Ultracapacitors: The Arch Nemesis of the Old Fashioned Battery: Battery Technology: Eco20/20

Ultracapacitors: The Arch Nemesis of the Old Fashioned Battery

The ultracapacitor may be the answer to a world that wants smaller, lighter and faster wireless chargers and portable devices. We want more options and features, but we do not want to increase the size or the bulk of the device we are putting them into.

Batteries, regardless of their type have limitations, including long charge times and expense and many of them are made of hazardous, toxic chemicals. While the theory and practice of the capacitor is nothing new, it has not been put into active or commercial use for a number of reasons. First, they come with a fairly high price tag and second, they have some issues with manufacturing. But, because they do have many of the key problems that the typical battery might (limited cycle life, an intolerance of temperature fluctuations and problematic charging rates to name a few), the capacitor is constantly on the back of scientific minds.

A capacitor might look like a typical battery at first glance, but it has many different features that set it apart. Batteries use differing chemicals to create its energetic charge while the capacitor uses a different concept: a solid electrode and electrolyte ions with opposite charge. The capacitor can create and hold an almost limitless amount of energy in a relatively small size. The capacitor can handle lower temperature extremes than a battery can and is not limited in the number of charge-discharge cycles that it can safely handle. The typical battery will fail at low temps and start degrading from the moment it leaves the factory. After being charged and discharged for so many cycles, a typical battery is dead and must be disposed of, leaving the question of how to safely and economically deal with spent batteries.

The exciting possibility of having capacitors that will one day power our laptop computers and our mobile phones depends on research into making them more viable for the size allowance. The electrode materials will have to be selected to give maximum power for minimum size and there will have to be a housing material that can hold both the electrode and electrolyte ions. Storage device materials that are reportedly being explored include coconut shells and coal.

Capacitors and super capacitors are being explored for larger scale applications as well. These could include use in hospitals as uninterruptible power supplies.