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The main issues of lithium–sulfur (Li–S) batteries, including the insulating properties of electrode materials and the dissolution of lithium polysulfides into electrolytes, hinder their further development. Encapsulating S with a conductive agent is considered as an effective way to address these issues. The electrical conductivity of the electrode is substantially improved by the addition of a conductive agent. Furthermore, the polysulfide dissolution is also effectively suppressed by the physical/chemical confinement of the additives. An exploration of new encapsulation agents for the S cathode–hierarchical porous carbon derived from a peanut hull is reported. Such structures comprise the 3D interconnected network carbon and abundant meso/micropores, which significantly improve the electronic conductivity and effectively suppress the polysulfide dissolution. The high S loading, long lifespan, and great rate capability empower such a strategy to be an effective way to push the Li–S battery to further development. An exploration of a new encapsulation agent for S cathode is reported, hierarchical porous carbon (HPC) derived from peanut hull, which could significantly improve the electronic conductivity and effectively suppress the polysulfide dissolution. The high S loading, the long lifespan, and great rate capability empower such a strategy to be an effective way to push the Li–S batteries forward in development. [ABSTRACT FROM AUTHOR]

In virtue of high capacity and low manufacturing expense, transition metal carbonates (TMCs) have recently arisen enormous research interests as the anode materials for rechargeable lithium ion batteries (LIBs). However, the low electrical conductivity and unstable cycle performance impeded their further development. In this work, Co-B compounds are surface-engineered for the first time onto the mixed single-phase Mn 0.33 Co 0.67 CO 3 microspheres to accelerate the reaction kinetics and suppress the volume fluctuation of the electrodes during Li+ insertion/extraction. Specifically, Co-B nanoflakes not only function as the robust mechanical bridges between Mn 0.33 Co 0.67 CO 3 primary nanoparticles, but also provide extra pathways for electron/charge transport, both of which facilitate the improvement of electrochemical behaviors. Morever, the synergetic effect between Mn 0.33 Co 0.67 CO 3 and Co-B nanoflakes allow a high flux of Li+ across the interface to provide signifcantly boosted Li+ diffusivity. Impressively, the Mn 0.33 Co 0.67 CO 3 @Co-B electrode delivers a high reversible capacity of 806 mA h g−1 over 500 cycles at a high rate of 1.0 A g−1, demonstrating its superior cycling stability. Therefore, surface engineering of borides may be an effective and promising way to improve the electrochemical behaviors of conversion type anodes like TMCs. Image 1 [ABSTRACT FROM AUTHOR]

• Mn 3 (PO 4) 2 nanoflakes are firstly explored as the efficient polysulfide inhibitor in Li-S battery. • The Mn 3 (PO 4) 2 /rGO composites can effectively suppress the polysulfide shuttle. • The S@Mn 3 (PO 4) 2 /rGO composites show the enhanced electrochemical performances. The development of Lithium surfur batteries (LSBs) are beset with tenacious issues including the insulating property of the sulfur element and the dissolution of the reaction intermediate products into electrolyte, which result in low S utilization and poor battery cycling performances. In this work, we exploit metal phosphate as the S host for suppressing the sulfur dissolving and accelerating the polysulfide conversion, and firstly construct the S@Mn 3 (PO 4) 2 /rGO composites through an in-situ solution growth followed by S impregnation route. More importantly, the geometric compatibility of Mn 3 (PO 4) 2 nanoflakes and rGO nanosheet endows such S@Mn 3 (PO 4) 2 /rGO composites with high electrical conductivity and excellent mechanical durability. As evidenced by the electrochemical performances in LSB, the S@Mn 3 (PO 4) 2 /rGO cathode shows discharge capacities of 863 mA g−1 at 0.2 C after 100 cycles and 658 mAh g−1 after 470 cycles at 1.0 C with high Coulumbic efficiency of nearly 100%; more impressively, it delivers a high capacity of 407 mAh g−1 ever at 5.0 C rate during rate capability testing. Our research on the construction of S@Mn 3 (PO 4) 2 /rGO composites provides new insight and opportunitie to develop advanced LSBs with highly efficient inhibitors for trapping polysulfides and accelerating their conversion. [ABSTRACT FROM AUTHOR]