In search of going greener with battery technology, collaborating principle investigators Igor Luzinov and Gleb Yushin, of their respective Schools of Materials Science and Engineering at Clemson University and Georgia Tech, have identified a new polymer known as alginate that is capable of boosting battery capacity and performance. The material works as a more efficient binder of silicon or graphitic nanoparticles in the production of battery electrodes – cathodes and anodes. Furthermore, alginate, which is produced by and extracted from rapidly growing brown algae, offers a non-toxic and environmentally friendly alternative to current battery technologies. The findings are published in a recent report in Science.

Modern lithium-ion batteries are used in a variety of applications such as cell phones and electric cars. Commonly the electrodes of these batteries are made from silicon or graphite, each with their own set of advantages and disadvantages. Silicon, for instance, theoretically offers a tenfold improvement in battery capacity over graphite at the expense of stability. With alginate, however, the team of scientists and engineers demonstrated that incorporation of the new binding material to silicon anodes increased capacity eight times higher than state-of-the-art graphitic electrodes.

"Making less-expensive batteries that can store more energy and last longer with the help of alginate could provide a large and long-lasting impact on the community," said Gleb Yushin. "These batteries could contribute to building a more energy-efficient economy with extended-range electric cars, as well as cell phones and notebook computers that run longer on battery power — all with environmentally friendly manufacturing technologies."

Working with Igor Luzinov at Clemson University, the scientists looked at ways to improve binder materials in batteries. The binder is a critical component that suspends the silicon or graphite particles that actively interact with the electrolyte that provides battery power.

"We specifically looked at materials that had evolved in natural systems, such as aquatic plants which grow in saltwater with a high concentration of ions," said Luzinov, a professor in Clemson's School of Materials Science and Engineering. "Since electrodes in batteries are immersed in a liquid electrolyte, we felt that aquatic plants — in particular, plants growing in such an aggressive environment as saltwater — would be excellent candidates for natural binders."

Finding just the right material is an important step toward improving the performance of lithium-ion batteries, which are essential to a broad range of applications, from cars to cell phones. The popular and lightweight batteries work by transferring lithium ions between two electrodes — a cathode and an anode — through a liquid electrolyte. The more efficiently the lithium ions can enter the two electrodes during charge and discharge cycles, the larger the battery's capacity will be.

Read more from Clemson University’s official release.

Link to a Science podcast interview with co-investigator Gleb Yushin.