Fabrication of composite solid electrolyte based on MOF with functional ionic liquid for integrated lithium–air batteries

Li–air battery-based solid electrolyte can better protect the lithium anode from the corrosion of other components and effectively block the risk of ignition and explosion caused by the lithium dendrite penetrating the dielectric layer. In this work, Li-containing ionic liquid (Li-IL) is absorbed in NH2-MIL-101(Cr) metal–organic frameworks (MOFs) to form a functional filler and further incorporated the filler into polyethylene oxide (PEO) to fabricate composite solid electrolyte (Li-IL@NH2-MIL-101(Cr)/PEO). The lithium anode and the air cathode were modified with Li-IL@NH2-MIL-101(Cr)/PEO, and the integrated solid-state Li–air batteries were prepared by roller pressing. Taking advantage of nanostructured Li-IL@NH2-MIL-101(Cr), fast lithium–ion transportation is achieved in the bulk and across the electrode/electrolyte interface. As a result, the ionic conductivity of the Li-IL@NH2-MIL-101(Cr)/PEO reaches 3.1 × 10–4 S/cm, the Li–air battery using the Li-IL@NH2-MIL-101(Cr)/PEO as solid electrolyte exhibited a high specific capacity of 11,682 mAh/g and remarkable cycling stability of 122 cycles.