88results about How to "The first discharge specific capacity is high" patented technology

The invention discloses a carbon-silicon composite material, a preparation method of the carbon-silicon composite material and a lithium ion battery containing the carbon-silicon composite material. The preparation method comprises the steps of: directly selecting silicon powder as a raw material, wrapping the silicon powder with a precursor of organic carbon to obtain a porous carbon layer wrapping silicon composite material, and using corrosive liquid to remove partial silicon in the porous carbon layer wrapping silicon composite material by corrosion, so as to obtain the carbon-silicon composite material, wherein a gap exists between a carbon shell and the silicon arranged in the carbon shell. The preparation process is simple. The carbon-silicon composite material prepared by the preparation method disclosed by the invention is good in electrochemical property, and the battery prepared from the carbon-silicon composite material is good in cycling performance.

The invention provides a high-performance water system zinc ion battery anode material, a manufacturing method and an application thereof. The anode material has the following general formula: (N,M) sigma=1V8O20 nH2O, wherein the N is one of Li, Na, K, Zn, Cu, Mg or Ca, the M is one of Mn, Fe, Co or Ni, and the n is 0.01-4. The anode material can be manufactured through one-step hydrothermal method, a reaction condition is mild, a manufacturing process is simple, and a requirement to equipment is low. A microscopic morphology of the obtained anode material is a nanobelt. The obtained anode material is firstly applied to a water system zinc ion battery, and has electrochemical performance such as a higher specific discharge capacity, a higher cycle stability and the like.

The invention discloses a lithium sulfur battery anode material and preparation method thereof, melamine formaldehyde resin rich in nitrogen is taken as a carbon source and nitrogen source, a nitrogen-rich hollow eggshell with the diameter of 100-300 nm is prepared with a nanometer SiO2 casting method, the interfacial adsorption of polysulfide is enhanced by the aid of the combined effect of physical adsorption and chemical adsorption, migration and shuttle effects of the polysulfide are effectively restrained, and charge and discharge stability of a lithium sulfur battery is enhanced. At the same time, an eggshell structure is formed after the hollow eggshell is filled with sulfur, and an interior gap exists between a sulfur inner core and a polymer shell so as to accommodate volume expansion in a sulfur atom lithiation process. The lithium sulfur battery anode material is applied to preparation of a lithium sulfur battery anode and the lithium sulfur battery. The lithium sulfur battery has excellent cycle performance and capacity retention ratio.

The invention provides a three-dimensional nanometer porous copper/two-dimensional cuprous oxide nanosheet array type lithium ion battery negative electrode. The lithium ion battery negative electrode comprises a three-dimensional nanometer porous copper substrate and a cuprous oxide nanosheet array layer, the three-dimensional nanometer porous copper substrate is used as a current collector, the cuprous oxide nanosheet array layer is used as an active lithium storage layer, the cuprous oxide nanosheet array is arranged on a surface of the substrate and is integrated with the substrate, and the cuprous oxide nanosheet array layer comprises cuprous oxide nanosheets formed on the substrate through in-situ growth, and the cuprous oxide nanosheets are perpendicular to the three-dimensional nanometer porous copper substrate and are arranged in a staggered manner to form an array structure. By the lithium ion battery negative electrode, the cycle performance and the specific capacity of the lithium ion battery can be improved. The invention also provides a one-step preparation method of the abovementioned lithium ion battery negative electrode. By the method, the production process of the lithium ion battery negative electrode can be effectively simplified.

The invention relates to a method for preparing lithium iron phosphate; wherein, the method includes mixing the water solutions of a ferric salt, a phosphoric acid and/or a phosphate, and an ammonia and/or an organic amine with the carbon atom number of 1 to 4 to acquire a mixture; drying the spray of the mixture to acquire a solid powder body; roasting the solid powder body with a temperature of 300- 900 DEG C and a time of 2- 24 hours to acquire an iron phosphate powder body; mixing the acquired iron phosphate powder body with a lithium salt and a carbon source uniformly and sintering thereof under an inert gas and/or a reducing gas. The first discharging capacity of a battery made by adopting the lithium iron phosphate prepared by the invention is remarkably higher than that of a battery made by the lithium iron phosphate prepared by the prior art.

