Revealing Charge Transport Mechanisms in Li2S2 for Li-Sulfur Batteries. Academic Article uri icon


  • Besides lithium sulfide (Li2S), lithium persulfide (Li2S2) is another solid discharge product in lithium-sulfur (Li-S) batteries. Revealing the charge transport mechanism in the discharge products is important for developing an effective strategy to improve the performance of Li-S batteries. Li2S2 cannot transport free electrons due to its wide bandgap between the valence band maximum (VBM) and conduction band minimum (CBM). However, electron polarons (p-) and hole polarons (p+) can appear in solid Li2S2 due to the unique molecular orbital structure of the S22- anion. The thermodynamic and kinetic properties of native defects are investigated. It is found that negatively charged Li vacancies (VLi-) and p+ are the main native defects with a low formation energy of 0.77 eV. The predominant charge carrier is p+ because p+ has a high mobility. The electronic conductivity related to p+ diffusion is dependent on temperature, and high temperatures are preferred to increase the conductivity.

published proceedings

  • J Phys Chem Lett

author list (cited authors)

  • Liu, Z., Balbuena, P. B., & Mukherjee, P. P.

citation count

  • 49

complete list of authors

  • Liu, Zhixiao||Balbuena, Perla B||Mukherjee, Partha P

publication date

  • April 2017