Abstract: Main technical features of an iron core structure of motor rotor provided by the invention are that on a rotor iron core of a rotating motor, along a circumferential direction of a rotation axis of the motor as a center of circle, a plurality of through-hole-shaped spaces spaced apart from each other are arranged on the iron core in sequence. When the through-hole-shaped spaces form obstacles to a magnetic circuit in the rotor, the through-hole-shaped spaces are also provided for insertion of a plurality of straight rod-shaped coupling elements made of non-permeability magnetic material to fix an overlapping state of a plurality of silicon steel plates of the iron core in order to improve an overall rigidity of the iron core and reduce a possibility of deformation or damage of the silicon steel plates caused by centrifugal force of high-speed rotation.

Abstract: A composite electrode and a preparation method thereof are disclosed. The composite electrode includes a composite positive electrode material layer coated on a carrying surface of an electrode plate. The composite positive electrode material layer includes plural positive electrode material particles, a first conductive carbon and a Li-Nafion polymer material. The positive electrode material particles are composed of ternary materials. The first conductive carbon is pre-coated on surfaces of the positive electrode material particles by dry mechanical mixing. A weight percent of the first conductive carbon relative to the positive electrode material particles is ranged from 1 wt. % to 5.5 wt. %. The Li-Nafion polymer material covers the surfaces of the positive electrode material particles and is bonded among the surfaces of the positive electrode material particles. A weight percent of the Li-Nafion polymer material relative to the positive electrode material particles is ranged from 10 wt. % to 20 wt. %.

Abstract: A preparation method of a lithium iron phosphate cathode material includes steps of (a) providing a phosphoric acid, an iron powder, a carbon source, wherein the phosphoric acid and the iron powder are reacted to produce a first product, and the first product is amorphous iron phosphate with chemical formula of a-FePO4·xH2O (x>0); (b) providing a lithium salt mixture, wherein the lithium salt mixture includes a lithium hydroxide and a lithium carbonate; (c) grinding and mixing the first product, the carbon source, and the lithium salt mixture; (d) calcining the first product and the lithium salt mixture to produce a precursor, wherein the precursor has a formula of Fe3(PO4)2·8H2O+Li3PO4; and (e) calcining the precursor and the carbon source to obtain the lithium iron phosphate cathode material.

Abstract: Main technical features of an iron core structure of motor rotor provided by the invention are that on a rotor iron core of a rotating motor, along a circumferential direction of a rotation axis of the motor as a center of circle, a plurality of through-hole-shaped spaces spaced apart from each other are arranged on the iron core in sequence. When the through-hole-shaped spaces form obstacles to a magnetic circuit in the rotor, the through-hole-shaped spaces are also provided for insertion of a plurality of straight rod-shaped coupling elements made of non-permeability magnetic material to fix an overlapping state of a plurality of silicon steel plates of the iron core in order to improve an overall rigidity of the iron core and reduce a possibility of deformation or damage of the silicon steel plates caused by centrifugal force of high-speed rotation.

Abstract: A preparation method of a cathode material for a secondary battery is provided. First, a lithium metal phosphate material and a first conductive carbon are provided. The lithium metal phosphate material is made of a plurality of secondary particles. Each of the secondary particles is formed by the aggregation of a plurality of primary particles. An interparticle space is formed between the plurality of primary particles. Next, the lithium metal phosphate material and the first conductive carbon are mixed by a mechanical method, and a composite material is prepared. The first conductive carbon is uniformly arranged in the interparticle space. After that, a second conductive carbon, a binder and a solvent are provided. Finally, the composite material, the second conductive carbon, the binder and the solvent are mixed, and a cathode material for preparing a positive plate is prepared.

Abstract: A carbon-coated cathode material and a preparation method thereof. The carbon-coated cathode material includes a lithium metal phosphate particle and a carbon coating layer. The carbon coating layer is coated on the lithium metal phosphate particle. The carbon coating layer is formed by a first heat treatment and a second heat treatment. A first carbon source is added in the first heat treatment, and a second carbon source is added in the second heat treatment. The first carbon source has a first weight percentage relative to the lithium metal phosphate particle. The second carbon source has a second weight percentage relative to the lithium metal phosphate particle. The first weight percentage of the first carbon source is equal to or less than the second weight percentage of the second carbon source.

Abstract: A preparation method of a cathode material for a secondary battery is provided. First, a lithium metal phosphate material and a first conductive carbon are provided. The lithium metal phosphate material is made of a plurality of secondary particles. Each of the secondary particles is formed by the aggregation of a plurality of primary particles. An interparticle space is formed between the plurality of primary particles. Next, the lithium metal phosphate material and the first conductive carbon are mixed by a mechanical method, and a composite material is prepared. The first conductive carbon is uniformly arranged in the interparticle space. After that, a second conductive carbon, a binder and a solvent are provided. Finally, the composite material, the second conductive carbon, the binder and the solvent are mixed, and a cathode material for preparing a positive plate is prepared.

Abstract: A cathode material with oxygen vacancy is provided. The cathode material includes a lithium metal phosphate compound having a general formula LiMPO4-Z, wherein M represents at least one of a first-row transition metal, and 0.001?z?0.05.

Abstract: A cathode material with oxygen vacancy is provided. The cathode material includes a lithium metal phosphate compound having a general formula LiMPO4?z, wherein M represents at least one of a first-row transition metal, and 0.001?z?0.05.

Abstract: A cathode material with oxygen vacancy is provided. The cathode material includes a lithium metal phosphate compound having a general formula LiMPO4-Z, wherein M represents at least one of a first-row transition metal, and 0.001?z?0.05.

Abstract: A cathode material with oxygen vacancy is provided. The cathode material includes a lithium metal phosphate compound having a general formula LiMPO4-z, wherein M represents at least one of a first-row transition metal, and 0.001?z?0.05.

Abstract: A cathode material with double carbon coatings is provided. The cathode material includes a lithium metal phosphate matrix, a first carbon coating, and a second carbon coating. The first carbon coating is coated on the lithium metal phosphate matrix. The second carbon coating is coated on the first carbon coating. The carbon source of the first carbon coating is a carbohydrate or a water-soluble macromolecule compound having relatively smaller molecular weight. The carbon source of the second carbon coating is a macromolecule compound having relatively higher molecular weight.