High performance Li-ion battery-type hybrid supercapacitor devices using antimony based composite anode and Ketjen black carbon cathode

We report on antimony (Sb) and silicon (Si) based microstructured composite based lithiated anodes and their performance in battery-type hybrid supercapacitor devices. Ketjen-black carbon - 600 (or C-600) was used as capacitor-type cathode. For synthesis of materials, we employed a two-step process, viz., high probe sonication of the precursor materials followed by annealing at 700 °C for 1 h. The materials, namely, pure bulk Sb; Sb@C and Sb@Si/C were analyzed for phase, surface microstructure, and chemical states using X-ray diffraction (XRD), field emission scanning electron microscopy (FE SEM)/energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS), respectively. The as-synthesized alloy composites were pre-lithiated employing Li-ion battery (LIB) half-cell system via electrochemical pre-lithiation process in a fixed voltage range of 0.01–1.5 V for 8–10 charge-discharge cycles. Additionally, LISC devices, consisting of lithiated alloy-based anodes, and fresh C-600 carbon cathode, were successfully tested by electrochemical measurements, viz., Cyclic voltammetry (CV) electrochemical impedance spectroscopy (EIS) galvanostatic charge/discharge (GCD) techniques. The full-cell hybrid LISC devices were characterized at 1.5–4.0 V. The specific capacitances calculated for Sb//C-600, Sb@C//C-600, and Sb@Si/C//C-600 are 81.07 F/g, 153.96 F/g and 188.27 F/g, respectively, at a current density of 3 mA/g. The Sb@Si/C//C-600 LICS device delivered a maximum specific energy density of 163.42 Wh/kg, capacitive retention of 68.95 % for consecutive 10,000 cycles at 10 mA/g and an excellent cyclic stability conducive for the development of energy storage devices.