App note from Vishay about constant voltage (CV) pulse charging as the most cost-efficient solution to use on Hyrid capacitors. Link here (PDF)
Rechargeable energy storage solutions are of high interest because of their flexibility, low maintenance requirements, and reduced cost over their life-cycle.
For compact applications, classic electrolytic capacitors are environmentally friendly alternatives and available for a wide range of rated voltages. However, they soon reach their energy storage limit with output requirements exceeding a few 100 mWs.
Electric double-layer capacitors (EDLC) offer high power and energy density, as well as long working life, but are limited to low working voltages in the same range as batteries. Electronic systems require a compromise between these technologies, namely solutions that combine the advantages of classic batteries and double-layer capacitors without the limitations.