A critical challenge for Li-ion battery electrodes is to provide high energy density, power density, and excellent cycle-life combined with safety and sustainability. Increasing conductive additive concentration in composite electrodes enables relatively higher power density but compromises energy density. The energy density increment can be attained by fabricating additive-free electrodes, maximizing active mass, while improving the charge transport to maintain high power density is significantly important especially for materials that have inherent conductivity issues (such as Li4Ti5O12). Herein, we demonstrate a nanostructured spinel lithium titanate (LTO) anode which is inherently safe and benign, deposited without additives through a green and scalable electrophoretic deposition (EPD) technique. The electrode is capable of rendering high capacity (160 mA h/g), high rate capability (72C), and excellent cycle-life (10 000 cycles). The outstanding performance in terms of cycle-life, energy, and power is attributed to the formation of electrically interconnected LTO nanoparticle films with porosity enabling better electrolyte percolation and rapid charge transfer. The porous nature of the film is visualized utilizing confocal fluorescence microscopy imaging which confirms the dye impregnation into the bulk of the films as well. The benefit of EPD is due to its potential for sustainability, scalability, rapid deposition rate, simple apparatus, and formation of porous film.
B. Gangaja, Muralidharan, H. P., Shantikumar V Nair, and Dr. Dhamodaran Santhanagopalan, “Ultralong (10K) Cycle-Life and High-Power Li-Ion Storage in Li4Ti5O12 Films Developed via Sustainable Electrophoretic Deposition Process”, ACS Sustainable Chemistry & Engineering, vol. 6, pp. 4705-4710, 2018.