The EU-funded project LISSEN (Lithium sulfur superbattery exploitating nanotechnology) involved 14 companies, research institutes and universities. With the aim of developing advanced battery cells for electric vehicles, the consortium used 3D geometrical models to represent key material properties such as porosities. Researchers found that using modified organic solutions and stable ionic liquid electrolytes could significantly reduce environmental concerns related to sulfur cathode dissolution. Specifically, the ionic liquid electrolyte showed electrochemical stability even after the addition of long-chain polysulfides to limit cathode dissolution. Moreover, they found that removing Li metal from the anode could make batteries safer. However, researchers' efforts in LISSEN were directed towards the replacement of all battery components with metals that have higher performance in terms of energy density, reliability and safety. The newly developed battery configuration consists of a silicon-carbon composite anode and a nanostructured lithium sulfide-carbon composite cathode. In addition to a major increase in energy density, these materials support a comparatively longer life cycle at lower cost, the latter achieved by replacing cobalt with sulfur at the cathode. There was a lot of progress made during the three-year lifetime of the project on the small scale, optimising the battery electrolyte, and improving both anode and cathode materials. However, a lot of work still needs to be done on a larger scale to take the prototype developed in the laboratory to production. The Li-sulfur battery developed by LISSEN allows long-range driving on a single charge, promising to make electrical vehicles more practical and competitive. It is expected to be of use for both all-electric and plug-in hybrid vehicles. When ready for commercial use, its cost will be lower than that of conventional Li-ion batteries since the expensive cobalt-based cathode has been replaced by a low-cost material, sulfur.
Batteries, silicon, LISSEN, lithium sulfur, electric vehicles