Electrolyte modification method for improving working voltage and cycling stability of LiCoO2 cathode materials

Abstract

The invention relates to an electrolyte modification method for improving the working voltage and cycling stability of LiCoO2 cathode materials, which belongs to the technical field of chemical electrode material manufacturing processes. In an argon glove box, a LiPF6 / ternary electrolyte is configured; Li2CO3 is added; LiCoO2 and Super. P are mixed with a polyvinylidene fluoride solution in certain proportion so as to obtain a mixture, the mixture is uniformly coated on an aluminum foil so as to prepare a composite electrode, a battery is assembled in the argon glove box, and the electrolyte is absorbed by using a dropper and added into a button battery; after the battery is completely assembled, the battery is standing for aging so as to obtain a LiCoO2 button battery; and the battery is subjected to charging and discharging testing under a high working voltage of 4.5V at room temperature so as to evaluate the cycling stability of the battery and calculate the capacity retention rate of the battery. The invention relates to an electrolyte modification method for lithium ion batteries, which improves the working voltage and cycling stability of LiCoO2 cathode materials.

Description

technical field [0001] The present invention relates to improving LiCoO 2 Electrolyte modification method for positive electrode material working voltage and cycle stability, which can improve LiCoO 2 The invention relates to a method for modifying electrolyte solution for lithium-ion batteries, which improves the working voltage of positive electrode materials and improves the cycle stability, and belongs to the technical field of chemical electrode material manufacturing technology. Background technique [0002] Today's electronic consumer market requires lithium-ion batteries to have higher specific energy to meet its needs and development, such as portable electronic devices, industrial applications and power tools. Especially for the application of electric vehicles, the energy density of lithium-ion batteries is required to be higher than 150Wh Kg -1 , which has inspired people to explore and develop battery cathode materials that can provide higher energy densities....

AI Technical Summary

Problems solved by technology

Moreover, a large amount of solvent will oxidize on the surface of the highly oxidized electrode material, resulting in an increase in the thickness of the SEI film, an increase in impedance, and inhibition of Li + The rate of crossing the SEI membrane leads to a severe fading of the electrode capacity

Therefore, although LiCoO 2 The theoretical capacity is 272mAh g -1 , but its actual usable capacity is ~140mAh g -1

Images