(Left) Purpurin extracted from the center madder root is chemically lithiated (meaning treated with lithium of its compounds, shown right) This treated extract can make for an alternative to current lithium-ion battery cathodes. (via Rice University)
To combat the increasing amount of pollution and waste being produced every year, green technology has quickly grown into a large and important area of research. More specifically, green technology involves creating products that can meet the needs of society while not using up and depleting natural resources. Such products should be able to be fully re-used and recycled, reduce pollution and waste, and in some cases provide an alternative source for energy sources currently used, such as fossil fuels. Although lots of research and studies have been conducted on green technology, none have devoted a great deal of time to creating a more environment friendly battery.
Additionally, due to the rise of technical devices we use batteries have become an integral part of modern life. As a result, countless batteries are disposed of improperly around the world every day. These batteries can have an extremely harmful effect on the environment by releasing toxic substances and heavy metals into water, air, and the land. Even batteries that are recycled properly have to go through an extensive and expensive process. However, researchers from Rice University and the City College of New York may have made the first step toward creating a more effective and efficient green battery.
The researchers may have found a substance that can replace the cobalt cathodes used in lithium ion batteries. Their material used is called purpurin, a fully plant based substance which is derived from madder, a commonly found herb. The lead author on the study, Arava Leela Mohana Reddy, stated, “This is an area that needs immediate attention and sustained thrust, but you cannot discover sustainable technology over night. 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 researcher's prototype battery is created with the purpurin cathode which includes 20% of carbon for better conductivity. While testing the device, it was able to provide a capacity of 90 mAh per gram over 50 charge and discharge cycles.
While that capacity is still low, it is a start in a better direction for batteries. The researchers are going to continue to work on their prototype and want to find an organic material to replace the anodes also. Furthermore, they would like to find a better solution to use as an electrolyte until the entire battery is entirely organic. While the researchers are hard at work, we can remember to recycle all of our used batteries and when possible use rechargeable batteries or longer lasting ones to help the cause.