Simple, rapid and accurate determination of lattice composition and evaluation of electrochemical properties of LixNi2 − xO2 electrode material for lithium ion battery by a novel method

A series of lithium nickel composite oxides LixNi2 − xO2 (0  ⩽ x ⩽ 1) were synthesized and characterized by X-ray diffraction (XRD) measurement. As lithium content increases, the cell parameters decrease. It is found that the cell volume (V) and lithium content (x) have a good linear relationship which corresponds to a linear equation, V = 109.0366 − 7.6572x (R = −0.9999). The credibility of the linear relationship was confirmed by inductively coupled plasma atomic emission spectrometry (ICP-AES) analysis. The electrochemical properties of LixNi2 − xO2 (0.9 ⩽ x ⩽ 1) whose composition determined by the linear relationship were discussed. The oxide exhibits better electrochemical properties with x closing to 1. The linear relationship can be applied to determine the lattice composition and evaluate the electrochemical properties of LixNi2 − xO2 electrode materials for lithium ion battery.