Dielectric and microwave absorption properties of LiCoO2 and its enhancement by micro-doping with metal ions

Abstract

LiCoO2 powders are the popular active cathode material in lithium batteries, but their dielectric and microwave absorption properties were seldom reported. In this work, the LiCoO2 powders were synthesized by solid-state reaction. And in order to enhance their dielectric properties, influence of metal ions micro-dopant on the electromagnetic property of LiM0.94Co0.06O2 powders (M = Mg, Zn, Ni, Mn and Y) was investigated. The phase and composition were characterized. The dielectric properties and the microwave absorption properties were evaluated. Compared to dopant of Zn, Ni, Mn and Y ions, the results showed that both the real part (e′) and imaginary part (e″) of LiM0.94Co0.06O2/paraffin mixtures were obviously increased by doping Mg ions. One layer absorbent with 75 wt% LiMg0.06Co0.94O2 content of a thickness of 1.8 mm had the optimum microwave absorption properties. The lowest reflection loss was − 36.6 dB. The results indicated that LiCoO2 and LiM0.06Co0.94O2 powders would be a possible candidate for microwave absorption materials.