Rod-shaped, elongated and cubic nanoparticles of LiMnPO4 were synthesized. The shape of LiMnPO4 altered the 1D diffusion direction of Li+. Particles with the shortest dimension along the b-axis possessed the highest DLi+. The shape of LiMnPO4 affected its tap density. The volumetric capacity of LiMnPO4 increased via the formation of dense composite.