High performance functionalized cellulose membranes for Fuel Cell – ionMcell

The development of proton exchange membrane fuel cells, which aim to convert hydrogen into electricity, is essential in the context of the energy transition. The advantage of this electrochemical process is that it is non-polluting, generating mainly water. In such a cell, the gas separating and proton conducting membrane is a key element. It is usually made of perfluorinated sulphonic acid ionomers (e.g. Nafion) which suffer from serious drawbacks: very high cost, poor recyclability, poor performance above 80°C and at low relative humidity.
The ionMcell project aims to combine the expertise of recognized academic laboratories and technical centers on biobased materials (CERMAV, CTP, FCBA) and on ion-conducting polymers (SyMMES) in order to establish cellulose, which is derived from an abundant and renewable biomass, in the world of fuel cells by designing low-cost and durable proton exchange membranes. The aim is to further develop the mechanical and conductivity properties as well as durability of sPEEK-based (non-fluorinated) membranes using chemically functionalized cellulose nanocrystals (CNC) or nanofibrils (MFC) fillers. This functionalization (e.g. periodate oxidation, sulfonation) will increase the content of anionic sites in the matrix to improve the proton conduction properties of the biocomposite. To go further, functionalized CNCs or MFCs will be used for the design of all cellulose membranes. For both types of membranes, several cellulosic sources and processes for the production and chemical modification of the fibres will be tested offering various aspects of shape and structure. A wide range of advanced multi-scale analyses from molecular to cell tests (e.g. electron microscopy, near field) will be used to characterize the resulting building blocks and membranes.