 2 / 3 Ni 1 / 6 Mn 2 / 3 Cu 1 / 9 Mg 1 / 18Compared to using O2 as the positive electrode active material, using Na4Fe3(PO4)2P2O7 as the positive electrode active material increases the number of cycles until the battery's average coulombic efficiency and capacity retention rate reach 80%, and further contributes to significantly reducing the expansion rate when the battery's capacity retention rate reaches 80% and the stacking pressure when the electrolyte's ohmic resistance and interfacial resistance are at their lowest.

[0234] As can be seen from the comparison between Example 25 and Example 26, Na(Cu 1 / 9 Ni 2 / 9 Fe 1 / 3 Mn 1 / 3 ) Compared to using O2 as the positive electrode active material, Na coated with ZrO2 and TiO2 2 / 3 Ni 1 / 6 Mn 2 / 3 Cu 1 / 9 Mg 1 / 18 The use of O2 as the positive electrode active material increases the number of cycles required for the battery's average coulombic efficiency and capacity retention rate to reach 80%, and also contributes to significantly reducing the expansion rate when the battery's capacity retention rate reaches 80%.

[0235] As can be seen from the comparison between Examples 14 and 21, and between Examples 15 and 22, compared to the non-Newtonian fluid electrolyte containing an ethylene glycol dimethyl ether organic solvent, the non-Newtonian fluid electrolyte containing an ionic liquid of N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide has better performance, increasing the time until the open circuit voltage of the non-Newtonian fluid electrolyte composition drops to 2mV after nail penetration and the compressive strength when the open circuit voltage becomes zero, as well as increasing the number of cycles until the battery capacity retention rate reaches 80%, and contributing to reducing the stacking pressure at which the ohmic resistance and interfacial resistance of the electrolyte are at their lowest.

[0236] As can be seen from a comparison of Examples 1 and 27 to 34 with Comparative Example 1, the mass content of the electrolyte salt is 5% to 20%, the mass content of the ionic liquid is 20% to 60%, the mass content of the polymer is 0% to 40%, and the mass content of the suspended particles is greater than 0 and less than 20%, based on the total mass of the non-Newtonian fluid electrolyte composition. This increases the time it takes for the open circuit voltage of the non-Newtonian fluid electrolyte composition to drop to 2mV after nail penetration and the compressive strength when the open circuit voltage becomes zero, increases the average coulombic efficiency of the battery and the number of cycles until the capacity retention rate reaches 80%, and contributes to reducing the expansion rate when the battery capacity retention rate reaches 80% and the stacking pressure when the ohmic resistance and interfacial resistance of the electrolyte are at their lowest.

[0237] As can be seen from a comparison of Examples 18, 25-26 and Comparative Examples 7-9, the non-Newtonian fluid electrolyte composition can be applied to a variety of different positive electrode materials, and compared to batteries using liquid electrolytes with similar compositions, the high viscosity can effectively suppress gas generation in the battery, further improving the cycle performance of the battery, and in particular the cycle performance at high voltage of the positive electrode layered oxide can be effectively improved.

[0238] It should be noted that the present application is not limited to the above-described embodiments. The above-described embodiments are merely examples, and all embodiments that have substantially the same configuration as the technical idea and exhibit the same functions and effects within the scope of the technical solution of the present application are encompassed within the technical scope of the present application. Furthermore, various modifications that can be conceived by a person skilled in the art to the embodiments and other forms configured by combining some of the components of the embodiments are also encompassed within the scope of the present application, as long as they do not deviate from the gist of the present application. [Explanation of symbols]

[0239] 1 battery pack 2 Upper Box 3 Lower Box 4 Battery Module 5 Secondary battery 51 cases 52 Electrode assembly 53 Cover plate

Claims

1. An electrolyte composition characterized in that it is a non-Newtonian fluid electrolyte composition.

2. 2. The electrolyte composition according to claim 1, wherein the viscosity of the electrolyte composition is 1,000 mPa·s to 50,000 mPa·s after stirring the electrolyte composition for 10 seconds while rotating at 25°C with a 62# or 64# rotor of a Dveslvtjo rotational viscosity tester at a speed of 12 rpm.

