High Voltage (4 V ) Electrochemical (Ultra) Capacitor for Satellite Energy Storage

Satellite mission life is limited by the life of its batteries which are significantly limited by the amount of pulsing, peak loads or spikes which occur during discharge cycles. A capacitor is coupled with the battery in order to reduce or eliminate these damaging current demands and thereby prolonging the lifetime of the battery and the satellite mission. The electrochemical capacitor (EC) is the type of capacitor of choice for this weight critical application which requires the maximum energy storage capability (energy density) which is currently at 5.7 Wh/kg. LithChem has developed a series of new EC non-acetonitrile electrolytes which have shown twice the energy density (>11 Wh/kg) by operating at higher voltage (>3.4 V) and at a higher ion concentration than the best ECs available. LithChem proposes to maximize the performance of this new EC by optimizing the following: electrode material including carbon nano tubes; operating voltage (3.4-4.0 V); molarity; and capacitor cell configuration. It appears that an energy density of >15 Wh/kg may be achievable with a corresponding power density of > 12 KW/KG. This new electrochemical capacitor (EC) could reduce the size, weight and cost of the current EC by more than 50%.