Composite cathodes for lithium-ion rocking-chair cells have been fabricated based on LiMn2O4 which was synthesized by a new solution route that may be carried out in air. These cathodes have been cycled in three-electrode cells at discharge and charging current densities of 1 and 0.5 mA cm-2, respectively (corresponding to a discharge rate of C/2), between limits of 4.4 and 3.3 V. The specific discharge capacity obtained initially is 110 mAhg-1 of active material decreasing by only 25 mAhg-1 to yield a capacity of 85 mAhg-1 at 300 cycles. This performance is very promising in the context of developing rechargeable lithium-ion batteries using lithium manganese oxide-based positive electrodes.