53 results about "Lithium hexafluorophosphate" patented technology

This invention proposes a lithium-ion battery electrolyte and its application. The electrolyte comprises at least the following components: a fluorinated solvent, including 2,2-difluoroethyl acetate, fluoroethylene carbonate, and 2,2-difluoroethyl ethyl carbonate; a lithium salt, including a first lithium salt comprising lithium hexafluorophosphate; and an additive, including a first additive comprising lithium difluorobis(oxalato)phosphate. The lithium-ion battery electrolyte and its application proposed in this invention can improve the electrolyte's high-voltage resistance and kinetic performance, reduce battery impedance, and enhance the battery's fast-charging performance and high-temperature cycle stability.

This invention relates to a wide-temperature-range, high-power, low-temperature charge-discharge-cycle-capable starting lithium-ion battery. The invention comprises a positive electrode, a negative electrode, and an electrolyte, characterized in that: the positive electrode is composed of a lithium iron phosphate material body, a conductive agent, carbon nanotubes, a binder, and aluminum foil; the lithium iron phosphate material body is composed of lithium iron phosphate, titanium, and highly conductive carbon; the content of highly conductive carbon is 1.3–2.0%; the negative electrode is composed of artificial graphite, a conductive agent, sodium carboxymethyl cellulose, a binder, and copper foil, with 91–93 parts of artificial graphite, 2–5 parts of conductive agent, 0.5–1.5 parts of sodium carboxymethyl cellulose, and 2–3 parts of binder; the electrolyte is composed of lithium hexafluorophosphate, lithium salt additives, film-forming additives, and a low-melting-point solvent, with the concentration of lithium hexafluorophosphate being above 1.3 mol / L, lithium salt additives being 0.5–9 parts, and film-forming additives being 0.2–3 parts. This invention expands the operating temperature range of lithium-ion batteries to -40℃ to 65℃.

The application provides a silicon composite negative electrode material and a preparation method thereof, and relates to the technical field of lithium ion battery electrode materials. The method comprises the following steps: vacuum thermal reduction of graphene oxide to obtain graphene nanosheets; mixing of a strong acid and a silicon-based material, while adding the graphene nanosheets, stirring for 5min-60min, and then filtering and washing the turbid liquid to obtain a precipitate; adding lithium hexafluorophosphate into an organic solvent, placing the organic solvent in a sealed container, adding the precipitate and aluminum oxide at 60-180 DEG C, and reacting for 2-10h, and then drying to obtain the silicon composite negative electrode material. The silicon composite negative electrode material has high initial coulomb efficiency and good cycle stability.

A lithium-ion battery and an electric device. The lithium-ion battery comprises a positive electrode sheet and an electrolyte. An active material in the positive electrode sheet comprises a lithium phosphate positive electrode material and lithium nickel cobalt manganese oxide. The electrolyte comprises a positive electrode film-forming agent, a negative electrode film-forming agent and a lithium salt, wherein the lithium salt includes lithium hexafluorophosphate and lithium bisfluorosulfonylimide. The lithium-ion battery satisfies the following equation: 0.1≤(I)≤0.59, where NL is the mass ratio of lithium nickel cobalt manganese oxide to the lithium phosphate positive electrode material, Salt is the numerical value of the sum of the molar concentrations of lithium hexafluorophosphate and lithium bisfluorosulfonylimide in the electrolyte with the unit being mol / L, and Add is the mass ratio of the positive electrode film-forming agent to the negative electrode film-forming agent.

