Duplex trapping and charge transfer with polysulfides by a diketopyrrolopyrrole-based organic framework for high-performance lithium–sulfur batteries

Abstract

The duplex trapping behavior between a DPP-based POF and polysulfides is propitious for maintaining active substances and restricting the shuttle effect, realizing Li–S batteries with high rate, high sulfur content and high capacity retention.

Infixing NiS2 nanospheres into a three‐dimensional rGO/CNTs‐Li carbon composite as superior electrocatalyst for high‐performance Li−S batteries

“…The elemental mapping analysis of NiS 2 @rGO/CNTs‐Li in Figure g manifests the coexistence of Ni, S, C and O elements. As shown in Figure S2, the compact coating layer of NiS 2 @rGO/CNTs‐Li (6.52 μm) covers the large pores of the pristine separator and forms a stable physical barrier, which could potentially withhold more electrolyte to improve battery kinetics …”

“…The adsorption ability towards polysulfide (Li 2 S 6 ) was visualized by adding the rGO/CNTs‐Li and NiS 2 @rGO/CNTs‐Li composites into the Li 2 S 6 solution, respectively . As shown in Figure d, the Li 2 S 6 solution containing NiS 2 @rGO/CNTs‐Li faded to near colorless from the initial orange color after 12 h static standing, while the control solution without the NiS 2 nanospheres showed inferior ability for adsorbing Li 2 S 6 .…”

“…As one of the most promising rechargeable battery systems, lithium‐sulfur batteries (LSBs) have attracted numerous attention owing to the overwhelming theoretical specific capacity (1675 mAh g −1 ) and energy density (2600 Wh kg −1 ) compared with the state‐of‐the‐art Li ion batteries, as well as low cost, environmental friendly and natural abundance of sulfur cathode . Notwithstanding their great advantages, the commercialization of LSBs has been strictly hindered by several critical obstacles, such as: (i) insulation nature of sulfur (5×10 −30 S cm −1 at 25 °C) and insolubility terminal products of Li 2 S 2 /Li 2 S resulting in underutilization of active substances and tardy redox kinetics; (ii) the huge volume expansion of cathode (∼79%) and severe lithium dendrites of anode which may bring about pulverization of electrode; (iii) the shuttle effect caused by the dissolved intermediates of LiPSs (Li 2 S n , 4≤n≤8) . Hence, enormous efforts have been devoted to solving the afore‐mentioned issues from various aspects in order to achieve superior performance of LSBs.…”

Mechanistic understanding of the role separators playing in advanced lithium‐sulfur batteries

“…Beside modified commercial separators, new types of separators have also been developed to block the polysulfide with the chemical trapping effect . Wang et al prepared a graphdiyne (GDY)/polyimide composite separator.…”

Multidimensional Integrated Chalcogenides Nanoarchitecture Achieves Highly Stable and Ultrafast Potassium‐Ion Storage

“…At present, the demand for cost‐effective, high capacity, long cycle life, and high rate capability energy storage technology is drastically increasing due to the rapid development of portable electronics, electric vehicles, and large‐scale smart grids . However, the widely used and most advanced lithium‐ion batteries (LIBs) is severely limited by the scarcity, uneven global distribution, and the rising cost of lithium resources as well as the safety issues caused by lithium dendrites .…”