Journal of Power Sources, Vol.401, 135-141, 2018
Li4Ti5O12/activated-carbon hybrid anodes prepared by in situ copolymerization and post-CO2 activation for high power Li-ion capacitors
Hybrid anodes with Li4Ti5O12 nanoparticles uniformly embedding in a mesoporous activated carbon matrix are prepared by CO2 activation of copolymerized resorcinol and hexamethylenetetramine loaded by lithium acetate and tetrabutyl titanate. The Li4Ti5O12/activated-carbon hybrid anodes show increased capacity retention as the activated carbon content in the composite increases, although their overall specific capacity decreases gradually. The hybrid anode with an activated-carbon content of 54 wt% exhibits the highest capacity retention of 67% at 4 A g(-1) referencing to that at 0.1 A g(-1) a. When coupling it with commercial AC cathode, the Li-ion capacitor displays an outstanding high energy density of 38 Wh kg(-1) even at a high power density of 7964 W kg(-1). Moreover, an energy density retention of 90.8% after 2000 cycles at 1 A g(-1) is preserved, demonstrating its very stable cycle performance. The results reported in this work indicate that the Li4Ti5O12/activated-carbon hybrids prepared by the proposed copolymerization and post-activation process may be very promising anode materials of Li-ion capacitors designed for high power applications.