fig3

Figure 3. Research on anode and electrolyte for K-S batteries. (A) Hard carbon anode (Reproduced with permission from^[25]. Copyright 2018, American Chemical Society). (B) β′′-Al₂O₃ solid electrolyte (Reproduced with permission from^[24]. Copyright 2015, Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim).