FIGS. 14A, 14B, and 14C are plots showing the electrochemical performance of Zn//NiCo batteries of FIG. 8A including the PANa polyelectrolyte of FIG. 1 with different contents of Zn²⁺+OH^?;

FIGS. 15A, 15B, and 15C are plots showing the electrochemical performances of Zn//NiCo batteries using PVA-KOH electrolyte at liquid state with and without Zn²⁺;

FIGS. 16A and 16B are plots showing the electrochemical performances of solid-state Zn//NiCo batteries with PANa (solid) and PVA (dashed) as electrolytes with identical contents of water (81.1%), Zn(CH₃COO)₂ (0.065 M) and KOH (1.95 M);

FIGS. 17A and 17B are plots showing the cycling performances and the corresponding Coulombic efficiency at C rate of the Zn//NiCo battery including the PANa polyelectrolyte of FIG. 1 and PVA electrolyte respectively, when exposed in air without packaging;

FIGS. 18A, 18B, 18C, and 18D are plots showing the discharge performances of the Zn//NiCo battery before and after standstill at the open circuit state;

FIG. 19 is a plot showing the cycling performance and the corresponding Coulombic efficiency at 96 C rate of the Zn//NiCo battery with the PANa polyelectrolyte of FIG. 1 after the 7-day standstill at the open circuit state;