Ni-rich layered oxide material with high theoretical capacity and low cost is one of the most promising cathode
candidates for high-energy-density lithium-ion battery. However, increase of Ni content triggers structural
instability and fast capacity degradation, which severely impedes the practical application of Ni-rich materials.
Here, a surface dual-modification layer of B2O3 & LiBO2 is introduced to Ni-rich material LiNi0.89Co0.08Mn0.03O2
(NCM89), which successfully stabilizes the layered structure of NCM89 during cycling as well as removes re-
sidual lithium in NCM89. The in-situ X-ray diffraction and cross-sectional scanning electron microscopy results
demonstrate effectively improved structural reversibility and stability of the cathode. Moreover, the dissolution
of transition metals and decomposition of electrolyte at the cathode/electrolyte interface are successfully sup-
pressed, resulting in beneficial cathode electrolyte interphase (CEI) layer. As a result, the boron modified cathode
exhibits s a high capacity of 180.4mAh g 1
along with an excellent capacity retention of 90% after 100 cycles at
1C in 2.75–4.35 V at 25
?
C, while the pristine NCM89 cathode only retains 59% of its initial capacity after 100
cycles. Furthermore, the capacity retention of full cell after 350 cycles is improved from 52.5% to 90%.