<p>The performance of lithium-ion batteries, including their maximum output power and minimum charging time, is fundamentally constrained by the efficiency of ion and electron transport. These processes are governed by the electron conductivity and ion diffusion within active electrode materials, and the ionic mobility within the electrolyte. In this work, micron-sized Nb₁₆W₅O₅₅ particles were coated with reduced graphene oxide (rGO). Simultaneously, the electrolyte was carefully engineered to further support high-rate performance. These modifications significantly improve the material’s electronic conductivity while optimizing interfacial ion diffusion. Hence, the micron-sized rGO/Nb₁₆W₅O₅₅ exhibits a high reversible capacity (&gt; 250 mAh g⁻¹ at 0.2 C) with ultra-high rate performance (≈114 mAh g⁻¹ at 80 C). In addition, the capacity of Li||rGO/Nb₁₆W₅O₅₅ pouch cell maintains 99.2% after 100 cycles at 10 C. The series-connected pouch cells can charge mobile phones through wireless charging technology. This work offers valuable insights into the interfacial engineering of electrodes, paving the way for fast-charging battery applications.</p>