Li1+y-xZnxMn2-yO4 spinel has been synthesized using LiOH, Zn(NO3)(2), and MnO2. The substitution of Zn2+ for Li+ in the tetrahedral 8a site of spinel was successfully achieved by adjustment of the synthetic conditions, such as atmosphere and cooling rate. The performance of 8a site Zn-doped spinel was investigated in the terms of initial capacity and polarization.