1611results about How to "Improve electrochemical performance" patented technology

The invention relates to the technical field of lithium iron phosphate production, and discloses a carbon-coated titanium-doped lithium iron phosphate positive electrode material and a preparation method thereof.The preparation method comprises the following steps that 1, a ferrous solution and a phosphorus source solution are mixed in proportion, dopamine hydrochloride is added, a pH regulator is dropwise added in the stirring state, the pH of the solution is adjusted to 4.0-5.5, a reaction is conducted, a titanium source solution is added, and a reaction solution is obtained; after uniformly stirring, continuously dropwise adding a pH regulator to regulate the pH value of the solution to 5.5-6.5; the iron phosphate octahydrate coated with the titanium-embedded polydopamine is obtained; 2) calcining the titanium-embedded polydopamine-coated ferrous phosphate octahydrate in an inert gas atmosphere to obtain carbon-coated titanium-doped anhydrous ferrous phosphate; 3) mixing the carbon-coated titanium-doped anhydrous ferrous phosphate with lithium phosphate and a carbon source, ball-milling, mixing, spray-drying and calcining to obtain a carbon-coated titanium-doped lithium iron phosphate positive electrode material; the synthesis process is simple, and energy consumption is reduced.

The invention discloses a pre-lithiated silicon-carbon negative electrode material as well as a preparation method and application thereof. The pre-lithiated silicon-carbon negative electrode material comprises composite particles and a surface coating layer coating the outer surfaces of the composite particles, the mass of the composite particles accounts for 85%-99% of the total mass of the pre-lithiated silicon-carbon negative electrode material; the composite particles are compounds of pre-lithiated porous carbon and nano silicon particles; the composite particles are obtained by uniformly depositing nano silicon particles in pores of pre-lithiated porous carbon; the mass of the pre-lithiated porous carbon accounts for 15-95% of the total mass of the composite particles; the pre-lithiated porous carbon comprises lithium metal particles and porous carbon, and the lithium metal particles are attached to the surfaces of pores of the porous carbon; the mass of the lithium metal particles accounts for 0.1-10% of the total mass of the pre-lithiated silicon-carbon negative electrode material; when the pre-lithiated silicon-carbon negative electrode material is applied to the lithium battery, the first-circle coulombic efficiency of the lithium battery can be improved.

The invention relates to the technical field of lithium ion batteries, and provides a lithium cobalt oxide composite material which comprises a core body and a coating layer coating the core body, the core body comprises O2-phase lithium cobalt oxide, and the O2-phase lithium cobalt oxide is doped with an element M; the coating layer comprises an oxide containing an N element; the M element comprises at least one of Al, Mg, W, Ti, La, Zr, Ni, Mn and Y; n comprises at least one of Al, Mg, Y, W, Nb, La, Zr, Ti and P. The lithium cobalt oxide composite material provided by the invention is used as a positive electrode material of a lithium ion battery, and the cycling stability of the lithium ion battery under high potential is improved.

The invention provides a low-cost preparation method of high-performance titanium-doped iron phosphate, and relates to the technical field of batteries. The low-cost preparation method comprises the following steps: S1, respectively preparing a phosphoric acid solution, a hydrogen peroxide solution, a phosphorus salt solution and a ferrite solution; s2, adding titanium sulfate into the ferrite solution to obtain an iron-titanium mixed solution; s3, directly adding ammonia water and a hydrogen peroxide solution into the phosphorus salt solution to obtain a phosphorus-oxygen mixed solution; s4, the iron-titanium mixed solution is heated, the phosphorus-oxygen mixed solution is put into the iron-titanium mixed solution, and slurry A is obtained; s5, obtaining a filter cake A; s6, adding pure water and a phosphoric acid solution, and heating to obtain slurry B; s7, obtaining anhydrous iron phosphate; the synthesized iron phosphate is compact and compact in morphology, internal pore channels of primary particles are still rich, the compaction density of the lithium iron phosphate material obtained through grinding and sintering reaches 2.613 g / cc, the 0.1 C discharge capacity can still reach 156.35 mAh / g, and the 1C discharge capacity reaches 131.47 mAh / g.