The embodiment of the application discloses a battery monomer, a battery device and a power utilization equipment. The battery monomer comprises: a shell, the shell comprising a shell body, a positive electrode end cover assembly and a negative electrode end cover assembly; an electrode assembly, the electrode assembly comprising a positive electrode sheet and a negative electrode sheet, and the electrode assembly is a laminated structure; the electrode assembly comprises a main body part and a tab part located at an end face of the main body part, and a size of the main body part in a first direction is greater than 400 mm; a single surface area density of a positive electrode film layer of the positive electrode sheet is greater than 375 mg / 1540.25 mm 2 ; an electrolyte, the electrolyte comprising a lithium salt and an additive; the lithium salt comprising at least one of lithium hexafluorophosphate and lithium bisfluorosulfonylimide; the additive comprising at least one of vinylene carbonate and a silane additive; and a mass content of the lithium salt is 14% to 20% and a mass content of the additive is 2% to 5% based on a total mass of the electrolyte. The battery monomer provided by the application considers both high energy density and fast charging long service life.

The application belongs to the field of lithium hexafluorophosphate production, in particular to a vacuum reaction furnace for lithium hexafluorophosphate production, which comprises a horizontal vacuum furnace, the inside of the horizontal vacuum furnace is provided with a rotatable inner stirring frame, the inner stirring frame is attached to the inner wall of the horizontal vacuum furnace, and a feeding door for feeding and discharging is installed on the top of the horizontal vacuum furnace. Through such a setting, an integrated preparation process of lithium hexafluorophosphate synthesis and purification reaction is realized, air and moisture pollution caused by raw material transfer during the synthesis and purification reaction process is eliminated, the post-processing process is increased, the quality is reduced, and other problems are solved. At the same time, the switchable negative pressure absorption system makes the treatment of the purification and synthesis stages adapt smoothly, realizes the possibility of common operation, reduces the transfer, post-processing and other process steps, and improves the production efficiency.

This invention relates to a crystallization apparatus for preparing lithium hexafluorophosphate, comprising: a tank body, a feeding device provided on the top surface of the tank body, and an array of heat exchange components provided on the inner wall of the tank body. The heat exchange components include several heat exchange plates disposed on the inner wall of the tank body and arranged along the length of the tank body. This apparatus can increase the heat exchange area and enhance the heat exchange efficiency, enabling the uniform and rapid precipitation of lithium hexafluorophosphate crystals, and achieving continuous production with simultaneous crystallization and scale prevention.

This invention relates to a non-flammable and safe electrolyte for high-voltage positive / silicon-carbon negative lithium-ion batteries and the lithium-ion battery itself. The electrolyte comprises a main solvent, a lithium salt, a flame retardant, and additives; the main solvent comprises fluoroethylene carbonate and linear carbonates or linear carboxylic acids. The lithium salt is lithium hexafluorophosphate. The flame retardant is (ethoxy)pentafluorocyclotriphosphazene. The concentration of the lithium salt in the electrolyte is 0.8–1.6 mol·L⁻¹. ‑1 The flame retardant has a mass percentage content of 1-10%, and each additive has a mass percentage content of 1-5%. The lithium-ion battery includes a positive electrode, a negative electrode, and a high-voltage positive electrode / silicon-carbon negative electrode. The lithium-ion battery uses a non-flammable and safe electrolyte. Compared with existing technologies, this invention has advantages such as being non-flammable, having good safety, high conductivity, good oxidation stability, compatibility with silicon-carbon negative electrodes, and promising application prospects.

The application relates to the lithium hexafluorophosphate preparation technical field, and particularly discloses a lithium hexafluorophosphate continuous dynamic crystallization equipment which comprises a first-stage crystallization kettle, a second-stage crystallization kettle, a third-stage crystallization kettle and more than one fourth-stage crystallization kettle, the first-stage crystallization kettle, the second-stage crystallization kettle, the third-stage crystallization kettle and the more than one fourth-stage crystallization kettle are arranged in a ladder shape at equal intervals, a material conveying pump is connected between adjacent crystallization kettles and after the fourth-stage crystallization kettle, and a stirring device is arranged in each crystallization kettle. Different crystallization stages are separated and carried out in different crystallization kettles, the crystallization kettles carrying out different crystallization stages are connected in a ladder shape, the crystallization process realizes continuous feeding and continuous discharging, the material flow between the crystallization kettles arranged in a ladder shape can be assisted by gravity to realize self-flow, so that stirring energy consumption is saved, and the multiple crystallization kettles arranged in a ladder shape can save the floor area.

