Two European researchers have discovered a way to turn waste from paper-making into a rechargeable battery cathode. The research could lead to cheaper, sustainable batteries made from a renewable source.
The waste in this case is lignin, a compound stripped from wood in the paper making process. During the paper-making process, wood is chopped up and cooked to break it down. Once the wood is done cooking, a substance called brown liquor is left behind, which is full of lignin. Grzegorz Milczarek from Poznan University of Technology in Poland and Olle Inganäs from Linköping University in Sweden combined lignin from brown liquor with a polymer (a large molecule chain) called polypyrrole to form a battery cathode.
Battery cathode are usually made of precious metals such as lithium, nickel, manganese, and cobalt, which aren’t renewable. Lignin, on the other hand, is the second-most-common polymer produced by living organisms in nature, and according to the researchers, it is much more renewable and is readily available from the paper industry.
Don’t expect this to make a huge difference in batteries just quite yet, as the batteries they created are limited and lose a charge when not in use. Still, this new research opens up development of this technology and the possibility that batteries with cathodes made from paper waste will be available to all of us in the future.