The invention belongs to the technical field of solar cell materials, and particularly relates to silver-coated copper powder and a preparation method thereof. A preparation method of silver-coated copper powder comprises the following steps that copper powder subjected to surface activation through an acid-base solution and a complexing agent are dissolved in water, and copper powder turbid liquid is obtained; dropwise adding a silver source solution into the copper powder turbid liquid to carry out a replacement reaction, and adjusting the pH value of the solution after the reaction to obtain a silver-coated copper powder precursor turbid liquid; and dropwise adding a reducing agent solution into the silver-coated copper powder precursor turbid liquid, then dropwise adding a silver source solution, carrying out oxidation-reduction reaction, carrying out solid-liquid separation, washing, and drying to obtain the silver-coated copper powder. According to the preparation method provided by the invention, in the chemical oxidation reduction process, the silver-coated copper powder with different silver layer distribution structures, compact silver coating structure and better performance is obtained by regulating and controlling the dropping sequence and dropping rate of the reducing agent solution and the silver source solution.

The invention discloses a porous substrate reinforced anion exchange membrane and a preparation method and application thereof, and relates to the technical field of anion exchange membranes. The porous substrate reinforced anion exchange membrane is prepared by the following steps: uniformly mixing a polyarylene alkylene type cationic polymer solution and a C1-C10 alcohol solvent, then coating two sides of a porous substrate with the mixture, and drying to obtain the porous substrate reinforced anion exchange membrane. And removing the solvent to obtain the product. According to the method, the porous substrate can be well infiltrated by the cationic polymer solution without pre-treating the porous substrate, so that the porous substrate reinforced anion exchange membrane with a sandwich-like structure is obtained. The film has outstanding swelling resistance and excellent mechanical properties, has good electrochemical properties, and has good application prospects in alkaline film energy conversion devices.

The invention belongs to the technical field of batteries, and particularly relates to a lithium ferrite lithium supplement agent and a preparation method and application thereof. Compared with the prior art, a solid electrolyte coating layer is formed on the surface of the carbon-doped lithium iron oxide material through a low-temperature molten salt method, so that air can be effectively isolated, the air stability of the material is improved, the lithium removal phenomenon is reduced, and the structural integrity and lithium supplement performance of the material are kept; and the lithium ferrite lithium supplement agent combines the high theoretical lithium supplement capacity of Li5FeO4 and the excellent ionic conductivity of the solid electrolyte, so that the electrochemical performance of the material can be improved while the high lithium supplement capacity is maintained, and a new technical scheme is provided for commercial application of the high-energy-density lithium ion battery.

The invention provides a silicon-carbon composite material as well as a preparation method and application thereof. The silicon-carbon composite material comprises a porous carbon material; the silicon particles are distributed on the surface layer of the porous carbon material and in pore channels in the porous carbon material, the distribution concentration of the silicon particles in the surface layer of the porous carbon material is smaller than that of the silicon particles in the porous carbon material, and the particle size of the silicon particles in the surface layer of the porous carbon material is smaller than that of the silicon particles in the porous carbon material; the silicon dioxide layer is formed on the surface of the silicon particles; and the carbon coating layer is formed on the surface of the silicon dioxide layer. The lithium ion battery prepared by taking the silicon-carbon composite material as a positive electrode active material shows good electrochemical performance, and has relatively high specific capacity, good cycling stability and rate capability.

The invention relates to the technical field of battery materials, and discloses a lithium cobalt oxide composite positive electrode material with a coating layer, a preparation method thereof, a positive electrode and a battery. The lithium cobalt oxide composite positive electrode material with the coating layer comprises a main body and the coating layer coated outside the main body, the chemical formula of the main body is LixNayCo1-zMzO2, x is more than or equal to 0.7 and less than or equal to 0.74, y is more than 0 and less than or equal to 0.1, z is more than or equal to 0 and less than or equal to 0.1, and M is selected from at least one of Al, Mg, W, Ti, La, Zr, Y, Ni, Mn and Nb; the coating layer is a metal oxide; and a crystal phase in the main body is a T2 and O2 composite phase. The preparation method comprises the following steps: firstly preparing a P2-phase sodium cobalt oxide precursor, coating the precursor, and then carrying out ion exchange with a lithium source mixed molten salt to finally obtain the composite positive electrode material of T2 and O2 composite phase lithium cobalt oxide with a coating layer. The positive electrode material has good electrochemical performance.

