103results about How to "Improve long-cycle performance" patented technology

The invention relates to solid-state electrolytes, in particular to a polycarbonate all-solid-state polymer electrolyte, an all-solid-state secondary lithium battery made of the same and preparation and application thereof. The all-solid-state polymer electrolyte is prepared from polycarbonate macromolecules, lithium salt and a porous supporting material; the thickness is 20-800 micrometers, the mechanical strength is 10-80 MPa, the room temperature ion conductivity is 2*10<-5>S / cm-1*10<-3>S / cm, and the electrochemical window is higher than 4V. The all-solid-state polymer electrolyte is easy to prepare and form, good in mechanical property, high in ion conductivity and wide in electrochemical window; meanwhile, the solid-state electrolyte effectively inhibits growth of negative electrode lithium dendrites and improves interface stability and long circulation performance.

The invention relates to an organic and inorganic composite all-solid-state electrolyte, in particular to an organic polycarbonate macromolecule and inorganic fast-ion conductor composite all-solid-state electrode and preparation and application of an all-solid-state battery formed from the same. The organic and inorganic composite all-solid-state electrolyte comprises polycarbonate macromolecule, an inorganic fast-ion conductor, a lithium salt and a porous rigid support material, the thickness of the organic and inorganic composite all-solid-state electrolyte is 5-2,000 micrometers, the mechanical strength is 2-150MPa, the room-temperature ionic conductivity is 1*10<-4>-6*10<-3> S / cm, and an electrochemical window is greater than 4V. The organic and inorganic composite all-solid-state electrolyte provided by the invention is easy to prepare and simple to form, has favorable mechanical property, and is relatively high in room-temperature ionic conductivity and relatively wide in electrochemical window; and meanwhile, by the organic and inorganic composite all-solid-state electrolyte, the growth of lithium dendrites of a negative electrode can be effectively prevented, the interface stability is improved, and the long-circulation and safe application performance of the battery are further improved.

The invention relates to a low-quality heavy oil and residual oil hydrotreatment combined process. The low-quality heavy oil and residual oil hydrotreatment combined process is characterized in that firstly a heavy oil raw material is subjected to hydrogenation pretreatment by a slurry bed, after the gas-liquid separation is carried out, a liquid product is subjected to hydro-upgrading through a stationary bed, wherein a hydrogenation pretreatment part of the slurry bed comprises a slurry bed hydrogenation reactor and a slurry bed hydrogenation catalyst, reactors used for a hydro-upgrading part of the slurry bed mainly comprise two up-flow deferrization and decalcification reactors connected in parallel, one up-flow demetalization reactor, one fixed bed desulfurization reactor and one stationary bed denitrification reactor sequentially. The low-quality heavy oil and residual oil hydrotreatment combined process has the advantages of being capable of improving the hydrogenation impurity removal capacity of the catalyst, prolonging the life cycle of the catalyst, treating residual oil with high metal content, high sulfur, high nitrogen and high asphaltene and effectively slowing down the ascending velocity of pressure drop of the reactors, so that the long-period operation of the device is realized.

The invention relates to the technical field of lithium ion batteries, in particular to an all-solid-state polymer electrolyte, a preparation method thereof, and an all-solid-state lithium ion battery. The all-solid-state polymer electrolyte comprises lithium salt and a polymer, wherein the polymer is provided with a structure as shown in the general formula (I). The all-solid-state polymer electrolyte provided by the invention achieves high compatibility with the lithium salt, excellent film-forming performance, a Young modulus of 3.9GPa, and a breaking strength of 140MPa, and can effectivelyinhibit the growth of cathode lithium dendrites and pulverization; the ionic conductivity at the room temperature is (0.1-3) x 10<-5>S / cm; and when the all-solid-state polymer electrolyte is used asan electrolyte for the all-solid-state lithium ion battery, the possible safety problems of a liquid-state electrolyte can be avoided, so that the safety performance of the lithium ion battery can begreatly improved.

