
Promises and challenges of alloy-type and conversion-type anode
The four voltage plateaus observed during the sodiation process attributed to formation of four two-phase materials. Therefore, Ellis et al. suggested that four Na-Sn binary alloys were formed but actually only the full-sodiated product of Na 15 Sn 4 was detected by XRD because other Na-Sn alloys are unstable or amorphous.









































