747 results about "Lithium hexafluorophosphate" patented technology

The invention provides a lithium ion battery and electric equipment, the lithium ion battery comprises a positive pole piece and an electrolyte, active substances in the positive pole piece comprise a phosphate lithium positive pole material and nickel cobalt manganese lithium oxide, and the electrolyte comprises a positive pole film-forming agent, a negative pole film-forming agent and a lithium salt, the lithium salt comprises lithium hexafluorophosphate and lithium bis (fluorosulfonyl) imide, the lithium ion battery meets the following formula: # imgabs0 #, NL is the mass ratio of the lithium nickel cobalt manganese oxide to the lithium phosphate positive electrode material, Salt is the sum of the molar concentrations of the lithium hexafluorophosphate and the lithium bis (fluorosulfonyl) imide in the electrolyte by taking mol / L as the unit, and the sum of the molar concentrations of the lithium hexafluorophosphate and the lithium bis (fluorosulfonyl) imide in the electrolyte is the sum of the molar concentrations of the lithium hexafluorophosphate and the lithium bis (fluorosulfonyl) imide. Add is the mass ratio of the positive electrode film-forming agent to the negative electrode film-forming agent. When the ternary material is doped in the lithium manganese iron phosphate or the lithium iron phosphate, the proportion of the positive and negative electrode film-forming agents and the proportion of the heat-resistant high-lithium salt can be adjusted according to the mixing proportion of the lithium manganese iron phosphate and the lithium iron phosphate, so that the cycle performance of the battery is improved.

The invention discloses an electrolyte with a temperature switch function and a preparation method and application thereof, and relates to the technical field of lithium ion batteries. The electrolyte provided by the invention comprises the following components: lithium salt, a first organic solvent and a polymer, the lithium salt is at least one of lithium bis (trifluoromethylsulfonyl) imide, lithium bis (fluorosulfonyl) imide, lithium hexafluorophosphate, lithium tetrafluoroborate, lithium difluoro (oxalato) borate and lithium bis (oxalato) borate; the polymer is polymethacrylate, and the first organic solvent is [Cnmim] [TFSI]. According to the electrolyte, the reversible phase transformation process is realized, the electrode reaction can be closed at high temperature, and the lithium battery is prevented from being out of control due to overheating; and when the temperature is reduced to normal temperature, the battery can work normally. The phase transition temperature of the electrolyte is flexible and controllable, and the phase transition temperature can be regulated and controlled to a reasonable interval by optimizing the composition of the electrolyte and the dosage (concentration) of each component, that is, the phase transition temperature is higher than the normal working temperature of the battery and lower than the initial temperature of the heat release side reaction.

The present application provides a method for recovering waste electrolyte of lithium-ion batteries, wherein the waste electrolyte contains lithium hexafluorophosphate, comprising the following steps: S1: adding a saline solution as an extractant to the collected waste electrolyte for extraction, separating a lower organic solution and an upper aqueous solution, and recovering the lower organic solution to obtain an organic solvent; S2: adding a water-soluble carbonate and / or a water-soluble phosphate to the upper aqueous solution in step S1, filtering, and separating to obtain a lithium precipitate. The recovery method can achieve efficient separation and recovery of organic solvents and lithium elements in waste electrolytes, is simple and easy to operate, is economical and environmentally friendly, has strong applicability, and can be prepared and produced on a large scale.

A non-aqueous electrolyte for a lithium-ion cell includes a base electrolyte consisting of lithium hexafluorophosphate or lithium bis(fluorosulfonyl)imide or a combination thereof in methyl propionate; about 2 to about 15 parts by weight, preferably about 6 to about 15 parts by weight of vinylene carbonate; and about 0.5 to about 5 parts by weight, preferably about 2 to about 5 parts by weight of an additive comprising lithium difluorophosphate, lithium difluoro(oxalate)borate, lithium bis(oxalate)borate, or a combination thereof, wherein the content of the vinylene carbonate and the additive are each based on a total weight of the base electrolyte, the vinylene carbonate, and the additives.

