Correlation of aluminum doping and lithiation temperature with electrochemical performance of LiNi1-xAlxO2 cathode material

Abstract

This article presents a process for producing LiNi1-xAlxO2 (0 < × < 0.05) cathode material with high capacity and enhanced cycle properties of 145 mAh/g after 600 cycles. The LiNi1-xAlxO2 (0 < × < 0.05) cathode material is prepared by mixing coprecipitated Ni(OH)2 with LiOH and Al(OH)3, followed by lithiation at temperature range of 650–710 °C, after which any residual lithium from lithiation is washed from the particle surfaces. Electrochemical performance was studied within full-cell and half-cell application; in addition, different material characterization methods were carried out to explain structure changes when certain amount of aluminum is introduced in the LiNi1-xAlxO2 structure. Surface analyses were carried out to demonstrate how washing process changes the chemical environment of the LiNi1-xAlxO2 secondary particle surface. The results demonstrate how Al doping, lithiation temperature, and the washing process affect the performance of the LiNi1-xAlxO2 cathode material.