6results about How to "Considerable reversible capacity" patented technology

The invention discloses a preparation method of a phosphorus-doped hard carbon composite material for a sodium battery. The preparation method comprises the following steps: preparing a hard carbon precursor, preparing a phosphorus-doped precursor, preparing a catalyst precursor, preparing a hard carbon composite material, and carrying out pickling purification. Through pre-oxidation treatment on the biomass raw material, oxygen-containing free radicals can be introduced, the structural disorder can be improved, the sodium storage space and the capacity can be improved, phosphorus elements are uniformly distributed into the hard carbon material through a vapor deposition method, meanwhile, graphene and carbon nanotubes are formed in the material, closed pores are increased, the sodium storage space is improved, and the performance of the hard carbon material is improved. According to the present invention, the ion transmission path is shortened, the sodium ion transmission is accelerated, the capacity and the conductivity of the material are enhanced, the material is coated with the amorphous carbon formed by the asphalt, such that the phosphorus expansion can be inhibited, the contact with the electrolyte can be avoided, the capacity and the first effect can be improved, and the phosphorus and the coating layer can be re-distributed while the asphalt coating is performed so as to form the small amount of the phosphorus fiber crystal; and the conductivity and the capacity are improved.

The invention belongs to the technical field of sodium ion batteries, and discloses a preparation method of an ion-doped low-nickel layered oxide sodium ion battery positive electrode material. The chemical formula of the sodium ion battery positive electrode material is Na < 0.95-x > Ca < x > (Ni < 0.2 > Fe < 0.4 > Mn < 0.4 >) < 1-y-z > Li < y > Mg < z > O < 2 >. The preparation method comprises the following steps: weighing a sodium source, a nickel-iron-manganese hydroxide, a calcium source, a lithium source, a magnesium source and a certain amount of a dispersing agent in a ball-milling tank, and carrying out ball-milling mixing to obtain a sodium-ion battery positive electrode material precursor; and placing the sodium ion battery positive electrode material precursor in a corundum crucible, transferring the corundum crucible to a box-type atmosphere furnace for segmented sintering, naturally cooling to room temperature after sintering is completed, and grinding and sieving to obtain the ion-doped low-nickel layered oxide sodium ion battery positive electrode material. The positive electrode material has the advantages of low cost, low strain, high capacity, good cycle stability, simple preparation process, high repeatability and great potential of large-scale production.

The invention provides a negative electrode material and a preparation method and application thereof. The negative electrode material comprises a carrier and a coating layer at least partially covering the surface of the carrier, the coating layer contains a soft carbon material and a hard carbon material, the content of the soft carbon material is gradually reduced from inside to outside, and the content of the hard carbon material is gradually increased from inside to outside. The structure has good reversible capacity, rate and cycle performance, and the cycle performance, rate performance and safety performance of the material are improved. The invention also provides a preparation method and application of the negative electrode material.

The invention discloses a carbon-coated tin nanoparticle, a preparation method thereof and a lithium ion battery material thereof, and relates to the field of battery materials, the preparation method comprises the following steps: dissolving bacillus subtilis spores in deionized water, and adding glucose for activation culture to obtain supernate; adding SnCl4, and incubating to obtain a suspension liquid; adding a complexing agent, carrying out ultrasonic treatment, and centrifuging to remove a complex, so as to obtain centrifugate; centrifugally collecting precipitates; dissolving the precipitate in deionized water, and carrying out ultrasonic oscillation to obtain a solution; the method comprises the following steps: dissolving a carbon nanotube or graphene oxide in a solvent to obtain a carbon nanotube solution or a graphene oxide solution; mixing the solution with the carbon nanotube solution to obtain a mixed solution; freezing and drying; and placing the powder in a protective gas atmosphere for high-temperature annealing to obtain the product. The method has the beneficial effects that voids in the bacterial carbon shell relieve volume expansion of tin particles in lithiation and lithium removal processes, and the carbon nanotubes uniformly integrated in the bacterial carbon shell serve as efficient electron conduction channels to disperse anisotropic stress.

The application relates to a one-step method for preparing metal sulfide ultrathin nanosheets and application, which comprises the following steps: step one: uniformly mixing a metal salt, a salt template agent and thiourea in ethanol to obtain a precursor mixed liquid; step two: performing heating and drying on the precursor mixed liquid to obtain a precursor powder; step three: performing heat treatment on the dried precursor powder; and step four: soaking the heat-treated precursor powder in deionized water, and then performing cleaning and drying to obtain a metal powder, namely the metal sulfide ultrathin nanosheet. The method for preparing the metal sulfide ultrathin nanosheet provided by the application does not need to additionally introduce a sulfur source, is simple and easy to operate, has low cost, and the obtained metal sulfide two-dimensional ultrathin nanosheet has uniform morphology, can provide a larger specific surface area, abundant energy storage sites and a shorter diffusion distance, and has great application prospects in the field of alkali metal ion batteries-potassium ion batteries.

This invention discloses a lithium-rich manganese-based layered oxide composite cathode material and its preparation method, belonging to the field of lithium-ion battery technology. The method includes: adding water to a nickel source, a cobalt source, and a manganese source to obtain a mixed solution; adding sodium carbonate solution to adjust the pH; washing with deionized water and centrifuging; drying; mixing with lithium salt; and pre-calcining to obtain Li. 1.2 Ni 0.13 Co 0.13 Mn 0.54 O 1.8 F 0.2 The material was then subjected to a process involving the sequential addition of a carbon source and an organic solvent. The resulting mixture was heated under a mixed atmosphere to obtain a lithium-rich manganese-based basal oxide material. Na₂WO₄ and pyrrole were then added, and the mixture was dissolved in deionized water to obtain a composite cathode material, Li. 1.2 Ni 0.13 Co 0.13 Mn 0.54 O 1.8 F 0.2 @N,S-C@Na2WO4@PPy. The composite cathode material of this invention has uniform particles, stable structure, and exhibits considerable wide potential window reversible capacity, excellent rate performance, and stable cycle life.