Using a Metal Oxide Nanoparticle Interlayer To Efficiently Anchor Polysulfides at High Mass Loading S-Cathodes in Li–S Rechargeable Battery

Abstract

The bulk of the work related to a Li–S rechargeable battery revolves around materials design strategies of a suitable carbon­(/noncarbon)–host matrix targeted toward the entrapment of sulfur and prevention of leaching out of polysulfides into the electrolyte. This strategy, however, limits the extent of sulfur loading and, depending on the host, may simultaneously increase the unutilizable mass of sulfur in the electrode. Recently, usage of interlayers between conventional S|C composite cathode and separator has been demonstrated in Li–S batteries. This interlayer, mostly carbon or doped carbon, has been used to trap the polysulfides in between the interlayer and S-cathode. Instead of carbon, we demonstrate here an alternative and novel interlayer of metal oxide nanoparticles between cathode and separator to efficiently trap and arrest the polysulfides at the S-cathode. Oxide-based compounds exhibit a superior ability to hold the lower order polysulfides toward the S-cathode by bonding interactions, thereby enhancing anode protection. We employ pseudocapacitive metal oxides viz. Ni­(OH)2 and NiO as the interlayers for efficient anchoring of the polysulfide. In the presence of the Ni­(OH)2/NiO nanoparticle interlayer, an alternative pathway for sulfur reduction and oxidation takes place which simultaneously leads to a phenomenal reduction in the polysulfide shuttle effect, even at extremely high loadings of sulfur (up to 15 mg cm–2). The beneficial role of the interlayers in inhibiting the shuttle effect is studied via in depth ex situ UV–vis and powder X-ray diffraction of the battery separator and the interlayer, respectively, cycled at various depths of discharge and charge. The conventional Li–S cell with S/C composite cathodes and metal oxide interlayers exhibits a remarkable improvement in both cycliability and rate capability (range: C/10–5C) vis à vis the cell without any interlayer.

Metal-based nanostructured materials for advanced lithium–sulfur batteries

“…Nanostructured metal hydroxides with hydrophilic groups and a functional polar surface have been recently investigated as promising cathode host materials for Li-S batteries, such as Co(OH) 2 nanosheets, 390 Ni(OH) 2 nanoparticles, 125,391,392 Ni(OH) 2 hollow spheres, 393 Ni 3 (NO 3 ) 2 (OH) 4 shells, 394 layered double hydroxides, 395,396 and so on. In 2015, Nie et al reported Co(OH) 2 nanosheets as a conceptually new metal-containing nanostructured material to obstruct the LiPS shuttling and prolong the service life of Li-S cells.…”

High-Performance Li-Metal-Free Sulfur Battery Employing a Lithiated Anatase TiO2 Anode and a Freestanding Li2S–Carbon Aerogel Cathode

“…This was found to be the optimal concentration for the absorbance measurements. The control sample was prepared by dissolving 120 μL of 1 M of LiTFSI and 0.2 M of LiNO 3 in 3 mL of DOL/DME (1:1 v/v), which was further diluted four times . All of the electrolyte preparations and cell disassembly for the present study were carried out in an (MBraun) glovebox with H 2 O and O 2 levels less than 0.5 ppm.…”

LiNi0.6Co0.2Mn0.2O2 Cathodes Coated with Dual-Conductive Polymers for High-Rate and Long-Life Solid-State Lithium Batteries

“…With the development of battery technology, extensive attention has been paid to the improvement of safety and energy density. − Nowadays, it is difficult to further increase the energy density of commercial lithium-ion battery (LIB) systems, especially concerning the safety issues. − Replacing the flammable organic electrolytes with the stable solid electrolytes (SEs) is viewed as one of the most effective ways to improve the energy density and safety − because the SEs offer the capability of using the high-specific capacity lithium metal anodes and the high-voltage cathodes. , Furthermore, concerning the achievement of high energy density, cathodes with high mass loading and excellent kinetics are necessary. In previous reports, − a large number of electronically and ionically conductive additives were added in the cathodes, which took 20–30 wt % of the total mass of the cathode in order to form a continuous conductive network. This caused reduced occupation of active materials, hindering the improvement of energy density …”