51results about How to "Improved rate cycle performance" patented technology

The invention relates to a preparation method of nano LiFel-xMxPO4/C lithium phosphate composite positive pole material. Lithium dihydrogen phosphate, iron powder, an M element source and an organic carbon source are uniformly mixed in a solvent medium, are treated for 2 to 7h through a high-energy ball mill, have chemical reaction under mechanical activation, and a uniformly dispersed precursor is prepared. The precursor is thermally treated for 2 to 10h at 600 to 800 DEG C under atmosphere protection and cooled to be room temperature, and the nano LiFel-xMxPO4/C lithium phosphate composite positive pole material is prepared. The preparation method has simple and high-efficiency process and the whole process does not produce ammonia, wastewater and other polluting substances, and is applicable to industrial production. The primary particles of the prepared material are nano particles which are uniformly distributed, and the material is characterized by high specific capacity and good rate cycle performance.

The invention discloses a nitrogen-enriched carbon shell cladded nano core-shell-structure carbonaceous carrier as well as a preparation method and application thereof. The carbonaceous carrier comprises a carbonaceous inner core and a nitrogen-enriched carbon shell covering the carbonaceous inner core. The carbonaceous carrier provided by the invention not only has abundant doping amount of a nitrogen element, but also has high polysulfide ion physical and chemical adsorption capabilities and excellent electrochemical stability; when the carbonaceous carrier is applied to a lithium-sulfur battery and is used as a positive electrode of a lithium-sulfur secondary battery, high capacity and rate circulating performance, and ultrahigh electrochemical stability can be kept even if the lithium-sulfur secondary battery is circularly charged and discharged for a long period, so that the whole electrochemical performance of the battery is improved; and meanwhile, a preparation process of the carbonaceous carrier has moderate conditions, low energy consumption and low cost and large-scale production is easy to realize.

The invention discloses a preparation method for an interconnected nanowire core-shell structure material. The preparation method comprises the following steps of: 1) taking a foamy copper sheet with thickness of 0.2-0.5 millimeter as a substrate; 2) cleaning the surface of foamy copper by using an ordinary cleaning method, immersing the foamy copper in hydrochloric acid to remove an oxide, and then drying by using a nitrogen pistol; 3) calcining for 5 hours at 450 DEG C in air, leading the foamy copper to self-catalytically grow a CuO nanowire or other metal oxide nanowire with diameter of about 30 nanometers and length of 7-10 micrometers; 4) depositing amorphous Si(Ge) at 250 DEG C through plasma enhanced chemical vapor deposition (PECVD) to obtain an interconnected nanowire core-shell structure with diameter of about 100-200 nanometers, namely a Si(Ge) shell and a CuO core; 5) reducing the CuO core by using H2 at 400 DEG C to obtain a high-conductivity metallic Cu nanowire, and completing the building of a three-dimensional current collector; and 6) preparing and completing the three-dimensional interconnected metallic nanowire conductive core structure material.

The invention discloses a preparation method of lithium ion battery negative material titanium niobate. The preparation method comprises the following steps: separately dissolving a niobium source and a titanium source into acetic acid, and slowly mixing the niobium source and the titanium source; loading a mixed solution obtained in the previous step into a reaction kettle, and heating to facilitate the reaction; after the reaction kettle is naturally cooled to the room temperature, washing obtained precipitates for multiple times by separately utilizing deionized water and ethanol, and drying in a vacuum drying oven to obtain powder; and roasting the obtained powder to obtain titanium niobate. The preparation method is moderate in conditions, simple in procedures, easy to operate and convenient in industrialized production. The prepared titanium niobate material is in a spherical shape and is relatively small in size, so that the diffusion speed of lithium ions in the material is increased; and when the prepared titanium niobate material is used as a lithium ion battery negative electrode, the charging-discharging specific capacity is relatively high, and the multiplying power cycling performance is excellent.

The invention belongs to the field of lithium ion batteries, and relates to a nickel-containing precursor, a nickel-containing composite material, and preparation methods and applications of the nickel-containing precursor and the nickel-containing composite material. The nickel-containing precursor comprises a nickel-containing seed crystal and primary particles distributed on the outer edge of the nickel-containing seed crystal in a radial direction. The composition of the nickel-containing precursor is represented by the chemical formula Ni<x>Co<y>M (OH)<2>, wherein M is Mn and/or Al, x is larger than or equal to 0.8, y is larger than or equal to 0 and smaller than or equal to 0.2, z is larger than or equal to 0 and smaller than or equal to 0.2, and x, y and z sum to 1. The nickel-containing seed crystal is composed of a primary particle loose inner core and a surface compact layer which are disorderly distributed inside, and has a hollow pore structure inside after solid-phase sintering. The nickel-containing composite material provided by the invention can significantly improve the capacity and rate cycle performance of a positive electrode material of a lithium ion secondary battery, and has wide application prospects.