The invention relates to a solid polymer electrolyte , in particular to a solid electrolyte containing a polymer with a main chain containing sulfur, a solid secondary lithium battery formed by the solid electrolyte as well as a preparation method and application of the solid electrolyte. The solid electrolyte comprises the polymer with the main chain containing sulfur, lithium salt and a porous supporting material; the thickness of the solid electrolyte is 20-800 microns, the mechanical strength of the solid electrolyte is 10-80MPa, the room-temperature ionic conductivity of the solid electrolyte is 5*10<-5>-7*10<-4>S / cm, and the electrochemical window of the solid electrolyte is 4.5-7V. The polymer solid electrolyte provided by the invention is liable to prepare, simple to form and goodin mechanical performance, has higher ionic conductivity and wider electrochemical window at the same time, can effectively inhibit growth of cathode lithium dendrites and can improve the interface stability and the long cycle performance of the battery.

The invention discloses a perforated positive plate of a lithium ion battery. The perforated positive plate comprises a current collector coated with a lithium-iron oxide layer, and active substance layers arranged on upper and lower surfaces of the current collector, wherein uniform diffusion through holes are formed on the active substance layers and the current collector. The preparation methodcomprises the following steps: firstly coating a layer of Li5FeO4 on the aluminum foil surface to provide redundant lithium source for the battery, thereby retarding the lithium ion with the negativepole first effect to form irreversible SEI film consumption and enhancing long circulation performance; secondly, increasing the energy density of the battery by using the positive electrode with high compaction and high surface density; and finally forming a perforated pole plate, wherein the electrolyte can sufficiently enter the internal of the active substance to increase the infiltration ofthe electrolyte and retarding the expansion of the active substance, and the perforated positive plate can be applied in the battery industrialization in large scale. The conventional perforated aluminum foil is obtained by coating after perforating, and the perforated positive plate is obtained by perforating after coating, so that the surface density of the active substance is higher, and the energy density of the battery is 30% higher in relative to the conventional perforated pole plate.

The invention relates to the field of pharmacy and provides a preparation method of targeting and photo-thermal integrated erythrocyte bionic nanoparticles. The method comprises the following steps: firstly, extracting erythrocyte membranes, then loading indocyanine green to a polylactic acid-hydroxyl acetic acid solution, burying adriamycin amycin to the system, and preparing an indocyanine greenpolylactic acid-hydroxyl acetic acid solution buried with adriamycin amycin through a secondary emulsification-solvent evaporation method; then carrying out a reaction on folic chitosan oligosaccharide and the indocyanine green polylactic acid-hydroxyl acetic acid solution to obtain an adriamycin amycin-folic chitosan oligosaccharide-indocyanine green-polylactic acid-hydroxyl acetic acid solution; and finally, extruding the adriamycin amycin-folic chitosan oligosaccharide-indocyanine green-polylactic acid-hydroxyl acetic acid solution into the erythrocyte membranes to obtain the erythrocyte bionic nanoparticles.

The invention relates to a preparation method of a graphite / Prussian blue composite material. The preparation method comprising that ferrous chloride and sodium ferrocyanide undergo a hydrothermal reaction in an aqueous solution of a surfactant based on a coprecipitation method to produce Prussian blue nanospheres, the Prussian blue nanospheres and graphite oxide are stirred, and the solution is quenched by liquid nitrogen, then is freeze-dried and finally is reduced through hydrazine hydrate. The invention discloses a use of the graphite / Prussian blue composite material as a sodium ion battery positive electrode material. The Prussian blue nanospheres have excellent electrochemical performances. Graphene roll coating further increases the conductivity of the Prussian blue nanospheres and improves the long cycle performance of the Prussian blue nanospheres. The capacity of a sodium ion battery positive electrode prepared from the graphite / Prussian blue composite material is not easy to decay, the magnification performance is good, and after cycle 500 times under current density of 150mAhg<-1>, the capacity is about 110mAhg<-1> and a capacity retention rate is 90.2%.

