An electrical battery is a combination of one or more electrochemical cells, used to convert stored chemical energy into electrical energy. Since the invention of the first Voltaic pile in 1800 by Alessandro Volta, the battery has become a common power source for many household and industrial applications. There are two types of batteries: primary batteries (disposable batteries), which are designed to be used once and discarded when they are exhausted, and secondary batteries (rechargeable batteries), which are designed to be recharged and used multiple times. Batteries are charged when they undergo an internal chemical reaction. They deliver the absorbed energy, or discharge, when they reverse the chemical reaction.

An Ultracapacitor is an electric double layer capacitor (EDLC) that has an unusually high energy density when compared to common capacitors, typically on the order of thousands of times greater than a high capacity electrolytic capacitor. Ultracapacitors offer a unique combination of high power and high energy. Ultracapacitors are capable of very fast charges and discharges, and are able to go through a large number of cycles without degradation.

In power electronics applications, the batteries have been used for more than hundred years and Ultracapacitors are new in electronics market. The biggerchallenge for ultracapacitors is from traditional batteries such as the lead acid, lithium ion, nickel cadmium (NiCD), nickel metal hydride (NiMH) and others which existed in the market for more than hundred years. Below are the feature comparison between traditional batteries and the revolutionary ultracapacitors.

Charge Cycles

While batteries last for a limited number of charges and discharges, ultracapacitors can be charged and discharged for hundreds of thousands of cycles without performance loss.

Charging Time

Ultracapacitors have a very fast charging rate compared to batteries, which take more time to charge because of the chemical reaction involved.

Size and Weight

Ultracapacitors will be smaller and lighter than regular batteries.

Energy Density

Typically ultracapacitors hold one fifth to one tenth the energy of an electrochemical battery. This will likely to change with the development of ultracapacitor technology. So batteries are good in this.

Energy Release

Ultracapacitors release stored energy very quickly, whereas batteries release energy slowly and take a longer time. This makes Ultracapacitors good candidates for powering regenerative braking systems, which can greatly improve fuel efficiency under stop-and-go, urban driving conditions.

Environment Safety

Ultracapacitors do not involve in any chemical actions, and do not release any hazardous substances that can damage the environment. Batteries operate on chemical reactions, which is harm to human health and environment.

Self Discharge Rate

Self discharge rate of ultracapacitors is much higher compared to the self discharge rate of batteries. So batteries are good in this.

Maintenance Cost

Ultracapacitors offer virtually maintenance free operation, whereas batteries need regular maintenance.


Ultracapacitors are more reliable compared to batteries, as they can operate at broader temperature ranges, and environmental conditions.


Batteries offer higher capacitance than ultracapacitors. Batteries can power longer in case of Uninterrupted Power Supply (UPS) systems.

Overcharge Protection

Batteries easily destroyed with overcharging, whereas ultracapacitors can resist overcharging.


Ultracapacitors are more efficient than batteries in energy storage and discharging.

As of today, the revolutionary ultracapacitors are not the alternative to traditional batteries, but they serve as replacement when batteries do not meet specific application needs. With the fast changing technology upgrades in ultracapacitor manufacturing, ultracapacitors will definitely replace batteries in all applications in the near future.

To know more about ultracapacitors, please read Everything About EDLC Ultracapacitors.