Synthesis and characterization of the hollandite-type MnO2 as a cathode material in lithium batteries

Hollandite-type MnO2 (HMDO) with hydronium as tunnel counter ion was synthesized by oxidation of MnSO4 with ozone in a concentrated sulfuric acid solution. Its composition and structure were analyzed and characterized by inductive coupled plasma atomic emission spectrometry (ICP-AES), titration, Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and scanning electron microscopy (SEM). Hydronium can be exchanged with hydrated lithium ion and the exchanged HMDO can be dehydrated at 300 degrees C. Cyclic voltammetry and galvanostatic charge-discharge study showed that HMDO with lithium ion exchanged and dehydrated had potential to be used as a cathode material in lithium secondary batteries. (C) 2000 Elsevier Science Ltd. All rights reserved.