The invention discloses a rapidly discharged / charged high power lithium ion battery and a manufacturing method thereof. The positive current collector comprises an aluminum foil and a conductive coating. The negative current collector comprises a copper foil and a conductive coating. The diaphragm is a PE material, which is bidirectionally and synchronously stretched, and ceramic oxide is paintedon the surface of the PE material. The anode paste comprises following components in parts by weight: 10 to 35 parts of lithium cobaltate, lithium nickelate, lithium manganate, lithium iron phosphate,lithium manganese phosphate, lithium iron manganese phosphate, or lithium vanadium phosphate, 62 to 81 parts of nickel cobalt lithium manganate, 1 to 3 parts of Ketjen black or carbon nanotube, and 1to 3 parts of graphene or Super-P and modified 1,3-polyvinylidene fluoride. The cathode paste comprises following components in parts by weight: 55 to 75 parts of artificial graphite or meso-phase carbon micro beads, 20.5 to 36 parts of soft carbon or hard carbon, 1 to 2 parts of CMC, 2 to 4 parts of Super-P, and 1.5 to 3 parts of styrene butadiene rubber SBR or polystyrene-acrylate. The providedlithium ion battery can continuously discharge or charge (30C). The 30C constant current charge capacity can account for 70% or more of 1C capacity, and the 30C discharge capacity can account for 90%or more of 1C capacity.

The invention discloses a high-voltage lithium ion battery combined electrolyte additive, an electrolyte and a battery thereof. The high-voltage lithium ion battery combined electrolyte additive provided by the invention is prepared by mixing a compound containing cyclic thioester, a compound containing P-O and Si-O bonds and a compound which does not contain Si-O / P-O bonds but contains B-O bonds,and under a high voltage, a component A is oxidized and decomposed at an interface of a positive electrode to form a stable CEI film and is reduced on a surface of a negative electrode to generate astable SEI film so that efficiency of a battery can be improved; by adding a component B, wettability of the electrolyte to the electrode can be improved, a stable CEI film can be formed on the surface of the positive electrode, and the efficiency of the battery is further increased while the wettability is improved; and through a component C, a B-O-containing interface film can be formed on the surfaces of the positive electrode and the negative electrode, the B-O interface film has high ionic conductivity, an impedance of the battery can be significantly reduced, polarization of the batteryis decreased, and cycle performance is improved.

The invention discloses a core-shell NiO / C porous composite lithium ion battery negative electrode material. The preparation method comprises the following steps: preparing nano NiO particles; carrying out surface modification on nano NiO by using a surface modifier so that the nano NiO particles are uniformly dispersed and beneficial to Mg(OH)2 coating; carrying out gradient temperature treatment by a hydrothermal process to sequentially coat Mg(OH)2 and an amorphous carbon layer on the prepared nano NiO particle surface; and removing the Mg(OH)2 by using hydrochloric acid to form ducts between the NiO particles and carbon layer. The preparation method enhances the electric conductivity of the composite material and ensures the structure stability of the material. In the recycling process, lithium ions are disembedded to prevent NiO from generating powdering aggregation; and elastic expansion space is reserved in the material, thereby avoiding breaking the base material during NiO expansion and enhancing the cycle life. The prepared material provides effective channels for embedding / disembedding of lithium ions, so that the lithium storage characteristic of the NiO material is fully displayed.

The invention relates to an all-solid-state polymer electrolyte, and particularly relates to a polyformaldehyde all-solid-state polymer electrolyte prepared by in-situ ring-opening polymerization andapplication of the polyformaldehyde all-solid-state polymer electrolyte in forming an all-solid-state secondary lithium battery. The all-solid-state polymer electrolyte is prepared by initiating in-situ ring opening polymerization of a trioxymethylene monomer, an additive and a lithium salt to a porous support material through a catalyst, wherein the thickness ranges from 10[mu]m to 800[mu]m; theroom-temperature ionic conductivity ranges from 4*10<-5>S / cm to 8*10<-3>S / cm, and the electrochemical window is not lower than 4.2V. The all-solid-state polymer electrolyte is easy to prepare and simple to form; the mechanical performance is excellent; and the room-temperature ionic conductivity is high. Meanwhile, the all-solid-state polymer electrolyte can effectively inhibit the growth of lithium dendrites and match with a high-voltage positive electrode material, so that the interface stability, the long cycle performance and the energy density are effectively improved.

