Batteries vs. Supercapacitor

Energy storage is an essential component of renewable energy systems and micro-grids. The main objective is to investigate which is the more suitable type of short term storage to be included in the MGS; batteries or super-capacitors. To evaluate electrical energy storage in batteries and compare it with advanced super-capacitor technology, an experimental set up is designed and constructed. A set of experiments were conducted to investigate the different characteristics and their suitability to charging and discharging conditions. The results showed that super capacitor has higher power density than battery, while battery surpasses the super capacitor in energy density. Hence, the results confirm the understanding that super-capacitor is more suitable for rapid charging and discharging processes than battery which is more suitable for long charging and discharging times. Also, from the economic point of view battery is still more economical than super capacitors. The results are expressed mainly in terms of specific power efficiency and charge/discharge efficiency; they show that, batteries very useful for high energy density application.