Lithium-sulfur batteries could deliver higher energy storage capacities than the common lithium-ion batteries. Aramugam Manthiram, Texas Materials Institute, Austin, Texas, and co-workers used carbonized cotton to prepare a lithium-sulfur battery with high performance. The carbon material was obtained by simply carbonizing cotton pads under an inert atmosphere. The carbonized cotton has a hierarchical macro/microporous structure with a high surface area that allows a record sulfur loading of 61.4 mg cm^–2 (80 wt%) in the cathode.

The team then assembled button cells with their new cathode material. They found a capacity retention of 70 % after 100 cycles and low self-discharge effects after 60 days of storage. According to the researchers, the good electrochemical performance is the result of both the complex macropore structure and the high accessible reaction area in the micropores. Furthermore, the excellent mechanical properties of the material are believed to accommodate the drastic volume changes during cycling.

• A Carbon-Cotton Cathode with Ultrahigh-Loading Capability for Statically and Dynamically Stable Lithium–Sulfur Batteries,
  Sheng-Heng Chung, Chi-Hao Chang, Arumugam Manthiram,
  ACS Nano 2016.
  DOI: 10.1021/acsnano.6b06369