Cross-Linked Solid Polymer Electrolyte for All-Solid-State Rechargeable Lithium Batteries

Semi-interpenetrated network Solid Polymer Electrolytes (SPEs) were fabricated by UV-induced cross linking of poly(ethyleneglycol) diacrylate (PEGDA) and divinylbenzene (DVB) within a poly(ethyleneoxide) (PEO) matrix (M-w = 5 x 10(6) g mol(-1)), comprising lithium bis(trifluoromethanesulfonyl)imide salt (LiTFSI), at a molar ratio of EO:Li similar to 30:1. The influence of the DVB content on the final SPE properties was investigated in detail. An increase of DVB concentration resulted in self-standing polymer electrolytes. The DVB cross-linker incorporation was found to decrease the crystallinity of the PEO matrix from 34% to 23%, with a decrease in the melting temperature (T-m) of the membrane from 50 degrees C to 34 degrees C. Moreover, the influence of the DVB concentration on the ionic conductivity was determined for polymer electrolytes with 0,10, 20 and 45% DVB from room temperature (RT) to 80 degrees C. The resulting SPEs showed a high electrochemical stability of 4.3 V as well as practical conductivity values exceeding 10(-4)S cm(-1) at 70 degrees C. Cycling performance of these semi-interpenetrated SPE's have been shown with a Li metal polymer battery and all solid-state Li sulphur battery. (C) 2016 Elsevier Ltd. All rights reserved.