Ancient plant dye used to make eco-friendly biomass batteries

Scientists in the United States have developed an environmentally friendly  biomass battery powered using a natural plant dye that was once highly coveted in the ancient world.

Science Daily reports
that chemists from the City College of New York in conjunction with researchers from Rice University and the US Army Research Laboratory have made a non-toxic lithium ion battery which generates power using purpurin, an extract from the roots of the madder plant (Rubia species) which was used in antiquity as a versatile dying agent.

Over several millenia ago civilizations in the ancient Near East and Asia made use of the plant extract as a dye to impart fabrics with colours such as orange, red and pink.

Modern scientists have discovered that the plant extract can also be employed as an electrode in biomass batteries, thus obviating the need to mine costly or environmentally harmful minerals such as cobalt.

According to Dr. Leela Reedy, a research scientist from Rice University who is a lead author on the project, the extraction and processing of cobalt is highly expensive, while the manufacture and recycling of standard lithium batteries entails the use of exorbitant amounts of energy.

Approximately 72 kilograms of carbon dioxide is pumped into the atmosphere for every kilowatt-hour of energy in lithium batteries which are manufactured or recycled.

Purpurin, which can be cultivated as a conventional crop, serves as an excellent organic electrode and its widespread usage could solve the problem of the disposal of used batteries.