Thianthrene polymers as 4 V-class organic mediators for redox targeting reaction with LiMn₂O₄ in flow batteries.

ABSTRACT: Redox targeting reaction is an emerging idea for boosting the energy density of redox-flow batteries: mobile redox mediators transport electrical charges in the cells, whereas large-density electrode-active materials are fixed in tanks. This study reports 4 V-class organic polymer mediators using thianthrene derivatives as redox units. The higher potentials than conventional organic mediators (up to 3.8 V) enable charging LiMn₂O₄ as an inorganic cathode offering a large theoretical volumetric capacity of 500 Ah/L. Soluble or nanoparticle polymer design is beneficial for suppressing crossover reactions (ca. 3% after 300 h), simultaneously contributing to mediation reactions. The successful mediation cycles observed by repeated charging/discharging steps indicate the future capability of designing particle-based redox targeting systems with porous separators, benefiting from higher energy density and lower cost.

SUBMITTER: Hatakeyama-Sato K 

PROVIDER: S-EPMC10082199 | biostudies-literature | 2023 Apr

REPOSITORIES: biostudies-literature