Li–S batteries are experiencing a large increase in their research lately. The main reason for this efforts is their high energy density and specific capacity. Sulphur is also very abundant and thus enables a reduced cost for usage in batteries. In Li–S batteries with eter based electrolytes we can easily discover the polysulphide shuttle effect which represents the biggest problem in such systems. It can be smoothly avoided with the use of ultramicroporous carbons with pore size less than 0,7 nm. If we use such composites, we can disable the contact between our electrolyte and active sulphur material within the pores of the carbon composite. This actually means we can also use carbonate based electrolytes which are meant to be useless in combination with bigger pore sizes. With the design of a cathode electrolyte interphase at the surface of the pores, we can further decrease the contact and therefore the loss of active sulphur due to the polysulphide shuttle effect. We can perform the optimization through different parameters. The most common ones are: changing of electrode thickness, use of different electrolytes and use of different voltage cutoffs. We can conclude that through this optimization process we can create a stable and effective battery for longer cycling.
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