single-ion conductor; polysulphide shuttle; graft copolymerization; lithium-sulphur battery; solid polymer electrolyte; polymer electrolyte; lithium-metal battery
Conder Joanna, Villevieille Claire, Trabesinger Sigita, Novák Petr, Gubler Lorenz, Bouchet Renaud (2017), Electrochemical impedance spectroscopy of a Li–S battery: Part 2. Influence of separator chemistry on the lithium electrode/electrolyte interface, in Electrochimica Acta
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Conder Joanna, Villevieille Claire, Trabesinger Sigita, Novák Petr, Gubler Lorenz, Bouchet Renaud (2017), Electrochemical impedance spectroscopy of a Li–S battery: Part 1. Influence of the electrode and electrolyte compositions on the impedance of symmetric cells, in Electrochimica Acta
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Conder Joanna, Bouchet Renaud, Trabesinger Sigita, Marino Cyril, Gubler Lorenz, Villevieille Claire (2017), Direct observation of lithium polysulfides in lithium-sulfur batteries using operando X-ray diffraction, in Nature Energy
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Conder Joanna, Forner-Cuenca Antoni, Müller-Gubler Elisabeth, Gubler Lorenz, Novák Petr, Trabesinger Sigita (2016), Performance-enhancing asymmetric separator for lithium−sulfur batteries, in ACS Applied Materials & Interfaces
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Joanna Conder, Sigita Urbonaite, Daniel Streich, Petr Novák, Lorenz Gubler (2015), Taming the polysulphide shuttle in Li–S batteries by plasma-induced asymmetric functionalisation of the separator, in RSC Advances
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The scientific vision of the proposed project is to understand the design of functional polymer electrolyte membranes based on the grafting approach. Such membrane could be used for future lithium-sulphur batteries, where conductivity for Li+-ions is needed but the passage of polysulphide anions is not desired More precisely, one of the challenges in using sulphur as positive electrode material is the solubility of the partially reduced lithium polysulphides (Sn2-, n = 3-6) in the liquid electrolyte, and this leads to massive self-discharge and specific capac-ity loss. Therefore alternative approach must be identified and scientifically understood.Our approach to tackle this issue is the use of single Li-ion conducting polymers in the form of cation exchange membranes. Such membranes were already described, however, the con-ductivity of these polymers is too low. It is envisaged as a primary approach in the proposed project to study composite porous membranes with a thin cation exchange barrier layer (poly-mer ‘skin’), allowing selective Li-ion transport. The approach is based on the established con-cept used in separation membrane technology, where asymmetric porous membranes are coated with a thin polymer layer on one side to provide selectivity for molecules of specific sizes. Here, the Donnan exclusion of anions by a cation exchange ionomer is exploited. The functionalisation of the macroporous substrate will be carried out by grafting cation ex-change groups into surface-near regions.In addition, the modification of more traditional polyethylene oxide (PEO) based solid polymer electrolytes for Li-ion batteries will be explored by introducing grafted cation exchange groups. This will enhance the rejection of polysulphide anions and, additionally, prevent the crystallisation of the PEO, which severely impairs Li-ion conductivity.The proposed study is aimed at identifying polymer architectures for single Li-ion conducting composite electrolyte membranes with polysulphide rejection properties and gaining an un-derstanding of composition-structure-property relationships regarding the functioning of the material in the lithium-sulphur battery.