A kind of multi-component doped lithium phosphate cathode material and preparation method thereof, and lithium ion power battery

Abstract

The invention relates to a multi-doped lithium phosphate anode material for a lithium ion power cell, LiFe1 minus x minus y Ti0.5x Mn0.1 minus y PO4 as base material is clad by a carbon material particle layer, the base material and the carbon material particle layer are combined to form composite particles, the composite particles are evenly dispersed in the conductive network of carbon materialparticles, wherein x / 2 plus y is larger than or equal to 0.03 and less than or equal to 0.10, x is larger than or equal to 0.02 and less than or equal to y, y is less than or equal to 0.08, organic carbon source compound is decomposed to produce C, and the added amount of the organic carbon source compound is 1 to 10 percent of the total weight of the base material; the average grain size of the composite particles is between 0.5Mu m and 5Mu m, and the diameter of the carbon material particle is between 5nm and 50nm; and the specific surface area of the composite particle is 12m<2> / g to 35m<2> / g. The anode material has the advantages of good high-rate performance, good product consistency and good cell processability, and the power cell adopting the material as anode material has the advantages of high safety performance, high rate performance and high cycle performance.

Description

technical field [0001] The invention relates to a positive electrode material for a lithium ion battery, a preparation method thereof, and a lithium ion battery. More specifically, the present invention relates to a multi-component doped lithium phosphate positive electrode material and a preparation method thereof, and a lithium ion battery using the material. Power Battery. Background technique [0002] With the rapid development of the electronics and information industries, a large number of new mobile electronic consumer products are constantly coming out, which puts forward urgent requirements for independent power sources, especially high-energy secondary batteries. Compared with other secondary batteries, lithium ion batteries have high volumetric energy density and gravimetric energy density. Coupled with the advantages of design flexibility, long cycle life, no memory effect, low self-discharge rate, and no pollution to the environment, it has become the main choi...

AI Technical Summary

Problems solved by technology

[0006] CN100431207C discloses a binary, ternary and quaternary lithium phosphate, but its examples only disclose lithium phosphate comprising LiFeMn ternary (Example 2), and the specific capacity of the disclosed lithium phosphate is still low, and the cycle performance is also poor

[0007] CN100448071C discloses a lithium battery positive electrode material, which discloses the use of transition group elements to participate in lithium iron phosphate to form multiple lithium phosphate positive electrode materials, which can be discharged above 0.5C The capacity is lower than 130 mAh / g (although it is claimed that its theoretical specific capacity is higher than 240 mAh / g), and the cycle performance is poor (0.5C600 experiments, the specific capacity retention rate is lower than 80%)

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