Dual‐Functional Hosts for Polysulfides Conversion and Lithium Plating/Stripping towards Lithium‐Sulfur Full Cells

Abstract

The practical application of lithium‐sulfur (Li−S) batteries is greatly hindered by the shuttle effect of dissolved polysulfides in the sulfur cathode and the severe dendritic growth in the lithium anode. Adopting one type of effective host with dual‐functions including both inhibiting polysulfide dissolution and regulating Li plating/stripping, is recently an emerging research highlight in Li−S battery. This review focuses on such dual‐functional hosts and systematically summarizes the recent research progress and application scenarios. Firstly, this review briefly describes the stubborn issues in Li−S battery operations and the sophisticated counter measurements over the challenges by dual‐functional behaviors. Then, the latest advances on dual‐functional hosts for both cathode and anode in Li−S full cells are catalogued as species, including metal chalcogenides, metal carbides, metal nitrides, heterostuctures, and the possible mechanisms during the process. Besides, we also outlined the theoretical calculation tools for the dual‐functional host based on the first principles. Finally, several sound perspectives are also rationally proposed for fundamental research and practical development as guidelines.

Regulating Polysulfide Transformation and Deposition Kinetics in Lithium–Sulfur Batteries Based on 3D Conductive Framework

“…On the other hand, the N doping of materials can also effectively adjust their localized electronic environment and immobilize polysulfides by forming strong bonds . FeN x -NPC exhibits the weakest UV absorption; it can be attributed that FeN x -NPC not only provides a rich pore size structure to meet the needs of the physical limitations but also serves as a “bifunctional affinity host” (lithiophilicity and sulfiphilicity) , between the Fe–N x active site and polysulfides . The possible mechanism of the action of FeN x -NPC and polysulfides is further explored through the XPS spectrum.…”

Functional Laminated Fiber Scaffold Based on Titanium Monoxide for Lithium Metal‐Based Batteries

“…So far, the PVDF/TiO@C fiber scaffold can meet the basic requirement for fabricating highefficiency cathode hosts for Li-S batteries. [51] By pairing the S/PVDF/TiO@C fiber cathode (S mass loading of 2 mg cm −2 ) with Li/PVDF/TiO@C fiber anode (Li deposition of 5 mAh cm −2 ), the feasibility of PVDF/TiO@C fiber scaffold for Li-S full battery is further studied, as illustrated in Figure 5d. [52] By contrast, the full battery configurations of S/TiO@C fiber || Li/TiO@C fiber and S/PVDF/C fiber || Li/PVDF/C fiber are also assembled in the same way.…”

“…So far, the PVDF/TiO@C fiber scaffold can meet the basic requirement for fabricating high‐efficiency cathode hosts for Li–S batteries. [ 51 ]…”

3D interconnected N-doped graphene architecture encapsulated with oxygen-deficient TiO2 nanotube array: synergism of oxygen vacancy and carbon materials on enhanced sulfur conversion and catalytic activity of TiO2 nanotube array in Li–S batteries

“…19 The notorious “shuttle effect” problem haunting Li–S batteries is a significant factor leading to the rapid decline in battery capacity. 20 This issue stems from the corrosive interaction between polysulfides and lithium metal on the anode. 21 Addressing this challenge is crucial for improving the longevity and efficiency of these batteries.…”