Synthesis, electrochemical, and microstructural study of precursor-derived LiMn_2O_4 powders

摘要

Stable and homogeneous alkoxide precursor solutions of lithium ethoxyethoxide and manganese ethoxyethoxide in 2-ethoxyethanol were synthesized by ligand exchange reaction of lithium isopropoxide and manganese 2-ethoxide, respectively, with 2-ethoxyethanol. [Li-Mn-O] precursor solution was prepared by mixing these modified alkoxide precursor solutions. LiMn_2O_4 powders were successfully synthesized by pyrolysis of the [Li-Mn-O] precursor powder in O_2 temperature as low as 200 ℃. The nanocrystalline LiMn_2O_4 powders 20-50 mm in diameter after heat treatment up to 700 ℃ consisted of the ordered (111) plane and performed with good cyclability as the cathode materials for Li secondary batteries.