Extremely Durable K‑Ion Batteries Enabled by\nHeteroatom Co-Doped Highly-Ordered Porous Carbon Spheres with Nearly\n100% Capacity Retention up to 11,000 Cycles

Currently,\none major target for exploring K-ion batteries (KIBs)\nis enhancing their cycle stability due to the intrinsically sluggish\nkinetics of large-radius K<sup>+</sup> ions. Herein, we report a rationally\ndesigned electrode, the S/O co-doped hard carbon spheres with highly\nordered porous characteristics (SPC), for extremely durable KIBs.\nExperimental results and theory calculations confirm that this structure\noffers exceptional advantages for high-performance KIBs, facilitating\nrapid K<sup>+</sup> diffusion and (de)-intercalation, efficient electrolyte\npenetration and transport, improved K<sup>+</sup> storage sites, and\nenhanced redox reaction kinetics, thus ensuring the long-term cycle\nstability. As a result, the as-constructed SPC anode delivers a high\nreversible capacity of ca. 200 mAh g<sup>–1</sup> at a high\ncurrent density of 2.0 A g<sup>–1</sup> and robust stability\nwith ∼100% capacity retention up to 11,000 cycles, outperforming\nmost carbon-based KIB anodes. This work offers insight into developing\nadvanced KIBs with durable stability toward practical applications.