109results about How to "Excellent long cycle performance" patented technology

Drug-containing nanoparticles are provided that enable effective targeting and sustained-release of a water-soluble, non-peptide, low-molecular weight drug and cause reduced accumulation of the drug in the liver. The nanoparticles containing a water-soluble, non-peptide, low-molecular weight drug are obtained by hydrophobicizing the water-soluble, non-peptide, low-molecular weight drug by a metal ion, and reacting the hydrophobicized drug with a poly(lactic acid)-polyethylene glycol block copolymer or a poly(lactic-co-glycolic acid)-polyethylene glycol block copolymer. The nanoparticles have favorable targeting and sustained-release properties and cause reduced accumulation of the drug in the liver.

The invention discloses an organic-inorganic composite solid electrolyte. The solid electrolyte is characterized by being prepared from an acrylate material, lithium salt, a crosslinking agent, an initiator, a plasticizer, a fast ionic conductor and a porous rigid support material. The preparation method of the inorganic composite solid electrolyte is characterized by comprising steps as follows:mixing the acrylate material with the lithium salt to completely dissolve the lithium salt in acrylate; adding the crosslinking agent and the plasticizer to the mixed solution, and stirring the mixture evenly; adding the fast ionic conductor to the mixed solution, and performing ultrasonic treatment or stirring to disperse the conductor uniformly; adding the initiator to the mixed solution, and performing stirring uniformly; uniformly pouring the mixed solution on the porous rigid support material; performing heating initiation at 60-100 DEG C to enable the acrylate material to be copolymerized with the crosslinking agent to obtain the organic-inorganic composite solid electrolyte. The solid electrolyte has the advantages that the preparation method is simple, the production efficiency ishigh, and the assembled solid lithium battery has lower impedance and higher capacity.

The invention discloses lithium secondary battery overcharge protection electrolyte and a lithium secondary battery. The electrolyte contains electrolyte lithium salts, non-water organic solvents, film forming additives and overcharge protection additives, wherein the film forming additives are at least one kind of materials from TMSP (tris(trimethylsilyl) phosphate) and DTD (dioxathiolane 2,2-dioxide); the overcharge protection additives comprise oxidation and reduction shuttle type overcharge protection additives. The overcharge protection additives used in the electrolyte do not take part in any reaction process at the normal work voltage of 2.75 to 4.35V; when the battery charging voltage exceeds 4.4V, the oxidation and reduction shuttle type overcharge protection additives generate oxidation and reduction shuttle current distribution and voltage limitation on the surface of an electrode; the voltage is controlled to be within a range; the intense decomposition of the electrolyte inside the battery due to too high voltage can be avoided; further, the occurrence of safety problems of combustion, explosion and the like of the battery can be prevented.

The invention relates to a three-dimensional graded carbon-clad NaTi<2>(PO<4>)<3> / C micrometer flower electrode material and a preparation method and application thereof. The diameter of the three-dimensional graded carbon-clad NaTi<2>(PO<4>)<3> / C micrometer flower electrode material is 5-10 micrometers, the thickness of a carbon-clad NaTi<2>(PO<4>)<3> / C nanosheet subunit is only 1-5 nanometers, mesopores with pore diameters of 2-30 nanometers are formed in the carbon-clad NaTi<2>(PO<4>)<3> / C nanosheet subunit, the thickness of a surface carbon layer is 2-5 nanometers, and the nanosheet subunits are in over joint to form a three-dimensional conductive network. The three-dimensional graded carbon-clad NaTi<2>(PO<4>)<3> / C micrometer flower electrode material has the advantages that the three-dimensional graded carbon-clad NaTi<2>(PO<4>)<3> / C micrometer flower is prepared by a simple and practical solovothermal method combined with a high-temperature calcination method, and is endowed with excellent high rate performance and stable long-circulation capability when taken as a positive electrode active material of a sodium ion battery. The process is simple, the three-dimensional graded carbon-clad NaTi<2>(PO<4>)<3> / C micrometer flower electrode material is high in practicable and is high in safety coefficient, the requirement on a device is low due to the adoption of the solovothermal method and the calcination processing, production can be expanded, and market promotion is promoted.

