LAUSR

Ni-rich LiNi0.8Co0.1Mn0.1O2 (NCM811) cathode is considered to be among the most promising candidates for high-energy-density lithium-ion batteries (LIBs). However, both capacity fading and structural degradation occur during long-term cycling, which extremely limit the commercial applications of NCM811, especially at high cut-off voltage (>4.3 V). Here, we design a double-shell hybrid nanostructure consisting of a Li2SiO3 coating layer and a cation-mixed layer (Fm3(-)m phase) to improve its electrochemical performance. Consequently, the Si-modified NCM811 electrode shows outstanding cycling stability with a 95.2 % capacity retention at 4.3 V after 100 cycles and 87.3 % at 4.5 V high cut-off voltage after 100 cycles. This performed double-shell hybrid nanostructure alleviates side reactions, structural degradation, and internal cracking, effectively enhancing surface structural stability. This efficient strategy provides a valuable step towards further commercial applications of LiNi0.8Co0.1Mn0.1O2 cathode and enriches the fundamental understanding of layered cathode materials.