Spinel lithium manganese oxide (LiMn 2 O 4) based Li-ion battery (LIB) is attractive for hybrid/full electric vehicles because of its abundant resources and easy preparation. However, operation under an elevated temperature could cause severe capacity fading of the spinel cathodes. In this work, 1, 3-propane sultone (PS) is investigated as an electrolyte additive for improving the cyclability of the LiMn 2 O 4 /graphite LIB at elevated temperature. The charge and discharge measurement proves that PS can significantly enhance the cyclability of 053048-type LiMn 2 O 4 /graphite pouch cell at 60 • C. Compared to the cell without additive, the capacity retention of the cell using electrolyte with 5% PS increases from 52 to 71% after 180 cycles. The improved cyclability is attributable to the modification of the solid electrolyte interface (SEI) on both positive and negative sides of the LiMn 2 O 4 /graphite cell by PS, which effectively prevents anode and cathode from structural breakdown and inhibits the electrolyte decomposition.