An eco-efficient approach bases on a mechano-chemical liquid-phase activation technique is developed for synthesizing LiMnPO4/C composites. The fine sized [Mn-3(PO4)(2)center dot xH(2)O + Li3O4] precursors with uniform particle size distribution are prepared, and characterized by XRD and scanning electron microscope (SEM). The in situ-carbon coated LiMnPO4 composites are synthesized by one-step solid state reaction. The prepared LiMnPO4/C nano-composites show a comparable rate capability with discharge specific capacity of 136.4 mAh g(-1) at 0.05 C-rate and 118 mAh g(-1) at 1 C-rate at room temperature. The results indicate that LiMnPO4/C composites synthesize from this environmental friendly route shows a promising electrochemical activity as cathode material for lithium ion batteries. (C) 2014 Elsevier B.V. All rights reserved.