Facile preparation of monolithic LiFePO₄/carbon composites with well-defined macropores for a lithium-ion battery

A novel and facile method for the preparation of monolithic LiFePO ₄/carbon composites with well-defined macropores has been developed. The precursor macroporous gels consisting of inorganic networks as well as organic polymers were fabricated by the epoxide-mediated sol-gel method accompanied by phase separation. The inorganic-organic hybrid gels were calcined under an inert atmosphere, resulting in LiFePO₄/carbon monoliths. The influence of the starting compositions on the gel morphologies has been investigated, and the constituents of the gel network were discussed. The reaction mechanism of the crystallization of LiFePO₄ from green bodies during calcination has also been investigated by thermal analysis, X-ray diffraction, and Raman scattering. In addition, the electrochemical properties of the resultant LiFePO₄/carbon composites were examined by the charge-discharge test.