Solvothermal approach is used to synthesize LiMn0.9Fe0.1PO4 (LMFP) nanomaterial for Li-ion batteries (LIBs). Experimental parameters such as feeding sequences, reaction time and reaction temperature are discussed and the obtained LMFP are characterized by XRD, SEM and TEM. To understand the formation of LMFP, a reaction mechanism is proposed. The proposed mechanism indicates that the suitable concentration of M-Li (M = Fe, Mn) antisite defect can improve the electrochemical performance of the material. The charge-discharge data of obtained LMFP shows that the LiMn0.9Fe0.1PO4 material synthesized at 180 degrees C for 4 h and then sintering with sucrose at 650 degrees C for 5 h under argon protection has the highest discharge capacity, which is 149.2 mAh g(-1) at 0.1C rate. (C) 2013 Elsevier B.V. All rights reserved.