An electrolyte, a battery cell, and a vehicle with a vehicle battery is provided. The electrolyte includes a ternary salt, dual-cyclic solvents, a linear carbonate solvent, and quaternary additives. The ternary salt includes lithium hexafluorophosphate (LiPF6), lithium bis(fluorosulfonyl)imide (LiFSI), and lithium difluoro(oxalate)borate (LiDFOB). The dual-cyclic solvents include ethylene carbonate (EC) between 0-30% by volume and fluoroethylene carbonate (FEC) between 0-30% by volume. The linear carbonate solvent includes at least one of ethyl methyl carbonate (EMC), dimethyl carbonate (DMC), or diethyl carbonate (DEC). The linear carbonate solvent is between 60-80% by volume. The quaternary additives include vinylene carbonate (VC) between 0.5-2% by weight, trimethylsilyl (TMSi) between 0.25-1% by weight, bis(2,2,2-trifluoroethyl) carbonate (DFDEC) between 0.5-2% by weight, and succinic anhydride (SA) between 0.25-1% by weight.

Disclosed in the present application is a method for preparing lithium hexafluorophosphate. According to the embodiments of the present application, the method comprises: performing mixing treatment on phosphorus pentafluoride gas and a lithium fluoride solution to give a first treatment product; and performing reaction treatment on the first treatment product to give a reaction solution containing lithium hexafluorophosphate, wherein the mixing treatment is performed in a first continuous flow reactor, and the reaction treatment is performed in a second continuous flow reactor. The method of the present application overcomes the defects in existing batch production techniques and effectively avoids the ineffective operation time of the start and end stages in conventional production, thereby improving the production efficiency and output per unit time.

This invention discloses a sulfide-based fluorine-free high-entropy electrolyte in the field of battery technology, comprising a composite lithium salt system, a sulfide solvent, and a fluorine-free inert diluent. The composite lithium salt system consists of at least two lithium salts selected from lithium hexafluorophosphate, lithium tetrafluoroborate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium difluorooxalate borate, lithium nitrate, lithium perchlorate, lithium trifluoromethanesulfonate, lithium trifluoroacetate, and lithium dioxalate borate. The sulfide solvent is selected from one or more of dimethyl sulfide, diethyl sulfide, methyl ethyl sulfide, methyl propyl sulfide, methyl butyl sulfide, dimethyl disulfide, cyclohexane sulfide, phenyl sulfide, and diphenyl disulfide. The fluorine-free inert diluent is at least one of cyclopentane, cyclohexane, n-hexane, benzene, n-butane, isobutane, and n-pentane. This invention solves the problems of existing electrolytes, such as difficulty in balancing conductivity and interfacial stability, poor high and low temperature performance, and narrow electrochemical window; and achieves a comprehensive improvement in the overall performance of the electrolyte.

The application discloses a method for producing phosphorus pentafluoride by electrolysis. The method is to use white phosphorus and anhydrous hydrogen fluoride as raw materials, fluorometal salt or quaternary ammonium fluoride salt as conductive agent, and to carry out electrolysis reaction in a high-nickel anode electrolysis container to produce phosphorus pentafluoride. The preparation method can produce high-purity phosphorus pentafluoride in one step, and the impurities are few when used for synthesizing lithium hexafluorophosphate, and no additional hydrogen chloride gas is produced, the post-processing cost is lower, and the production process is safer and more efficient. In addition, the electrolysis reaction condition is mild, the by-product waste is less, the environmental pollution is small, and the phosphorus pentafluoride gas with a purity greater than 99.99% can be obtained.

