Orthorhombic LiMnO2 (o-LiMnO2) and doped Lix[CoyMn(1-y]O2 (y= 0.1, 0.3, 0.5) have been prepared from layered precursor by the method of in situ oxidation-intercalation for use as cathode materials in lithium-ion batteries. And a series of spinel MFe2O4 (M= Ni, Co, Ni-Zn, Zn) have been synthesized from layered double hydroxides (LDHs) precursors for use as anode materials in lithium-ion batteries. Reaction conditions, mechanisms, the relationships among structure, composition and electrochemical properties of materials were characterized by means of XRD, in situ HT-XRD, ICP, 7Li-MAS-NMR, FT-IR, TG-DTA-DTG-EGMS, TEM, HR-TEM and electrochemical testing. The factors which affect the electrochemical properties of materials were investigated.Using Mn(OH)2 as the precursor, (NH4)2S2O8 as the oxidant and LiOH as the lithiating reagent, nanosized o-LiMnO2 with high purity have been obtained by in situ oxidation-intercalation method. The o-LiMnO2 has a high capacity with an initial charge capacity of 243 mAh.g-1 an initial discharge capacity of 220 mAh.g-1 and a good cycling performance with a reversible capacity of 192 mAh.g-1 after 30 cycles.
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