1 research outputs found
Evolution of Spinel LiMn<sub>2</sub>O<sub>4</sub> Single Crystal Morphology Induced by the Li<sub>2</sub>MnO<sub>3</sub> Phase during Sintering
The most severe problems for adoption of LiMn2O4 (LMO) as a low-cost and sustainable cathode in lithium-ion
batteries are manganese dissolution and structural degradation, especially
at an elevated temperature. Developing large single crystals (SCs)
for LMO could be a feasible solution since it significantly reduces
electrode/electrolyte interfaces where degradation can occur, while
exceptionally high ionic diffusivity of its spinel structure could
guarantee decent kinetics. In this work, we discovered a unique correlation
between morphology and synthesis conditions, especially oxygen partial
pressure in a successful development of defect-free faceted LMO SCs.
Further experimental and theoretical studies identified that crystal
growth of spinel LMO can be dramatically promoted by the Li2MnO3 impurity, which is spontaneously generated at low
oxygen partial pressure during high temperature synthesis. Meanwhile,
electrochemical performances were found to be controlled by both impurity
and crystallite size. We believe that with more understanding of synthesis
parameters, LMO single crystals could achieve optimal electrochemical
performance