Lithium-ion battery, characterized in that it comprises: an electrolyte comprising a lithium salt and a first additive, wherein the lithium salt comprises lithium hexafluorophosphate, wherein a mass fraction of the lithium hexafluorophosphate, based on a total mass of the electrolyte, is 15% to 20%; wherein the first additive comprises at least one of lithium difluoro(oxalato)borate LiDFOB and lithium tetrafluoroborate LiBF4, and wherein a mass fraction of the first additive, based on the total mass of the electrolyte, is 30 ppm to 1200 ppm;a positive electrode plate comprising a positive electrode current collector and a positive electrode film layer arranged on at least one side of the positive electrode current collector and containing a positive electrode active material, wherein the positive electrode active material comprises a compound with a molecular formula LidNiaCobMncM(1-abc)Q, where 0 < d ≤ 2.1, 0.6 < a < 1, 0 < b < 1, 0 < c < 1, 0.6 < a + b + c < 1 and 1.8 ≤ z ≤ 3.5; wherein the element M comprises at least one of the elements B, Mg, Al, Si, P, S, Ca, Sc, Ti, V, Cr, Fe, Cu, Zn, Sr, Y, Zr, Nb, Mo, Cd, Sn, Sb, Te, Ba, Ta, W, Yb, La and Ce; and wherein the element Q comprises at least one of the elements O and F, wherein a mass fraction of the element Ti, based on a total mass of the positive electrode active material, is 100 ppm to 600 ppm; or a mass fraction of the element Zr, based on the total mass of the positive electrode active material, is 500 ppm to 2550 ppm.

The application discloses an ultralow-temperature aluminum electrolytic capacitor and a preparation method thereof. The capacitor comprises an anode foil, a cathode foil, an electrolytic paper between the anode foil and the cathode foil, and an electrolyte solution contained in the electrolytic paper. The electrolyte solution comprises, by weight percentage, propylene carbonate 15-25%, methyl ethyl carbonate 20-28%, diethylene glycol dimethyl ether 16-26%, lithium tetrafluoroborate 7-12%, lithium bisfluorosulfonylimide 2-5%, lithium difluorobisoxalate borate 2-5%, vinyl sulfate 4-8%, methanedisulfonate methylene 1.5-3.5%, mesoporous silicon dioxide 4-9%, lithium hexafluorophosphate 0.2-1.0%, lithium bis-trifluoromethanesulfonylimide 1.5-5%, a chelating agent 0.01-0.05%, and p-nitrophenol 0.3-1.2%. The preparation method comprises core wrapping, drying treatment, ring-type immersion, liquid removal treatment, assembly waist bundling, and aging treatment. The capacity retention rate of the capacitor can reach more than 90% at an ultralow temperature of -55 DEG C, and the Z ratio is only 1.29, so that the ultralow temperature and high temperature stability are synergistically improved.

The application discloses a water cooling equipment for lithium hexafluorophosphate manufacturing and a use method thereof, and belongs to the technical field of water cooling equipment. The water cooling equipment comprises a reaction kettle and a heat preservation barrel. Cooling pipes for introducing external cooling medium are coiled in the space between the heat preservation barrel and the outer wall of the reaction kettle, and form an external cooling loop. A sealing cover is internally provided with a gas filling mechanism for conveying and dispersing reaction gas into the reaction kettle. The application is provided with the gas filling mechanism, a driving assembly and a cold storage pipe. The external cooling pipe is used to preliminarily cool the kettle wall. In combination with the process that the low-temperature medium passes through the branch pipe to immediately internally cool the high-temperature gas, and the process that the first servo motor drives the receiving pipe and the porous exhaust assembly to rotate at high speed to generate strong shearing force, the "internal and external double cooling" mechanism is constructed, the local hot spots of the gas-liquid interface are completely eliminated, the large bubbles are broken into micro-bubbles to greatly increase the gas-liquid contact area, and thus the problem of low reaction efficiency is effectively solved.

