Washington: Your small electric car may soon become faster and more efficient thanks to `super capacitors` that are capable of storing far greater charge in a much smaller package.
The energy storing devices can be made from a material called calcium-copper-titanate (CCTO) which, the researchers - including Indian-origin lead author Raghvendra Pandey - have identified as a practical energy-storage material.
"Efficient, high-speed, high-density energy storage is important to many fields, and super capacitors offer this," said William Stapleton, an assistant professor of electrical engineering at the Texas State University (TSU).
"Fields such as `green` energy and electric vehicles could benefit immediately from the use of these materials," he added.
Pandey, professor of electrical engineering at TSU, and others showed that in CCTO, two properties of fundamental importance for the efficiency of a capacitor device are tightly linked.
The first property, called permittivity, is the physical property of the capacitor material that allows it to store energy - with higher permittivity values representing a better capacitor, said the study that appeared in the journal AIP Advances.
The second property, called loss tangent "has to do with how efficiently energy can be moved into and out of the capacitor, that is, how much is lost in the process to inefficiency", Stapleton said.
"When the loss tangent is high," explained Pandey, "the capacitor is `leaky` and it cannot hold a stored charge for more than a few seconds."
Pandey and his team have demonstrated that CCTO super capacitors should be capable of achieving high permittivity while maintaining low loss tangent, which would make them suitable for storing energy at the desired levels for many industrial applications.