02184nas a2200217   4500008004100000022001400041245010000055210006900155260000800224300001200232490000600244520143500250653002901685653001701714653002701731653001501758653001901773100002101792700002501813856012801838       2019                        eng d  a2194-428800aSeparator membranes for lithium-sulfur batteries: design principles, structure, and performance0 aSeparator membranes for lithiumsulfur batteries design principle  cJUN  a18008190 v73 a<p>Improvement in electrical energy storage systems is one of the most recent research topics of great academic and industrial interest. Lithium-sulfur (Li-S) battery systems offer a theoretical energy density an order of magnitude larger than the popular Li-ion batteries. The principle of working, inherent challenges in utilizing this system for commercial applications, and the various approaches taken to address these challenges are herein discussed in detail. The polysulfide shuttle effect is a major concern that deteriorates electrochemical performance in this system. In the recent past, electrodes have been intricately engineered to tackle this problem. However, more recently, the focus has shifted to the critical role of the separator. Modifying conventional separators or fabricating novel structures to enhance the cell performance appears to be a more feasible option. Some design principles that are critical to the functioning of a separator in Li-S batteries, namely physisorption, chemisorption, and electrostatic repulsion, are discussed. Many recent papers proposed novel cell configurations with specifically designed functional separators. These reports are classified according to three design principles, analyzed critically, and compared with a view to assess their relative merits and efficacy. Some thoughts on the future directions in the development of an efficient separator are described.</p>
10alithium-sulfur batteries10apolysulfides10arechargeable batteries10aseparators10ashuttle effect1 aGupta, Aritrajit1 aSivaram, Swaminathan  uhttps://library.ncl.res.in/content/separator-membranes-lithium-sulfur-batteries-design-principles-structure-and-performance02392nas a2200205   4500008004100000245009400041210006900135260000800204490000600212520167000218653002101888653001301909653002901922653001801951653001701969100002101986700002102007700003002028856012802058       2023                        eng d00aCan metal cations electrocatalyze sulfur redox reaction and suppress polysulfide shuttle?0 aCan metal cations electrocatalyze sulfur redox reaction and supp  cSEP0 v63 a<p>
	In lithium-sulfur (Li-S) batteries, sulfur undergoes various changes. It switches between cyclic structure and linear structure. The charge on the sulfur varies between a neutral state and a negative charge-bearing state. Due to these changes, the sulfur/polysulfide dissolves in the battery electrolyte. Furthermore, the kinetics of the sulfur redox reaction is sluggish. Therefore, a material that can suppress sulfur/polysulfide dissolution and electrocatalyze sulfur redox reaction is needed. We hypothesize that the polysulfide dissolution can be suppressed if the host exhibits polyvalent electrostatic attraction. Polysulfide is a negative charge-bearing molecule; hence the host must comprise multiple positive charges. Nickel cations with other heteroatoms have been explored as a host in Li-S batteries. The heteroatoms impart additional interactions. The easier way to circumvent the effect of heteroatoms is the addition of metal salts. However, metal salts can either exhibit monovalent or divalent attraction with polysulfides. Those interactions are weak and we must have polyvalent interaction. Towards this objective, we have designed and synthesized a material that comprises multiple divalent cations that is also devoid of heteroatoms. The Li-S batteries fabricated using the metal cation immobilized graphene showed a maximum specific capacity of 1022 mAh/g at 0.1 C rate. Among the metal cations, nickel cations showed better performance than cobalt cations. Thus, we demonstrate that metal cations immobilized on Graphene can efficiently electrocatalyze the sluggish sulfur redox reaction and suppress the polysulfide dissolution.</p>
10aelectrocatalysis10agraphene10alithium-sulfur batteries10ametal cations10apolysulfides1 aKumar, Subramani1 aSwain, Gitanjali1 aKrishnamoorthy, Kothandam  uhttps://library.ncl.res.in/content/can-metal-cations-electrocatalyze-sulfur-redox-reaction-and-suppress-polysulfide-shuttle02362nas a2200253   4500008004100000022001400041245011700055210006900172260000800241300001100249490000800260520147100268653002401739653002701763653002701790653001701817100003001834700002501864700002301889700001701912700002101929700002901950856012901979       2026                        eng d  a0378-775300aEffect of imidazolium-based porous polymer binder on the electrochemical performance of lithium sulfur batteries0 aEffect of imidazoliumbased porous polymer binder on the electroc  cJUN  a2399140 v6763 a<p>
	Severe polysulfide shuttle and poor conversion kinetics remain as barriers to make Li-S batteries practically viable. Polymer binders are an important component of a battery electrode although its dosage is very small. Traditionally employed PVDF binder in Li-S batteries has no significant impact in either suppressing the polysulfide shuttle or on their conversion kinetics. Ideally, the binder for a Li-S battery should suppress the polysulfide shuttle, promote the polysulfide conversion and buffer the volume expansion during charge-discharge process. Towards this direction, herein we present a new octyl imidazolium-TFSI based porous polymeric binder (PImz) in combination with CNT/S/Nickel(II) phthalocyanine tetrasulfonic acid tetrasodium salt (Na-NPT) composite. The binder offers strong polysulfide immobilizing capabilities through electrostatic interaction with the imidazolium nitrogen and pore confinement through its porous network, while a small amount of Ni-phthalocyanine could enhance the polysulfide conversion kinetics. Li-S batteries with PImz binder delivered a high specific capacity of 805 mA h/g (0.5 C) with stable performance over 300 cycles. Furthermore, the batteries with high sulfur loading similar to 3 mg/cm(2) delivered a capacity of 820 mA h/g. This newly designed porous polymeric binder is a promising and efficient alternative to the traditionally employed PVDF in terms of synthesis, cost, performance and safety.</p>
10aImidazolium polymer10alithium sulfur battery10aNa-NPT electrocatalyst10apolysulfides1 aSenthilkumaran, Marimuthu1 aBharathkumar, H., J.1 aRamesh, Sivalingam1 aBasha, Anver1 aNanaji, Katchala1 aBabu, Rajendran, Prakash  uhttps://library.ncl.res.in/content/effect-imidazolium-based-porous-polymer-binder-electrochemical-performance-lithium-sulfur