The invention discloses a non-aqueous electrolyte of a high-nickel ternary lithium ion battery and a high-nickel ternary lithium ion battery containing the electrolyte, which relates to the technicalfield of lithium ion batteries. The high nickel ternary lithium ion battery electrolyte comprises an electrolyte lithium salt, a non-aqueous organic solvent and a film forming additive. The film forming additive comprises vinyl sulfate and a phosphate ester compound having a structure of formula (I), optionally further comprising a conventional negative electrode film forming additive. The phosphate ester additive can form a protective film on the surface of the positive electrode material, thereby avoiding the generation of cracks in the NCM particles during the circulation process, reducingthe dissolution of transition metal elements at high temperature, and improving the normal temperature circulation performance, high temperature circulation performance and high temperature storage performance of the battery.

The invention discloses a thick electrode with excellent electrochemical performance. An electrode thickness of the thick electrode is larger than 300mu m. The thick electrode comprises an anode thick electrode body and a cathode thick electrode body, wherein the anode thick electrode body comprises an anode current collector, an anode active material, an anode binder, a porous carbon conductive agent and a fluorocarbon surfactant; the cathode thick electrode body comprises a cathode current collector, a cathode active material, a cathode binder, a porous carbon conductive agent and a thickener; the porous carbon conductive agent has rich porous channels, can obviously absorb and keep electrolyte and solves the problems that thick electrode electrolyte has poor wettability, active material utilization is insufficient, and the like; the fluorocarbon surfactant can reduce surface tension of anode slurry, improve a coating effect of the slurry on the current collectors and meanwhile improve absorbing and keeping ability of an anode piece to the electrolyte. By means of the technical characteristics, the anode thick electrode body and the cathode thick electrode body with excellent conducting performance can be prepared out, so that a high energy density lithium ion battery with excellent electrochemical performance can be obtained.

The invention relates to a tumor-targeted T1-T2 double nuclear magnetic resonance imaging contrast agent and a preparation method and an application thereof. The contrast agent comprises hyaluronic acid-coated ferroferric oxide composite magnetic nanoparticles, wherein the molecular formula of hyaluronic acid is as shown in the specification; n is an integer of 17-290. The preparation method of the contrast agent comprises the following steps: (1) dissolving hyaluronic acid into deionized water, introducing a gas, and heating to obtain a reaction system A; (2) dissolving ferric salt and ferrous salt into a strong acid to obtain a solution B; (3) injecting the solution B into the reaction system A, adjusting the pH to be alkaline, and then refluxing at a high temperature to obtain a reaction system C; and (4) cooling a reaction system C to a room temperature, and dialyzing to obtain the contrast agent. The invention further provides an application of the contrast agent in T1 and T2 weighted imaging in in-vivo and in-vitro nuclear magnetic resonance. The contrast agent provided by the invention has superparamagnetism and outstanding T1 and T2 relaxation enhancement effects, and is suitable for being used as a T1-T2 double nuclear magnetic resonance imaging contrast agent.

The invention discloses lithium secondary battery electrolyte, a preparation method of the lithium secondary battery electrolyte as well as a lithium secondary battery. The lithium secondary battery electrolyte comprises a non-aqueous organic solvent, electrolyte lithium salt and an additive; the non-aqueous organic solvent comprises carbonic ester and carboxylic ester; the electrolyte also comprises fluoroalkyl boric acid ester with the structural formula of (R1O)B(OR2)(OR3), wherein R1, R2 and R3 are alkyl group or alkyl group containing flourine with the number of carbon atoms being 1 to 10. Fluoroalkyl boric acid ester has favorable oxidation resistance, surface active performance and film forming performance; proper amount of fluoroalkyl boric acid ester is added into the electrolyte, and the liquid injection processing property, the circulation performance and the high-voltage-resistant performance of the lithium secondary battery are improved.

