Based on the performance of hydrotalcite as anode material for a Zn–Ni secondary cell, a modification: PPY coated Zn–Al–LDH was adopted

Polypyrrole-coated, layered double hydroxide was successfully synthesized by the polymerization of pyrrole in the slurry of hydrotalcite under ultrasonication and stirring. The structure and morphology of PPY-LDH composites were confirmed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) and the results indicate that the PPY was successfully coated onto the surface of the Zn-Al-LDH. The electrochemical performance of the PPY-LDH composites as the electrode has been evaluated for the Zn-Ni secondary cell, which proves their exceptional reversibility and superior cycle stability. Besides, the results of the electrochemical impedance spectroscopy (EIS) test indicate that PPY modification improves the conductivity of the anode and decreases the charge transfer resistance of the electrode, which greatly enhances the electrochemical performance of the PPY-LDH composites.