Hard Carbon Microspheres: Potassium‐Ion Anode Versus Sodium‐Ion Anode

Hard carbon microspheres (HCS) exhibit a highly reversible capacity of 262 mAh g−1 for K-ion batteries. They present a superior rate capability for K-ions to Na-ions, where at 2C, HCS/K cells deliver 190 mAh g−1 in contrast to 97 mAh g−1 from HCS/Na cells. It is determined that the K-ion diffusion coefficient of HCS is higher than that of Na-ions. As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer reviewed and may be re-organized for online delivery, but are not copy-edited or typeset. Technical support issues arising from supporting information (other than missing files) should be addressed to the authors. Please note: The…