To address the issues of poor cycle performance and heat resistance in lithium-ion batteries, this invention provides a non-aqueous electrolyte and a lithium-ion battery. The non-aqueous electrolyte, by weight (100%), comprises the following components: 5%–20% lithium hexafluorophosphate, 1%–10% lithium difluorosulfonylimide, 0.1%–2% hexamethylene diisocyanate, 0.1%–2.5% 3-fluoro-1,3-propanesulfonyl lactone, and the balance being an organic solvent composed of symmetrical chain carbonates, cyclic carbonates, and chain carboxylic acid esters. The non-aqueous electrolyte provided by this invention effectively improves the wettability between the non-aqueous electrolyte and the electrode sheet, facilitating lithium-ion diffusion. Simultaneously, it exhibits good chemical stability at high temperatures, thereby significantly improving the cycle life and high-temperature resistance of lithium-ion batteries.

The application provides an electrolyte, a preparation method thereof, a lithium battery and application. According to mass percentage, the electrolyte comprises 16.5-21% of lithium hexafluorophosphate, 0.5-2% of lithium difluoro(oxalato)borate, 0.1-2% of sodium hexafluorophosphate and 0.6-1% of a pyrrole ionic liquid, and the rest is a solvent. The compatibility of the electrolyte with lithium metal is improved. When the electrolyte is applied to the lithium battery, the phenomena of gas generation expansion and uneven deposition can be improved, and the cycle performance and safety performance of the lithium battery are improved.

This application relates to the field of material recycling technology after lithium-ion battery dismantling, and in particular to a pretreatment method for waste electrolyte after lithium-ion battery dismantling and a method for the complete recovery of lithium, fluorine, and phosphorus from it. The pretreatment method includes step S1: mixing the recovered electrolyte with a first reducing iron source, a first inorganic acid, and pure water, and reacting the mixture. After the reaction, solid-liquid separation is performed to obtain a first liquid, wherein the electrolyte in the first liquid includes lithium hexafluorophosphate. Step S2: adjusting the pH of the first liquid to 1.5–2.0, and removing H2PO2 from the first liquid... ‑ Oxidized to PO4 3‑ The electrolyte precipitates as a solid, and after the reaction, solid-liquid separation is performed to obtain a second liquid and a solid precipitate. This pretreatment method can effectively separate lithium and fluorine from phosphorus in waste electrolyte, thereby improving the product yield and purity of subsequent recovery steps, and the entire process causes almost no environmental pollution.

The application relates to a lithium hexafluorophosphate preparation drying device, which comprises a tank body, a ring cylinder part and a double-cone part, a heat exchange jacket is arranged on the periphery of the tank body, a rotating installation assembly is arranged on the tank body, the rotating installation assembly comprises a support, heat exchange output pipes and dehumidification pipes which are rotatably arranged on the two sides of the support, the heat exchange output pipes are sleeved with hot gas inlet pipes, a rotating assembly is arranged on the tank body and is used for driving the tank body to rotate, corresponding hammering plates are movably arranged on the two sides of the double-cone part along the rotating direction of the tank body, the hammering plates are connected to the outer sides of the double-cone part through connecting springs and are fixedly connected with rubber hammer heads inwards, with the rotation of the tank body, when the hammering plates rotate to the bottom side, the hammering plates move outwards, when the hammering plates rotate upwards, the hammering plates move inwards to drive the rubber hammer heads to flexibly hammer the tank body. The application can effectively increase the kinetic energy of the material in the process of material turning, reduce the adhesion of the material on the inner wall of the tank body, and effectively improve the drying efficiency.

The utility model discloses a high -purity lithium hexafluorophosphate production device, include: drying bottom case, drying bottom case top is equipped with separation middle case, separation middle case top is equipped with feeding inverted trug through box, and the both sides symmetry of separation middle case are equipped with sliding inclined mouth, and the inboard lower extreme of separation middle case is fixedly connected with the partition board spare, and separation middle case inside and outside are equipped with separation mechanism together, and the back lower extreme of drying bottom case is fixedly connected with the drying fan, and the back middle part screw thread connection of drying bottom case has the wall pipe, and the inside fixed connection of wall pipe has the filter screen, and the inside fixed connection of drying bottom case has the isolation board, the utility model discloses through motor no.