The invention relates to the technical field of lithium ion batteries, and discloses non-aqueous electrolyte for ternary lithium ion batteries and a nickelic lithium ion battery comprising the electrolyte. The non-aqueous electrolyte for ternary lithium ion batteries comprises electrolyte lithium salt, a non-aqueous organic solvent and a film-forming additive, wherein the film-forming additive comprises a compound with a structure in formula (I). The additive with the structure in formula (I) is capable of forming uniform and compact protection films on the surfaces of ternary materials, so asto decrease oxidation reaction of the electrolyte on the surfaces of battery materials; the formed SEI films are stable and compact, so that the increase of AC impedance of the batteries in the cycling process is decreased and the cycling performance of the batteries is improved; and the HOMO energy of the films is slightly higher than ethylene carbonate, so that the films can be oxidized and decomposed on the surfaces of anodes in prior to ethylene carbonate, thereby inhibiting the decomposition reaction of the electrolyte solvent and playing a positive role in enhancing the cycling performance of NCM / graphite batteries at a high temperature of 45 DEG C.

The invention discloses an aluminum clad manganese-base laminated composite lithium ion battery cathode material and a preparation method thereof. According to the anode material, aluminum salt is coated on an outer surface of a manganese-base cathode material with a laminated structure in a chemical formula of Li(LixMn1-y-zM1yM2z)O2. The preparation method comprises the following steps of: (1) preparing a mixture; (2) sintering and treating powder; (3) preparing a corresponding amount of soluble aluminum salt, adding the soluble aluminum salt into the manganese-base laminated cathode material, and uniformly stirring; (4) preparing a NH3.H2O solution, a NH4F solution or a NH4H2PO4 solution, adding the solution into slurry of aluminum nitrate and the manganese-base laminated cathode material, and uniformly stirring; and (5) drying the slurry obtained in the step (4), and sintering at the temperature of between 400 and 800 DEG C for 5 to 15 hours. The aluminum clad manganese-base laminated composite lithium ion battery cathode material has high capacity, low first charging voltage platform and excellent long cycle performance, takes an Mn element as a basis, and is low in raw material cost and particularly suitable for preparing large batteries such as batteries of electric vehicles.

The invention belongs to the technical field of lithium ion batteries, particularly to a non-aqueous electrolyte and a lithium ion battery containing the same. The non-aqueous electrolyte comprises alithium salt, a non-aqueous organic solvent and additives, and the additives comprise a compound additive A having a structure represented by a formula I, a compound additive B having a structure represented by a formula II, and a film forming additive. Compared with the prior art, the non-aqueous electrolyte for the lithium ion battery, through the synergistic effect of the compound additive A, the compound additive B, the film-forming additive and a lithium salt additive, has excellent film-forming performance on the surface of the electrode, effectively improves the thermal shock performance of the lithium ion battery, has good cycle performance, can effectively improve the high-temperature storage performance, and gives consideration to the dynamic performance of the lithium ion battery.

The invention discloses a non-aqueous electrolyte for a high-temperature resistant lithium ion battery and relates to the technical field of lithium ion batteries. The non-aqueous electrolyte of the high-temperature-resistant lithium ion battery contains an electrolyte lithium salt, a non-aqueous organic solvent and a film-forming additive, wherein the film-forming additive contains a negative electrode film-forming additive and a high-temperature additive, and the high-temperature additive is one or more of methylene methane disulfonate, 1,3-propane sultone, citraconic anhydride, adiponitrile, succinic anhydride, maleic anhydride, 1-propylphosphonic anhydride and vinyl ethylene carbonate. The non-aqueous electrolyte for the high-temperature resistant lithium ion battery effectively improves high-temperature (85 DEG C) storage performance and high-temperature (80 DEG C) cycle stability of the lithium ion battery. On the basis of the additive and the non-aqueous organic solvent, the high-temperature performance and long cycle performance of the power battery can be improved only the conventional lithium salt LiPF6, the cost is low, and the electrolyte is conductive to industrialization.

The invention discloses a preparation method of a high-nickel positive electrode material, which comprises the following steps: uniformly mixing up a Ni-containing hydroxide, a lithium-containing compound and a doping element, and calcining to obtain a base material A after the mixing operation; adding the base material A into a washing solution, controlling the temperature of the washing solution, washing away residual lithium carbonate and lithium hydroxide on the surface, adding a lithium-containing compound into the washing solution, and drying the washed base material to obtain a mixtureB; uniformly mixing the mixture B, a coating element and a lithium-containing compound, calcining, and crushing to obtain the finally modified high-nickel positive electrode material. The high-temperature stability of the nickel material is improved through doping. The residual lithium carbonate and lithium hydroxide on the surface are reduced through washing. The water absorption and processing performance of the material is improved. The damage to the surface of the material during washing can be repaired through coating. The direct contact between the positive electrode material and the electrolyte can be reduced, so that the high-temperature characteristic and long-cycle performance of the battery cell are improved.

