Lithium sulphur batteries have the potential to exceed the gravimetric energy density of lithium-ion batteries by three or four times. However, this potential was not fully tapped until now.

In general, the functional principle of a lithium-sulphur battery is similar to that of a lithium-ion battery. Also here, lithium-ions are exchanged between the electrodes. However, the reaction mechanism of a lithium-sulphur battery is much more complicated than the mechanism of a lithium-ion battery. During charge and discharge intermediates are formed which are soluble in the electrolyte resulting in a lower capacity retention compared to lithium-ion batteries. Additionally, the high rate capability of lithium-sulphur batteries is significantly lower than the high rate capability of lithium-ion batteries. This phenomenon can be explained by the low ionic and electrical conductivity of the sulphur based cathode active materials.