The invention discloses an HIFU (high intensity focused ultrasound) controlled-release targeted nanometer drug delivery system of brain glioma, and a preparation method and application of the targeted nanometer drug delivery system. The drug delivery system comprises targeting molecules, a drug, a foaming agent and a nano-carrier, wherein the targeting molecules are Angiopep-2 short-peptide, the drug is adriamycin, the foaming agent is perfluorooctane, and the nano-carrier is a high molecular material which is modified by terminal carboxyl and has polylactic acid-glycolic acid copolymer as a main ingredient; the drug and the foaming agent are wrapped and loaded in the nano-carrier together in a wrapping manner; and the targeting molecules are connected to nano-particle surfaces through a covalent linkage manner. The drug delivery system disclosed by the invention can target and highly express the blood brain barrier of an LRP (low-densitylipoprotein receptor-related protein) receptor and brain glioma cells; the accumulation of the drug at a brain glioma position is effectively improved; after the drug is fully accumulated, HIFU irradiation is given to induce the drug to be instantly and fully released at the brain glioma position; the drug concentration in the brain glioma cells is greatly improved; therefore, the treatment effect of the brain glioma is obviously improved; and meanwhile, the toxic and side effect of the drug on normal tissue is effectively reduced.

The invention provides SiOC microspheres, a preparation method thereof and an application of the SiOC microspheres in a lithium ion battery negative electrode material. The method comprises the following steps: firstly, respectively preparing an oil phase and a water phase, wherein the oil phase is a mixed liquid of a precursor liquid, a liquid pore-forming agent and a catalyst, the water phase isa mixed liquid of water and a surfactant, and dropwise adding the oil phase into the water phase to form an oil-in-water emulsion; heating the emulsion in a drying oven, or curing and molding the oilphase by adopting light wave irradiation, interface reaction and the like; and finally, carrying out heat treatment in a protective atmosphere to obtain the SiOC microspheres. Experimental results show that under high current density (3600 mA.g <-1 >), the specific discharge capacity of the SiOC microspheres can reach 402 mA.h <-1 >. G <-1 > after 1000 cycles.

The invention provides a silicon-based composite material for a negative active material, a negative plate and a lithium ion battery. The preparation method comprises the following steps: arranging single-walled carbon nanotubes distributed in a three-dimensional network shape and an optional first conductive agent in a solid electrolyte coating layer; a three-dimensional conductive network can beconstructed on the surfaces of silicon material particles. Due to the establishment of the three-dimensional conductive network, the electron transmission between the silicon material particles and between the silicon material particles and the graphite is enhanced. The smoothness of an electronic channel after silicon expansion is ensured. The electron transmission stability in the circulation process is improved. The utilization rate of silicon is increased, the first utilization rate of the silicon material is increased, the first effect and the battery capacity of a lithium ion battery containing the silicon-based composite material are improved, the SWCNT elasticity is large, the super mechanical property is 100 times that of steel, it is guaranteed that a conductive network is not changed when a silicon negative electrode expands during circulation, circulation attenuation is slowed down, and the circulation performance is improved.

The invention provides a diaphragm and a battery comprising the diaphragm. The diaphragm comprises a diaphragm base layer and a ceramic coating arranged on the first surface of the diaphragm base layer, wherein the ceramic coating comprises ceramic particles, micropores are formed in the surface and / or the interior of the ceramic coating, the porosity of the ceramic coating is 40-80%, and in the micropores, the volume of pores with the pore diameter being 0.1 micrometer or above accounts for 45-90% of the total pore volume, and the volume of pores with the pore diameter being 1.0 micrometer orabove accounts for 40-80% of the total pore volume. According to the invention, a large number of micropores are formed in the surface and / or the interior of a ceramic coating, so that the porosity of a diaphragm is improved so as to improve the battery rate, residual liquid amount, low-temperature discharge and long-cycle performance, and the needling strength, the self-discharge and the safetyperformance of the diaphragm are not influenced.

