2 research outputs found
Facet-Dependent Rock-Salt Reconstruction on the Surface of Layered Oxide Cathodes
The surface configuration
of pristine layered oxide cathode particles
for Li-ion batteries significantly affects the electrochemical behavior,
which is generally considered to be a thin rock-salt layer in the
surface. Unfortunately, aside from its thin nature and spatial location
on the surface, the true structural nature of this surface rock-salt
layer remains largely unknown, creating the need to understand its
configuration and the underlying mechanisms of formation. Using scanning
transmission electron microscopy, we have found a correlation between
the surface rock-salt formation and the crystal facets on pristine
LiNi<sub>0.80</sub>Co<sub>0.15</sub>Al<sub>0.05</sub>O<sub>2</sub> primary particles. It is found that the originally (014Ì…)
and (003) surfaces of the layered phase result in two kinds of rock-salt
reconstructions: the (002) and (111) rock-salt surfaces, respectively.
Stepped surface configurations are generated for both reconstructions.
The (002) configuration is relatively flat with monatomic steps while
the (111) configuration shows significant surface roughening. Both
reconstructions reduce the ionic and electronic conductivity of the
cathode, leading to a reduced electrochemical performance
Facet-Dependent Rock-Salt Reconstruction on the Surface of Layered Oxide Cathodes
The surface configuration
of pristine layered oxide cathode particles
for Li-ion batteries significantly affects the electrochemical behavior,
which is generally considered to be a thin rock-salt layer in the
surface. Unfortunately, aside from its thin nature and spatial location
on the surface, the true structural nature of this surface rock-salt
layer remains largely unknown, creating the need to understand its
configuration and the underlying mechanisms of formation. Using scanning
transmission electron microscopy, we have found a correlation between
the surface rock-salt formation and the crystal facets on pristine
LiNi<sub>0.80</sub>Co<sub>0.15</sub>Al<sub>0.05</sub>O<sub>2</sub> primary particles. It is found that the originally (014Ì…)
and (003) surfaces of the layered phase result in two kinds of rock-salt
reconstructions: the (002) and (111) rock-salt surfaces, respectively.
Stepped surface configurations are generated for both reconstructions.
The (002) configuration is relatively flat with monatomic steps while
the (111) configuration shows significant surface roughening. Both
reconstructions reduce the ionic and electronic conductivity of the
cathode, leading to a reduced electrochemical performance