Aqueous Supramolecular Binder for a Lithium–Sulfur Battery with Flame-Retardant Property

Abstract

A lithium−sulfur (Li−S) battery based on multielectron chemical reactions is considered as a next-generation energy-storage device because of its ultrahigh energy density. However, practical application of a Li−S battery is limited by the large volume changes, insufficient ion conductivity, and undesired shuttle effect of its sulfur cathode. To address these issues, an aqueous supramolecular binder with multifunctions is developed by cross-linking sericin protein (SP) and phytic acid (PA). The combination of SP and PA allows one to control the volume change of the sulfur cathode, benefit soluble polysulfides absorbing, and facilitate transportation of Li + . Attributed to the above merits, a Li−S battery with the SP− PA binder exhibits a remarkable cycle performance improvement of 200% and 120% after 100 cycles at 0.2 C compared with Li−S batteries with PVDF and SP binders. In particular, the SP−PA binder in the electrode displays admirable flameretardant performance due to formation of an isolating layer and the release of radicals.

Development of Proteins for High‐Performance Energy Storage Devices: Opportunities, Challenges, and Strategies

“…To further integrate more functions of protein-based binders, Qui et al reported an aqueous supramolecular binder combining PA and crosslinked SP for Li-S batteries with excellent flame retardant properties to improve the safety of high-energy batteries. [104,108,109] The combination of PA and SP allows the binder to trap lithium polysulfides via electrostatic interactions, alleviating the volume change of the sulfur cathode during lithiation and delithiation processes, and providing excellent flame Figure 11. a) SEM images of the "SGA" electrodes and "SPA" electrodes before cycling and after cycling.…”

“…f) Flame-retardance SPI tests of sulfur cathodes with PVDF and SP-PA binders. Reproduced with permission [104]. Copyright 2021, American Chemical Society.…”

Cross-Linked γ-Polyglutamic Acid as an Aqueous SiOx Anode Binder for Long-Term Lithium-Ion Batteries

“…Li + conductivity is also the essential factor that the binders should have. 33,34 The SiO x anode material is intrinsically Li +insulating. The employment of binders with high Li + conduction is vital to the transport of Li + through the surface of the SiO x active materials.…”

“…The robust mechanical strength and high elastic functions of the binders keep the particles in contact and alleviate the volume change of SiO x in the cycled process. Li + conductivity is also the essential factor that the binders should have. , The SiO x anode material is intrinsically Li + -insulating. The employment of binders with high Li + conduction is vital to the transport of Li + through the surface of the SiO x active materials.…”

Superior polysulfide adsorption ability by using Ti3C2 nanosheets as effective reservoirs for high electrochemical performance

“…Much effort has been devoted to the study of lithium-sulfur batteries because of their high energy density, long cycle life, and low cost; this technology could be applied in many areas, such as electric vehicles and other electric applications. [1][2][3][4][5] However, the low utilization of their active materials greatly inhibits the commercial application of lithium-sulfur batteries. This is due to their poor electronic conductivity, their polysulfide dissolution, and the shuttle effect that takes place during the electrochemical cycles.…”