The invention provides ternary high-nickel electrolyte and a high-nickel anode lithium ion battery containing the electrolyte. The ternary high-nickel electrolyte is characterized by comprising, by weight, 13-15% of lithium salt, 80-85% of a non-aqueous organic solvent and 0.1-5% of an additive; wherein the additive comprises vinylene sulfate, vinylene carbonate, succinonitrile, tris (trimethyl silicon-based) phosphorus, lithium bifluroflavin imide and lithium dioxalate borate; the lithium salt is lithium hexafluorophosphate; the non-aqueous organic solvent comprises a cyclic carbonate compound, dimethyl carbonate and ethoxy pentafluoro tripolyphosphate; the high-nickel anode lithium ion battery containing the ternary high-nickel electrolyte adopts anode slurry prepared from high-nickel ternary anode powder, a conductive agent, a functional composite binder, a solvent N-methyl pyrrolidone to prepare the anode membrane, the high-nickel anode lithium ion battery has excellent normal-temperature cycle performance, high-temperature cycle performance and high-temperature storage service life, and can obviously reduce the gas yield in the high-temperature storage process.

The invention provides a modified aluminosilicate additive for lithium sulfur battery electrolyte and a preparation method thereof, Y-type molecular sieve precursor was prepared by sodium meta-aluminate, sodium hydroxide and sodium silicate, then mesoporous silicate aluminate was obtained by surfactant and acid-base crystallization, finally mesoporous silicate aluminate was modified by organic lithium salt to make organic lithium source enter mesoporous silicate aluminate pores, and mesoporous silicate aluminate particles loaded with lithium were obtained. The additive prepared by the invention has stable structure, Through the adsorption of modified mesoporous aluminosilicate on polysulfide in electrolyte, The polysulfide is immobilized in the solid particles, which effectively solves theproblem that the electrolyte of the existing lithium sulfide battery is difficult to control the dissolution of lithium polysulfide for a long time, inhibits the polysulfide from passing through theelectrolyte through the separator, thereby keeping the negative electrode material from being corroded, improving the capacity stability of the battery, and improving the long-cycle performance of thebattery.

The invention belongs to the technical field of secondary energy-storing batteries, and in particular relates to nonaqueous electrolyte and a magnesium secondary battery of the nonaqueous electrolyte. The nonaqueous electrolyte is a nonaqueous organic solvent, inorganic magnesium salt and organic borane, wherein the molar ratio of the organic borane to the inorganic magnesium salt is (0.2-20):1; and the nonaqueous organic solvent is an ether organic solvent. The magnesium secondary battery is formed by assembling the nonaqueous electrolyte, a positive electrode and a negative electrode. Compared with the existing electrolyte for the magnesium secondary battery, the nonaqueous electrolyte has the advantages that the nonaqueous electrolyte has wider electrochemical stable window (-4.0V vs.Mg) and higher magnesium deposition / solvent coulombic efficiency (99.8%), does not corrode base metal current collectors of stainless steel, aluminum foil and the like, is non-nucleophilic and is easy to prepare. Compared with the traditional magnesium secondary battery, the magnesium secondary battery provided by the invention has higher charging / discharging capacity, rate capability and long circulation property.

The invention discloses a preparation method of slurry for a lithium titanate battery. The method comprises the steps of (1) preparing glue, namely adding a binder and a certain amount of solvent to a stirring tank A and stirring evenly for the first time; (2) carrying out dry mixing of powder, namely adding a conductive agent and an active substance to a stirring tank B according to the designed weight proportion, carrying out full dry mixing and stirring for a certain period of time and adding a certain amount of anhydrous oxalic acid when the active substance is lithium titanate; and (3) adding the glue which is stirred for the first time in the stirring tank A to the stirring tank B and then fully stirring evenly until the viscosity of the slurry is 6,000-10,000mpa.s. Compared with the prior art, the preparation method has the beneficial effects that (1) the steps (1) and (2) of the method can be simultaneously carried out and the preparation time of the slurry can be obviously shortened; and (2) a certain amount of anhydrous oxalic acid is added to the lithium titanate slurry, so that the pH of the slurry can be improved and the long-term cycle performance of the lithium titanate battery can also be improved.

