A 3V lithium-ion cell with Li[Ni1/2Mn3/2]O4 (Fd 3 ̄ m; a=8.17Å) and the zero-strain insertion material of Li[Li1/3Ti5/3]O4 (Fd 3 ̄ m; a=8.36Å) was examined with an emphasis on rate-capability and cycle life. This cell showed a quite flat operating voltage of 3.2V with excellent cycleability. Accelerated cycle tests indicated that 83% of the initial capacity was delivered and stored even after 1100 cycles. Although the calculated energy density of a Li[Li1/3Ti5/3]O4/Li[Ni1/2Mn3/2]O4 cell was about 250Whkg−1 or 1000Whdm−3 based on the active material weight or volume, the 3V lithium-ion battery exhibited positive characteristic features, such as flatness in operating voltage, high rate capability, and cycle life.