Preparation, structure and electrochemical properties of spinel Li1-xMn2-yO4 cathode material for lithium ion batteries

The spinel LiMn2O4 has been synthesized at low temperature from polymeric p recursors through Pechini process. In combination with element content dete rmination and valence evaluation, auto-calibration method has firstly been introduced to calculate the amounts of LiMn2O4 with spinel and Mn2O3 with b ixbyite in the species, and then metal-deficient nonstoichiometric model of [Li(1-x)square(x)](8a)[Mn(III)(p)Mn(IV)(q)square(y)]O-16d(4) has been prop osed to describe the structure of the prepared sample. Electrical propertie s of LiMn2O4 have been depicted by charging and discharging curves and cycl ic voltammograms. When calcining temperature is at 500 degrees C, vacancy a mounts of Li+ ion in the defect model is 0.3, that of Mn is 0.1 and capacit y of the material is 127.8 mAh g(-1). (C) 2000 Elsevier Science B.V. All ri ghts reserved.