Bismuth (Bi)-based electrodes are highly attractive for potassium-ion batteries (PIBs) while suffering from a short cycle life due to the larger diameter of K ion, leading to unstable solid electrolyte interface (SEI) films during continuous potassiation/depotassiation. Herein, we developed novel ultrathin carbon film@carbon nanorods@Bi nanoparticle (UCF@CNs@BiN) materials for the long cycle life anode of PIBs. Bi nanoparticles are uniformly distributed in carbon nanorods, which not only provides a high-speed channel for ion transport but also accommodates the volume change of Bi nanoparticles during continuous potassiation/depotassiation processes. The UCF@CN matrix can direct most SEI film formation on the surface of the carbon film, not on the surface of individual Bi nanoparticles, avoiding the fracture of the matrix. Benefiting from their unique structure, the UCF@CNs@BiN anodes exhibit an outstanding capacity of ∼425 mAh g–1 at 100 mA g–1 and a capacity decay of 0.038% per cycle over 600 cycles. Even at a higher current density of 1000 mA g–1, there is a capacity decay as low as 0.036% per cycle during 700 cycles. Meanwhile, this work provides a new way of utilizing the metal–organic framework structure and reveals a highly promising PIB anode.

Antimony‐based electrodes have great application prospects for high‐power potassium‐ion batteries (PIBs) due to their low platform and high capacity, while suffering from limited cycle stability and severe pulverization phenomenon. Herein, commercial graphite and antimony powder are utilized to prepare antimony–graphite composites via ball‐milling along with ultrasonic processing. As a result, the antimony‐cluster can embed into the graphite layer and form antimony interspersed graphite composites, which is beneficial to accommodate the volume expansion and degeneration phenomenon of antimony. Consequently, the antimony–graphite composite can deliver high‐reversible capacity (524 mA h g−1 at 50 mA g−1), superior capacity retention (96.8% after 100 cycles), and an excellent rate performance (340 mA h g−1 at 1000 mA g−1). This work paves the way to design high‐performance alloy‐type anode materials for PIBs.