Electrochemical Performance of Lithium-Ion Capacitors Evaluated Under Thermal and High Voltage Stress with Various Electrolytes

Abstract

Research investigations into lithium-ion capacitors (LICs) for high power, moderate energy density Army applications have been evaluated under room temperature, high temperature, and high voltage conditions. The LICs were assembled as three-layered cells with an asymmetric configuration employing Faradaic pre-lithiated hard carbon anodes and non-Faradaic anion adsorption−desorption activated carbon (AC) cathodes. The LIC three-layered cells were tested for their rate capability at 1C to 10C discharge rates over the potential range of 2.2-3.8 V using various electrolytes and additives. The presence of electrolyte additives were found to be essential to the improved capacity performance and contribute to the prolonged cell cycling stability at room temperature, at high temperature, and at higher cut-off potentials.