Li-rich　layered　oxides　(LLOs)　are　supposed　to　be　the　most　competitive　cathode　materials　for　lithium-ion　batteries　(LIBs),　because　of　the　high　theoretical　specific　capacities　(＞250　mAh　g(-1)).　However,　there　are　some　inherent　inferiorities,　such　as　the　low　initial　Coulombic　efficiency　(ICE)　and　the　rapid　capacity/voltage　decay,　that　hinder　the　large-scale　commercial　applications　of　LLOs.　Herein,　we　successfully　obtained　spinel-coated　and　phosphate-doped　Co-free　Li-rich　layered　oxides　(Co-free　LLOs)　by　cotreatment　methods,　using　weakly　acidic　and　alkalinity　(NH4H2PO4　solution),　which　could　effectively　improve　the　electrochemical　performance.　The　spinel　coating　could　not　only　accelerate　the　movement　of　Lit　but　also　restrain　O-2　release,　while　the　doping　PO43-　could　inhibit　the　transition-metal　(TM)　migration　between　the　oxygen　octahedral　site　and　the　oxygen　tetrahedral　site.　The　optimized　Co-free　LLOs　cathode　treated　with　3%　NH4H2PO4　solution　could　deliver　a　high　ICE　of　88%　and　a　high　discharge　capacity　up　to　159.5　mAh　g(-1)　after　500　cycles　at　1C　(1C　=　250　mA　g(-1)).　Moreover,　the　voltage　fading　decreases　from　0.64　mV　to　0.32　mV　per　cycle　during　cycling.　This　work　provides　new　insights　for　developing　high-performance　Co-free　LLOs　cathode　materials.