LLDev-1 Indoor Solar Development Kit
PowerFilm's hardware is currently configured to charge a Li-ion type battery
PowerFilm's LLDEV-1 hardware is currently configured to charge a Li-ion type battery with max voltage of 4.2 V and the output voltage is set to 3.0 V. The configuration can be customized by modifying SMD resistor dividers per the BQ25570 datasheet specifications. The LLDEV-1 is capable of running and operating with a capacitor as the storage element instead of the Li-ion battery.
The capacitor will maintain steady power to the system while light is available. Charge and discharge rate will be greatly affected by the size of the capacitor. If the capacitor is completely discharged (0 V) the charge rate will be slower because the harvester chip is not yet fully functional. Figures on the datasheet show charge times vs storage capacitance size for 0 V to 3 V and 3 V to 4.2 V. The capacitor must be rated for 6 V or greater.