The invention discloses an electrolyte for improving the low temperature performance of a lithium ion battery and a lithium ion battery comprising the same. The electrolyte comprises conductive lithium salt, a non-aqueous organic solvent, and additives, wherein the additives include a conventional negative electrode film forming additive, an additive with the structure of Formula I, and an anhydride-type compound additive with the structure of Formula II. According to the battery electrolyte provided by the invention, under synergistic effects among the additive with the structure of Formula I, the anhydride-type compound additive with the structure of Formula II, a nitrogen-containing lithium salt type additive and the conventional negative electrode film forming additive, the electrolytethus has excellent film forming performance on the electrode surface, the cycle performance and the rate performance of the lithium ion battery in a low temperature condition can be effectively improved, and the high temperature cycle performance and the storage performance of the battery are little affected.

The invention discloses a preparation method of cubic nanometer zinc-tin sulfide for a negative electrode material of a sodium ion battery. The preparation method comprises the following steps: weighing a zinc source and a tin source with certain stoichiometric ratios, dissolving the zinc source in deionized water and dissolving the tin source in absolute ethyl alcohol, mixing the obtained two solutions under a condition of room temperature and magnetic stirring after particles are completely dissolved, carrying out stirring until a uniform and clear solution is formed, then adding a sodium hydroxide solution with a certain molar concentration, using a formed sodium chloride template as a guiding agent and an inducer to enable the zinc source and the tin source to form a zinc-tin compoundwith uniform components and a cubic structure, and carrying out centrifugation and drying to obtain a zinc-tin compound precursor, then carrying out vulcanization treatment on the precursor in a reducing atmosphere, and naturally carrying out cooling to room temperature to obtain the cubic zinc-tin sulfide for the negative electrode material of the sodium ion battery. The preparation method disclosed by the invention is short in process flow and simple in equipment, has cheap and easily available raw materials, and is environmentally friendly, and cubic zinc-tin sulfide particles with different micro-scales can be obtained by adjusting corresponding process parameters.

The invention relates to an alkyl silicyl lithium battery polymer electrolyte resistant to high voltage, a preparation method and application of the electrolyte in a lithium battery. The electrolyte comprises alkyl silicyl polymers, lithium salt, a porous supporting material and additives. Experiments show that the alkyl silicyl polymer electrolyte material has good film forming property and the mechanical strength is 0.5-300MPa; an electrochemical window of the electrolyte material is higher than 4.3V, and the electrolyte material has good compatibility with a high voltage cathode material; ionic conductivity at room temperature is 1*10<-5>S*cm<-1>-10<-3> S*cm<-1>, and a battery assembled by adopting the electrolyte material has excellent long cycle performance. The alkyl silicyl lithiumbattery polymer provided by the invention can be taken as a high-voltage-resistant electrolyte material. The invention also provides a preparation method of the polymer electrolyte and electrochemicalproperties of an all-solid-state lithium battery assembled by adopting the electrolyte provided by the invention.

The invention discloses a double-layer coated core-shell negative electrode material for lithium ion battery and a preparation method thereof. A CVD deposition method is used for depositing nano silicon on that graphite particle to obtain a precursor of a negative electrode material; The titanium dioxide, the lithium carbonate and the organic pyrolysis carbon source are dispersed in an organic solvent to prepare a gel; the precursor of anode material was added into the gel, and the core-shell structure anode material was prepared by low temperature treatment, homogeneous dispersion and high temperature reaction. The core of double-layer coated core-shell negative electrode material for the lithium ion battery is nano silicon and graphite, the nano silicon is deposited on the surface of graphite particles, the outer shell is an organic pyrolytic carbon layer, and the inner shell is formed by attaching lithium titanate to the inner wall of the organic pyrolytic carbon layer. The core-shell negative electrode material has high capacity, high rate and excellent cycling performance, and the preparation process is simple, green and pollution-free, suitable for large-scale production.

