An ionically conducting block copolymer was used as a template for the synthesis and confinement of lithium manganese oxide nanoparticles. The block copolymer functions as a polyelectrolyte and as a composite anode in a lithium battery system. Impedance spectroscopy and galvanostatic testing, X-ray diffraction and transmission electron microscopy were used to characterize the anode and polyelectrolyte. Galvanostatic testing indicates 300 or more cycles were possible without appreciable capacity fade.