Electrochemical behavior
and performance of negative electrodes
in metal batteries can be modified and improved by combining different
elements. Herein, a beneficial coupling of In and Sb in the alloying
reaction with Mg was considered through the preparation of the InSb
alloy by mechanochemical synthesis. Despite a strong inactivity of
Sb as a sole element in Mg-ion batteries, the combination of Sb with
In partially unlocks the reversibility of the alloying reaction of
Sb with Mg to form Mg3Sb2. For the first time,
this beneficial effect is observed not only during the first magnesiation
but along few tens of cycles. The analysis of the behavior of InSb
through electrochemical and X-ray diffraction measurements also revealed
a more complex path than that reported in the literature. Uncommonly,
a preferential electrochemically driven amorphization of MgIn is suggested
in standard galvanostatic measurements. Crystallization of MgIn is,
however, observed through a galvanostatic intermittent titration technique,
suggesting strong kinetic effects on the microstructure, strain, or
disorder in the InSb phase upon magnesiation.