For our customer’s convenience we are now selling super capacitors to be used with our products.  The Panasonic EEC-S5R5V105N capacitor is a through hole electrolytic capacitor that works well with our energy harvesting products.  The part is easily mounted on the RFD-ASSY-01 energy harvesting system board or the RFD102A-TB.  Users may also clip to the leads be able to test their harvesting system with and without storage.  Please note that the charging time depends upon the input power and the conversion efficiency of the energy harvesting module which varies with the load presented to the DC output pins.  We have seen it take 20mins to charge up to 2.5V at 13dBm input power at 915MHz. Charging is very slow! The Super Capacitor has a 5.5V max voltage rating and should be protected with a Zener diode or other device that limits the voltage from reaching this limit. The datasheet can be found here: http://industrial.panasonic.com/cdbs/www-data/pdf/RDG0000/ABC0000C25.pdf