The invention relates to a preparation method for a spirogyra-based biomass carbon material/nanometer sulfur composite material. The method comprises the following steps of washing and drying spirogyra, heating the washed and dried spirogyra in a vacuum tubular furnace, carrying out heat preservation and carbonization at 500-900 DEG C, mixing the carbonized spirogyra with nanometer sulfur with ultrasound, carrying out ball milling, drying the ball-milled mixture by an air blow drying box, heating the dried mixture in the vacuum tubular furnace, carrying out heat preservation for 3-6 hours at 100-200 DEG C, and afterwards cooling the mixture subjected to heat preservation to a room temperature with the furnace to obtain the target product, namely the spirogyra-based biomass carbon/nanometer sulfur composite material. According to the preparation method, the spirogyra is taken as a precursor for the first time, and a biomass carbon material with a continuous sheet-shaped structure similar to graphene and with nanoscale thickness is synthesized; the biomass carbon material comprises the sheet-shaped structure composed of continuous fibers, also is provided with nanoscale pores and is high in uniformity and continuity, the loading of sulfur particles is facilitated, and the obtained composite material has favorably electrochemical performance.

The invention discloses a positive electrode active material precursor and a preparation method thereof, and a positive electrode active material. The positive electrode active material precursor comprises secondary particles formed by aggregation of a plurality of primary particles, each secondary particle comprises an internal area and an external area coating the external side of the internal area, the density of the internal area is smaller than that of the external area, and the density of the external area is gradually increased from inside to outside. According to the positive electrodeactive material precursor of the invention, the positive electrode active material adopting the positive electrode active material precursor has high initial charge specific capacity, initial discharge specific capacity, initial coulombic efficiency and cycle performance, so that the lithium ion secondary battery can have high initial charge specific capacity, initial discharge specific capacity,initial coulombic efficiency and cycle performance at the same time.

The invention relates to a method for preparing a composite anode material LiFePO4/C for a lithium ion battery. The method comprises the steps of mixing, reacting, drying, calcining and cooling and is characterized in that: lithium salt, ferric salt and phosphate are mixed with a chemical substance, namely, formaldehyde capable of forming an ideal carbon gel pre-condensed substance and a resorcinol composition so as to form a complex rheological phase reaction system for preparing an LiFePO4/C high molecular polymer; and reaction substances for preparing the LiFePO4 are uniformly distributed in the carbon gel pre-condensed substance. Simultaneously, polyethylene glycol (PEG) is added, pH is controlled and a reaction system is adjusted so as to adjust the structure of the carbon gel pre-condensed substance, a netlike porous structural material which is distributed uniformly can be obtained by calcining and carbon is uniformly coated on the surface of the LiFePO4. Under the condition of10C multiplying power, discharge specific capacity is up to 120.56mAh/g and circulating performance is high. The prepared anode material has a stable structure and high cyclical stability, does not contain any heavy metal and is an environmentally-friendly material.

The invention discloses a method for preparing a lithium ion battery anode material xLiFePO4.yLi3V2(PO4)3, and relates to a method for preparing a lithium ion battery anode material. The method solves the technical problems of poor magnification performance and complex synthesis process in the conventional method for synthesizing the xLiFePO4.yLi3V2(PO4)3. The method comprises the following steps of: weighing lithium source, iron source, vanadium salt, phosphate and carbon source, mixing, and performing wet milling, pre-sintering and calcination to obtain the xLiFePO4.yLi3V2(PO4)3. The process is simple, and environmental pollution easily caused in a liquid phase method is not caused. The anode material prepared by the method has good magnification discharge performance; and during 10C discharge, the discharge specific capacity is 90mAh/g, and the capacity is nearly not attenuated after 20 times of cycles.

