Synthesis of three-dimensionally interconnected sulfur-rich polymers for cathode materials of high-rate lithium–sulfur batteries

Abstract

Elemental sulfur is one of the most attractive cathode active materials in lithium batteries because of its high theoretical specific capacity. Despite the positive aspect, lithium–sulfur batteries have suffered from severe capacity fading and limited rate capability. Here we report facile large-scale synthesis of a class of organosulfur compounds that could open a new chapter in designing cathode materials to advance lithium–sulfur battery technologies. Porous trithiocyanuric acid crystals are synthesized for use as a soft template, where the ring-opening polymerization of elemental sulfur takes place along the thiol surfaces to create three-dimensionally interconnected sulfur-rich phases. Our lithium–sulfur cells display discharge capacity of 945 mAh g−1 after 100 cycles at 0.2 C with high-capacity retention of 92%, as well as lifetimes of 450 cycles. Particularly, the organized amine groups in the crystals increase Li+-ion transfer rate, affording a rate performance of 1210, mAh g−1 at 0.1 C and 730 mAh g−1 at 5 C.

Inverse Vulcanization of Sulfur using Natural Dienes as Sustainable Materials for Lithium–Sulfur Batteries

“…[17] Only recently has the inverse vulcanization methodb een extendedt ot he use of the more common divinylbenzene [18] cross-linkers or naturalm olecules. [17] Only recently has the inverse vulcanization methodb een extendedt ot he use of the more common divinylbenzene [18] cross-linkers or naturalm olecules.…”

Sulfur and Its Role In Modern Materials Science

“…[41] This approach is based on the development of organosulfur compounds from elemental sulfur.T hese compounds were synthesized using "soft templates" made up of trithiocyanuric acid (TTCA)c rystals.S ulfur was embedded into the porous TTCA templates during two vulcanization steps,a fter which cross-links were formed between the elemental sulfur and TTCA ( Figure 5). [41] This approach is based on the development of organosulfur compounds from elemental sulfur.T hese compounds were synthesized using "soft templates" made up of trithiocyanuric acid (TTCA)c rystals.S ulfur was embedded into the porous TTCA templates during two vulcanization steps,a fter which cross-links were formed between the elemental sulfur and TTCA ( Figure 5).…”

“…300 8 8C) so that thee lectrode materialsm aintain am oltens tate (Figure6). [41] thermalexpansion coefficientofthe sealant, whiledecreasing itsv iscosity.T hese components were meltedt ogether, then cooled andg roundi ntop owders.T he powdersw eres haped into cylindersa nd placed betweena lumina plates,h eated at 350 8 8Cf or 60 minutes, then rapidlyc ooledt or oomt emperature. have developedseveral glassceramic sealantmaterials.…”

Advances in Cathode Materials for High-Performance Lithium-Sulfur Batteries

“…Copyright 2015, American Chemical Society.(C) Schematic drawing describing the synthetic procedures of sulfur-rich polymers with controllable morphology.(D) The discharge/charge capacities and Coulombic efficiencies of Li/S-TTCA-I and Li/S-TTCA-II cells, compared with those of conventional Li/S-C cells. Reprinted with permission from (Kim et al., 2015). Copyright 2015, Nature Publishing Group.…”

“…reported a sulfur-containing polymer as an active cathode material to improve the electrochemical performance of LSBs by a new methodology (Kim et al., 2015). Organosulfur cathodes with different morphologies were synthesized by using porous organic crystal templates, which was a unique feature of their system (Figure 16C).…”