Zn-doped Mn spinel was investigated for its unique 5 V reversible Li intercalation. Only at a certain Zn doping, LiZn0.25Mn1.75O4, lithium ions can be extracted at 5 V, while at high Zn doping of LiZn0.5Mn1.5O4 no reversible capacity was observed. Electrochemical extraction of lithium ions during charge at 5 V is partially reversible. The two Zn doped compositions (x = 0.25 and 0.5 in LiZnxMn2-xO4) have a single phase cubic spinel structure, possessing a primitive cubic atomic arrangement, in contrast to the face centered cubic LiMn2O4 spinel. All materials synthesized have a tetradecahedra grain structure, bonded via the hexagon facets. (C) 2005 The Electrochemical Society.