Composite Polymer Electrolytes Encompassing Metal Organic Frame Works: A New Strategy for All-Solid-State Lithium Batteries

Magnesium-benzene tricarboxylate metal organic framework (Mg-BTC MOF)-incorporated composite polymer electrolytes (CPE) composed of poly(ethylene oxide) (PEO) and lithium bistrifluoromethane sulfonylimide (LiTFSI) were prepared by a simple hot-press technique. The incorporation of Mg-BTC MOF in the polymeric matrix has significantly enhanced the ionic conductivity of CPE up to two orders magnitudes even at 0 °C. It also improved the thermal stability, compatibility, and elongation-at-break of the polymeric membrane. The all-solid-state lithium polymer cell composed of Li/CPE/LiFePO4 has delivered a stable discharge capacity of 110 mAh g–1 at 70 °C with a current rate of 1-C, which is higher than that of those reported earlier. The appealing properties such as high ionic conductivity, better compatibility, and stable cycling qualify this membrane as electrolyte for all-solid-state lithium batteries for elevated temperature applications.