Madder root (Rubia sp.) Produces a Dye Powder, Purpurin, to Make a Green Battery (image) City College of New York Share Print E-Mail Caption More than 3,500 years ago, civilizations in Asia and the Middle East first boiled madder roots to color fabrics in vivid oranges, reds and pinks. In its latest technological incarnation, the climbing herb could lay the foundation for an eco-friendly alternative to traditional lithium-ion (Li-ion) batteries. Chemists from the City College of New York teamed with researchers from Rice University and the US Army Research Laboratory to develop a non-toxic and sustainable lithium-ion battery powered by purpurin, a dye extracted from the roots of the madder plant (Rubia species). Credit John/Vijai Usage Restrictions With credit. Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.