We present a novel configuration for stabilizing manganese oxide as anode of high energy density lithium ion battery. Porous Mn2O3 nanocubes were developed with cubic MnCO3 as precursor and coated with a solid electrolyte interphase (SEI) by applying an electrolyte additive, prop-1-ene-1,3-sultone (PES). Discharge-charge tests demonstrate that the resulting anode exhibits excellent cyclic stability. Electrochemical and physical characterizations indicate that PES is easily reducible on Mn2O3 forming a protective SEI, which maintains the structural integrity of Mn2O3 particles. The porosity of the cubes and the SEI on the particles co-contribute to the improved cyclic stability of the resulting anode.