Silicon oxide and its derivatives (SiO x , 0 < x < 2) are drawing significant interest as electrode material for Li-ion and Li–S batteries owing to their unique properties of high specific capacity, low working potential, high abundance, and environmental friendliness. In-depth research is done on the effects of electrolyte additives on the electrochemical and interfacial characteristics of SiO x -based anodes for Li–S batteries. Two different electrolyte additives namely lithium bis (fluorosulfonyl imide) (LiFSI) and lithium bis (oxalatoborate) (LiBOB) were incorporated in the supporting electrolyte containing 1 M lithium bis (trifluoromethanesulfonyl imide) (LiTFSI) in tetraethylene glycol dimethyl ether (TEGDME): 1,3 dioxolane (DOL) in the ratio of 1:1 (v/v). The Li/SiO x –Si–C 2032-type half-cells were assembled, and their charge–discharge properties were explored at 0.1 C-rate. Surface morphology and electrochemical impedance investigations of the electrode materials have been performed after cycling. The interfacial properties of SiO x -based electrodes were examined by FTIR and XPS. Among the electrolytes studied LiFSI-added electrolytes offer superior charge–discharge properties, which was attributed to the formation of a stable solid electrolyte interphase (SEI) layer on the electrode surface. The surface chemistry studies revealed the formation of Li 2 CO 3 and ROCO 2 Li peaks on the lithium metal surface. The formation of Li 2 CO 3 and ROCO 2 Li compounds are identified on lithium surface by XPS data and complemented by NMR analysis.

A novel Polyethylene oxide/lignocellulose (PEO/LIGC) coated dimpled electrospun P(VDF-TrFE) nanofibrous membranes were prepared and are employed as a separator for lithium-ion battery. ESEM images revealed the dimpled morphology of electrospun fibers and PEO/LIGC is located on the surface as well as in the space between the fibers. Results of tensile studies prove that PEO/LIGC coating improves the mechanical strength and elongation at break. The wettability of the membrane with liquid electrolyte was studied by contact angle analysis and the results indicate that both the membranes are readily wetted by the electrolyte. The electrolyte uptake of ecofriendly LIGC coated sample is similar to 440%, which is 647% higher than that of commercial Celgard separator. PEO/LIGC coated membrane shows similar to 86% porosity, which is 226% higher than that of the Celgard separator. Ionic conductivity studies show that dip coated P(VDF-TrFE) exhibits a conductivity 7. 04 x 10(-3) S cm(-1). A 2320 type coin cell (Li/Separator/LiFePO4) were fabricated using PEO/LIGC coated P(VDF-TrFE) and the fabricated cell is superior to that of a Celgard 2320 separator. Thus, the study reveals that the lignocellulose, a sustainable material helps to enhance the overall performance of the battery.

The Li-S battery commercialization has been hampered owing to challenging problems such as poor conductivity of elemental sulfur, volume change upon cycling, and shuttling of lithium polysulfide between the electrodes. To conquer these issues, a sensible electrode structure design is crucial. The incorporation of carbonaceous materials and metal oxides has been identified as an effective tool to foster the electrochemical properties of Li-S batteries. In this work, to confine polysulfide shuttling and to improve the conductivity of sulfur, MnFe2O4-seated rGO-sulfur composite was prepared and used as a cathode. The lithium-sulfur cell with MnFe2O4-seated rGO-sulfur composite cathode showed outstanding electrochemical performance delivering a discharge capacity of 1300 mAh g(-1) at 0.1 C-rate on its first cycle and a stable cycling was attained at 0.5 C-rate. In the composite cathode, each component functions for a specific reason: the rGO in the composite improves the conductivity of sulfur, while added- MnFe2O4 not only confines polysulfides appreciably but also provides integrity to the cathode as evidenced by SEM analysis. The self-discharge studies showed that the Li-S cell with MnFe2O4 was capable of retaining its charge even after 90 h which has overhead the earlier reports. The Li-S system with MnFe2O4 -laden cathode material exhibited better electrochemical properties than the un-laden one.

This review analyses the role of viologens, a unique class of redox-active molecules in various energy storage devices and the nature of chemical interactions in enhancing their overall performances.

Li–S batteries can replace the current LIBs due to its high specific capacity, low cost, and environmental benignity. Yet, the poor conductivity of sulfur, polysulfide shuttling and poor interfacial properties of lithium impede their commercialization.

Lithium–sulfur (Li–S) batteries are considered as futuristic energy storage systems owing to their high theoretical energy density, environmental benignity, and relatively low cost.

Magnesium-1,4-benzenedicarboxylic acid (Mg-TPA) and magnesium-1,3,5-benzene tricarboxylic acid (Mg-TMA) MOFs were synthesized and successfully incorporated in a poly (ethylene oxide) (PEO) matrix as filler for different proportions of LiN(CF3SO2)(2) (LiTFSI) as salt. The membranes prepared were thermally stable up to 360 degrees C. The ionic conductivity of the polymer electrolytes was enhanced upon addition of MOF and a maximum conductivity of 7.02 x 10(-4) S cm(-1) was achieved for CPE containing 10 wt % of Mg-TPA as filler. The interfacial properties of the CPEs with lithium metal anode were analysed by compatibility, Fourier transform infrared (FT-IR) and XPS analyses. Li/NCPE/Li symmetric cells were assembled and the dendrite growth was also studied. The lithium transference numbers (t (+)(Li)) was measured as 0.58 and 0.52 for the CPE containing Mg-TPA and Mg-TMA, respectively which is appreciable for battery applications. The influence of different organic ligands on the electrochemical and interfacial properties of solid polymer electrolytes was investigated and discussed. (C) 2019 Elsevier Ltd. All rights reserved.