The invention discloses a preparation method of a lithium ion battery anode material Li3V2(PO4)3. The preparation method provided by the invention mainly solves the problem that the existing high-temperature solid-phase method and the existing carbon-thermal reduction method for preparation of lithium vanadium phosphate have the defects that a sintering temperature is high; sintering time is long; a volatile organic solvent is utilized as a ball milling dispersant so that a cost is high; spray and drying processes are unsafe; and a sol-gel technology is complex. The preparation method comprises the following steps of weighing one or more lithium sources, V2O5, a carbon source and a phosphorus source, adding the one or more lithium sources, V2O5, the carbon source and the phosphorus source into a hydrogen peroxide aqueous solution, carrying out wet ball milling, and carrying out calcination at a temperature of 550 to 650 DEG C in a protective atmosphere to obtain the lithium ion battery anode material Li3V2(PO4)3. The preparation method provided by the invention has simple processes, a low synthesis temperature, short sintering time and high production safety. The lithium ion battery anode material Li3V2(PO4)3 obtained by the preparation method has an initial discharge specific capacity of 104mAh/g under multiplying power of 10C and a capacity retention ratio great than or equal to 96.4% after 50 cycles. The preparation method provided by the invention is utilized for preparation of battery anode materials.

The invention discloses a method for modifying a ZrO2-coated lithium-rich laminar cathode material of a lithium ion battery. The method comprises the steps as follows: dissolving zirconium isopropoxide, zirconium propoxide or tetrabutyl zirconate in a solvent to prepare 0.001-1 mol/L of zirconate solution; dispersing the lithium-rich laminar cathode material in the prepared zirconate solution according to the mass ratio of ZrO2 to the lithium-rich laminar cathode material, ultrasonically mixing, sealing and stirring to obtain sol; evaporating the solvent of the prepared sol to dryness and drying to obtain a solid matter; and sintering the obtained solid matter for 1-10 h at the temperature of 350-600 DEG C to prepare the ZrO2-coated lithium-rich laminar cathode material. The ZrO2-coated lithium-rich laminar cathode material prepared with the method has the characteristics of high electrochemical capacity, good cycle stability, excellent rate performance and the like; and the preparation method is simple, easy, low in cost and good in reproducibility.

The invention provides a preparation method of spherical lithium iron phosphate, which belongs to the technical field of lithium battery anode materials and solves the problems of low tap density, lowconductivity, irregular shape, unstable performance, poor post-processing affinity, and the like of lithium iron phosphate prepared by the preparation method of the prior lithium iron phosphate. Thepreparation method of spherical lithium iron phosphate comprises the following steps: A, preparing lithium iron phosphate powder; and B, preparing the spherical lithium iron phosphate. The preparationmethod of the spherical lithium iron phosphate has simple technical process and low production cost and is suitable for large-scale production. The prepared spherical lithium iron phosphate has smallgranularity, large tap density and high first discharging specific capacity at room temperature.

The invention relates to a preparation method of a high-capacity lithium ion battery cathode material of lithium nickel cobalt aluminate. The preparation method comprises: adding a nickel-containing compound, a cobalt-containing compound, a lithium-containing compound, and an aluminium-containing compound into a high temperature-resistant ball-milling tank and performing uniform mixing; putting the tank into a mechanical device capable of heating and rotating; performing ball milling at a room temperature; performing mixing for 5-20h; sintering the reactants in the ball-milling tank in the presence of air flow or oxygen flow at two temperature segments while keeping ball milling, wherein firstly, elevating the temperature to 400-600 DEG C in the presence of air flow or oxygen flow and performing sintering for 2-10h, and elevating the temperature to 700-900 DEG C in the presence of air flow or oxygen flow and performing sintering for 5-30h; performing cooling while performing ball milling till the temperature is relatively low; and opening the device to obtain cathode material powder of lithium nickel cobalt aluminate. The method is simple in technology, and raw materials can be completely mixed through high-temperature ball milling to obtain the cathode material of lithium nickel cobalt aluminate. In a voltage range of 3.0-4.2V and under a rate of 0.2C, the cathode material has an initial discharge specific capacity higher than 180mAH/g and has excellent cycle performance.

