Enhancing the high-voltage electrochemical performance of LiNi_0.8Co_0.1Mn_0.1O₂ cathodes through La_0.2Sr_0.8TiO₃ surface...

The highly active surface of LiNi_0.8Co_0.1Mn_0.1O₂(NCM811) cathodes frequently causes rapid surface degradation, leading to diminished cycling and rate capabilities, particularly under high voltage conditions exceeding 4.5 V. Herein, we report an approach to boost the electrochemical performance of NCM811 through integrated surface engineering. The highly conductive La_0.2Sr_0.8TiO₃(LSTO) acts as an effective protective layer to mitigate interfacial side reactions. Moreover, this coating strategy prevents the additional impedance commonly induced by standard surface treatments. After 300 cycles at 1C, the optimized N-LSTO2 cathode material exhibits a remarkably enhanced capacity retention of 88.19%, whereas the pristine NCM811 only maintains 38.73%. Additionally, the N-LSTO2 cathode exhibits a discharge capacity of 120.3 mAh g^-1 at 10C rate, which significantly outperforms the 89.6 mAh g^-1 observed for the pristine cathode. The enhanced electrochemical properties originate from the highly conductive LSTO protective barrier, which creates an amorphous layer of approximately 4 nm in thickness on the NCM811 surface. The effective separation between NCM811 and the electrolyte provided by this coating leads to the inhibition of severe interfacial side reactions, coupled with enhanced electron transfer kinetics at the electrode/electrolyte interface.