The invention discloses a method for preparing a composite iron-based polyanion positive electrode material. The structural formula of the positive electrode material is represented as Na4Fe3 (PO4) 2 (P2O7) (at) Camp, mXenes are sodium ferric pyrophosphate compositely coated by an MXenes material and a carbonaceous precursor, and the preparation method comprises the following steps: weighing a sodium source, a ferrous source, a phosphorus source and a carbon source according to a stoichiometric ratio, uniformly mixing, grinding, spray-drying and sintering at high temperature to obtain the composite iron-based polyanion positive electrode material, and the carbon source comprises iron-nickel doped polyethylene glycol. The composite iron-based polyanion positive electrode material provided by the invention is remarkably improved in the aspects of energy density, rate capability and cycle life, and the preparation process is simple to operate, reliable in flow, quick in preparation process and easy for industrial production, so that an ideal scheme is provided for commercialized sodium ion battery positive electrode materials.

The invention relates to the technical field of sodium ion battery positive electrode materials, in particular to a carbon-coated sodium ferric phosphate pyrophosphate positive electrode material and a preparation method and application thereof.The preparation method includes the steps that carbon nanotubes and an organic carbon source serve as carbon sources to prepare two kinds of sodium ferric phosphate pyrophosphate particles, and the two kinds of particles are mixed in proportion and then sintered to obtain the carbon-coated sodium ferric phosphate pyrophosphate positive electrode material. In the carbon layer coated on the surface of the material, the carbon nanotubes and the organic carbon source exert respective conductive advantages to form a strong conductive network, so that the conductivity of the material is improved, and the overall structural rigidity of the material is enhanced.

The invention belongs to the technical field of lithium batteries, and discloses a lithium nickel manganese oxide positive electrode material, a preparation method thereof and a lithium ion battery. Wherein the lithium nickel manganese oxide positive electrode material has a regular truncated octahedron single crystal structure, and the ratio K of a (111) crystal face orientation parameter to a (100) crystal face orientation parameter in an XRD (X-Ray Diffraction) spectrogram of the lithium nickel manganese oxide positive electrode material is 1-1.6. The lithium nickel manganese oxide positive electrode material provided by the invention has excellent rate capability and cycling stability, and can be well applied to production and manufacturing of lithium ion batteries.

The invention provides a high-performance all-solid-state sodium ion battery, and belongs to the technical field of power batteries, the sodium ion battery comprises a Prussian white positive electrode, a metal sodium negative electrode and an NASICON type solid electrolyte; preparation raw materials of the Prussian white positive electrode comprise Prussian white, the general formula of the Prussian white is NaxFe [Fe (CN) 6], and x is larger than or equal to 1.8 and smaller than 2.2; the composition of the NASICON type solid electrolyte is NaxZr2-yMySiuPvO12, x is more than 0 and less than or equal to 4, y is more than or equal to 0 and less than 2, u is more than 0 and v is less than 3; in the NaxZr2-yMySiuPvO12, M is at least one of a Zn element, a Mg element, a Cu element, an Al element, a Ni element, a Ga element, a Fe element and a K element. The sodium ion battery has excellent electrochemical performance at room temperature, is high in safety, and is beneficial to commercialized development and application of all-solid-state sodium ion batteries. The invention also provides a preparation method of the high-performance all-solid-state sodium ion battery.

