30results about How to "Reduce compacted density" patented technology

The invention discloses a preparation method of high-compression high-capacity lithium iron phosphate. Weigh iron phosphate, lithium carbonate, polyethylene glycol and sucrose, then mix them, add alcohol for wet grinding; spray dry the slurry, and crush the spray-dried materials to obtain crushed materials; put the crushed materials into the roller The sintering is carried out in the first furnace, and the sintering is divided into four stages, namely, the heating section, the heat preservation section, the decarburization section and the cooling section. After crushing, screening, and iron removal in the wet room, vacuum packaging is carried out to obtain high-compression and high-capacity lithium iron phosphate. The method of the invention is simple and low in cost, and at the same time, the lithium iron phosphate with high compacted density and good electrical performance can be obtained through gas treatment of carbon dioxide.

The invention discloses a preparation method of a lithium-ion battery that improves high-voltage low-temperature discharge and cycle performance, and belongs to the technical field of lithium-ion batteries. The preparation method is as follows: a layer of negative electrode slurry A with a thickness of 170um~240um is coated on the paste surface of the negative electrode current collector, and the negative electrode slurry A is composed of negative electrode main material, high specific surface area conductive agent, CMC , SBR, and modified acrylic binder; a layer of negative electrode slurry B with a thickness of 170um~240um is coated on the short pasted surface of the negative electrode current collector, and the negative electrode slurry B is composed of negative electrode main material, low specific surface area Composed of conductive agent, CMC and SBR; rolling → sorting. The present invention uses two coating processes to coat different types of slurries on both sides of the negative electrode current collector to improve the bonding performance of the negative electrode active material and the current collector and the liquid absorption performance of the negative electrode sheet, especially improving the long-term coating The polarization effect between the paste surface and the negative electrode current collector improves the low-temperature discharge and cycle performance of the high-voltage battery.

The invention discloses a preparation method of a silicon-carbon anode material and a lithium ion battery. The preparation method includes: mixing nano-silicon with graphite solid phase, sieving the mixture, mixing the mixture with an amorphous carbon precursor solid phase, sieving the mixture, performing vibrating shaping, and sintering the product to obtain the silicon-carbon anode material. Bymeans of sieving, the graphite, nano-silicon and amorphous carbon precursor are dispersed, so that the surface of graphite can be uniformly coated with the nano-silicon and the surface of nano-siliconcan be uniformly coated with the amorphous carbon precursor; through the vibrating shaping, surface-to-surface contact between the amorphous carbon precursor and the nano-silicon and between the nano-silicon and the graphite is achieved without existence of a gap; through the sintering step, a volatile substance can be slowly volatilized from interior to exterior, so that a problem of forming pores since a huge gas pressure is generated from the volatile substance can be avoided. The silicon-carbon anode material, when being used for producing the lithium ion battery, shows excellent electrochemical cyclic stability.

The invention provides a preparation method of a lithium ion battery positive electrode with high rate performance, the positive electrode comprising a current collector and a first active material layer, a second active material layer and a passivation conductive layer which are located on the current collector, the first active material layer comprising lithium nickel oxide, the second active material layer comprising doped lithium manganese cobalt oxide and doped lithium iron phosphate, the passivation conductive layer comprising inorganic oxide particles and an organic conductive polymer.The preparation method of the invention obtains a positive electrode with high conductivity, stable structure and good cycling performance in a high-rate environment by controlling the production process.

The invention provides a method for preparing a lithium ion battery mixed positive electrode. Slurries comprise different proportions of a first active material, a second active material and a third active material, wherein the molecular formula of the first active material is LiNi0.8Mn0.1Co0.1O2, the molecular formula of the second active material is LiNi0.3Mn0.4Co0.3O2, and the molecular formulaof the third active material is LiMnPO4, and particles with two particle sizes exist in the first active material; the average particle size of the second active material is 50-200 nm, the length-to-diameter ratio of the second active material is 1.1-1.3, and the D90 / D10 value of the second active material is 1.6-2.2; and the average particle size of the third active material is 0.5-1 [mu]m, thelength-to-diameter ratio of the third active material is 1.5-2, and the D90 / D10 value of the third active material is 1.2-1.5. The slurries are respectively prepared according to the different structures of the active materials, a current collector is respectively coated with the slurries to sequentially obtain a first active material layer, a first active material and second active material mixedlayer and a third active material layer along a direction from a position adjacent to the current collector to a position away from the current collector. The slurries obtained in the invention havegood dispersibility and good retention performances, and the positive electrode has good high-rate performances and a high energy density.