Doped and modified lithium iron phosphate material special for lithium ion battery and preparation method of material

Abstract

The invention discloses a doped and modified lithium iron phosphate material special for a lithium ion battery. The doped and modified lithium iron phosphate material is characterized by being prepared from the following raw materials in parts by weight: 500 parts of lithium iron phosphate, 3-4 parts of silver dihydrogen phosphate, 5-6 parts of boron carbide, 1-2 parts of lithium manganese phosphate, 4-5 parts of modified silver powder and an appropriate amount of water. As the modified silver powder is added, the conductivity of the material is enhanced and crystal growth is effectively restrained, so that the evenly-dispersed lithium iron phosphate material is obtained; besides, the doped and modified lithium iron phosphate material is high in discharge capacity, ensures the uniformity of dynamic battery industrialization as well as battery duration, and has the advantages of low price, no toxicity, no pollution to the environment, good safety, wild raw material sources, long service life and the like.

Description

technical field [0001] The invention relates to the field of chemical energy materials, in particular to a special doped modified lithium iron phosphate material for lithium ion batteries and a preparation method thereof. Background technique [0002] Lithium iron phosphate electrode materials are mainly used in various lithium-ion batteries. Compared with the traditional lithium-ion secondary battery cathode materials, LiMn2O4 with spinel structure and LiCoO2 with layered structure, LiMPO4 has wider source of raw materials, lower price and no environmental pollution. In the current existing technology, lithium iron phosphate has its unique advantages as a cathode material for lithium-ion batteries: (1) relatively high theoretical specific capacity of 170mAh / g; (2) good thermal and chemical stability; ( 3) Low cost, low toxicity and good safety performance; (4) Long cycle life. However, due to the defects of low electrical conductivity and low lithium ion conductivity of l...

AI Technical Summary

Problems solved by technology

However, due to the defects of low electrical conductivity and low lithium ion conductivity of lithium iron phosphate, the battery has poor low temperature performance and poor rate discharge performance.