Are super farad capacitors useful for cars

Like virtually all electronic products, automotive systems make extensive use of capacitors. However, with the rising adoption of cars using alternative propulsion technologies where management of electrical current and circuits is becoming more important, the role of capacitors is expanding.

Both supercapacitors and batteries attract a great deal of research because of the imperative role they play in adopting sustainable energy solutions not just for vehicles, but in a broader context including storage for renewables, heavy machinery, portable tools and wearable devices.

While the construction of both is somewhat similar, the two devices have different physical mechanisms of operation. Batteries employ chemical reactions to create electrical energy, while supercapacitors store electrical energy by a mechanism called the electric double layer (EDL) effect.

This has been demonstrated in rail systems and busses Li et al., 2017, Technology, 2017. The Aowei development company in Shanghai, China have been supplying supercapacitors as the only power source for the Capabus public transport network since 2006.

Typically supercapacitors are used for their high specific power (W/kg). However, the specific energy of present commercial supercapacitors is lower than that of most batteries. Fig. 2 is a Ragone plot depicting the specific power vs specific energy for a range of different types of electric energy storage devices.

Batteries employ chemical reactions to create electrical energy, while supercapacitors store electrical energy by a mechanism called the electric double layer (EDL) effect. This article will explore the EDL operation of supercapacitor devices in further detail in Section 2, while comparing it to other classes of electrical storage devices.