The invention relates to a full-temperature-range polymer-based solid electrolyte, a solid-state battery and a preparation method. Mixing alkali metal salt, a polymer monomer and a plasticizer to obtain an electrolyte precursor; the polymer monomer comprises a fluorinated acrylate compound; the plasticizer comprises a fluorinated carboxylic ester compound, a fluorinated carbonic ester compound or a fluorinated amide compound; and adding an initiator into the electrolyte precursor, heating and polymerizing to obtain the polymer-based solid electrolyte with the polar functional group forming the dipole group, namely the full-temperature-range polymer-based solid electrolyte. A polymer monomer with a soft long side chain is used, and plasticizer molecules are anchored between polymer chains, so that leakage of the plasticizer molecules and parasitic reaction between the plasticizer molecules and an electrode are reduced, and the interface stability of the electrolyte in a high-temperature environment is improved; a polar functional group in the solid electrolyte has relatively high electronegativity, and the formed dipole interacts with alkali metal ions, so that the ions are quickly decoupled from a polymer matrix, and the low-temperature conductivity is favorably improved.

The invention discloses a ferric sodium pyrophosphate positive electrode material, a preparation method thereof and a battery, and relates to the technical field of batteries. Pre-sintering is performed; sanding and spray drying; and high-temperature sintering. Wherein the pH value of the reaction is controlled by using a Tris-HCl buffer solution in the hydrothermal reaction, so that the precursor is uniformly crystallized and has high crystallinity, and low-temperature segmented presintering is adopted later, so that the compaction density of the material can be controlled, and the related electrical properties of the material are relatively good. In the preparation process, a carbon source and a doping element are supplemented twice, so that carbon coating is uniform in the sintering process, the compaction density of the NFPP positive electrode material is further improved, the properties such as theoretical specific capacity of the positive electrode material are better through doping and carbon coating modification, and the high-compaction and high-capacity ferric sodium pyrophosphate positive electrode material is obtained.

The invention belongs to the technical field of electrochemical energy storage, and relates to a nitrogen-doped MXene loaded VCo double-monatomic catalyst as well as a preparation method and application thereof. The preparation method comprises the following steps: adding a nitrogen-containing precursor into at least one layer of MXene suspension, and uniformly stirring to obtain a suspension; respectively dissolving a cobalt-containing compound and a vanadium-containing compound in water to prepare a cobalt-containing compound solution and a vanadium-containing compound solution, adding the cobalt-containing compound solution and the vanadium-containing compound solution into the suspension, and performing stirring, ultrasonic treatment and crushing to obtain a mixed solution; freeze-drying the mixed solution to obtain a precursor; and carrying out heat treatment on the precursor, and washing, centrifuging and drying the obtained powder to obtain the nitrogen-doped MXene loaded VCo double-monatomic catalyst. According to the invention, VCo double monatomic atoms are anchored on the surface of the few-layer MXene, so that the MXene serving as a sulfur carrier of the room-temperature sodium-sulfur battery can effectively adsorb and catalyze conversion of sodium polysulfide, and the room-temperature sodium-sulfur battery with excellent cycle life and capacity is obtained.

The invention discloses a method for recycling a lithium cobalt oxide positive electrode material in a waste lithium battery through a cascade pyrolysis method, and relates to the technical field of battery positive electrode recycling. The waste lithium battery is subjected to real-time adjustment according to a first-stage temperature adjustment formula within a first-stage pyrolysis temperature range to obtain a first-stage product; calculating a second-stage formula temperature of the first-stage product in a second-stage pyrolysis temperature range according to a second-stage temperature formula, constructing a second-stage temperature control model, and predicting a second-stage real-time prediction temperature; a second-stage product is obtained according to the second-stage formula temperature and the second-stage real-time predicted temperature, a third-stage formula temperature of the second-stage product is calculated according to a third-stage temperature formula in a third-stage pyrolysis temperature range, a third-stage temperature control model is constructed, a third-stage real-time predicted temperature is predicted, and a lithium cobalt oxide product is obtained according to the third-stage formula temperature and the third-stage real-time predicted temperature. The purity and the electrochemical performance of the lithium cobalt oxide positive electrode material are improved, and meanwhile, the energy consumption is reduced.

