Spinels of composition LiM Y Mn2−Y O4, M=Cr3+, Co3+, or Ni2+, Y =0.1 and 1 for the Cr and Co dopants, Y =0.05 and 0.5 for the Ni sample, have been synthesized by a sucrose-aided combustion method. The samples as prepared require of an additional thermal treatment at 700°C, 1h to get stoichiometric single-phase spinels. The samples consist of aggregated particles of small size (45–50nm) as deduced from transmission electron microscopy and X-ray powder diffraction. The electrochemical behaviour of the six spinels as cathodes in lithium cells has been analysed at 5 and 4V under high current, 1C rate. At 5V the discharge capacity of LiNi0.5Mn1.5O4 is higher than the one shown by LiCrMnO4 and LiCoMnO4, and it shows an elevated cyclability, i.e. capacity retention of 85.3% after 100 cycles. At 4V the discharge capacity is similar for LiNi0.05Mn1.95O4, LiCr0.1Mn1.9O4 and LiCo0.1Mn1.9O4, and all the three spinels show similar and very high cyclability, i.e. capacity retention >90% after 100 cycles. The spinels preserve their starting capacity up to currents as high as 2C rate. The nanometric size of the samples explains the high rate capability of the synthesized spinels.