Transparent (x = 0, 0.3, 0.5, 0.6, 0.7, 0.8, and 0.9 in molar fraction) thin films on indium‐tin oxide (ITO)/glass substrates were made by sol‐gel dip‐coating. The iron‐ion‐containing sols were prepared from and precursors. The electrochemical investigation of the ion storage process in films has been made in a cell between −1.5 and 1.0 V potential range vs. saturated calomel electrode (SCE). The total electric charge inserted and extracted during a cycle has been determined by the cyclic voltammetry. The electric charge transition ability is mainly influenced by the composition and thickness of films, heat‐treatment temperature, and the precursor concentration of sols. In a pure iron oxide system, amorphous exhibited better Li+ ion storage behavior than α‐ phase. In the composite systems, films showed the best reversibility of the insertion‐deinsertion process while their maximal Q/d value is about 0.12 mC cm−2 nm−1.