Nanoscale microfibrillated cellulose reinforced truly-solid polymer electrolytes for flexible, safe and sustainable lithium-based batteries

Fully-solid methacrylic-based thermo-set polymer electrolyte membranes reinforced with nanoscale micro-fibrillated cellulose (MFC) fibres are here presented. The preparation is carried out in water and the membrane is obtained by an easy and reliable UV-induced polymerisation via a free radical mechanism; thus, the overall process is highly energy efficient and environmentally friendly. The morphology of the composite electrolytes as well as the mapping of the elements present in the system is investigated by scanning electron microscopy, while the thermal behaviour is investigated by thermo-gravimetric analysis and differential scanning calorimetry. The composite polymer electrolytes prepared by MFC fibres reinforcement exhibit excellent mechanical properties with a Young’s modulus as high as 32 MPa. Acceptable ionic conductivity values (above 0.1 mS cm−1 at 50 °C) and good overall electrochemical performances are maintained, ensuring that such specific approach would make these hybrid organic, cellulose-based composite polymer electrolyte systems a strong contender in the field of thin and flexible fully-solid lithium based power sources, especially for moderately high temperature applications.