writer：Jin Zhang, Jin Wang, Zhi-qiang Shi*, Zhiwei Xu
keywords：Lithium ion capacitor， Low temperature， Activated carbon，Hard carbon;，Pre-lithiation
source：期刊
specific source：Journal of Electroanalytical Chemistry.
Issue time：2018年
Lithium-ion capacitor (LIC) is a novel electrochemical energy storage device that bridges the performance gap between the electrical double-layer capacitor and lithium ion battery. In this work, we fabricated lithium-ion capacitors (LICs) with activated carbon (AC) positive electrode and pre-lithiated hard carbon (HC) negative electrode. The effect of low temperature on the electrochemical performance of LIC is investigated by the galvanostatic charging-discharging, electrochemical impedance tests, rate performance and cycle performance testing. The electrolyte viscosity increases, the ionic conductivity decreases and ionic migration becomes slow in the charge-discharge process with the decrease of temperature, causing the increase ofresistance and the electrochemical polarization, which is responsible for the attenuation of LIC electrochemical performance. LIC at the temperature of - 20 degrees C exhibits the optimal low temperature electrochemical performance, high energy density up to 76.6 Wh kg(-1) and power density as high as 5.8 kW kg(-1) (based on active material mass of two electrodes), excellent capacity retention of 80.1% after 5000 cycles.