Quasi‐solid‐state conversion cathode materials for room‐temperature sodium–sulfur batteries

Abstract

Room-temperature sodium-sulfur batteries (NaSBs) are promising candidates for next-generation large-scale energy storage solutions. However, the wellknown polysulfide shuttling of soluble long-chain sulfur intermediates still remains a limitation in NaSBs, leading to rapid capacity loss arising from the dissolution of active sulfur into the electrolyte. This problem is effectively circumvented in quasi-solid-state conversion cathodes by elimination of the presence of these soluble intermediates altogether, with only insoluble intermediates formed in the process. Herein, we discuss various cathode materials that undergo quasi-solid-state conversion when cycled in a liquid electrolyte, including chemically bonded short-chain sulfur species, shortchain sulfur via physical confinement, and quasi-solid-state conversion cathodes with long-chain sulfur moieties. We conclude by highlighting the current challenges and possible strategies to improve the mechanistic understanding and cycling performance of NaSBs for practical applications.

High Pseudocapacitance‐Driven CoC2O4 Electrodes Exhibiting Superior Electrochemical Kinetics and Reversible Capacities for Lithium‐Ion and Lithium–Sulfur Batteries

“…The linear sweep voltammetry (LSV) curve further studied the catalytic activity of CoC 2 O 4 for the Li 2 S oxidation (Figure 7d). Compared with pure C electrode, CoC 2 O 4 electrode exhibits lower initial potential (‐0.29 V @ 1 mA cm −2 ) and higher current density, indicating that CoC 2 O 4 significantly accelerates the reversible transformation of Li 2 S. [ 73 ] The deposition behavior of Li 2 S on pure carbon and CoC 2 O 4 was studied by chronoamperometry at 2.05 V (Figure 7e,f). The accumulated capacity on pure carbon and C/ CoC 2 O 4 /S is 113.8 and 76.4 mAh g −1 , respectively.…”

“…As shown in Figure 7b, C/CoC 2 O 4 effectively adsorbs polysulfide compared with pure C sample, suggesting that there is a strong adsorption capacity between CoC 2 O 4 and lithium polysulfide. [72] As shown in Figure S8 electrode exhibits lower initial potential (−0.29 V@1 mA cm −2 ) and higher current density, indicating that CoC 2 O 4 significantly accelerates the reversible transformation of Li 2 S. [73] The deposition behavior of Li 2 S on pure carbon and CoC 2 O 4 was studied by chronoamperometry at 2.05 V (Figure 7e,f). The accumulated capacity on pure carbon and C/ CoC 2 O 4 /S is 113.8 and 76.4 mAh g −1 , respectively.…”

Recent advances in perovskite oxide electrocatalysts for Li–O2 batteries

“…1 The soaring demand for electrical energy storage and conversion systems has driven exploration into metal-ion batteries, metal-air batteries, and redox-flow batteries batteries. [2][3][4][5][6] Lithium-air batteries have a superior theoretical energy density of above 5000 Wh Kg −1 (Fig. 1), and a large theoretical open circuit voltage of 2.96 V ( Eq.…”

Uncovering the Binder Interactions with S-PAN and MXene for Room Temperature Na–S Batteries

“…18 Over the years, these issues have been confronted by various approaches, from the use of special sulfur composites to multifunctional additives. 19 One such approach is the use of sulfurized polyacrylonitrile (S-PAN), where the PAN backbone only allows sulfur to exist in the form of S 2 and S 3 . 20,21 By avoiding the presence of elemental S 8 , it greatly reduces the formation of long-chain polysulfides.…”