The invention provides a silicon-carbon negative electrode material, a preparation method thereof and a lithium ion battery. The silicon-carbon negative electrode material comprises a porous carbon substrate, nano silicon deposited on the surface and in pores of the porous carbon substrate, and a conductive polymer layer coated on the surface of the nano silicon, the porous carbon matrix is formed by taking zinc gluconate as a carbon source through high-temperature pyrolysis and carbonization. According to the silicon-carbon negative electrode material, the preparation method thereof and the lithium ion battery provided by the invention, the silicon-carbon negative electrode material has high specific surface area, excellent conductivity and stable cycle performance, and shows excellent cycle stability and relatively high reversible capacity in the charge-discharge process when being used for the lithium ion battery; the energy density and the cycle life of the lithium ion battery are effectively improved, a new technical approach is provided for preparation of the silicon negative electrode material of the lithium ion battery, and the preparation method has a wide application prospect.

The invention discloses a preparation method of a composite sodium iron phosphate positive electrode material with high compaction density, which is characterized by comprising the following steps: (1) mixing a sodium source, an iron source, a phosphorus source, a carbon source and the like for preparing the composite sodium iron phosphate positive electrode material in proportion to obtain a precursor aqueous solution; (2) adding a surfactant into the precursor aqueous solution, grinding and uniformly mixing to obtain a homogeneous precursor aqueous solution; (3) carrying out drying granulation on the homogeneous precursor aqueous solution by using a spray drying technology to obtain composite sodium ferric phosphate precursor particles; and (4) performing high-temperature heat treatment on the composite sodium ferric phosphate precursor particles under the protection of inert gas to obtain the composite sodium ferric phosphate positive electrode material. The sodium-ion battery positive electrode material and the electrode plate with high compaction density can be obtained, the reversible specific capacity of the sodium-ion battery is improved, the problem of low gram capacity exertion is solved, the battery capacity is improved, and high-quality sodium-ion battery supply is provided for the field of energy storage.

The invention relates to a silicon-carbon composite material, a preparation method thereof and a lithium ion battery. The preparation method comprises the following steps: adding porous carbon into a fluidized bed, heating and introducing alkaline mixed gas to obtain amino porous carbon; transferring the amino porous carbon into fluidized bed equipment, vacuumizing, heating, and introducing hydroxyl silane gas for nano silicon deposition; after deposition, introducing ultraviolet light for polymerization and oxidation to obtain a modified silicon-carbon precursor material; transferring the modified silicon-carbon precursor material into a tubular furnace, introducing inert gas to discharge air in the tube, and performing first carbonization to obtain a silicon-carbon material; and adding the resin into an organic solvent, adding the fast ion conductor and the silicon carbon material to be uniformly dispersed, performing spray drying, and performing secondary carbonization to obtain the fast ion conductor coated silicon carbon composite material. The preparation method provided by the invention is simple and efficient, and the prepared silicon-carbon composite material can improve the fast charging performance and is suitable for a negative electrode material of a high-energy-density lithium ion battery.

The invention belongs to the field of lithium ion batteries, and discloses a carbon-coated nanotube lithium titanate / carbon composite negative electrode material, a preparation method and a lithium ion battery. The lithium titanate / carbon composite negative electrode material is of a unique nanotube structure, the structure is composed of nanoparticles which are connected with one another and are covered with carbon layers on the surfaces, and certain gaps are formed among the nanoparticles. The preparation method comprises the following steps: dissolving a carbon source and hexadecyl trimethyl ammonium bromide in an organic solvent, then respectively adding the carbon source and a lithium source according to the proportion, and carrying out solvothermal reaction after fully stirring; and washing, drying and calcining the precipitate obtained after the reaction at high temperature to obtain the lithium titanate / carbon compound. Benefited from the synergistic interaction mechanism of the lithium titanate and the carbon material, the electron / ion transmission kinetics in the charge-discharge process of the lithium titanate / carbon compound is greatly improved, so that the lithium titanate / carbon compound has excellent rate capability and cycle performance. The method has the characteristics of simple process, environment friendliness, low cost, high efficiency and the like.