The invention provides a low-temperature high-energy-density long-cycle lithium iron phosphate battery. A doped lithium iron phosphate is adopted as a cathode, the average particle size is 1-5 [mu]m,wherein D50 is 0.5-5[mu]m, D90 is less than or equal to 8[mu]m, and a doped material is boron nitride and carbon fibers or carbon nanotubes; a diaphragm is a base film coated with two or more of nano-scale Al2O3, BaSO4, AlN and BN; and an electrolyte for improving high and low temperature performance is added into an electrolytic solution. The battery monomer battery cell 0.2 discharge capacity islarger than 220mAh, the cycle performance of the battery monomer battery cell is good, the capacity retention rate of the battery cell is more than 80% after the battery cell is cycled for 1500 timesin 0.5C / 0.5C 100% DOD, the capacity retention rate of the battery cell at -20 DEG C is about 80%, the capacity retention rate of the battery cell at-40 DEG C is about 58%, and the thermal stability is good.

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 a battery, and specifically relates to a preparation method of a NiO / MgO / C composite negative electrode material of a lithium ion battery. Nanometer Ni(OH)<2> / Mg(OH)<2> is prepared by adopting a hydrothermal method firstly; and then glucose is taken as a carbon source to perform hydrothermal coating on Ni(OH)<2> / Mg(OH)<2>. By virtue of the prepared NiO / MgO / C composite negative electrode material, NiO agglomeration in charging and discharging of the lithium ion battery can be prevented while the electrochemical performance of the negative electrode of the lithium ion battery can be improved.

The invention relates to preparation and applications of a biologically camouflaged targeting nano drug delivering system for treating ischemic cerebral stroke. The nano drug delivering system is compose of a drug, an inner core drug carrier, a biologically camouflaging shell, and a target finding material, wherein the drug is bilobalide B, the inner core drug carrier is recombinant high density lipoprotein, a drug is physically embedded into the drug carrier to form a drug loaded inner core; the biologically camouflaging shell is a blood platelet membrane, the drug loaded inner core is embedded in the blood platelet membrane in a co-extrusion mode to form a biomimetic drug loaded nano particle; the target finding material is a cerebral ischemia targeting peptide (CITP), and the CITP is used to modify the surface of the biomimetic drug loaded nano particle to form the biologically camouflaged targeting nano drug delivering system. Recombinant high density lipoprotein is used to wrap bilobalide B to form the drug loaded inner core, a blood platelet membrane and a blood platelet with a CITP modified surface are taken as the biomimetic shells to construct a nano particle for treatingischemic cerebral stroke, the circulation time of the nano particle in human body is prolonged, and the nano particle has a good targeting performance.

The invention discloses a lithium ion battery negative electrode material. A preparation method of the lithium ion battery negative electrode material is characterized in that a surfactant is used for performing surface modification treatment on Si particles, so that Mg(OH)2 can easily coat the surface of nanometer Si powder; firstly, the Si particles are dissolved in a hexadecyl benzene sulfonate ammonium bromide water solution; stirring and ultrasound treatment are performed to generate mixed suspension; then, magnesium nitrate, urea and glucose are added into the suspension; stirring is performed for 3h; the completely stirred suspension is poured into a polytetrafluoroethylene reaction kettle and is then put into a homogeneous reactor; the gradient temperature is set for reaction; reaction is firstly performed for 3h at 160 DEG C; next, reaction is performed for 6h at 180 DEG C; and after the reaction completion and cooling, solid materials are washed by deionized water and are dried for 12h at 40 DEG C. The prepared composite material has the advantages that a carbon material with a high electric conductivity and a stable structure is used as a case layer; graphene is introduced, so that the collapse of the electrode material structure can be released; and the ion and electron conductivity of the material is improved to the great degree.

