Abstract:

Lithium-sulfur batteries have received widespread attention due to their high theoretical energy density,abundant raw materials,and low cost.However, the low electrical conductivity and large volume expansion of sulfur cathode, and the shuttle effect of polysulfides in the process of de/intercalating lithium-ion hinder the commercial application of lithium-sulfur batteries.Combining the conductive materials as the sulfur carrier not only relieves volume expansion of sulfur cathode but also improves the conductivity of the positive electrode while restricting the shuttle of polysulfides to a certain extent.Hierarchical porous carbon is considered to be an ideal sulfur cathode carrier for its good conductivity,stable structure,controllable pore size,and morphology.Based on the development background of lithium-sulfur batteries,the research significance of hierarchical porous carbon as a sulfur carrier was explained.First,the preparation methods of hierarchical porous carbon materials such as hard template method,soft template method and activation method were introduced.The mechanism of micropores,mesopores and macropores in carbon materials in improving conductivity,stabi-lizing structure and inhibiting polysulfides shuttle effect in lithium-sulfur batteries was introduced.Finally, the prospects of hierarchical porous carbon was used as a sulfur carrier to promote the development of lithium-sulfur batteries were looked forward.

Key words: hierarchically porous carbon, lithium-sulfur batteries, sulfur cathode, shuttle effect, polysulfides