Lithium-ion batteries are typically made with conductive carbon electrodes, but with the use of silicon instead of carbon their capacity could be dramatically increased. The stumbling block has been that silicon-based electrodes tend to degrade quickly. But that has now been overcome thanks to an unlikely source – brown algae, which include giant kelp.

Igor Kovalenko of the Georgia Institute of Technology and colleagues have shown that electrodes made from silicon nanopowder and alginate – a natural polysaccharide obtained from brown algae – makes for a stable battery that has eight times the capacity of state-of-the-art graphitic electrodes. Alginate also has the advantage of being cheaper and more environmentally friendly than the plastics used instead in current technologies. The increased lifetime is a really remarkable improvement that would will undoubtedly by welcomed by anyone with a laptop computer.