| LiCoO2 is prepared by citric acid sol-gel method. It was found that using citric acid allowed separation the nucleation and growth processes of the crystals by control of sol-time and firing temperature by sol-gel method, and therefore LiCoO2 with uniform particle and controllable scope can be prepared. The basic reaction course is illustrated by thermo-gravimetric analysis and differential thermal analysis using a PCT-IA thermal analyzer system (TG-DTA), powder XRD and SEM techniques, etc. Their structures and morphologies, electrochemical performance of the active material are investigated detailedly by powder XRD, SEM techniques, laser granularity analyzer, ICP, electrochemical workstation, Land BT1-10 test system. It was found the sample firing at high temperature (≥800℃) possessed perfect structure and excellent capability, but the sample firing at low temperature (≤600℃) was amorphous, though the first charge capacity is rather high, circular reference was too bad because of non-perfect structure.In order to improve the electrochemical performance of LiCoO2, the majorities of researchers are working on the adjustment and substitution of the lay element, in order to increase the extract and deintercalated quantity and overcharge-resistant ability, the method pillaring in the interbed is brought forward for strengthening the structure stability. The possibility K+, Na+, Ca2+, Ag+ can be pillared into the interbed is investigated by powder XRD, ICP, melting salt ion-exchange method and charge-discharge test, etc. It was found K+, Ca2+ can be pillared into interbed, but Na+, Ag+ can't. The effect pillared K+ is small and Ca2+ is remarkable. The principle ion-pillared was explored in a nutshell.
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