The invention belongs to the technical field of battery materials, and discloses modified asphalt-based hard carbon as well as a preparation method and application thereof. The preparation method comprises the following steps: mixing asphalt and a nitrogen-containing compound, carrying out a first heating reaction in a protective gas atmosphere, cooling, and carrying out a second heating reaction to obtain doped asphalt, carrying out oxidation treatment on the doped asphalt to obtain an oxidized material; and carrying out pre-carbonization and carbonization treatment on the oxidized material in a protective gas atmosphere to obtain the modified asphalt-based hard carbon. The doping of the gradient heating nitrogen element is beneficial to the construction of a three-dimensional conductive network and a flexible skeleton, and the conductivity and the structural stability of the modified asphalt-based hard carbon are enhanced, so that the electrochemical performance of the modified asphalt-based hard carbon is improved.

The invention provides a preparation method of a lithium manganese iron phosphate composite material containing an MXene coating layer, and the method comprises the following steps: uniformly dispersing manganese salt, ferric salt, phosphorus salt and lithium salt solutions and an antioxidant in a dispersing agent respectively, and mixing to obtain a mixed solution; carrying out ultrasonic treatment on the mixed solution in a protective atmosphere to obtain a lithium manganese iron phosphate dispersion liquid; carrying out solid-liquid separation on the lithium manganese iron phosphate dispersion liquid, washing with water, and drying in a drying oven at a set temperature; calcining the lithium manganese iron phosphate solid, and cooling to room temperature to obtain a lithium manganese iron phosphate body material; the preparation method comprises the following steps: preparing a dispersion liquid from a lithium manganese iron phosphate body material, uniformly mixing the dispersion liquid with an MXene dispersion liquid, coating the outer surface of the lithium manganese iron phosphate body material with MXene under ultrasonic waves, and then filtering and freeze-drying to obtain the lithium manganese iron phosphate composite material. According to the lithium manganese iron phosphate composite material prepared by the invention, the conductivity of the material is effectively improved, and meanwhile, dissolution of manganese ions in the material can also be inhibited.

The invention discloses a rechargeable magnesium battery composite electrolyte and a preparation method and application thereof, the electrolyte comprises an organic ether solvent, an electrolyte magnesium salt and an additive, and the additive is one or two of a sulfimide additive or a phosphate additive. By introducing the sulfimide additive into the organic ether solvent electrolyte containing the electrolyte magnesium salt, the kinetic performance of the electrolyte is remarkably improved under the mutual synergistic effect of all the components, the solvation structure of electrolyte magnesium ions is effectively regulated and controlled, the dissolution of the electrolyte magnesium salt is accelerated, the conductivity of the magnesium ions is improved, and the service life of the electrolyte is prolonged. Reversible electrochemical circulation of the magnesium symmetric battery under high current density is realized, the cycle life of the battery is prolonged, a phosphate ester additive is continuously introduced, a phosphorus-rich magnesium ion conductive interface film is formed on the surface of magnesium metal, the transmission capacity of Mg < 2 + > is enhanced, the overpotential and potential barrier of magnesium negative electrode dissolution / deposition are reduced, and the performance of the battery is improved. Therefore, the electrochemical reversibility and coulombic efficiency of the asymmetric battery are improved.

The invention discloses a short-process preparation method and application of a vanadyl sulfate electrolyte based on vanadium slag valence regulation and control, and belongs to the technical field of vanadium electrolytes. The method comprises the following steps: leaching the vanadium slag by using sulfuric acid to obtain a leaching solution containing low-valence vanadium; extracting vanadium and chromium in the leachate by adopting an amine organic extraction agent; carrying out reverse extraction by using sulfuric acid; the method comprises the following steps of: firstly, extracting and separating vanadium by using a phosphoric acid extracting agent, and finally, carrying out reverse extraction by using sulfuric acid to obtain the vanadium electrolyte which can be used for constructing a VFB-5kW / 10kWh vanadium battery energy storage system. The traditional established thinking that pentavalent vanadium is extracted through vanadium slag oxidation to serve as a vanadium source to prepare the vanadium electrolyte is broken through, the novel technology for extracting the low-valence vanadium solution from the vanadium slag to directly prepare the vanadium electrolyte is provided, the short-process and green novel technology for preparing the vanadium electrolyte from the vanadium slag is constructed, the efficiency of the vanadium electrolyte preparation technology is improved, and the preparation cost is reduced.

