The dye the researchers are investigating for use in batteries comes from the roots of a climbing herb known as the madder plant.
Civilisations in Asia and the Middle East first boiled madder roots more than 3,500 years ago to extract purpurin, a nontoxic dye they used to colour fabrics vivid oranges, reds and pinks, TechNewsDaily reported.
"This is a paradigm shift. For the last 3,000 years, we've used purpurin as a dye material