Patent ID: 8658314

Claim:
A method of preparing the lithium-manganese-tin-oxide of formula (I): LiSn x/2 Mn 2−x O 4 (I) wherein, 0<x ≦0.05, the method comprising the steps of: a) mixing powders of Li, Mn and Sn compounds to obtain a mixed powder, wherein the amounts of the Li, Mn, and Sn compounds mixed together comprise 18.0 to 26.0 wt%, 72.4 to 81.9 wt%, and 0.1 to 1.6 wt%, respectively, based on the total weight of the mixed powder, and the Sn compound is selected from the group consisting of SnO, Sn(CH 3 CO 2 ) 2 , SnCl 2 , SnCl 2 ·2H 2 O, [CH 3 (CH 2 ) 3 CH(C 2 H 5 )CO 2 ] 2 Sn, SnF 2 , Sn 2 CO 4 , SnSO 4 , SnS, and a mixture thereof; b) first-milling the mixed powder; c) calcining the first-milled powder; d) second-milling the calcined powder; e) pressing the second-milled powder; and f) sintering the pressed mixture.