Structural, electrochemical and thermal stability investigations on LiNi0.5−xAl2xMn1.5−xO4 (0 ≤ 2x ≤ 1.0) as 5 V cathode materials

► Al-doped compounds LiNi0.5−xAl2xMn1.5−xO4 (0 ≤ 2x ≤ 1.0) with a wide doping range are prepared and characterized. ► The optimal Al concentration in the LiNi0.5−xAl2xMn1.5−xO4 is 0.05 ≤ 2x ≤ 0.10. ► The thermal stability of LiNi0.5−xAl2xMn1.5−xO4 electrodes before 225 °C is effectively improved by Al-doping.