Lithium-rich　layered　oxides　(LLOs)　with　high　energy　density　and　low　cost　are　regarded　as　promising　candidates　for　the　next-generation　cathode　materials　for　lithium-ion　batteries　(LIBs).　However,　there　are　still　some　drawbacks　of　LLOs　such　as　oxygen　instability　and　irreversible　structure　reconstruction,　which　seriously　limit　their　electrochemical　performance　and　practical　applications.　Herein,　the　high-valence　Ta　doping　is　proposed　to　adjust　the　electronic　structures　of　transition　metals,　which　form　strong　Ta-O　bonds　and　reduce　the　covalency　of　Ni-O　bonds,　thereby　stabilizing　the　lattice　oxygen　and　enhancing　the　structural/thermal　stabilities　of　LLOs　during　electrochemical　cycling.　As　a　result,　the　optimized　Ta-doped　LLO　can　deliver　a　capacity　retention　of　80%　and　voltage　decay　of　0.34　mV　cycle−1　after　650　cycles　at　1C.　This　study　enriches　the　fundamental　understanding　of　the　electronic　structure　adjustment　of　LLOs　and　contributes　to　the　optimization　of　LLOs　for　high-energy　LIBs.　©　2023　The　Authors.　Battery　Energy　published　by　Xijing　University　and　John　Wiley　&　Sons　Australia,　Ltd.