EV batteries get extra power from coal in new experiment

Coal resources can be used as carbon sources for making energy storage devices such as supercapacitors for electric vehicles, new study suggests

File image | Photo Credit: C. Venkatachalapathy

Coal can inject some extra life into chargeable batteries for electric vehicles (EV) without burning, a new study has found.

An advanced model of a hybridized battery management system (HBMS) using coal-based pouch cell supercapacitors and Li-ion batteries in an experiment by a team of scientists helped increase the maximum speed of e-rickshaws to 45 km per hour with an additional power gain of 433 watts.

The maximum speed of e-rickshaws across the Indian market is 35 km per hour.

The study titled ‘Fabrication of pouch cell supercapacitors using abundant coal feedstock and their hybridization with Li-ion battery for e-rickshaw application’ was published in the latest issue of the Netherlands-based Journal of Energy Storage.

The authors of the study are Binoy K. Saikia, Santhi Maria Benoy, Mousumi Bora, Dipankar Neog, Dhrubajyoti Bhattacharjya, Akhil Rajbongshi, and Prasenjit Saikia. They are associated with Council of Scientific and Industrial Research (CSIR)-North East Institute of Science and Technology in eastern Assam’s Jorhat.

“For the fabrication of coal-based pouch cell supercapacitor, we synthesized highly porous, high-surface-area activated carbon with good electrochemical performances from low-grade sub-bituminous coal feedstock,” the study paper read.

Sub-bituminous coal found in Assam is of a lower grade with low carbon and high sulphur content, making it underutilised in power plants.

“For test-bed evaluation using the HBMS, a pack of pouch cell supercapacitor with capacitance of 500F (Farad, unit of capacitance) was integrated with the commercial supercapacitors and applied in an e-rickshaw containing Li-ion battery,” the paper read.

Compared with the output of an e-rickshaw with standard batteries, the combination of supercapacitors with battery increased the speed of the experimental e-rickshaw by about 10 km per hour, apart from delivering more power.

The experiment has fuelled the possibility of Indian coal being used as an indigenous carbon source for making energy storage devices such as supercapacitors for EVs.

“Coal combustion in power plants is banned in many countries due to pollution or emission. So, alternatively, coal can be converted to carbon in India for batteries and supercapacitors and made useful for the EV industry, in which carbon is imported in bulk,” Dr. Binoy Saikia, lead author, told The Hindu.

Using coal as an energy booster in batteries without combustion can go a long way in battling the effects of climate change, he said.