The invention discloses a cobalt-doped molybdenum sulfide-graphene-carbon composite material, and a preparation method and application thereof. The method comprises proportionally adding cobalt salt,sodium molybdate, a graphene oxide aqueous solution and thiourea into an aqueous solution of sugar; uniformly ultrasonically mixing the mixture; transferring the mixed solution to a hydrothermal reaction kettle for a hydrothermal reaction at a fixed temperature; and obtaining the cobalt-doped molybdenum sulfide-graphene-carbon composite material by washing, drying and sintering. The invention alsodiscloses the composite material and the application thereof. The method, based on the characteristic of the molybdenum sulfide used as a sodium battery negative electrode material, uses the grapheneand carbon having excellent electrical conductivity as a composite medium, utilizes cobalt doping to greatly improve electronic conductivity and sodium storage capacity of the composite material, andprepares the molybdenum sulfide-based composite electrode material having a high specific capacity and a long cycle life in one step. The material is cheap in raw materials, simple in operation process, high in yield, excellent in charge and discharge performance, convenient for industrial production, and easy to promote.

The invention belongs to the technical field of lithium ion batteries, and particularly relates to a battery electrolyte additive, an electrolyte containing the additive and application of the electrolyte. The lithium ion battery electrolyte additive provided by the invention consists of a fluorosulfonic acid compound with a structural formula I and a cyclic acid anhydride compound with a structural formula II, and the electrolyte comprises an electrolyte lithium salt, a non-aqueous organic solvent and the additive, wherein the additive contains a negative electrode film-forming additive, thefluorosulfonic acid compound with the structural formula I and an acid anhydride compound with the structural formula II. The fluorosulfonic acid compound with the structural formula I and the acid anhydride compound with the structural formula II can form a stable and compact interface protection film on the surface of a positive electrode material; dissolution of metal ions in the positive electrode material under the high-temperature condition is inhibited, the high and low temperature performance, the rate capability, the cycle performance and the service life of the lithium ion battery are effectively improved, and the problem that the temperature performance of the battery cannot be considered in the prior art is well solved.

The invention belongs to the technical field of lithium-ion batteries, and particularly discloses a titanium lithium silicate anode material for a lithium-ion battery and a preparation method and an application of the titanium lithium silicate anode material. The lithium-ion battery anode material disclosed by the invention comprises a titanium lithium silicate material, a titanium lithium silicate-based ion-doped compound and an ion-doped titanium lithium silicate material, wherein the titanium lithium silicate material is subjected to coating treatment; the ion-doped titanium lithium silicate material is also subjected to coating treatment; a main body of the anode material is an inorganic salt of titanium lithium silicate; and the chemical formula is Li2TiSiO5. According to the titanium lithium silicate material prepared by the method, the energy density is higher than that of the traditional titanium lithium silicate material; the working voltage is lower than that of lithium titanate; the titanium lithium silicate material has the characteristics of high capacity density and high power density; and the material has a stable structure and good cycle performance, and is a novel anode material for the lithium-ion battery with a good application prospect after inheriting existing anode materials such as lithium titanate and graphite.

The invention relates to a sodium ion battery layered positive electrode material, a preparation method and an application thereof, wherein the sodium ion battery layered positive electrode material is NaNi<0.5-x-y>B<x>C<y>Mn<0.5-z>A<z>O<2>, A is selected from one of Sn, Ti, Nb, Sb and Bi, and z is greater than or equal to 0.02 and less than or equal to 0.08; wherein B is selected from one of Cu or Li, and x is greater than or equal to 0.05 and less than or equal to 0.15; wherein C is selected from one of Mg, Ca and Ba, and y is greater than or equal to 0.05 and less than or equal to 0.12. According to the positive electrode material prepared by the invention, the original Ni site is replaced by the metal, which has the same valence state or lower valence state and is not easy to oxidize,so that the structural stability of the layered positive electrode material with the replaced Ni site is better, and the prepared battery has excellent long-cycle performance and transmission dynamicperformance. The positive electrode material prepared by the invention has good rate capability and cycling stability. The preparation method of the cathode material is simple, environment-friendly, pollution-free and suitable for large-scale production.