The invention relates to the technical field of lithium batteries, and provides a lithium ion secondary battery. The battery comprises a positive plate, a negative plate and electrolyte, the positive plate comprises lithium iron phosphate particles, and the Dv50 of the lithium iron phosphate particles is 5-15 [mu] m; the electrolyte comprises an organic solvent, and the organic solvent comprises a linear organic solvent and an annular organic solvent; the linear organic solvent comprises linear carbonic ester and linear carboxylic ester, and the cyclic organic solvent comprises cyclic carbonic ester; based on the total mass of the electrolyte, the mass ratio of the cyclic carbonate is recorded as S1, the mass ratio of the linear carbonate is recorded as S2, and the mass ratio of the linear carboxylic ester is recorded as S3; s = (S2 + S3) / S1; s satisfies 1.5 < = S < = 20; the electrolyte comprises lithium bis (fluorosulfonyl) imide and lithium hexafluorophosphate; the mass ratio of the lithium bis (fluorosulfonyl) imide to the lithium hexafluorophosphate is recorded as L, Lgt; 1. The battery provided by the invention has relatively good low-temperature discharge performance and high-temperature cycle performance.

The invention discloses a battery monomer, a battery device and electric equipment, the battery monomer comprises a positive pole piece, the positive pole piece comprises a positive pole film layer, and the positive pole film layer comprises a lithium iron phosphate material and a lithium supplement agent; the negative electrode plate comprises a negative electrode film layer, the negative electrode film layer comprises a negative electrode active material, and the negative electrode active material comprises graphite; the isolating membrane is positioned between the positive pole piece and the negative pole piece; the electrolyte comprises lithium salts, the lithium salts comprise an organic lithium salt and an inorganic lithium salt, the organic lithium salt comprises at least one of fluorine-containing lithium sulfimide, fluorine-containing lithium oxalato borate and fluorine-containing lithium oxalato phosphate, the inorganic lithium salt comprises at least one of lithium hexafluorophosphate, lithium tetrafluoroborate and lithium fluorosulfonate, and the organic lithium salt comprises at least one of fluorine-containing lithium sulfimide, fluorine-containing lithium oxalato borate and fluorine-containing lithium oxalato phosphate. The mass ratio of the inorganic lithium salt to the organic lithium salt is (6-2): 1. As a result, a battery cell having both a long life and high power is obtained.

The embodiment of the invention provides an electrolyte, a battery and a power utilization device, the electrolyte comprises a lithium salt, a first additive and a second additive, the lithium salt comprises lithium hexafluorophosphate, the second additive is lithium fluorosulfonate, and the first additive has a structure as shown in a formula (1). The first additive and the second additive have a synergistic effect, an organic-inorganic composite CEI film is formed on the positive electrode, meanwhile, an inorganic SEI film with high ionic conductivity is formed on the negative electrode, and the CEI film and the SEI film can reduce side reactions between the electrode and an electrolyte, so that damage to the surface structure of the electrode and decomposition gas production of the electrolyte are reduced, and the service life of the electrolyte is prolonged. The cycle performance of the battery is improved; and the inorganic SEI film with high ionic conductivity can improve the transmission rate of conductive ions, so that the power performance of the battery is improved, and the battery has relatively good cycle performance and power performance.

The invention relates to a preparation method of a gel electrolyte with an efficient flame-retardant characteristic. The gel electrolyte is mainly composed of a gel matrix, a flame retardant and an electrolyte solution. The invention provides a method for preparing a flame-retardant gel electrolyte, and application of the flame-retardant gel electrolyte in energy storage equipment such as a lithium ion battery is described in detail. The flame-retardant gel electrolyte has excellent flame retardance, and the safety performance of a battery system can be effectively improved. The preparation method comprises the following specific synthesis steps: (1) firstly, mixing polyethylene oxide (PEO) with a solvent, then adding lithium hexafluorophosphate (LiPF6) electrolyte salt, and uniformly stirring to form a uniform solution; and (2) adding trifluoroethyl methacrylate and a PEGDMA initiator into the solution, carrying out polymerization reaction to form a composite skeleton, and infiltrating the electrolyte under the swelling action to finally form the gel electrolyte. And (3) drying the swelled gel electrolyte to remove redundant solvent and moisture, and then cutting and packaging to obtain the gel electrolyte with high flame retardance. The flame retardance of the electrolyte is remarkably improved by reducing the using amount of the electrolyte and polymerizing and curing the electrolyte.

