The electrochemical performances of Zn-Sn-Al-hydrotalcites in Zn-Ni secondary cells

摘要

Zn-Sn-Al-hydrotalcites (LDHs) have been successfully prepared by hydrothermal method and applied as a novel anodic active material in Zn-Ni secondary batteries. The scanning electron microscopy (SEM), X-ray diffractometer (XRD) and FT-IR tests are performed to investigate the morphology and micro-structure of Zn-Sn-Al-hydrotalcites. Electrochemical performances of Zn-Sn-Al-hydrotalcites with different Zn/Sn/Al molar ratios are investigated through galvanostatic charge-discharge measurements, cyclic voltammograms (CV) and Tafel polarization curves. Compared with Zn-Al-LDH without Sn addition, Zn-Sn-Al-LDHs still present hexagon layer structure, and present more excellent electrochemical performance. And Zn-Sn-Al-LDH with the molar ratio of 2.8:0.2:1 shows a better cycle stability than the other samples. The results demonstrate that Sn addition can help to perfect the electrochemical performance of zinc electrode with Zn-Sn-Al-LDHs. At the same time, CV tests indicate well reversibility and Tafel curves reveal more positive corrosion potential for Zn-Sn-Al-LDHs.