Phase　transition　can　profoundly　influence　the　electrochemical　performances　of　cathode　materials　for　lithium　ion　batteries.　The　intricate　phase　transitions　upon　electrochemical　cycling　constrain　the　high-rate　performances　of　the　LiNi0.5Mn1.5O4　cathode.　The　formation　of　the　rocksalt-like　phase　causes　the　diffusion　of　Li　ions　asymmetric　in　the　lithiation　and　delithiation　reactions.　The　evolution　of　multiple　cubic　phases　results　in　poor　diffusivity　of　Li　ions　in　the　LiNi0.5Mn1.5O4.　High-resolution　XRD　scans　on　the　chemically　delithiated　samples　reveal　that　the　intricate　phase　transitions　are　effectively　suppressed　in　Cr-doped　LiNi0.5Mn1.5O4.　The　suppression　of　phase　transitions　not　only　enhances　the　Li　ions＇　diffusivity　inside　the　lattice,　but　also　stabilizes　the　charge　transfer　interfaces　by　reducing　lattice　mismatch　and　alleviating　structural　stress　during　the　lithiation　and　delithiation.　Consequently,　the　improvement　on　structure　evolution　endows　the　LiNi(0.5)Mn(1.5)O(4　)with　enhanced　diffusion　coefficient　of　Li　ions,　larger　accessible　capacity,　and　improved　Coulombic　efficiency.