A simple, reproducible, and versatile procedure for synthesizing mesostructured 12-phosphotungstic acid thin films with large spaced mesostructures (<17 nm) using amphiphilic block copolymers as structure-directing agents is reported. The morphology of the mesostructure can be controlled by adjusting the m/n ratio of poly (ethylene oxide) 1/2 /poly (propylene oxide) (EO 1/2 /PO) in the tri-block copolymer (EO) m (PO) n (EO) m . This synthetic approach was adapted to prepare mesoscopically ordered heteropoly oxometalates (HPOMs) films, including 12-phosphomolybdic acid and 12-tungsto (IV) silicic acid. The electrochemical properties of the calcined HPOMs films as electrodes in Li-ion batteries were also investigated.