Controllable synthesis of porous metal oxide films is highly desirable for high-performance electrochemical devices. In this work, a highly porous NiO film composed of interconnected nanoparticles is prepared by a simple co-electrodeposition method. The nanoparticles in the NiO film have a size ranging from 30 to 100 nm and construct large-quantity pores of 20-120 nm. As an anode material for lithium ion batteries, the highly porous NiO film electrode delivers a high discharge capacity of 700 mA h g(-1) at 0.2 C, as well as good high-rate performance. After 100 cycles at 0.2 C, a specific capacitance of 517 mA h g(-1) is attained. The good electrochemical performance is attributed to the interconnected porous structure, which facilitates the diffusion of ion and electron, and provides large reaction surface area leading to improved performance. (C) 2014 Elsevier Ltd. All rights reserved.