There is one major component of renewable energy that is frequently overlooked. We talk a lot about wind, solar, and hydroelectric power, but then turn a blind eye to the fact that this electricity being generated is going into batteries that aren’t exactly sustainable. But now, ScienceBlog tells of a group of researchers at Rice University and the City College of New York who have found a way to replace the cobalt cathodes in lithium-ion batteries with cathodes made from purpurin, an entirely plant-based substance. Purpurin is known to have been used as a dye for textiles since 1500 BC, and it is derived from madder, a fairly common herb.
These new cathodes won’t increase the range of your electric car or improve your charging time, but they will make the battery more environmentally friendly, and that’s likely to be why you bought the car in the first place. As the lead researcher on the project, Arava Leela Mohana Reddy, put it “The current focus of the research community is still on conventional batteries, meeting challenges like improving capacity. While those issues are important, so are issues like sustainability and recyclability.” The materials used for batteries are not only non-renewable, but the process of turning them into batteries is also complicated and not very energy-efficient. This is another area where the purpurin batteries have an advantage, in terms of low environmental impact.
Reddy also said that the chemistry used for this was fairly simple, and that agricultural waste could potentially even be used for battery components. Recycling is another factor to consider with batteries, as it is still very difficult to do with lithium-ion types. But the more battery that is made from organic material and is renewable, the less of a concern this is. Reddy says that he is working to understand the relationships between the chemical components of batteries, and that through doing so he will be able replace conventional inorganic components with plant-based ones. Work has already begun on other battery components, and Reddy hopes to have a completely organic battery prototype up and running within the next few years.