Polymeric ionic liquid as binder: A promising strategy for enhancing LiS battery performance

• Published in: Journal of energy storage 2024-03, Vol.80, Article 110285
• Main Authors: Santiago, Alexander, Robles-Fernández, Adrián, Soria-Fernández, Asier, Lopez-Morales, Jorge L., Castillo, Julen, Fraile-Insagurbe, David, Casado, Nerea, Armand, Michel, Garcia-Suarez, Eduardo J., Carriazo, Daniel
• Format: Article
• Language: English
• Subjects: Batteries; Cathode development; Lithium-sulfur; Polymeric ionic liquid; Polysulfide regulation
• ISSN: 2352-152X; 2352-1538
• DOI: 10.1016/j.est.2023.110285

The development of the most promising next-generation LiS batteries with an improved cyclability is one of the greatest challenges nowadays. In this sense, here, a novel imidazolium-based polymeric ionic liquid (PVI10Cl) was successfully synthesized and integrated into a high-performing sulfur cathode. The lithium polysulfide trapping ability of PVI10Cl was confirmed, which helps to accelerate conversion kinetics. This synergetic effect leads to enhanced C-rate response, improving the discharge capacities and reducing the overpotentials even at 1C in comparison with conventional PVdF binder. These features also allow cells to be operated for 100 cycles with excellent capacity retention. All in one, while conventional binders are viewed only as a “glue” to hold the active material together, it has been shown that PVI10Cl binder has additional functions and plays an active role during LiS battery operation. [Display omitted] •Novel imidazolium-based PIL has been successfully integrated as a binder in high-loading cathodes in Li-S technology.•The PIL has a stronger interaction with polysulfides, trapping them in the cathode and accelerating conversion reaction.•The sequestration of LiPS reduces the 'Shuttle effect', increasing the cell life compared to the conventional binder (PVdF).•PIL as binder achieves a remarkably high retention capacity after 100 cycles, even at almost lean conditions.