The invention relates to an imaging agent. The imaging agent is characterized by comprising IR820-CSQ-Fe nanoparticles, wherein the IR820-CSQ-Fe nanoparticles comprises Fe3O4 coated with an A-X-B structure, wherein A is chitosan quaternary ammonium salt CSQadopting a structure shown as a formula (I), and n is an integer ranging from 17 to 290; B is new indocyanine green IR820 adopting a structure shown as a formula (II); X is a compound adopting a structure shown as a formula (III), and R is an alkylene group. The imaging agent has the advantages of superparamagnetism, outstanding T1 and T2 relaxation enhancement effect, photoacoustic imaging capacity, obvious fluorescence spectra, small and uniform particle size, good penetrability, avoidance of obvious cytotoxicity, good biocompatibility and better long circulation effect; a preparation method is simple, mild in condition and lower in cost; the imaging agent can be freeze-dried and stored for a long time in a solid form.

The invention discloses dual-mode imaging nano-micelle which comprises a CT (Computed tomography) contrast medium, red fluorescent molecules NPAPF (N-(2-naphthyl)phenylamino)phenyl)-fumaronitrile) and a carrying material for carrying the CT contrast medium and the NPAPF into the dual-mode imaging nano-micelle. The invention further discloses a preparation method and an application of the dual-mode imaging nano-micelle. The dual-mode imaging nano-micelle combines fluorescent imaging and CT imaging, achieves targeted dual-mode imaging of living tumor and organs and meanwhile is long in action time, intensive in detection signal and very small in toxicity.

The invention provides a SiO2-coated lithium ion battery positive electrode precursor material and a preparation method thereof, the SiO2-coated lithium ion battery positive electrode precursor material comprises a core and a SiO2 coating layer at least partially coating the surface of the core,a chemical structural formula of the core is NixCoyM1-x-yO, and M is selected from Mn or Al. The SiO2-coated lithium ion battery positive electrode precursor material has the advantages of higher unit metal content, larger specific surface area and the like, so that the lithium mixing effect in the sintering process of the material is better. The prepared positive electrode material is a compound lithium ion positive electrode material with more uniform morphology and better consistency, and is morebeneficial to the long cycle performance and high rate performance of the positive electrode material. The SiO2 coating layer improves the stability of the material, reduces the anisotropic volume change caused by phase change in the cycle process of the battery, and avoids the rupture of the internal structure of secondary particles.

The invention provides a magnetic nanometer diagnosis and treatment agent and a preparation method and application thereof. The magnetic nanometer diagnosis and treatment agent comprises polypyrrole nanoparticles doped with ferroferric oxide nanoparticles and hyaluronic acid adsorbed to the surfaces of the polypyrrole nanoparticles. The nanometer diagnosis and treatment agent is small in grain size, good in penetrability, uniform in grain size, easy to purify, free of obvious cytotoxicity, good in biocompatibility, good in long circulating effect and low in long-term toxicity, and negative charges exist on the surfaces of the particles; an outstanding T2 relaxation enhancement effect is achieved, the linear relation of the T2 relaxation time reciprocal and the iron concentration change within the low concentration range is good, and the nanometer diagnosis and treatment agent has photo-acoustic imaging capability, is an ideal nanometer diagnosis and treatment agent for preparing multi-mode images and is remarkable in photo-thermal and magnetic-thermal treatment effect. The preparation method is simple, conditions are mild, cost is low, and application and popularization are easy.

The invention discloses a soft and hard carbon composite porous negative electrode material for a sodium-ion battery and a preparation method thereof. The soft and hard carbon composite porous negative electrode material is prepared by regulating and controlling cobalt nitrate, dimethylimidazole and polyvinyl alcohol. The preparation method comprises the steps of dropwise adding an ethanol solution of dimethylimidazole into an ethanol solution of cobalt nitrate, and stirring at room temperature to form a precursor ZIF-67 solution; and adding polyvinyl alcohol into the solution, refluxing to form gel, naturally cooling, freeze-drying, and placing in an inert gas atmosphere at 700 to 1100 DEG C for 2 to 5 hours to obtain the negative electrode material. The composite negative electrode material prepared by the invention combines the advantages of excellent conductivity of soft carbon and high capacity of hard carbon, so that the stability of the battery is effectively improved, and the cycle performance and coulombic efficiency of the sodium-ion battery are improved. The method has the advantages of stable raw material components, simple process operation and high repeatability, andis beneficial to industrial production.

