• SnO 2 @PANI anodes were successfully synthesized through wet-chemical approach. • Anodic nanoporous SnO 2 leads to shortened lithium ion diffusion lengths. • Uniformly deposited PANI onto nanoporous SnO 2 serves as an effective buffer layer. • Optimized thickness of PANI layer is controlled by adjusting the scan rate. Herein we report a wet-chemical process to obtain binder-free anodes for lithium-ion batteries (LIBs) using a straightforward and easily scalable approach. Electrochemical deposition, anodization, and electropolymerization are used to firmly attach a nanoporous and flexible SnO 2 film, uniformly coated with polyaniline (PANI), onto a Cu substrate. The three-dimensional, flexible, and nanoporous SnO 2 @PANI electrodes exhibit good specific capacity, capacity retention, and charge transfer resistance. Its favorable electrochemical properties are attributed to the large surface area, high electrical conductivity, and effective reduction of volume expansion. These results demonstrate that the proposed approach to forming SnO 2 @PANI electrodes is a promising strategy for constructing high-performance binder-free anodes for emerging flexible LIBs.