This invention discloses a continuous synthesis method and apparatus for liquid lithium hexafluorophosphate, comprising the following steps: S1, continuously adding lithium fluoride and an organic solvent into a mixing vessel to obtain lithium fluoride mother liquor, and continuously introducing a phosphorus pentafluoride mixed gas into a primary reactor; S2, continuously conveying the lithium fluoride mother liquor to the primary reactor for reaction with the phosphorus pentafluoride mixed gas; the primary reactor conveys the reacted material to a secondary reactor, while simultaneously conveying the unreacted phosphorus pentafluoride mixed gas to the secondary reactor for further reaction; S3, the secondary reactor transfers the unreacted gas out of the reaction system; the material obtained from the secondary reactor is continuously collected into a settling tank; S4, the top of the settling tank collects the synthesis liquid without lithium fluoride solids into a product receiving tank. This invention solves the synthesis efficiency bottleneck of traditional batch reactors and effectively improves the production capacity of liquid lithium hexafluorophosphate per unit time.

This application relates to the field of lithium hexafluorophosphate production technology, specifically disclosing a high-efficiency reactor for lithium hexafluorophosphate production. The reactor includes a reactor body and a stirring shaft positioned at the center of the reactor body. A motor is fixedly connected to the top of the stirring shaft. A circular opening is formed at the center of the top of the reactor body, and a flange seal connects to an air inlet cylinder extending into the reactor body. A channel is formed at the center of the top of the air inlet cylinder, through which the stirring shaft extends into the bottom of the reactor body, forming an air inlet chamber between the stirring shaft and the air inlet cylinder. An air inlet pipe is provided at the top of the reactor body, extending into the reactor body, with its end penetrating the air inlet cylinder and communicating with the air inlet chamber. Gas is transported from top to bottom along the air inlet chamber into the reactor to participate in the reaction, resulting in a long residence time of the reactant gas in the reactor, thus ensuring that most of the gas participates in the reaction and improving reaction efficiency.

The application belongs to the technical field of lithium battery electrolyte, and particularly relates to a lithium hexafluorophosphate solution purification method. Under the precondition of nitrogen pre-purification, perfluoro-cycloalkane is used to deeply remove water, and then trimethylsilane is used to deeply remove acid, so that the water content and the acidity of the lithium hexafluorophosphate solution are reduced to below 2 ppm, and no impurities are left, which can not only significantly improve the instant quality of the lithium hexafluorophosphate solution, but also improve the storage stability of the lithium hexafluorophosphate solution. The innovative method breaks the conventional cognition that perfluoroalkane is not suitable for water removal operation due to hydrophobicity, and unexpected technical effects are achieved.

The non-aqueous electrolyte solution involved in this embodiment includes lithium hexafluorophosphate, lithium bis(fluorosulfonyl)imide, and lithium nitrate. In the non-aqueous electrolyte involved in this embodiment, the molar ratio of lithium nitrate to lithium hexafluorophosphate is 0.01 or more and 0.15 or less, and the molar ratio of lithium bis(fluorosulfonyl)imide to lithium hexafluorophosphate is 0.1 or more and 1.0 or less.

This application relates to the field of lithium-ion battery technology and discloses a lithium iron phosphate battery with improved low-temperature performance and its preparation method. The battery includes a positive electrode, a pre-lithiated negative electrode, a separator, and a low-temperature electrolyte. The positive electrode comprises lithium iron phosphate coated with nano-carbon; the negative electrode comprises modified artificial graphite doped with soft carbon and treated with a dual-load pre-lithiation reagent containing lithium 1-methylnaphthalene and lithium biphenyl; the low-temperature electrolyte comprises a base solvent such as 2-methyltetrahydrofuran and ethyl propionate, a main lithium salt composed of lithium hexafluorophosphate and lithium difluorosulfonylimide, and film-forming additives such as lithium difluorooxalate borate, vinyl sulfate, and tris(trimethylsilane) phosphate. This invention reduces the low-temperature impedance of the battery and improves the discharge capacity under low-temperature conditions through the synergistic effect of modified positive and negative electrode materials, dual-load pre-lithiation supplementing active lithium, and a specific low-temperature electrolyte, while also considering the battery's room-temperature cycle stability and high-temperature storage performance.