The invention relates to the technical field of lithium ion batteries, in particular to a non-aqueous electrolyte and a lithium ion battery. The non-aqueous electrolyte comprises an organic solvent, a lithium salt, difluorophosphate ions, tris (trimethylsilyl) phosphate and a first additive; the lithium salt comprises lithium hexafluorophosphate; the non-aqueous electrolyte satisfies the following conditions: 0.05 < = a / b < = 20, 0.03 < = a / c < = 15, 0.05 < = c * d / b < = 20, 0.01 < = a < = 1, 0.01 < = b < = 1.2, 0.01 < = c < = 0.8, and 1.1 < = d < = 1.3. According to the non-aqueous electrolyte disclosed by the invention, the advantages of tris (trimethylsilyl) phosphate that the impedance of a battery is reduced and a high-stability LiF-rich interfacial film is formed can be fully exerted, meanwhile, the defect that tris (trimethylsilyl) phosphate catalyzes decomposition of lithium salt to generate unfavorable byproducts is greatly inhibited, and relatively low initial impedance and excellent high-temperature quick-charge cycle performance can be considered on the battery level; and the problem of rapid increase of impedance under high-temperature rapid charging circulation is inhibited.

The invention relates to a battery monomer, a battery device and a power utilization device, the battery monomer comprises an electrode assembly and an electrolyte, the electrode assembly comprises a positive pole piece, the positive pole piece comprises a positive active material layer, and the positive active material layer comprises lithium-containing phosphate of an olivine structure; the electrolyte comprises, by mass, 8-30% of a carboxylic ester solvent, a lithium salt and an unsaturated ester additive, the lithium salt comprises lithium hexafluorophosphate and fluorine-containing lithium sulfimide, the mass content of the fluorine-containing lithium sulfimide in the lithium salt is 18-45%, the mass content of the unsaturated ester additive in the electrolyte is 0.05-5%, and the mass content of the unsaturated ester additive in the electrolyte is 0.05-5%. The unsaturated ester additive comprises one or more of vinylene carbonate, vinylethylene carbonate, allyl ethyl carbonate and a fluoro-carbonate additive; the amount of electrolyte in the battery cell is 2.8 g / Ah to 3.2 g / Ah. According to the invention, rapid charging and use reliability of the single battery can be considered.

The invention discloses a lithium hexafluorophosphate crystallization and separation device, and relates to the technical field of lithium hexafluorophosphate crystallization and separation, the lithium hexafluorophosphate crystallization and separation device comprises a fixed seat and support legs symmetrically fixed on the periphery of the bottom of the fixed seat, the interior of the fixed seat is fixedly connected with an outer box body, and the lithium hexafluorophosphate crystallization and separation device further comprises an air inlet, an air outlet and an air outlet, an air outlet is formed in the other side of the top of the outer box body; the liquid outlet is formed in the middle of the bottom of the outer box body; the outer barrel body is installed in the outer box body, an inner barrel body is connected to the interior of the outer barrel body in a clamped mode, and a cleaning brush is installed on the lower portion of the partition plate; the swing mechanism is arranged on one side of the outer barrel; and the cleaning mechanism is arranged below the partition plate, and the problems that a lithium hexafluorophosphate solution in the device is in direct contact with the barrel for a long time, so that the barrel is easily corroded and damaged, and large lithium hexafluorophosphate crystals are still possibly contained in the device during discharging, so that the subsequent smooth discharging of the lithium hexafluorophosphate crystals is inconvenient are solved.

The invention relates to the technical field of lithium batteries, and provides a lithium ion secondary battery. The battery comprises a positive plate, a diaphragm and a negative plate which are laminated, the positive plate comprises lithium iron phosphate; the diaphragm is formed by a base film; the battery also comprises an electrolyte; the electrolyte comprises lithium bis (fluorosulfonyl) imide and lithium hexafluorophosphate; based on the total mass of the electrolyte, the mass ratio of the lithium bis (fluorosulfonyl) imide is recorded as L2, and the mass ratio of the lithium hexafluorophosphate is recorded as L1; l2 and L1 satisfy the following conditions: 0.1 < = L2 / L1 < = 4.6; the electrolyte comprises a linear organic solvent and an annular organic solvent; the linear organic solvent comprises linear carbonic ester and linear carboxylic ester, and the cyclic organic solvent comprises cyclic carbonic ester; the mass ratio of the linear organic solvent to the annular organic solvent is marked as W, and W is greater than or equal to 1; when the conditions are met, the high and low temperature performance and the safety performance of the battery can be effectively improved.