The invention provides an ionic liquid additive for a solid-state lithium metal battery electrolyte and a method for preparing the solid-state lithium metal battery electrolyte by using the ionic liquid additive. The bistrifluoromethanesulfonyl imide salt containing terphenyl and lithium carboxylate obtained through Michael addition reaction is captured by open metal sites of the MOF material UiO-66-NH2, the structural stability of the material can be improved, more transmission channels are provided for lithium ions, and therefore the transference number of the lithium ions is increased, the performance of the lithium metal battery is improved, and the service life of the lithium metal battery is prolonged. Especially in the aspect of charge and discharge rate. The electrolyte material disclosed by the invention has good stability with lithium metal, so that electrolyte decomposition can be prevented, and an unstable phenomenon, such as lithium dendrite growth, on the surface of an electrode can be avoided, so that a lithium metal battery can show excellent electrochemical performance, including better cycling stability, high coulombic efficiency and longer battery life.

The invention provides an electrolyte for improving the interface stability of a four-electron aqueous zinc-iodine battery, and belongs to the technical field of zinc-iodine battery electrolyte additives, the electrolyte comprises N, N-dihydroxyethyl glycine, zinc sulfate, an additive and water; in the electrolyte, the concentration of the N, N-dihydroxyethyl glycine is 0.5 + / -0.2 mol / L; the molar ratio of the additive to the zinc sulfate is 1: 3; the additive comprises any one of methyl triethyl ammonium chloride, betaine hydrochloride and triethylamine hydrobromide. The electrolyte can enhance the interface stability of the electrode electrolyte, improve the cycling stability and electrochemical performance of the aqueous zinc-iodine battery, inhibit side reactions, and improve the safety and reliability of the battery. The invention also provides a high-capacity aqueous zinc-iodine battery.

The invention provides a negative pole piece and a preparation method thereof, a sodium ion battery and electric equipment, and relates to the technical field of sodium ion batteries. The negative pole piece comprises a current collector, a first coating and a second coating, the first coating is arranged between the current collector and the second coating; the raw materials of the first coating comprise hard carbon, first soft carbon, a first conductive agent, a first dispersant and a first binder; the second coating is prepared from the following raw materials: second soft carbon, a second conductive agent, a second dispersing agent and a second binding agent. The negative pole piece has relatively high flexibility, compaction density, electronic conductivity, cycle performance and rate capability, and can also reduce the risk of sodium precipitation and the probability of powder falling.

The invention discloses a preparation method and application of high-dispersion small-particle-size iron phosphate. The method comprises the following steps: 1) dissolving an iron source in a phosphoric acid solution to obtain ferrous dihydrogen phosphate; 2) adding a cellulose additive into the solution obtained in the step 1), stirring and heating; 3) heating to 60-95 DEG C, adding hydrogen peroxide, carrying out oxidation reaction, and aging; and 4) filtering the solvent, washing, drying, and roasting to obtain the iron phosphate. The iron phosphate provided by the invention is in a sheet shape, no agglomeration exists between sheets, the particle size can be as low as 1 micron or below, the grinding efficiency of lithium iron phosphate can be effectively improved, and the electrochemical performance of a lithium battery positive electrode material prepared from the lithium iron phosphate can be effectively improved.

The invention belongs to the technical field of lithium ion batteries, and particularly discloses a lithium ion battery positive electrode material, a preparation method thereof and a lithium ion battery. The lithium ion battery positive electrode material comprises a lithium-rich manganese-based positive electrode material and F-doped ferric cobaltate coating at least part of the surface of the lithium-rich manganese-based positive electrode material, the chemical formula of the F-doped ferric cobaltate is FeCo2O4-0. 5xFx, and x is larger than or equal to 0.01 and smaller than or equal to 0.06. According to the lithium ion battery positive electrode material, the lithium-rich manganese-based positive electrode material is coated with FeCo2O4-0. 5xFx, the structural stability of the lithium-rich manganese-based positive electrode material can be effectively improved, the FeCo2O4-0. 5xFx coating layer has a high Fermi level and excellent conductivity, and the ionic conductivity of the lithium-rich manganese-based material can be effectively improved.