30results about How to "Won't lose powder" patented technology

The invention discloses a preparation method for a hydrophilic silicon dioxide aerogel microsphere. Specifically, the preparation method comprises the following steps: 1) adding tetralkoxysilane and hydroxyl-contained hydrophilic compound into a solvent to be evenly dispersed, and adding acid to obtain prepolymer; 2) dispersing in an aqueous phase to carry out self-assembling; 3) adding alkali for washing; 4) drying. The preparation method has the advantages of environment protection, simpleness in operation and low cost. The hydrophilic silicon dioxide aerogel microsphere obtained with the method is provided with a silicon dioxide shell with smaller holes and a silicon dioxide skeleton with a larger-hole structure, wherein the silicon dioxide skeleton is covered in the silicon dioxide shell. The invention also discloses the hydrophilic silicon dioxide aerogel microsphere which has relatively good dispersion performance, and has high adhesive force with a matrix when being applied to a coating.

The invention provides a non-woven ceramic membrane with excellent closed-pore performance for a lithium ion battery. The non-woven ceramic membrane comprises a non-woven base material and coatings with the closed-pore performance. The non-woven ceramic membrane is characterized in that the coatings with the closed-pore performance are uniformly coated on the two surfaces of the non-woven base material, the thickness of the non-woven ceramic membrane for the lithium ion battery is 30-50mu m, the porosity of the non-woven ceramic membrane is 40-60%, the average pore diameter of the non-woven ceramic membrane is 0.1-0.5mu m, the closed-pore temperature of the non-woven ceramic membrane is 120-130 DEG C, and the membrane rupture temperature of the non-woven ceramic membrane is 300-500 DEG C. The invention also provides a preparation technology of the non-woven ceramic membrane with the excellent closed-pore performance for the lithium ion battery. The non-woven ceramic membrane has the advantage that the disintegration or explosion of the battery is not easy cause; the adhesive power between the ceramic coating and the base material is increased, and no powder falls off the surface of the membrane under the conditions of bending, rubbing and the like; the consistency of the membrane thickness is substantially improved; and the non-woven ceramic membrane has good high temperature resistance performance, high ion penetrability, low resistance and stable electrochemical property.

The invention provides a polyimide thin film for preparing an artificial graphite film with excellent mechanical properties and a preparation method of the polyimide thin film. The polyimide thin film is prepared from a raw material diamine monomer which comprises 0 to 75 mol ratio of p-phenylenediamine; the raw material dianhydride monomer, comprises 40 percent to 100 mol ratio of of pyromellitic dianhydride; two types of inorganic fillers, including a calcium-containing compound and transition metal oxide, are uniformly dispersed in the polyimide thin film. The polyimide thin film provided by the invention is applicable to a graphitization process of single-sheet, multilayered stacking and continuous coiled materials and can be used for carrying out graphitization at temperature of 2300 DEG C; the crystallization degree is less than 10 percent. The graphite film prepared from the polyimide thin film has an excellent heat conducting property and has excellent mechanical properties in longitudinal and lateral directions of the thin film; the modulus is less than or equal to 2000MPa, the elongation at break is more than or equal to 3 percent, the tensile strength is more than or equal to 40MPa and the difference of the longitudinal and lateral directions is less than 15 percent.

The invention discloses a method for preparing a negative electrode sheet of a lithium battery, comprising the following steps: step S1: mixing CMC, negative electrode active material, conductive agent and deionized water to form a solution A; step S2: continuing in the A solution Add SBR and carbon precursor, stir to form a slurry; step S3: apply the slurry on copper foil to form a wet film pole piece; step S4: heat the wet film pole piece to 270-330°C to obtain The negative electrode sheet of the lithium battery. The preparation method of the negative pole piece provided by the present invention reduces the addition of SBR, and by adding a small amount of carbon precursor, the carbon precursor is heated and decomposed to form carbon chains of functional groups such as carbonyl and double bonds, and then in the process of adding electrolyte and charging and discharging, Slow down the cell expansion caused by SBR swelling, and the pole piece itself will not lose powder due to the reduction of SBR addition.

The invention discloses a high temperature-resistant cellulose fiber base material-containing lithium ion battery diaphragm and a preparation method of the same. The battery diaphragm is characterized in that the thickness is 20-40 micrometers, the poriness is 40-60%, the gas permeability is 15-30sec / 100cc; and the diaphragm comprises the cellulose fiber base material, a porous bonding layer and an inorganic coating layer. The preparation method comprises the following steps of: mechanically foaming the waterborne polyurethane emulsion, conveying the foam glue to a foam bath device, dragging and immersing the cellulose fiber base material in the foam bath for gluing, and forming the porous bonding layer on the surface of the base material by the foam glue; spreading an inorganic coating on the surfaces of the cellulose fiber base material and the porous bonding layer to form the inorganic coating layer compositely; and drying. The battery diaphragm provided by the invention has better solution absorption and solution preserving capability to the electrolyte; the battery diaphragm cannot shrink, and the hot-shrinkage rates in longitudinal direction and transverse direction both are less than 2%; and the battery diaphragm is relatively high in ion penetrability, relatively lower in resistance, excellent in mechanical performance and steady in electrochemical performance, and can prevent battery short circuit and dendritic crystal diapirism.