Mg2Sn as a new lithium storage intermetallic compound

To obtain a new anode material of lithium battery, electrochemical properties were investigated on Mg2Sn intermetallic compound synthesized by mechanical alloying (MA) method. As a result, we found that the reversible insertion-extraction of a large amount of lithium can electrochemically occur in mechanically alloyed Mg2Sn. The Mg2Sn changed its own crystal structure from cubic to orthorhombic with increasing MA time. The compound exhibiting good performances as an anode had a mixture of cubic and orthorhombic phases. The discharge capacity of the Mg2Sn electrode was still maintained at 250-300 mA h g(-1) even after the 20 times charge-discharge cycling. The reaction proceeded without any phase separation and/or decomposition of the compound. Mg2Sn would be a promising anode material for lithium secondary batteries.