The invention relates to a preparation technology of a gel polymer lithium ion battery cell electrolyte, and belongs to the field of battery preparation technologies, the preparation technology comprises the following steps: mixing methacrylate monomers and silane monomers according to a mass ratio of 3: 1-5: 1, adding 1-3% of an initiator, and carrying out prepolymerization at 60-80 DEG C for 1-3 h to prepare a prepolymer solution; mixing with a non-aqueous solvent containing lithium hexafluorophosphate according to a mass ratio of (1: 4)-(1: 6) to form a precursor mixed solution, and controlling the injection rate to be 1.5-2.5 g / Ah to a gap between a battery cell pole piece and a diaphragm; after standing for 2-4 hours at the vacuum degree of less than or equal to-0.08 MPa, curing for 3-6 hours at the temperature of 60-70 DEG C to form a gel polymer electrolyte; the wettability is improved through pole piece surface hydrophilic treatment, 1-5% of vinylene carbonate is added to optimize an SEI film, the prepolymerization temperature fluctuation is controlled to be smaller than or equal to + / -2 DEG C through microwave-assisted heating, the pressure of 0.2-0.5 MPa is applied after injection to promote uniform permeation, a polyvinylidene fluoride coating of 5-10 microns is coated after curing to enhance protection, and the interface performance is ensured through an alternating-current impedance test.

The invention provides a battery monomer, a battery device and electric equipment, the battery monomer comprises an electrode assembly and an electrolyte, the electrode assembly comprises a positive pole piece and a negative pole piece, the positive pole piece comprises a positive current collector and a positive active material layer arranged on at least one side of the positive current collector, and the positive active material layer comprises a positive active material; the positive electrode active material comprises lithium-containing phosphate, and the compaction density of the positive electrode plate is 2.46 g / cm < 3 >-2.8 g / cm < 3 >; the negative pole piece comprises a negative current collector and a negative active material layer arranged on at least one side of the negative current collector, and the compaction density of the negative pole piece is 1.25 g / cm < 3 >-1.5 g / cm < 3 >; the electrolyte comprises fluorine-containing lithium sulfimide and lithium hexafluorophosphate, and based on the total mass of the electrolyte, the ratio of the mass ratio of the fluorine-containing lithium sulfimide to the mass ratio of the lithium hexafluorophosphate is 0.4-0.8; and the mass of the electrolyte corresponding to each Ah of the battery monomer is 2.2-3g.

The invention discloses an electrolyte for a lithium manganate lithium ion battery and a preparation method thereof, and the electrolyte comprises the following components in percentage by mass: 70-90% of an organic solvent, 5-20% of a lithium salt and 0.5-10% of an additive, the organic solvent is formed by mixing cyclic carbonate and chain carbonate according to the mass ratio of (10-30): (70-90); the lithium salt adopts one or more of lithium hexafluorophosphate (LiPF), lithium tetrafluoroborate (LiBF) and lithium bis (trifluoromethane sulfonimide) (LiTFSI), and the concentration of the lithium salt is 0.8 to 1.5 mol / L; the additives comprise a manganese ion complexing agent, a film forming accelerant and an antioxidant. In the invention, the manganese ion inhibition effect is as follows: the complexing agent and Mn (II) ions form a stable complex, so that the concentration of free Mn (II) in the electrolyte is reduced by more than 80%, migration and deposition of the free Mn (II) to the negative electrode are inhibited, and the dissolution amount of the Mn element of the positive electrode is reduced by 65% after 500 times of circulation at 45 DEG C.

The invention relates to the technical field of lithium batteries, in particular to a low-temperature electrolyte and a lithium battery containing the low-temperature electrolyte, the low-temperature electrolyte comprises the following components in percentage by mass: 75-85% of solvent, 11-18% of electrolyte salt and 0.5-2% of additive, the electrolyte salt comprises one or more of lithium hexafluorophosphate, lithium difluoro (oxalato) borate, lithium bis (fluorosulfonyl) imide and lithium bis (trifluoromethanesulfonyl) imide, and the additive comprises a film-forming agent, a low-temperature reinforcing agent and a dendritic crystal inhibitor. By optimizing the synergistic effect of the solvent system and the electrolyte salt, the freezing point and viscosity of the electrolyte are effectively reduced, the migration rate of lithium ions at low temperature is enhanced, and it is ensured that the battery can still be efficiently charged and discharged under the low-temperature condition.

