Effect of (Mg, Al) double doping on the thermal decomposition of LiMn2O4 cathodes investigated by time-resolved X-ray diffraction

• (Mg, Al) doubly doped LiMn2O4 showed better cycle retention than undoped LiMn2O4.
• Time-resolve XRD was used to investigate thermal stability of LiMn2O4.
• Mg and Al substitution improves the thermal stability of LiMn2O4.

The performance of undoped and (Mg, Al) doubly doped LiMn2O4 electrodes were compared, with the latter having better cycle retention at room temperature and enhanced cycling performance at elevated temperatures. The effect of double (Mg, Al) doping on the thermal stability of charged and uncharged samples was studied by time-resolved X-ray diffraction, revealing that Mg and Al significantly improve the structural stability of LiMn2O4 during heat treatment.