Controllable growth of LiMn2O4 by carbohydrate-assisted combustion synthesis for high performance Li-ion batteries
Wei Huang, Gang Wang, Chong Luo, Yaobin Xu,Ying Xu, Brian J.Eckstein, Yao Chen, Binghao Wang, Jiaxing Huang, Yijin Kang, Jinsong Wu, Vinayak P.Dravid, Antonio Facchetti, Tobin J. Marks
LiMn2O4 (LMO) spinels with diverse achievable morphologies are realized using solution processing techniques including sol-gel and cofuel-assisted combustion synthesis (CS). These LMOs are utilized as cathode materials in lithium ion batteries (LiBs), with LMO produced here by low-temperature, sorbitol-assisted combustion synthesis (SA-CS) yielding superior performance metrics. Morphological analysis by combined X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy demonstrates that these SA-CS LMO powders have optimum LiB grain (<500 nm) and crystallite (~30 nm) dimensions as well as spinel phase purity. Cathode mixtures having micron-scale, uniformly distributed LMO, conductive carbon, and a polymer binder provide effective electron and Li transport as assessed by electrochemical impedance spectroscopy and fabricated battery performance, showing high capacity (~120 mA h/g), good cycling stability (~95% capacity retention after 100 charge/discharge cycles), and high charge/discharge rates (up to 86 mA h/g at 10 C). SA-CS provides a simple, efficient, lower temperature, and scalable process for producing morphology-controlled high-performance LiB cathode oxides.