The efficient storage of electric energy is a bottleneck for all mobile electric applications. Battery usage is significantly limited by weight and costs per kWh storage capacity. Current lithium-ion batteries do not only limit the range of electric cars to no more than 150 km, they also make up the largest part of the total manufacturing costs. Accordingly, there is a pressing demand for novel storage systems with higher energy densities and lower costs.
Apart from lithium-air systems, which are still in a state of early basic research, there is now an increasing interest in lithium-sulfur batteries (Li-S). Here, specific energy densities of more than 600 Wh/kg are expected and in addition, the expensive cathode material of lithium-ion cells is substituted by sulfur, which is less expensive, non-toxic and available in virtually unlimited quantities. In previous developments for Li-S batteries lithium-metal anodes were applied, a material which is extensively responsible for low lifetime and safety risks.