The invention relates to a high-performance lithium-rich manganese-based lithium ion battery electrolyte with a flame-retardant function and a preparation method thereof, the high-performance lithium-rich manganese-based lithium ion battery electrolyte comprises a lithium salt and an electrolyte organic solvent, the lithium salt is a composite lithium salt, the composite lithium salt comprises lithium hexafluorophosphate and lithium salt additive lithium difluoro (oxalato) borate, and the electrolyte solvent comprises the electrolyte organic solvent and an additive, the additive comprises a positive electrode film-forming additive tris (trimethylsilane) phosphate and a flame-retardant additive ethyoxyl (pentafluoro) cyclotriphosphazene. The electrolyte has the advantages that the electrolyte not only has excellent cycle performance, but also has a flame-retardant function.

The invention discloses a lithium ion battery electrolyte, a preparation method and application. The lithium ion battery electrolyte comprises a lithium salt and an organic solvent, wherein the lithium salt comprises a combination of at least two of lithium hexafluorophosphate, lithium difluoro bis (oxalato) phosphate, lithium bis (fluorosulfonyl) imide and lithium bis (oxalato) borate, and the organic solvent comprises 30 wt%-50 wt% of hydrofluoroether, 10 wt%-30 wt% of acetate and 20 wt%-60 wt% of carbonate. The lithium ion battery electrolyte provided by the invention can keep the diaphragm structure complete, realizes filling of pores with lithium salt, and reduces the permeability of the diaphragm, thereby controlling possible shrinkage of the diaphragm in a temperature change process under a low-temperature or high-temperature condition; the crosstalk problem caused by gas penetration between the positive electrode and the negative electrode is inhibited, and the battery prepared by utilizing the lithium ion battery electrolyte provided by the invention has good cycle performance and rate capability under a low-temperature condition and has relatively high safety under a high-temperature condition.

The invention discloses a lithium hexafluorophosphate production control system and a method thereof, and relates to the technical field of lithium hexafluorophosphate production, and the method specifically comprises the following steps: obtaining crystallization dynamic information of each area in a reaction kettle in a lithium hexafluorophosphate crystallization process in real time, and analyzing after obtaining to obtain a crystallization dynamic result; respectively generating a crystal growth driving force coefficient and a particle uniform distribution index of each region; constructing a particle size distribution evaluation model for the generated crystal growth driving force coefficient and particle uniform distribution index of each region, generating a particle size distribution coefficient of each region, and performing comprehensive analysis after generation to generate an evaluation coefficient; and analyzing the generated evaluation coefficient, and evaluating the uniformity degree of particle size distribution in the reaction kettle in the lithium hexafluorophosphate crystallization process. The problem of uneven particle size distribution in the lithium hexafluorophosphate crystallization process is solved, and the effect of improving the particle size uniformity and the product quality stability is achieved.

A non-woven battery separator and processes for forming the non-woven battery separator includes a fiber blend including cellulose fibers, microfibrillated fibers, and optionally polyester and / or aramid fibers. Also disclosed are batteries including the non-woven battery separator. During fabrication, the non-woven battery separator can be effectively dried at temperatures between 120°C and 180°C, which results in the fibers absorbing water when in use. Some battery electrolytes such as lithium hexafluorophosphate react with water to form hydrogen fluoride (HF), which can be corrosive and shorten battery lifecycles and affect performance. Absorbing water from the electrolyte increases the battery life cycle by reducing HF generation.

The invention provides a positive electrode material and a preparation method thereof, a positive electrode slurry, a positive electrode plate, a lithium ion battery and a preparation method thereof, the positive electrode material is applied to a battery, the battery comprises an electrolyte, the electrolyte comprises lithium hexafluorophosphate and an organic solvent, the positive electrode material comprises a positive electrode active substance and lithium carbonate, and the organic solvent comprises lithium hexafluorophosphate and lithium carbonate. The lithium carbonate is coated on the surface of the positive active material, and the mass ratio of the positive active material to the lithium carbonate is 1: (0.001-0.03). The surface of the positive active material is coated with a layer of lithium carbonate, the lithium carbonate can react with lithium hexafluorophosphate in electrolyte, and a lithium difluorophosphate coating layer is generated on the surface of the positive active material in situ, so that the addition amount of lithium difluorophosphate in the battery can be effectively increased, and the performance of the battery is improved.