3. 2. The electrolyte composition of claim 1, wherein after stirring the electrolyte composition for 10 minutes while rotating at 25°C with a 62# or 64# rotor of a Dveslvtjo rotational viscosity tester at a speed of 12 rpm, the viscosity of the electrolyte composition increases by more than 100 mPa s compared to the viscosity after testing for 10 seconds under the same conditions.

4. The electrolyte composition according to any one of claims 1 to 3, characterized in that the non-Newtonian fluid electrolyte composition has a loss factor after mechanical thixotropy that decreases by more than 10% relative to the loss factor before mechanical thixotropy.

5. 4. The electrolyte composition according to claim 1, wherein the non-Newtonian fluid electrolyte composition comprises one of an organic solvent and an ionic liquid, an electrolyte salt, and suspended particles.

6. 6. The electrolyte composition according to claim 1, wherein the non-Newtonian fluid electrolyte composition further comprises a polymer.

7. 7. The electrolyte composition of claim 5, wherein the electrolyte salt comprises a sodium salt, and the sodium salt comprises one or more of sodium chloride, sodium bromide, sodium nitrate, sodium perchlorate, sodium hexafluorophosphate, sodium acetate, sodium trifluoroacetate, sodium trifluoromethanesulfonate, sodium bis(fluorosulfonyl)imide, and sodium bis(trifluoromethanesulfonyl)imide, and optionally one or more of sodium trifluoromethanesulfonate, sodium bis(fluorosulfonyl)imide, and sodium bis(trifluoromethanesulfonyl)imide.

8. The electrolyte composition according to any one of claims 5 to 7, wherein the organic solvent comprises one or more of an ether organic solvent, an ester organic solvent, and a sulfur-containing organic solvent, and further comprises one or more of ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, ethylene carbonate, propylene carbonate, butylene carbonate, vinylene carbonate, fluoroethylene carbonate, ethyl methyl carbonate, dimethyl carbonate, diethyl carbonate, dipropyl carbonate, and dimethyl sulfoxide, and optionally comprises ethylene glycol dimethyl ether.

9. The electrolyte composition according to any one of claims 5 to 8, wherein the ionic liquid comprises one or more of 1-butyl-3-methylimidazolium chloride, 1-alkyl-3-methylimidazolium tetrafluoroborate, N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide, 5-azoniaspiro[4,4]nonane hexafluorophosphate, trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide, and tetrabutylphosphonium hexafluorophosphate, and optionally comprises one or more of N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide and trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide.

10. The electrolyte composition according to any one of claims 6 to 9, characterized in that the polymer comprises polyethylene oxide, polyethylene glycol, polyvinylpyrrolidone, polymethyl methacrylate, polyvinylidene fluoride, polyvinyl alcohol, and polyacrylamide, and optionally contains one or more of polyethylene oxide and polyethylene glycol.

11. 11. The electrolyte composition of any one of claims 5 to 10, wherein the suspended particles comprise one or more of fumed silica, aluminum oxide, sodium oxide, lithium oxide, sodium fluoride, lithium fluoride, polyurethane, and optionally one or more of fumed silica, sodium oxide, and lithium oxide.

12. 12. The electrolyte composition of claim 5, wherein the electrolyte salt comprises one or more of sodium trifluoromethanesulfonate, sodium bis(fluorosulfonyl)imide, and sodium bis(trifluoromethanesulfonyl)imide; the organic solvent comprises ethylene glycol dimethyl ether; the ionic liquid comprises one or more of N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide and trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide; the polymer comprises one or more of polyethylene oxide and polyethylene glycol; and the suspended particles comprise one or more of fumed silica, sodium oxide, and lithium oxide.

