Current batteries primarily rely on the use of liquid electrolytes composed of flammable solvents that are unstable in contact with lithium metal, posing safety issues. The development of gel polymer electrolytes (GPEs) is expected to lead to new generations of safer batteries. To maintain their environmental relevance, these new batteries should ideally be made of bio-based materials, have an extended lifespan, and be recyclable. In this context, this thesis aims to develop bio-based GPEs cross-linked by vitrimer chemistry that allows for their recyclability. The swelling of electrolytes in green, non-flammable deep eutectic solvents (DESs) is considered to achieve ionic conductivities greater than 10-4 S.cm-1 at room temperature. The PhD student will study the influence of the chemical structure of the polymer and the DES on the physicochemical, mechanical, and electrochemical properties of these eutectogels to optimize their formulation for integration into a complete pouch-cell system.