The invention discloses a highly efficient synthesis device for synthesizing lithium hexafluorophosphate, which comprises: a main cavity for containing low-temperature anhydrous hydrofluoric acid; a cover for sealing the main cavity to prevent leakage of gas entering the main cavity; a gas supply convex plate evenly embedded in the side wall of the main cavity, which is an integrated structure with the main cavity and is provided with a plurality of one-way gas delivery valves; a gas delivery device, comprising a gas delivery cavity and a plurality of gas delivery pipelines evenly connected to one side of the gas delivery cavity, the gas delivery cavity being connected to the gas supply convex plate and the one-way gas delivery valve thereon; and a stirring device, comprising a rotating shaft driven by a motor and an impeller arranged on the rotating shaft. The contact area between the gas and the solution is greatly increased, and at the same time, the contact position between the gas and the solution is made more uniform, which solves the problem that the gas in the existing ventilation method is easy to repeatedly contact with the local solution, while reducing the chance of contact with other parts of the solution, resulting in insufficient reaction and reduced synthesis efficiency of lithium hexafluorophosphate.

The invention belongs to the technical field of electrolyte, and particularly relates to a method for preparing liquid lithium hexafluorophosphate from sodium hexafluorophosphate. The method comprises the following steps: adding a sodium source into a hexafluorophosphoric acid aqueous solution for neutralization reaction to obtain a sodium hexafluorophosphate aqueous solution, then extracting to remove water, drying to obtain a sodium hexafluorophosphate solid, and heating and decomposing the sodium hexafluorophosphate solid to obtain phosphorus pentafluoride gas; the phosphorus pentafluoride gas is not mixed with SO3, POF3, HF and other impurity gases, a complex refining and purifying process is not needed, and the phosphorus pentafluoride gas with the purity exceeding 99.9% can be obtained after simple purification and can be directly used for synthesizing liquid lithium hexafluorophosphate. The method does not generate waste acid, does not need a complicated phosphorus pentafluoride gas purification process, is particularly suitable for the requirements of the lithium battery industry on high-purity electrolyte, and has the remarkable advantages of high product purity, small environmental pollution, low production cost and the like.

The application provides a lithium ion battery and an electric device, the lithium ion battery comprising a positive electrode sheet and an electrolyte, an active substance in the positive electrode sheet comprising a phosphate lithium positive electrode material and a lithium nickel cobalt manganese oxide, the electrolyte comprising a positive electrode film former, a negative electrode film former and a lithium salt, the lithium salt comprising lithium hexafluorophosphate and a lithium bisfluorosulfonylimide salt, the lithium ion battery satisfying the following formula: wherein NL is a mass ratio of the lithium nickel cobalt manganese oxide and the phosphate lithium positive electrode material, S alt is a value of a molar concentration of the lithium hexafluorophosphate and the lithium bisfluorosulfonylimide salt in the electrolyte in mol / L, and A dd is a mass ratio of the positive electrode film former and the negative electrode film former. The application can adjust the ratio of the positive electrode film former and the negative electrode film former and the ratio of the high-heat-resistance lithium salt according to the mixing ratio of the ternary material doped in the lithium manganese iron phosphate or the lithium iron phosphate, so that the cycle performance of the battery is improved.

The invention discloses an electrolyte, a lithium metal battery and an electronic device, and belongs to the technical field of battery materials. The electrolyte comprises lithium salts and an organic solvent, the lithium salts comprise a first lithium salt and a second lithium salt, and the organic solvent comprises fluorocarboxylic ester and fluoroamide; wherein the first lithium salt is selected from at least one of lithium hexafluorophosphate, lithium difluorophosphate, lithium difluoro (oxalato) phosphate, lithium tetrafluoro (oxalato) phosphate and lithium tetrafluoroborate, and the second lithium salt comprises lithium bis (trifluoromethylsulfonyl) imide and lithium difluoro (oxalato) borate in a mass ratio of 1: (1-10). According to the electrolyte, the lithium metal battery can be charged / discharged at-40 DEG C and 0.1 C, the constant-current charging ratio exceeds 80%, and the application field and range of the lithium metal battery are widened.