13. 13. The electrolyte composition of claim 5, wherein the electrolyte salt comprises one or more of sodium trifluoromethanesulfonate, sodium bis(fluorosulfonyl)imide, and sodium bis(trifluoromethanesulfonyl)imide; the organic solvent comprises ethylene glycol dimethyl ether; and the suspended particles comprise one or more of fumed silica, sodium oxide, and lithium oxide.

14. 13. The electrolyte composition of claim 6, wherein the electrolyte salt comprises one or more of sodium trifluoromethanesulfonate, sodium bis(fluorosulfonyl)imide, and sodium bis(trifluoromethanesulfonyl)imide; the organic solvent comprises ethylene glycol dimethyl ether; the polymer comprises one or more of polyethylene oxide and polyethylene glycol; and the suspended particles comprise one or more of fumed silica, sodium oxide, and lithium oxide.

15. 13. The electrolyte composition of claim 5, wherein the electrolyte salt comprises one or more of sodium trifluoromethanesulfonate, sodium bis(fluorosulfonyl)imide, and sodium bis(trifluoromethanesulfonyl)imide; the ionic liquid comprises one or more of N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide and trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide; and the suspended particles comprise one or more of fumed silica, sodium oxide, and lithium oxide.

16. 13. The electrolyte composition of claim 6, wherein the electrolyte salt comprises one or more of sodium trifluoromethanesulfonate, sodium bis(fluorosulfonyl)imide, and sodium bis(trifluoromethanesulfonyl)imide; the ionic liquid comprises one or more of N-alkyl-N-methylpiperidine bistrifluoromethanesulfonimide and trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)imide; the polymer comprises one or more of polyethylene oxide and polyethylene glycol; and the suspended particles comprise one or more of fumed silica, sodium oxide, and lithium oxide.

17. 17. The electrolyte composition according to claim 6, wherein, based on the total mass of the non-Newtonian fluid electrolyte composition, the mass content of the electrolyte salt is 5% to 20%, the mass content of the organic solvent is 20% to 60%, the mass content of the ionic liquid is 20% to 60%, the mass content of the polymer is 0% to 40%, and the mass content of the suspended particles is greater than 0 and equal to or less than 20%.

18. 18. The electrolyte composition according to claim 1, wherein the non-Newtonian fluid electrolyte composition has a compressive strength of 35 kN to 200 kN.

19. A secondary battery comprising a positive electrode plate and the electrolyte composition according to any one of claims 1 to 18.

20. 20. The secondary battery of claim 19, wherein the secondary battery is a sodium metal battery.

21. 21. The secondary battery according to claim 19, wherein the secondary battery is a negative electrode free sodium battery.

22. 22. The secondary battery according to claim 19, wherein the positive electrode plate includes a positive electrode active material, the positive electrode active material including at least one of a transition metal layered oxide, a polyanion compound, and a Prussian blue compound, and the positive electrode active material includes one or more of NaNiFeMnO, Na(CuNiFeMn)O, NaNiMnCuMgO, NaFe(PO),P, NaFePO, NaV(PO), NaCoFe(CN), NaNiFe(CN), and NaMnFe(CN).

23. 23. The secondary battery of claim 22, further comprising a coating layer on a surface of the positive electrode active material, the coating layer including one or more of a carbon material, ZrO2, TiO2, polyaniline, polypyrrole, poly(3,4-ethylenedioxythiophene), aluminum oxide, zinc oxide, titanium oxide, zirconium oxide, magnesium oxide, silicon oxide, lanthanum oxide, sodium fluoride, lithium fluoride, and aluminum fluoride, and the carbon material including one or more of amorphous carbon, graphite, and graphene.

24. A battery module comprising the secondary battery according to any one of claims 19 to 23.

25. A battery pack comprising the secondary battery according to any one of claims 19 to 23 or the battery module according to claim 24.

26. A power consumption device comprising at least one of the secondary battery according to any one of claims 19 to 23, the battery module according to claim 24, and the battery pack according to claim 25.

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