Fig. 4: Capacity retention in galvanostatic cycling.

Galvanostatic cycling of Prussian white – Hard carbon sodium-ion full cells at 40 °C (orange triangles) or 55 °C (blue triangles) in the left column and coulombic efficiency of the same cells in the right column. Used electrolytes were in a and b 0.35 M NaBOB in TEP, in c and d 0.35 M NaBOB in TEP + 3 wt% PES, in e and f 0.35 M NaBOB in TEP + 3 wt% DTD and in g and h 1 M NaPF6 in EC:DEC 1:1 by volume.