Nickel-rich
layered oxides have been regarded as a potential cathode
material for high-energy-density lithium-ion batteries because of
the high specific capacity and low cost. However, the rapid capacity
fading due to interfacial side reactions and bulk structural degradation
seriously encumbers its commercialization. Herein, a highly stable
hybrid surface architecture, which integrates an outer coating layer
of TiO2&Li2TiO3 and a surficial
titanium doping by incorporated Ti2O3, is carefully
designed to enhance the structural stability and eliminate lithium
impurity. Meanwhile, the surficial titanium doping induces a nanoscale
cation-mixing layer, which suppresses transition-metal-ion migration
and ameliorates the reversibility of the H2 → H3 phase transition.
Also, the Li2TiO3 coating layer with three-dimensional
channels promotes ion transportation. Moreover, the electrochemically
stable TiO2 coating layer restrains side reactions and
reinforces interfacial stability. With the collaboration of titanium
doping and TiO2&Li2TiO3 hybrid
coating, the sample with 1 mol % modified achieves a capacity retention
of 93.02% after 100 cycles with a voltage decay of only 0.03 V and
up to 84.62% at a high voltage of 3.0–4.5 V. Furthermore, the
ordered occupation of Ni ions in the Li layer boosts the thermal stability
by procrastinating the layered-to-rock salt phase transition. This
work provides a straightforward and economical modification strategy
for boosting the structural and thermal stability of nickel-rich cathode
materials.