The invention provides a negative plate and a lithium ion battery comprising the same. The negative plate is formed by coating a conductive coating between a negative current collector and a first negative active material layer, so that the contact resistance between the first negative electrode active material layer and the negative electrode current collector can be reduced, the acting force between the first negative electrode active material layer and the negative electrode current collector is improved, peeling of the first negative electrode active material layer is avoided, the buffer coating is coated between the first negative electrode active material layer and the second negative electrode active material layer, the contact resistance between the first negative electrode activematerial layer and the second negative electrode active material layer can be reduced, the acting force between the first negative electrode active material layer and the second negative electrode active material layer is improved, and the transmission rate of ions and electrons is increased; and the surface of the second negative electrode active material layer is coated with the safety coating,so that the volume expansion of the second negative electrode active material layer is further buffered, the lithium dendrites can be prevented from directly piercing the diaphragm to cause internal short circuit, and the safety risk is reduced.

The invention relates to a solid-state electrolyte, particularly to a high-cohesiveness solid-state electrolyte prepared through in-situ curing, and a preparation method thereof, and a secondary lithium battery composed of the solid-state electrolyte, wherein the raw materials of the high-cohesiveness solid-state electrolyte mainly consist of a hydroxyl-terminated oligomer, an isocyanate-terminated compound and a lithium salt, and the high-cohesiveness solid-state electrolyte is prepared by uniformly mixing and stirring the hydroxyl-terminated oligomer, the isocyanate-terminated compound and the lithium salt, adding the mixture into a battery core and carrying out in-situ polymerization and curing under a heating condition. According to the invention, the electrolyte prepared by in-situ curing has high adhesive force, and is cured under heating, so that the positive electrode, the negative electrode and the electrolyte are tightly attached, the interface impedance between the electrolyte and the positive electrode and the interface impedance between the electrolyte and the negative electrode are reduced, and the effect of improving the rate capability and the cycle performance of the battery is achieved; and the preparation process of the solid-state lithium battery is greatly simplified, the interface contact is optimized, the danger caused by dislocation is prevented, and thesafety of the battery is improved.

The invention discloses a lithium ion battery ferrous oxalate composite negative electrode material and a preparation method thereof, and belongs to the technical field of lithium ion battery negativeelectrode materials. The method comprises the following steps: sequentially adding ferric chloride and hexadecyl trimethyl ammonium bromide into deionized water, and stirring until the ferric chloride and the hexadecyl trimethyl ammonium bromide are completely dissolved to obtain a ferric chloride solution; carrying out solvothermal method synthesis to obtain a ferrous oxalate dehydrate material;adding the obtained material into the ferric chloride solution, transferring turbid liquid obtained by ultrasonic treatment into a high-temperature and high-pressure reaction kettle for heating, coating the FeOOH material on the surfaces of ferrous oxalate particles in situ under a hydrothermal condition, sequentially cleaning and centrifugally separating precipitates after the reaction is finished, and drying the precipitates in a vacuum drying oven to obtain a precursor; and sintering the precursor through a vacuum tube furnace under an inert atmosphere condition to obtain a FeOOH surface coated ferrous oxalate composite negative electrode material. The method effectively solves the problems of high irreversible capacity, poor cycle performance and the like of the metal oxalate negativeelectrode material.

The invention provides a silicon-based negative binder which is an amphiphilic block copolymer modified by fluorinated organic acid, and the block copolymer is obtained by the reaction of two different polymers prepared in advance. The binder can effectively suppress the expansion of the silicon-based negative electrode, so that the silicon negative battery exhibits good cycle performance. The preparation method has the advantages of simple synthesis method, simple process and suitability for industrial production.

The invention provides a high-energy-density long-cycle lithium iron phosphate battery. Lithium iron phosphate doped with vanadium, boron, nitrogen and carbon doped is used as a positive active material, doped carbon nanotubes and / or carbon fibers are used as a negative conductive agent, a base membrane is coated with nanoscale TiO2 and BN to form a diaphragm, and a novel lignin binder is used asa binder. According to the invention, 0.2 C discharge capacity of the battery cell of the single battery is greater than or equal to 2300mAh; the cycle performance is excellent; the capacity retentionratio is 78% or above after 1000 times of 0.5 C / 0.5 C 100% DOD cycles of the battery cell; the capacity retention ratio at -20 DEG C is about 83%; the capacity retention ratio at -40 DEG C is about 63%; and the low-temperature use performance is good.