The invention discloses a spinel phase coated lithium-rich material Li1.87Mn0.94Ni0.19O3, a preparation method and an application therefor, and belongs to the electrochemical technical field. The invention discloses a new material used as a lithium ion battery positive electrode, namely the spinel phase coated lithium-rich material Li1.87Mn0.94Ni0.19O3, and the preparation method is simple. When the material is used as the positive electrode material of a button lithium battery, the cycling stability of the button lithium battery under a high rate of 1C (250 mA/g) can be improved, and a relatively high specific capacity can be ensured as well; at present, the stable cycling performance of the button lithium battery under the rate of 1C is improved to be more than 200 circles; and meanwhile, the capacity is kept at about 180mA/g.

The invention discloses an anode material for lithium ion batteries and a preparation method of the anode material. A sodium salt, a barium salt, a strontium salt, a lithium salt and a titanium salt are mixed in proportion, and the novel material for the lithium ion batteries is prepared through ball-milling, drying, grinding and sintering synthesis; the chemical formula of the anode material is Na0.5Ba0.25Sr0.5Li2Ti6O14, and the electrochemical performance and lithium storage performance of the cathode material are researched. Electrochemical experiments prove that the composite material prepared through the method has excellent physical and chemical properties, and has wide application prospect as the anode material for the lithium ion batteries. In the whole preparation process, the synthetic method is simple and easy to operate, the material preparation cost is low, the equipment investment is low, and the anode material is applicable for volume production.

The invention belongs to the field of lithium sulfide battery positive electrode material and specifically relates to a preparation method and application of a lithium sulfide battery positive electrode. The lithium sulfide battery positive electrode comprise a positive electrode active material, a stabilizer, a conductive agent and a bind, wherein that positive electrode active material is insoluble sulfur. The stabilizer is a compound capable of forming a common electron pair with sulfur atoms at both ends of the positive electrode active material, preferably at least one of a halogen, an organic halide and a thiazole compound. The positive electrode active material of the invention greatly reduces the dissolution of the polysulfide, and the insoluble sulfur stabilizer used together caneffectively restrain the generation of dead sulfur and the shuttle effect in the electrode reaction process. The positive electrode assembled lithium sulfide battery provided by the invention has highfirst discharge specific capacity and good cycle performance. In addition, the preparation method of the sulfide positive electrode provided by the invention is low in cost, simple in operation and easy to realize large-scale commercial manufacture.

The invention discloses carbon-coated Na2Li2Ti6O14 nanofiber and a preparation method thereof. Sodium salt and titanium salt are dissolved in N,N-dimethylformamide; lithium salt is dissolved in a mixed solvent of ethyl alcohol and glacial acetic acid; then, two solutions are mixed; macromolecule polyvinylpyrrolidone is added; stirring is performed so that a clear solution is formed; the clear solution is subjected to electrostatic spinning under certain voltage, certain volume flow rate and certain relative humidity; an electrostatic spinning product is dried at constant temperature; then, high-temperature sintering is performed and corresponding Na2Li2Ti6O14 nanofiber is obtained; then, carbon coating is performed. The preparation of the carbon-coated Na2Li2Ti6O14 nanofiber is successfully realized; when the prepared nanofiber is used as a lithium ion battery negative electrode material to perform performance test representation, a result shows that the nanofiber has excellent physical and chemical properties, and has wide application prospects when being used as the lithium ion battery negative electrode material. In the whole preparation process, the operation is simple; the raw material cost is low; the equipment investment is low; the nanofiber is suitable for batch production.