A porous cardboard separator keeps cathode and anode apart. The electricity is conducted through a carbon rod in the center of the battery. When a circuit is closed, current flows through the battery.

The full-cell configuration is similar to the half-cell other than changing the cathode to β-Ni(OH) 2 as illustrated in Fig. 4a. We confirmed the phase of β-Ni(OH) 2 by X-ray diffraction (XRD ...