Quantum mechanics

Power density

Adsorption

Voltage

Composite number

Engineering

Biology

Electrochemistry

Materials science

Cathode

Power (physics)

Botany

Carbon fibers

Chemical engineering

Husk

Activated carbon

Capacitor

Porosity

Physical chemistry

Supercapacitor

Physics

Organic chemistry

Composite material

Chemistry

Electrode

Anode

Current density

Electrical engineering

Electrochimica Acta

We report the fabrication of a high energy-power density Li-ion hybrid supercapacitor (Li-HSC) using rice husk derived activated porous carbon as cathode and insertion type Li4Ti5O12 (LTO) as anode. Nanoporous carbon chemically activated with KOH (RHDPC-KOH) and H3PO4 (RHDPC- H3PO4) exhibited high surface area and improved porosity characteristics. With optimized electrode mass loading, the fabricated Li-HSC exhibited excellent electrochemical properties with a maximum energy density of ∼57 Wh kg−1 and ∼37Wh kg−1 for LTO/RHDPC-KOH and LTO/RHDPC-H3PO4 configuration respectively. The obtained energy density of 45 Wh kg−1 for RHDPC-KOH −based Li-HSC, even at a high power density of ∼4.3 kW kg−1, is far superior to several porous carbon-based Li-ion capacitors reported. Furthermore, the device showed excellent cyclability with capacity retention of ∼92% of initial capacity even after 2000 cycles, at high current density of 2 Ag−1.

Li-ion capacitor based on activated rice husk derived porous carbon with improved electrochemical performance