-- 3 - METHOD FOR MANUFACTURING COMPOSITE INCLUDING Sn-Sb COMPOUND AND TRANSITION METAL CARBIDE USING TERNARY TRANSITION METAL-Sn-Sb ALLOY AS PRECURSOR AND NEGATIVE ELECTRODE MATERIAL FOR SECONDARY BATTERY HAVING THE COMPOSITE MANUFACTURED THEREBY

摘要

The present invention relates to a method of manufacturing a tin-antimony compound and a transition metal carbide. The method includes: a step (a) of manufacturing a ternary transition metal-tin-antimony alloy including tin (Sn), antimony (Sb), and transition metal; a step (b) of mixing carbon (C) powder with powder of the ternary transition metal-tin-antimony alloy; and a step (c) of manufacturing a composite containing a tin-antimony intermetallic compound and a transition metal carbide by applying mechanical energy to the mixed powder. According to the present invention, the composite, which is made by using the ternary transition metal-tin-antimony alloy as a precursor and making a reaction to carbon, contains a transition metal carbide functioning to relieve expansion in volume of a cathodic active material particles and SnSb, which comprises finer grains than a tin-antimony compound (SnSb) manufactured through a conventional process, and thus, the expansion in volume of the cathodic active material, which occurs due to the existence of the transition carbide and a reduction in grain size of SnSb, helps to solve a capacity loss caused by a change of the volume of the cathodic active material, and therefore, the cathodic active material with an improved life cycle and high capacity is able to be beneficially used for a secondary battery.