Novel synthesis of Mn3(PO4)2·3H2O nanoplate as a precursor to fabricate high performance LiMnPO4/C composite for lithium-ion batteries

Abstract

Mn₃(PO₄)₂·3H₂O precursor was synthesized by a novel precipitation process using ethanol as initiator, and was lithiated to LiMnPO₄/C composite via a combination of wet ball-milling and heat treatment. The as-synthesized precursor was plate-shaped with nanosize thickness. After heat treatment of the ball-milled mixture of Mn₃(PO₄)₂·3H₂O, NH₄H₂PO₄, Li₂CO₃ and glucose, the well crystallized and highly pure LiMnPO₄ with the particle size of about 100 nm and the carbon coating layer of 2 nm was obtained. The LiMnPO₄/C composite fabricated at 650 °C delivers discharge capacities of 141.7 mA h g⁻¹ at 0.05C, 119.9 mA h g⁻¹ at 1C and 88.7 mA h g⁻¹ at 5C. Meanwhile, it can retain 95.2% of the initial capacity after 100 cycles at 0.5C, revealing a quite good cycling stability. The method described in this work could be helpful in the development of LiMnPO₄/C cathode materials for advanced lithium-ion batteries.