High ionic conductivity, low grain boundary impedance, and stable electrochemical property have become the focus for all-solid-state lithium-sulfur batteries (ASSLSB). One of the approaches is to promote the rapid diffusion of lithium ions by regulating the chemical bond interactions within the framework. The structure control of P 5+ substitution for Sn 4+ on lithium-ion transport was explored for a series of Li 3 PS 4 -Li 4 SnS 4 glass-ceramic electrolytes. Results showed that the grain boundary impedance of the glass electrolyte was reduced after heat treatments. The formation of LiSnPS microcrystals, a good superionic conductor, was detected by X-ray diffraction tests. Electrochemical experiments obtained the highest conductivity of 29.5 S cm −1 at 100 • C and stable electrochemical window from -0.1 to 5 V at 25 • C. In addition, the cell battery was assembled with prepared electrolyte, which is promoted as a candidate solid electrolyte material with improved performance for ASSLSB.

Co, N@CPDA-HCS exhibits better electrochemical performance due to the embedding of cobalt on the special structure as a host for sulfur.

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In this work, the authors proposed a unique strategy to prepare a high performance Lithium–Sulfur (Li–S) battery cathode by an N-rich nano-graphene hollow sphere from the Prussian blue analog Co3[Co(CN)6]2. The one-pot solution method with low cost materials was designed to synthesize the cathode by annealing with different temperatures and consistent HCl etching steps for the precursor. The Li–S batteries made by this precursor showed remarkable charge–discharge stability (570.4 mA h g−1 after 500 cycles at a 1 C current density) and outstanding rate performance (1145.5, 717.9, and 672.5 mA hg−1 at 0.1, 1.0, and 2.0 Ag−1 current densities) at 800 °C. The results indicated that the stable three-dimensional multi-layer hollow sphere structure relieved the volume expansion of sulfur, which had a significant impact on the polysulfide adsorption, inhibiting the “shuttle effect.” Also, the rich doping of nitrogen in this structure produced many defects and active sites that improved the interfacial adsorption of polysulfides. While Co3[Co(CN)6]2 shows its potential as a cathode material, the material design method used in this paper provides a unique approach to realizing a high performance sulfur cathode for Li–S batteries.