The performance of a low cost, prismatic Li-ion rechargeable battery technology based on the LiMn2O4/C cell chemistry is described and compared to a cylindrical LiCoO2/C cell. The LiMn2O4/C cell has demonstrated constant current charge, discharge and pulse discharge rate capability comparable to the more expensive LiCoO2/C technology. For simulated high power radio operation, the high power LiMn2O4/C cell offers performance comparable to the commercial LiCoO2/C cell. The cycle life demonstrated to date of the LiMn2O4/C cell, while adequate for military application, is shorter than the LiCoO2/C cell.