The invention relates to a synthesizing method of a nano-grade lithium ion battery composite positive electrode material LiMnPO4/C. According to the invention, a lithium source, a phosphorous source, a manganese source and an organic carbon source are well mixed in a solvent medium; the mixture is processed for 2-7h in a high-energy ball mill, and a uniformly dispersed precursor slurry is obtained with the activation effect of mechanical forces; the precursor slurry is subjected to ultrasonic dispersion in a high-boiling-point polyol solvent, and is subjected to a reflux reaction; an obtained product is filtered and washed; and the product is subjected to a heat treatment for 1-10h under inert atmosphere protection and under a temperature of 600-800 DEG C, such that the nano-grade lithium manganese phosphate/carbon (LiMnPO4/C) positive electrode material is obtained. According to the material provided by the invention, primary particles are well distributed nano-particles, and a conductive carbon layer is formed in-situ on the surfaces of the LiMnPO4/C particles. The method provided by the invention is simple and highly efficient. With the method, no pollutant such as ammonia gas or wastewater is produced during the entire process. Therefore, a development requirement of green chemistry is satisfied.

The present invention discloses a sea urchin-like lithium titanate microsphere preparation method, which comprises: adding metal titanium powder to a sodium hydroxide solution, stirring, carrying out a hydrothermal reaction at a temperature of 80-260 DEG C, carrying out centrifugation separation on the obtained precipitate, drying the precipitate to obtain a titanium dioxide precursor, adding a lithium salt and the titanium dioxide precursor to an ethanol and deionized water mixed solution, stirring to obtain an emulsion, carrying out a hydrothermal reaction, carrying out centrifugation separation on the obtained precipitate, drying to obtain white powder, carrying out a calcining heat treatment at a temperature of 300-1000 DEG C, and cooling to a room temperature to obtain the sea urchin-like lithium titanate microsphere. The method of the present invention has the following beneficial effects that: the sea urchin-like lithium titanate microsphere having the micro-nano grading structure is provided, and has characteristics of high discharge specific capacity and excellent rate cycle performance.

The invention relates to the technical field of manufacturing of lithium ion secondary batteries and provides a prismatic lithium ion battery for a hybrid electric vehicle startup power supply and a manufacturing method thereof. The battery comprises a positive plate, a negative plate, a diaphragm, an electrolyte, an insulating bushing and a battery case, wherein the positive plate contains a positive active material, a binding agent, a conductive agent, an aluminum foil and the like; the negative plate comprises a negative active material, a binding agent, a conductive agent, an aluminum foil and the like. A material system is optimized, the positive active material is lithium iron phosphate coated with a composite containing Al2O3-loaded N grapheme; the negative active material is natural graphite coated with a composite containing CuO/Cu-loaded multi-walled carbon nanotubes. The lithium ion battery manufactured under optimum conditions is low in internal resistance, is excellent in multiplying power cycling performance and heavy load discharge performance, and can meet hybrid electric vehicle startup power supply requirements.

The invention discloses a honeycomb porous hard-carbon anode material for a lithium ion battery, a preparation method of the honeycomb porous hard-carbon anode material as well as the lithium ion battery. According to the method, coffee powder is prepared firstly and subjected to low-temperature carbonization in an inert gas, a precursor is prepared and subjected to organic carbon source coating treatment with a solvent and an organic carbon source, material particles are obtained and subjected to high-temperature carbonization, and the honeycomb porous hard-carbon anode material for the lithium ion battery is prepared. The method adopts a simple process and a simple and controllable synthetic route, micro-control of morphology and size of the material is easy, and the prepared honeycomb porous hard-carbon anode material for the lithium ion battery is high in reversible capacity, high in rate property and cycle performance and good in low-temperature performance.

The invention relates to a synthesis method and application of a hard carbon coated sodium ion battery nano composite material, and belongs to the field of sodium battery materials. According to the technical scheme, the preparation method comprises the following steps: weighing LiNO3, NaNO3 and NH4H2PO4 according to a stoichiometric ratio, respectively dissolving the LiNO3, the NaNO3 and the NH4H2PO4 in deionized water, and mixing; ti (OC4H9) 4 is taken according to the stoichiometric ratio and added into a proper amount of ethyl alcohol to be stirred; adding an ethanol solution into the mixed solution of the Li salt and the Na salt, and mixing; adding a proper amount of carbon source and stirring; transferring the mixture into a hydrothermal reaction kettle for heat preservation; drying the mixture in an oven at 70 DEG C, and grinding the mixture into powder to obtain a precursor; and carrying out heat preservation on the precursor for a certain time under gas protection, then heating to high temperature treatment, carrying out heat preservation for a certain time, and naturally cooling to room temperature to obtain the nano composite material. The sodium-ion battery negative electrode material prepared by the method is high in reversible capacity and good in rate cycle performance.