The invention relates to a graphite composite material as well as a preparation method and application thereof. The graphite composite material is of a core-shell structure and comprises a secondary particle inner core and a second hard carbon coating layer on the surface of the secondary particle, wherein the secondary particles comprise a plurality of primary particles, and each primary particlecomprises a first hard carbon coating layer. In the graphite composite material provided by the invention, the hard carbon coating layer formed on the surface layer of the primary particle is tightlybonded with the inner core of the particle, no gap exists between the coating layer and the inner core, and the thickness consistency of the coating layer is high; the hard carbon coating layer of the secondary particle shell is beneficial to stabilizing the primary particle accumulation structure, and is beneficial to the long cycle performance of the material; the first hard carbon coating layer formed on the surface layer of the primary particle and the second hard carbon coating layer formed on the surface layer of the secondary particle can accelerate the desolvation process of lithium ions, so that lithium ions can be inserted into graphite more quickly; and according to the graphite composite material, the capacity can be ensured, and meanwhile, the quick charge and cycle performance can be greatly improved.

The invention belongs to the technical field of lithium ion battery electrolytes, and in particular relates to an anti-overcharge electrolyte of a lithium-ion power battery and a lithium-ion power battery, wherein the electrolyte comprises electrolyte lithium salt, a non-aqueous organic solvent, a film-forming additive and an anti-overcharge additive, wherein the film-forming additive is at leastone of tris (trimethylsilane) borate and ethylene sulfate; the anti-overcharge additive is provided with an aromatic compound with a structure (I) formula. The anti-overcharge additive disclosed by the invention does not participate in any reaction process when the battery is at a normal working voltage of (3.0-4.3V); when the charging voltage of the battery exceeds 4.45V, the anti-overcharge additive generates redox flying shuttle shunt voltage limitation on the surface of the electrode to clamp the voltage within a certain range, so as to prevent the internal electrolyte of the battery fromviolently decomposing to generate heat and gas due to excessively high voltage, and further to avoid the battery from the safety problems such as burning, explosion and the like.

The invention discloses a preparation method of a Sb<2>Se<3> composite material used for a lithium-sulfur battery diaphragm. According to the method, rod-like Sb<2>Se<3> is introduced to be used as asupporting framework of a graphene lamination layer, and a coating material structure is modified; Sb<2>Se<3>-pvp and graphene oxide are mixed at a certain proportion, and graphene oxide is reduced through hydrazine hydrate to obtain a dispersion liquid of the Sb<2>Se<3>-pvp and reduced graphene oxide; the dispersion liquid is subjected to spray drying to obtain solid powder, and then the solid powder is glued with a Celgard2400 diaphragm through a binder to prepare a Sb<2>Se<3>-pvp-rGO composite material diaphragm. The electrochemical performance of the lithium-sulfur battery is improved through a simple, convenient and low-cost method.

The invention discloses a high-nickel ternary single crystal material and a preparation method thereof. The preparation method includes the steps that after a material precursor synthesis process is controlled and a precursor is subjected to smashing and grading treatment, the precursor and a lithium source are mixed and then subjected to low-temperature dehydration to obtain a pre-oxide, and thenthe pre-oxide is subjected to high-temperature sintering through a dynamic rotary furnace to obtain the high-nickel ternary single crystal material. Compared with a traditional synthesis method, themethod has the advantages that the internally loose and porous precursor can be rapidly synthesized, the specific surface area of the reaction of the material and the lithium source is increased through crushing and grading, the lithiation ratio of the lithium source to the precursor can be effectively reduced, and the usage amount of the lithium source is reduced; the sintering temperature can bereduced, the sintering time is shortened, the energy consumption is reduced and the production efficiency is improved; and meanwhile, sintered material particles are dispersed uniformly, agglomeration is less, and post-treatment processing is relatively easy. The high-nickel ternary single crystal material prepared by the method has the characteristics of full primary particle form, uniform dispersion, complete crystal form, stable structure, excellent electrochemical performance and the like.