A team of scientists has developed a low-cost supercapacitor device with excellent capacitive retention using a novel electrode material they synthesized which can pave the way for the next generation of high power-high energy storage devices.

The team comprises scientists from the International Advanced Research Center for Powder Metallurgy and New Materials (ARCI), an autonomous body of the Department of Science and Technology, in collaboration with the Indian Institute of Technology Hyderabad (IIT-H).

Supercapacitors have high-power density, long cycle life, and excellent capacity retention compared to their battery counterparts.

These devices developed from low-cost fabrication techniques are the need of the hour, considering their potential utility in the commercial market.

The team developed a facile, scalable, and cost-effective electrochemical route to synthesize electrodes made of Nickel Cobaltite (NiCo2O4) containing nanosheet structures incorporated with oxygen vacancies as an active material for hybrid supercapacitors.

These electrodes have excellent electrochemical performance.

Hybrid supercapacitors combine the features of both conventional double layer supercapacitors and batteries and act as high power-high energy storage devices.

However, it is challenging to design pseudo-capacitor devices with redox metal oxide (MO) materials with high porosity, high capacitance, and good cycle life. Cycle life refers to the number of charge and discharge cycles that a storage device can provide before it stops performing its functions.

Amending the intrinsic properties of the synthesized MO to enhance its conductivity, stability, and electrochemical activity was a challenge the team was able to overcome. It was successful in synthesizing NiCo2O4 nanostructured electrodes through a novel electrodeposition route.

The scientists also introduced an optimum number of oxygen vacancies by an environmentally benign chemical reduction process to make up for an active, positive electrode material for hybrid supercapacitor, as reported in their recent publication in the journal ‘Batteries & Supercaps.’

The discovery could be an effective alternative to the existing carbon-based electrodes for supercapacitors to achieve high energy density.

The research team also fabricated an asymmetric supercapacitor device using porous carbon and NiCo2O4 electrodes. The new supercapacitor exhibited excellent capacity retention and stability. The device could power devices like an LED lamp and a DC fan.

In April, scientists at the Institute of Nano Science and Technology had developed a new material for supercapacitors or pseudo-capacitors, which can store electrical energy by electron charge transfer. This material can be used as an alternative to batteries as it offers a low-cost, highly scalable energy storage solution.

In January this year, the Indian Institute of Science Education and Research and SPEL Technologies Pune had jointly developed a technology for generating functionalized graphene at lower costs.

This process will be used for the development of graphene-based supercapacitors for energy storage, according to the Department of Science and Technology. The supercapacitors will be fabricated at SPEL.