The invention discloses a porous hard-carbon lithium ion battery anode material, a preparation method thereof and a lithium ion battery. The method comprises steps as follows: hydrogenated vegetable oil powder is prepared firstly and then is subjected to low-temperature carbonizing treatment in inert gas, a precursor is prepared, the precursor is subjected to organic carbon source coating treatment with a solvent and an organic carbon source, material particles are prepared, finally, the material particles are subjected to high-temperature carbonizing treatment, and the porous hard-carbon lithium ion battery anode material is prepared. The method adopts a simple process, a synthesis path is simple and controllable, micro-control for morphology and size of the material is easy, and the prepared porous hard-carbon lithium ion battery anode material is high in reversible capacity and good in rate capability cycle performance and low-temperature performance.

The invention discloses a binding agent and a lithium ion battery. The binding agent is copolymerization-modified PVDF, a structure unit shown in a formula III is included in a main chain of the binding agent, acid/ester functional groups are included on molecular chains and can easily interact with oxidation functional groups on the surface of aluminum foil to form the hydrogen-bond interaction, the flexibility and binding force of the binding agent are improved, and the influences on manufacturing and performance of batteries are relieved.

The invention discloses an additive and an electrolyte and a lithium ion battery using the additive, the additive comprises a compound 1, a compound 2 or a compound 3, the additive can orderly form a film when the battery is charged and discharged for the first time, and a formed solid electrolyte interface film has the characteristics of strong conductivity, strong ionic conductivity and low electron conductivity; therefore, the rate cycle performance, the rate discharge performance and the storage performance of the lithium ion battery can be effectively improved.

The invention relates to the field of lithium ion batteries, in particular to a lithium ion supercapacitor with a positive electrode pre-embedded with lithium. Lithium iron phosphate with an orthorhombic system olivine-type structure is one of positive electrode materials of lithium ion batteries and capacitors which are most widely applied in the current market, and the application of the lithium iron phosphate is greatly limited due to the problems of low electronic conductivity and poor ion diffusion rate. Based on the problem, the invention provides a lithium ion supercapacitor with a positive electrode pre-embedded with lithium, wherein the positive electrode material is a composite material obtained by compounding a spherical lithium iron phosphate material and heteroatom-doped graphene, and the outer side of the composite material is wrapped by a network carbon structure formed by carbonizing melamino-formaldehyde resin, so that the cycling stability and the rate capability of the lithium ion battery are effectively improved, and a relatively good application prospect is achieved.

The invention discloses a high-rate electrolyte of a lithium iron phosphate power battery and a preparation method thereof and the battery. The battery comprises lithium salt and an organic solvent, wherein the organic solvent comprises 90 wt%-95 wt% of a non-aqueous organic solvent and 5 wt%-10 wt% of a functional additive, the non-aqueous organic solvent comprises ethylene carbonate, dimethyl carbonate and ethyl methyl carbonate, the functional additive comprises vinylene carbonate, 1, 3-propane sultone, fluoroethylene carbonate and acetonitrile, and the electrolyte is suitable for the powerbattery with the multiplying power not lower than 6C lithium iron phosphate. According to the battery provided by the invention, the capacity of the battery is kept at 95.6% after 900 times of 3C charge-discharge cycles, the capacity of the battery is kept at 87% after 1000 times of 6C cycles, and the rate cycle performance of the battery is greatly improved.

The invention belongs to the technical field of batteries, and particularly discloses a preparation method of a nano-micron lithium manganese phosphate/carbon composite positive electrode material. The method comprises the steps of carrying out the thermal treatment on a raw material solution containing a manganese source, a lithium source, a phosphorus source, the hexamethylenetetramine and the ethylene glycol at 70-80 DEG C in advance, then carrying out the thermal treatment on the solvent at 160-200 DEG C, mixing the prepared nano-micron lithium manganese phosphate with a macromolecule carbon source, drying and calcining at 500-650 DEG C in a protective atmosphere. The primary particles of the prepared material are nano-scale, grow preferentially and are distributed uniformly, so that the diffusion of the lithium ions in the material is facilitated. The secondary particles are micron-scale, so that the structure stability is facilitated, and the prepared material has the relativelyhigher charge-discharge capacity, excellent cycling stability and good rate capability.