31results about How to "Improve high current charge and discharge capability" patented technology

The invention discloses a silicon-carbon negative electrode and a preparation method thereof. The silicon-carbon negative electrode comprises a current collector, an active material layer coated on the current collector, and a functional coating coated on the active material layer; the functional coating includes a poly Pyrrole and single-wall carbon nanotubes, polypyrrole and single-wall carbon nanotubes form a three-dimensional mesh conductive network. The present invention also provides a method for preparing a silicon carbon negative electrode, comprising: (1) coating an active material layer slurry on a current collector; (2) coating a functional coating slurry on an active material layer of a current collector to obtain a silicon carbon negative electrode. The carbon negative electrode; the functional coating slurry is prepared by the following method: the pyrrole monomer is dispersed in a solution containing single-walled carbon nanotubes to prepare the functional coating slurry; during the reaction, the pyrrole monomer is polymerized to form polypyrrole, Polypyrrole and single-walled carbon nanotubes form a three-dimensional mesh-like conductive network. The silicon-carbon negative electrode of the invention suppresses the volume expansion of the silicon-carbon negative electrode of the silicon-based lithium ion battery, and improves the conductivity of the silicon-carbon negative electrode.

The invention discloses a preparation method of porous nanoscale TiNb2O7. The preparation method of the porous nanoscale TiNb2O7 comprises the following specific steps: (a) adding a titanium source and a niobium source in the molar ratio of 1 to 2 into a dispersant, dispersing and mixing; and (b) pouring the mixture obtained in the step (a) into a porcelain boat, roasting at the temperature of 700-900 DEG C, preserving heat for 3-6 hours, and cooling the product of reaction to room temperature to obtain the porous nanoscale TiNb2O7, wherein the temperature is increased at a speed of 1-5 DEG C per minute. The preparation method of the porous nanoscale TiNb2O7 is easy to operate, and the obtained porous nanoscale TiNb2O7 has small particle size, uniform particle size distribution and good stability and consistency. Due to the abundant pore passages of the porous nanoscale TiNb2O7, an active material can be fully soaked by an electrolyte, and due to the nanoscale particles of the porous nanoscale TiNb2O7, the transmission distance between lithium ions and electrons in the charging and discharging process can be shortened effectively, and the high-current charging and discharging capability of the TiNb2O7 can be improved. The porous nanoscale TiNb2O7 has excellent electrochemical properties and broad application prospects.

The invention discloses a preparation method of a carbon-coated ternary cathode material, belonging to the technical field of lithium ion batteries. 11) adding the ternary cathode material and the silicon dioxide precursor into an organic solvent, uniformly mixing, dripping deionized water, stirring for reaction, evaporating all solvent, and calcining to obtain the silicon dioxide-coated ternary cathode material; (2) adding silica coated ternary cathode material and organic carbon source into dispersant to obtain suspension, evaporating and sintering to obtain silica coated ternary cathode material and carbon coated ternary cathode material; (3) immersing the ternary cathode material coated with silicon dioxide and carbon in alkaline solution to obtain the ternary cathode material coated with carbon. A silicon dioxide layer is used as an intermediate protective layer to prevent a carbon source from releasing a reducing gas to reduce a main material in a high-temperature carbonization process, so that a carbon coating formed by the silicon dioxide layer can give full play to its conductivity, thus improving the charging and discharging capacity of a battery at a large current, and further improving the rate performance.

The producing method applies the normal temperature reactive solution SnCl2 as the solution, the ammonia as the precipitator, and the cabamide as the compound to supply the O-H, and the KBH4, NaH2PO2 as reducer. The catalyst and some compound complexing agent are also added. During the reaction procedure, the concentration of the reducer is to be controlled to keep definite ratio Sn, to reduce the irreversible capacity in the electrochemical lithium storage procedure. The material produced effectively remites the volume changing of the electrode resulted in the discharging process.

The invention provides a Pb / C supercapacitor battery cathode preparation method, and aims to provide a supercapacitor battery cathode preparation method which is high in active material utilization rate, good in power characteristic, small in leakage current, long in cycle life and excellent in pole piece electric energy storage and release performance. The method is implemented through the following technical scheme which comprises the steps of firstly adding 5%-15% of modified functionalized activated carbon material slurry with high specific surface area into a stirring tank, and stirring for 10-15min; then adding 50wt%-65wt% of cathode active material lead powder with the oxidation degree being 75%, 1wt%-5wt% of conductive agent and 1wt%-3wt% of addition agent into the stirring tank, and stirring for 5-10min; then adding 10wt% of deionized water, and stirring for 25-30min; and finally adding 10wt% of H2SO4 with the concentration being 6mol / L, and stirring for 20min so as to prepare energy storage type or a power type supercapacitor battery cathode material paste. The modified functionalized activated carbon material slurry with the high specific surface area is cleaned by HNO3, H3PO4 and a urea solution with the temperature being 90-100DEG C and loaded with part of metal compounds.

The invention relates to a sodium ion capacitor with a negative pole made of a FeS2-xSex material. The sodium ion capacitor comprises a positive pole sheet, a negative pole sheet, a diaphragm, an electrolyte and a shell; an active material, a conductive agent and a binder are mixed, a solvent is added into an obtained mixture, the solvent and the mixture are mixed to form a slurry, the slurry coats a collector, and therefore, the negative pole sheet can be obtained; and the active material in the negative pole sheet of the capacitor is the FeS2-xSex material, wherein x ranges from 0.1 to 1. The negative pole of the sodium ion capacitor of the invention is made of the FeS2-xSex material; the peak position of the XRD diffraction pattern of the FeS2-xSex material slightly shifts leftwards compared with that of FeS2, which indicates that an inter-layer spacing is increased, and therefore, the implanting and extraction of sodium ions can be better facilitated; the diffusion of Na<+> is faster, electronic conductivity is higher, and therefore, the high-current charge and discharge capacity of the sodium ion capacitor can be greatly improved, namely, the power performance of the sodium ion capacitor is improved; if the power density of the sodium ion capacitor is 172 W kg<-1>, the energy density of the sodium ion capacitor is as high as 67 Wh kg<-1>; and even if the power density of the sodium ion capacitor is as high as 2543 W kg<-1>, the energy density of the sodium ion capacitor is still maintained at about 27Wh kg<-1>.