Electrochemical lithiation of Ti5M3, Ti3M and Zr3M (M = Sn, Sb) binary intermetallics

 

Chem. Met. Alloys 9 (2016) 84-91

 

Vasyl KORDAN, Oksana ZELINSKA, Volodymyr PAVLYUK, Igor OSHCHAPOVSKY, Roman SERKIZ

 

The binary phases Ti5M3, Ti3M and Zr3M (M = Sn, Sb) were studied for electrochemical lithiation, using powder X-ray diffraction, scanning electron microscopy (SEM) and energy-dispersive X-ray analysis (EDX). The investigation showed that the morphology of the cathode and the anode surfaces undergo changes, and the grain size of the materials decreases. The phase analysis of the anode materials revealed that the Ti5Sn3 (structure type Mn5Si3) and Ti3Sn (structure type Mg3Cd) phases form solid solutions by insertion of Li atoms into the initial structure. The insertion is reversible. The phases Ti5Sb3 (structure type Y5Bi3), Ti3Sb, Zr3Sn (structure type Cr3Si), and Zr3Sb (structure type Ni3P) form solid solutions by substitution of Li for Sn or Sb atoms. Only the Zr3Sb phase showed weakly reversible substitution. Among the investigated compounds, the most suitable structure types for intercalation of lithium appeared to be the Mn5Si3- and Mg3Cd-types, where the Li atoms occupy octahedral voids. The intermetallic compounds containing tin showed better ability for electrochemical lithiation than the compounds containing antimony. This can be explained by the easier interaction of antimony and lithium with the formation of binary compounds.

 

 

Projection of the unit cells of Ti5Sn3Lix (a) and Ti3SnLix (b).

 

Keywords

Intermetallic compound / Electrochemical lithiation / Li-ion battery