39results about How to "Alleviate chalking problems" patented technology

The invention discloses a graphene-coated copper oxide composite cathode material and a method for manufacturing the same. The graphene-coated copper oxide composite cathode material comprises, by mass, from 20% to 90% of copper oxide and from 10% to 80% of graphene. The method includes uniformly mixing copper salt solution and graphene oxide solution at first, and stirring the copper salt solution and the graphene oxide solution at a constant temperature for 15 minutes to 1 hour to obtain mixed solution; dripping sodium hydroxide solution into the mixed solution, continuously stirring the mixed solution added with the sodium hydroxide solution for 0.5 hour to 2 hours and allowing the mixed solution added with the sodium hydroxide solution to stand for 2 to 24 hours; and performing centrifuging and hydrothermal processing for the mixed solution added with the sodium hydroxide solution to obtain a product, and drying the product at the temperature of 120 DEG C for 12 hours to obtain the graphene-coated copper oxide composite cathode material. The graphene-coated copper oxide composite cathode material and the method have the advantages that the synthesis method is simple, the manufactured graphene-coated copper oxide composite cathode material is good in performance, and technical problems of poor conductivity of a copper oxide electrode and decrease of capacity due to gradual chalking in charge and discharge processes are solved.

The invention discloses a preparation method of nanorod-shaped vanadium tetrasulfide powder, which comprises the following steps: (1) dissolving thioacetamide into absolute ethanol and stirring until completely dissolved to obtain mixture A; (2) dissolving vanadium tetrasulfide Add ammonium acid to mixture A, stir until completely dissolved to obtain mixture B; (3) drop dilute hydrochloric acid into mixture B under stirring conditions to form a transparent solution to obtain mixture C; (4) transfer mixture C to hydrothermal In the reaction kettle, conduct hydrothermal reaction for 24-25 hours; (5) naturally cool after the reaction, centrifuge and wash several times, and vacuum-dry to obtain nanorod-shaped vanadium tetrasulfide powder. The nanorod vanadium tetrasulfide prepared by the invention has high specific capacity, excellent cycle stability, long service life and high conductivity.

The invention provides a conductive binder material, a preparation method thereof, a negative pole piece and a lithium ion battery, and relates to the field of batteries. The conductive adhesive material, including polyvinyl alcohol, sodium carboxymethyl cellulose, sodium alginate, chitosan, polyethyleneimine and other polymers rich in hydroxyl, carboxyl and amino groups, is prepared by high temperature and high pressure or microwave treatment. Aqueous solution of polymer carbon dots. Utilizing the conductive binder material can solve the problem of poor electrical conductivity of the silicon-based material and easy fall off from the pole piece when the silicon-based material is used as the negative electrode active material in the prior art, so as to improve the conductivity of the pole piece and the bonding force of the pole piece material , so as to improve the energy density of the silicon negative pole piece.

The invention discloses a niobium pentoxide / carbon double quantum dot nanocomposite material, a preparation method and an application thereof. The composite material is composed of niobium pentoxide and carbon double quantum dots, and the niobium pentoxide quantum dots and carbon quantum dots are closely combined; the mass fraction of the carbon quantum dots in the composite material is 20-40% . There are gaps between the niobium pentoxide / carbon double quantum dot particles, and the specific surface area is relatively large. This structure is not only conducive to the full contact between the electrolyte and the active material, but also effectively adapts to the volume expansion of the material during charge and discharge, thereby greatly improving its electrochemical performance when used as a negative electrode material for lithium-ion batteries. In the invention, the precursors of niobium and carbon quantum dots are firstly synthesized by a hydrothermal method, and then calcined in an argon atmosphere to obtain a nanocomposite material of niobium pentoxide / carbon double quantum dots. The preparation method is easy to operate, the reaction conditions are controllable, and it is easy to scale up experiments.

The present disclosure discloses a porous structure Si / Cu composite electrode of a lithium ion battery and a preparation method thereof. The composite electrode comprises an active substance, a bulk porous Cu and a current collector, wherein the active substance Si is embedded into the bulk porous Cu, and the bulk porous Cu is in metallurgical bonding with the current collector and plays a dual role of “binder” and “conductive agent”, which not only relieves the pulverization and the shedding of the active substance Si particles but also improves electron transmission efficiency; and meanwhile, the porous structure increases the contact area between the active substance Si and electrolyte and increases the reaction efficiency of lithium insertion combination. The method of preparing the composite electrode comprises: with Si, Cu and Al powders as raw materials, preparing a Si—Cu—Al precursor alloy on the Cu current collector by powder metallurgy and diffusion welding technology; and removing Al element in the Si—Cu—Al precursor alloy by using a chemical de-alloying method to obtain a Si / Cu composite electrode with a porous-structure.

