Rickshaws in Bangladesh. Source: M. Tawsif Salam/CC BY-SA 3.0Researchers from the University of Warwick in the U.K. are proposing to reuse electric vehicle (EV) batteries to power the roughly one million rickshaws used to transport people in Bangladesh.

To reduce the carbon footprint of motorized rickshaws in Bangladesh, the research team from the University of Warwick is investigating the possible reuse of depleted lithium ion (li-ion) batteries once used to power electric vehicles, which are typically retired once they reach 70% to 80% of their so-called “state of health.” State of health, as the name suggests, is a measure of an EV battery’s health.

However, a li-ion battery at a 70% state of health still has, according to researchers, roughly three times higher energy density than a brand-new lead acid battery, which is currently what motorized rickshaws, otherwise known as easy-bikes, rely on for power. Because lead-acid batteries have lifetimes in the range of six to 12 months, using EV batteries as a substitute could potentially translate to three- to five-year lifetimes for motorized rickshaws.

As such, replacing lead-acid batteries with EV li-ion batteries could mean not only significant improvements in rickshaw operating lifetimes, but also a reduction in the number of batteries that need to be recycled and, consequently, an improved ecosystem.

The proposal to replace lead-acid batteries with EV li-ion batteries comes on the heels of a recent warning from experts that li-ion batteries meeting their maximum operating life for EVs are beginning to accumulate, with no specific plans for how to avoid adding to the current e-waste problem affecting much of the world.

This is not the first time researchers from the Warwick Manufacturing Group (WMG) at the University of Warwick have explored other avenues for reusing EV batteries at the end of their life. Recently, the WMG researchers explored using EV li-ion batteries as small energy storage systems to power regions off the grid in developing countries.