Supercapacitors of high power and energy density

1. Electrolyte Electrode material Electrochemical “window” Ion size Pore structure Electrochemically active impurities Surface chemistry Institute for Sorption and Problems of Endoecology, National Academy of Science of Ukraine Low internal resistance, Rin - key advantage of SC devices in various applications Heat generation = ʃI2Rint (low heat generation implies simple design and safety) Supercapacitor Efficiency = RLoad/(RLoad + Rin) (high efficiency is important for KERS and many other applications) Power output ~ 1/ Rin (high power density allows to meet customer requirements with less mass) Working voltage Quick response (low RC-constant) (is important for grid frequency regulation) Capacitance Also MASS and COST reduction! Thus:relectrolyte~ 0.9 Yunasko-Ukraine Conductivity, Ion mobility Resistance Leakagecurrent Abstract As pure “physical” devices, which do not involve any chemical or electrochemical transformations, any charge or mass transfer through the electrode-electrolyte interface, SC’s must demonstrate much faster charge/discharge operations and longer cycle life than any “chemical” batteries. Given this, SC devices can provide the key to a number of efficient power solutions that are mainly related with various backup systems to compensate short-term voltage surges or drops or with load leveling the batteries in various combined power sources. Low internal resistance can be one of key advantages of SC’s over all other types of energy storage devices. in bulk solution : Deff= 10.1×10-10 m2/s Correlation of Fc+ diffusion coefficients in-pores with SC resistance Contributions to total resistance Charge accumulated by positive and negative electrodes CV curves: 3-electrode cell (A), SC prototype (B) electrolyte: 1.3M TEMA BF4 in acetonitrile; scan rate: 10 mV/s N. Stryzhakova, S. Zelinsky, and Y. Maletin nstryzhakova@yunasko.com A SC resistivity (in W.cm2) total~ 1.0 rAl-C~ 0.01 rC~ 0.07 B Though: relectrolytein bulk~ 0.2 “pore resistance”~ 0.7 Supercapacitors of high power and energy density YUNASKO carbon-carbon EDLC performance (rated voltage 2.7V) 16 V, 200 F ESR (dc) 1.0 mW mass 2.5 kg equipped with voltage balancing system and temperature sensor Financial support from NAS Ukraine-STCU Project # 5500 is very much acknowledged