A novel additive, an electrolyte, and a lithium ion battery, relating to the technical field of lithium ion batteries. The electrolyte comprises a lithium salt and a non-aqueous solvent for dissolving the lithium salt, the electrolyte further comprises an electrolyte additive, the electrolyte additive comprises a positive electrode film-forming additive and a negative electrode film-forming additive, and the electrolyte additive further comprises a fluoro isocyanate-based pyridazine organic compound. The additive can absorb moisture and hydrofluoric acid in the electrolyte, reduce the dissolution of transition metals, improve the thermal stability of lithium hexafluorophosphate, and maintains the stability of a ternary material under high voltage; a sulfuric acid group on the novel additive can be oxidized by oxygen at a positive electrode, so that the oxygen generated when an LFO lithium supplementing agent is activated is absorbed, the capacity exertion, high temperature cycle and high temperature storage of the LFO lithium supplementing agent are significantly improved, and the DCIR of the battery will not obviously increase, thereby improving the stability of the battery.

A continuous crystallizer for lithium hexafluorophosphate comprises a crystallizing tank, a spiral pipe is arranged in the crystallizing tank, a material inlet is formed in the top of the crystallizing tank, a material outlet is formed in the bottom of the crystallizing tank, and the two ends of the spiral pipe are in butt joint with the material inlet and the material outlet respectively; in conclusion, the crystallizing tank is provided with three temperature control areas, namely the pre-cooling cavity, the cooling cavity and the crystallizing cavity, and materials sequentially pass through the three temperature control areas of the crystallizing tank along the spiral pipe, so that gradient cooling crystallization is realized, crystallized particles grow uniformly, and the crystallization time is short.

The invention provides a lithium hexafluorophosphate preparation method, which comprises: 1, adding a molecular sieve into an acetonitrile solvent, uniformly shaking, and standing; step 2, filtering the mixture after standing to obtain a treated acetonitrile solvent, and regenerating and recycling the filtered molecular sieve; 3, preparing the dried potassium hexafluorophosphate and the treated acetonitrile solvent, and putting the mixture into a container; 4, stirring the solution in the container, adding lithium hydride in a stirring state, and introducing ammonia gas to carry out catalytic reaction until the reaction is finished; 5, filtering the reactant in the step 4, carrying out reduced pressure distillation on the filtrate, recovering part of the solvent, and carrying out cooling crystallization to obtain a complex of lithium hexafluorophosphate and acetonitrile; and step 6, filtering the complex in the step 5, and carrying out vacuum drying to obtain the lithium hexafluorophosphate. The method provides a green process for preparing the lithium hexafluorophosphate, which integrates safety, economy and environmental protection.

The present invention provides a synthesis system and a synthesis method for lithium hexafluorophosphate. The synthesis system comprises a gas-liquid reaction kettle and a built-in microbubble generation unit provided in the gas-liquid reaction kettle; a material inlet and a gas inlet are formed in the side wall of the gas-liquid reaction kettle; the built-in microbubble generation unit comprises a first microbubble generator and a second microbubble generator, the first microbubble generator is provided below the liquid level in the gas-liquid reaction kettle and connected to the material inlet, and the second microbubble generator is provided at the bottom end of the gas-liquid reaction kettle and connected to the gas inlet; a plurality of layers of perforated plates are successively provided in the gas-liquid reaction kettle from top to bottom; through holes of said perforated plates are staggered, and said perforated plates are provided between the first microbubble generator and the second microbubble generator. The synthesis system of the present invention increases the area of mass transfer between lithium fluoride liquid and phosphorus pentafluoride gas, increases the reaction rate, and reduces energy consumption.

The present invention belongs to the field of lithium ion batteries, and specifically relates to an in-situ preparation method and a recovery method for a solid polymer electrolyte, as well as a lithium ion battery. The preparation method provided by the present invention comprises the following steps: a) loading an electrolyte precursor onto a surface of a battery separator, and then assembling same with a lithium ion battery positive electrode and a lithium ion battery negative electrode, to obtain a semi-finished lithium ion battery product, components of the electrolyte precursor in step a) comprising a polymer monomer, a lithium salt and an initiator, the lithium salt being lithium perchlorate, lithium hexafluorophosphate, lithium difluorophosphate, or the like; b) under heating conditions, performing in-situ polymerization of the electrolyte precursor on the battery separator in the semi-finished lithium ion battery product, to obtain a solid polymer electrolyte loaded on the battery separator. The preparation method provided by the present invention does not require an additional catalyst, and the prepared solid polymer electrolyte can be depolymerized by means of heating, and has good environmental and economic benefits.