Layered Li[Li0.15Ni(0.275−x/2)Al x Mn(0.575−x/2)]O2 materials were synthesized via a sol–gel method at 900°C in air. Li[Li0.15Ni(0.275−x/2)Al x Mn(0.575−x/2)]O2 and Li2MnO3 phase mixed compounds were obtained. Substitution of Al3+ ions were shown to prevent the structural degradation of the electrode material allowing higher discharge capacities. The 6mol% aluminum-doped Li[Li0.15Ni0.245Al0.06Mn0.545]O2 electrode delivered approximately 210mAhg−1 discharge capacity in a cut-off range between 2.5 and 4.6V. It was found that the Al doping on Li[Li0.15Ni(0.275−x/2)Al x Mn(0.575−x/2)]O2 material could decrease the area specific impedance (ASI).