论文部分内容阅读
LiNi0.5Mn1.5O4-δ which possesses a high voltage of 4.7 V vs.Li+/Li and stable structure has been considered as a promising cathode material for high energy Li-ion batteries.In this study,well-crystallized LiNi0.5Mn1.5O4-δ nanorods with diameter of ～50 nm and length of ～500 nm were synthesized by a hydrothermal-solid state process followed by a lithiation reaction.It delivers ～120 mA h g-1 discharge capacity under 30 mA g-1 at 3.5-4.9 V,and 90 mA h g-1 at 150 mA g-1.An unstable solid electrolyte interphase (SEI) film with thickness 2 10 nm was observed by transmission electron microscopy.The thick and unstable SEI layers are responsible for its low rate performance and low coulombic efficiency during cycling.