Scientists from the United States and China have identified a polymer that makes high energy lithium sulphide batteries work for longer, while providing at least four times the energy available with current technology.
Lithium sulphur batteries are a very promising option for energy storage, offering several times as much energy as lithium ion batteries. However, they are currently limited by a short battery life due to the irregular dispersion of lithium in the electrode slurry and the loss of soluble polysulphides in the electrolyte.
Using initial numerical modelling and lab tests, researchers found that polyvinylpyrrolidone (PVP) acts as a strong, dual functional binder that holds a battery’s lithium sulphide and polysulphides during cycling. The PVP coating allows lithium ions to spread more smoothly throughout the cathode, preventing the formation of large particles and minimising the loss of polysulphides, resulting in extended battery life even after 500 cycles.
Z She et al, Chem. Sci., 2013