Fig. 5: Corrosion-resistant and dendrite-free Cd electrode.

CEs of Cd||Cu cells in different electrolytes measured at 10 mA cm⁻² and 5 mAh cm⁻² with a NEU of 55% (a) and the corresponding Cd plating/stripping curves in 1 C6N electrolyte (b). XRD patterns of Cd electrodes in 1C and 1C6N electrolytes after cycling 10 cycles (c), SEM image in 1C6N electrolyte (d) and the schematic of stacked Cd texture (e). Aging CE test sequence (f), the corresponding voltage profiles in 1C6N electrolyte (g), and aging CEs in different electrolytes (h). Aging CE performed at a fixed plated capacity of 5 mAh cm⁻² and current density of 5 mA cm⁻², an aging time of 12 h, and then a stripped current density of 5 mA cm⁻² for per cycle with a NEU of 55% (f–h). i CEs of Cd||Cu cells in different electrolytes measured at 0.5 mA cm⁻² and 5 mAh cm⁻² with a NEU of 55%. j Voltage curves of Cd||Cd symmetric cells in different electrolytes at 0.5 mA cm⁻² and 0.1 mAh cm⁻². An average electrochemical testing temperature of 25 ± 2 °C was maintained in (a, b, f–j). XRD patterns (k) and XPS spectra of O 1s (l) of Cd electrodes after Cd plating/stripping for 229 h in Cd||Cd cells.