Figure 7. TEM and elemental analyses of S-HMT@CNTs cathode cycled 100 times and then a-c) charged to 2.8 V and d-f) discharged to 1.9 V. g-j) SEM and EDX-elemental analyses of DF-PCW interlayer recovered from S-HMT@CNT cell cycled 100 times at 1C rate between 1.9 and 2.8 V.

A rechargeable potassium–sulfur battery based on SPAN cathode and PAA binder demonstrated high reversible capacity and excellent cycling stability.

This study summarizes nanostructured metal phosphide-based materials for battery and supercapacitor applications and the recent progress, and provides the challenges and future research trends of nanostructured metal phosphide-based materials in electrochemical energy storage applications.

Based on the reversible conversion reactions, K 2 S x (5 ≤ x ≤ 6) ⎯

Sulfurized carbonized polyacrylonitrile (S-CPAN) is a promising cathode material for Li-S batteries owing to the absence of polysulfide dissolution phenomena in the electrolyte solutions and thus the lack of a detrimental shuttle mechanism. However, challenges remain in achieving high performance at practical loading because of large volume expansion of S-CPAN electrodes and lithium anode degradation at high current densities. To mitigate this problem, we propose a novel cell design including poly(acrylic acid) (PAA) binder for improved integrity of the composite electrodes and fluoroethylene carbonate (FEC) as additive in the electrolyte solutions for stabilizing the lithium metal surface. As a result, these cells delivered high initial discharge capacity of 1500 mAh g and a superior cycling stability ∼98.5% capacity retention after 100 cycles, 0.5 C rate, and high sulfur loading of 3.0 mg cm. Scaled-up 260 mAh pouch cells are working very well, highlighting the practical importance of this work.