The present application relates to the technical field of battery, in particular to an electrolyte and a lithium ion battery. The electrolyte comprises a lithium salt and an organic matter; the organic matter comprises a carbonate, a sulfur-containing substance and a carboxylic acid ester; the lithium salt comprises lithium bis(trifluoromethanesulfonyl)imide and lithium hexafluorophosphate; the total mass content of the sulfur-containing substance and the carboxylic acid ester in the organic matter is 70%-95%; the mass content C1 of the carbonate in the organic matter is 5%-30%; the mass content C2 of the sulfur-containing substance in the organic matter is 15%-30%; the mass content C3 of the carboxylic acid ester in the organic matter is 40%-65%; C1 / C2 is 0.2-3.5; and the sulfur-containing substance comprises a fluorosulfonyl amide compound. The electrolyte of the present application has high-temperature and high-pressure stability, and realizes significant improvement in battery furnace temperature safety and high-temperature cycle performance under a high-voltage and high-silicon system.

Improved electrolytes for lithium-based cells can include a dual salt combination of lithium hexafluorophosphate and lithium bis(fluorosulfonyl)imide or lithium bis(trifluoro-methanesulfonyl)imide, and a solvent that includes dimethyl carbonate, ethylmethyl carbonate and 5 to 25 volume percent of fluoroethylene carbonate. The improved electrolytes can include additives triethyl phosphate, ethoxy(pentafluoro)cyclotriphosphazene, 1,3-propane sultone, or mixtures thereof, and have small limited amounts of additional cosolvents and / or lithium-free organic additives. The improved electrolytes can be used to prepare lithium-based cells with silicon-based active materials as negative electrodes and nickel rich lithium metal oxides as positive electrodes. The lithium-based cells can achieve high energy, high power, fast charge and long cycle life along with good thermal stability.

The present disclosure provides an electrolyte comprising: an electrolyte comprising: (a) a primary lithium salt; (b) a secondary lithium salt; and (c) an additive; wherein the primary lithium salt is lithium hexafluorophosphate (LiPFe); the primary lithium salt and the secondary lithium salt are in a mole ratio range of 4:1 to 6:1; and the additive is selected from vinylene carbonate, propane sultone, lithium difluoro(oxalato)borate (LiDFOB), 1,3,6 hexanetricarbonitrile (HTCN), or combinations thereof. The present disclosure further provides an electrochemical cell comprising the electrolyte as disclosed herein.

The application discloses a kind of flame-retardant lithium ion battery electrolyte and preparation method thereof, belong to lithium ion battery electrolyte technical field, raw material includes diethyl carbonate, methyl ethyl carbonate, ethylene carbonate, lithium hexafluorophosphate, lithium difluoro (oxalato) borate and flame-retardant additive, wherein, diethyl carbonate, methyl ethyl carbonate, ethylene carbonate are solvent together, lithium hexafluorophosphate is lithium salt, lithium difluoro (oxalato) borate is lithium salt additive;Flame-retardant additive is with methyl methacrylate as shell material, with phosphoric acid ester flame retardant doped with heptafluorocyclopentane nano-capsule as core material, is prepared by suspension polymerization, can be uniformly dispersed in electrode liquid matrix, realizes that flame retardant and electrode surface are physically isolated, avoid phosphoric acid ester compound and negative electrode material sustained direct contact and interface side reaction, help to reduce the influence on lithium ion battery cycle performance.