A simple method of analyzing the phase transition behavior of a Na-Sn battery using energy-dispersive X-ray spectroscopy

Anode materials of the Na-Sn battery experience a series of phase transitions during charging and discharging. These phase transitions in many cases are accompanied by a large volume change in the electrode materials, which leads to pulverization, a major source of reducing the battery capacity. In contrast to the rich literature on the phase transition behaviors of the Li-Si battery, those of the Na-Sn battery are much less understood due to experimental difficulties in determining the chemical composition of the phases. In this study, we demonstrate a simple method of analyzing the composition of the reaction compounds of the Na-Sn battery electrodes using energy dispersive X-ray spectroscopy.