All-Solid-State Supercapacitors Based on a Carbon-Filled Porous/Dense/Porous Layered Ceramic Electrolyte

Solid-state storage devices based on ceramic electrolytes have great potential because of their high security, long cycle life, and wide working temperature. In the present work, the three-dimensional structure of a carbon-filled porous/dense/porous layered ceramic electrolyte is designed for a solid-state supercapacitor. A single phase of Li 1.3 Al 0.3 Ti 1.7 P 3 O 12 (LATP) is obtained by a one-step solid-state reaction using ammonium polyphosphate (APP) as a PO 4 precursor. The densification of the LATP ceramic is improved by introducing sintering aids of LiMnPO 4 (LMP). Porous/dense/porous layered ceramics were then fabricated by sintering the LATP/LATP-2%LMP/LATP pellet at 825°C. Carbon-filled layered ceramics show a large capacitance of 0.13 F cm −1 at a low scan rate of 2 mV s −1 . The large capacitance for carbon-filled layered ceramics is due to the enhanced contact area between the electrode and solid electrolyte in the porous structure. The present supercapacitor also shows good cycling stability (∼91% of the initial capacitance after 600 cycles at a scan rate of 5 mV s −1 ).