Mandi: Researchers, Associate Professor Viswanath Balakrishnan and his research scholar Piyush Avasthi, at the Indian Institute of Technology (IIT), Mandi, have developed aligned carbon nanotube-based electrodes that could be used in high energy supercapacitors.

Supercapacitors can charge and discharge instantly and can ideally last across millions of charge-discharge cycles without performance degradation.

The research has been published in Advanced Materials Interfaces and ACS Applied Nanomaterials.

"A promising route to improving the performance of energy storage devices, especially in terms of cycling life and charging times, is to move away from batteries towards supercapacitors," Balakrishnan said. They also have a higher power density than batteries, he added.

Where they have fallen short is the area of energy density; supercapacitors have 40 times less ability to store energy than the lithium ion battery.

A supercapacitor essentially comprises two conducting electrodes immersed in an electrolyte, which are separated by electrically insulating layer to separate the charges, the researchers said in a statement.

While applying the current, potential difference develops between two electrodes and opposite charged ions physically absorb on the respective surfaces of electrodes. This charge storage mechanism is highly reversible, which makes supercapacitors to charge and discharge quickly.

The quest for a 'perfect' battery that can store large amount of energy and be charged rapidly and repeatedly has spurred considerable research the world-over. The lithium ion battery that now powers almost all consumer electronics devices, like mobile phones, laptops and even electric cars, has its own limitations, say researchers.

One of the disadvantages with these batteries is that charging takes a lot of time causing extended down-times of operation. Also, durability is another major concern.

Carbon is usually used as the electrode material but traditional carbon forms result in low energy density.