The application discloses a silicon-based composite material which comprises a silicon-based material, wherein the surface of the silicon-based material is modified by an organosilicon compound containing amino and / or carboxyl. The silicon-based composite material is applied to a lithium ion secondary battery, during a battery cycle process, the pulverization of an electrode membrane can be effectively relieved, and battery stability can be improved. When the silicon-based composite material is used with a carboxylic acid binding agent, a polycarboxylate binding agent or a polyimide binding agent in a matching way, hydrogen bonds can be formed by the silicon-based composite material and a polymer in the bonding agent, the adhesion force is enhanced, the incapability of the silicon-based material in contact with the binding agent and a conductive agent due to volume expansion / contraction during the battery cycle process is prevented, and therefore, energy density and cycle performance of the lithium ion secondary battery are effectively improved.

A CNFs loaded MoS 2 Novel magnesium-lithium double-salt battery cathode material and its construction method, CNFs account for x=20-40wt%, MoS 2 Flower-like nanomaterials account for 60-80wt%, and the construction methods include carbon fiber pretreatment, solution preparation, surfactant addition, pH value adjustment, hydrothermal synthesis and product collection, and the final product is one-step hydrothermal synthesis of CNTs in situ loaded MoS 2 Nanocomposite CNFs@MoS 2 , the invention improves the capacity and rate characteristics of the double-salt battery, thereby improving the cycle stability of the magnesium-lithium double-salt battery and improving the battery life.

The invention discloses a lithium-ion battery germanium / carbon composite negative electrode material and a preparation method and an application thereof. The composite negative electrode material includes germanium nanoparticles, mesocarbon microbeads and amorphous carbon. The preparation method comprises the steps of (1) dissolving GeO2 in an alkaline solution, adding nanocrystalline cellulose, adjusting the pH-value of the obtained first suspension, adding the mesocarbon microbeads and stirring to form a second suspension, and transferring the second suspension to a water bath; (2) preparingan NaBH4 solution, adding the heated second suspension, stirring for reaction in the water bath, washing wafer vacuum filtration, then carrying out vacuum drying, roasting the dried solid in an inertgas or reducing atmosphere to obtain the product. The composite negative electrode material disclosed by the invention has high mass capacity and volume specific capacity, can effectively alleviate the volume change and pulverization of germanium, is high in cycle stability and good in compatibility with a propylene carbonate containing electrolyte, has the advantages of good low-temperature electrochemical performance and the like and can be applied to lithium-ion batteries.

The invention relates to a multi-sphere stack-structured Si / TiO2 composite material and a preparation method therefor. The Si / TiO2 composite material comprises Si spheres, and a plurality of TiO2 spheres densely stacked around the Si spheres; and the grain diameter of the Si spheres is larger than that of the TiO2 spheres. In the multi-sphere stack-structured Si / TiO2 composite negative electrode material, silicon active granules are protected by a titanium dioxide nano-particles dense stacked layer; the internal stress generated from volume expansion is fully relieved by taking advantage of the dense stacking characteristic of the Si / TiO2 composite negative electrode material, so that the electrochemical performance and the stacking density of the silicon negative electrode material can be improved, the circulation reversibility of the electrode and the utilization rate of active materials are effectively improved, and the cycle life of the battery is prolonged.

The invention relates to a red phosphorus / nitrogen-doped graphene composite negative electrode material and its preparation method and application. Firstly, nitrogen-doped graphene and red phosphorus are mixed uniformly according to the mass ratio of (2-4):(8-6) , to obtain a mixture; under a protective atmosphere, the obtained mixture is ball-milled to obtain a red phosphorus / nitrogen-doped graphene composite negative electrode material. The present invention utilizes the nitrogen-doped graphene material with good electronic conductivity as the base material, and through ball milling with red phosphorus, the insulating red phosphorus particles can be well dispersed in the conductive nitrogen-doped graphene material during the ball milling process , the complex has a large specific surface area, improves the overall electrical conductivity and increases the contact area with the electrolyte, alleviates the collapse and pulverization of the structure caused by the volume expansion of phosphorus-based materials during the deintercalation of potassium ions, and increases the Potassium ion diffusion rate; as a negative electrode material for potassium ion batteries, it has high reversible capacity, excellent rate performance and cycle stability.