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Download fileHigh Performance LiMn2O4 Cathode Materials Grown with Epitaxial Layered Nanostructure for Li-Ion Batteries
journal contribution
posted on 2014-02-12, 00:00 authored by Min-Joon Lee, Sanghan Lee, Pilgun Oh, Youngsik Kim, Jaephil ChoTremendous research works have been
done to develop better cathode
materials for a large scale battery to be used for electric vehicles
(EVs). Spinel LiMn2O4 has been considered as
the most promising cathode among the many candidates due to its advantages
of high thermal stability, low cost, abundance, and environmental
affinity. However, it still suffers from the surface dissolution of
manganese in the electrolyte at elevated temperature, especially above
60 °C, which leads to a severe capacity fading. To overcome this
barrier, we here report an imaginative material design; a novel heterostructure
LiMn2O4 with epitaxially grown layered (R3̅m) surface phase. No defect was
observed at the interface between the host spinel and layered surface
phase, which provides an efficient path for the ionic and electronic
mobility. In addition, the layered surface phase protects the host
spinel from being directly exposed to the highly active electrolyte
at 60 °C. The unique characteristics of the heterostructure LiMn2O4 phase exhibited a discharge capacity of 123
mAh g–1 and retained 85% of its initial capacity
at the elevated temperature (60 °C) after 100 cycles.