Supercapacitors

People in charge : Pierre-Henri Aubert

Supercapacitors conductive electrodes were developed as hybrid nanocomposites, from the nanostructuration of electronic conductive polymer (PCE) by using aligned carbon nanotubes (NTCa).

The main issue was to precisely control the PCE deposition along NTCa by electrosynthesis in an ionic liquid medium. Thus, a sequenced electrosynthesis process allows the monomer’s diffusion to NTCa’s electrodes, which can then be coated homogeneously.

Electropolymerization of 3-methylthiophène along NTC. Picture by scanning
electron microscopy of the NTCa after electropolymerization.

The nanostructured material’s capacity is increased by 35% from 95F/g without NTCa to 126F/g in the case of nanocomposite. This process has been extended to other PCEs such as polypyrrole, PEDOT, polycarbazole and polythiophene, but also to their copolymers. In addition, and for special conditions of synthesis, hybrid nanocomposite is obtained as an autosupported and flexible conductive film.

What’s more, separator membranes for supercapacitors are also developed from POE based materials and ionic fluid inflated elastomers. These membranes perform over a wide range of temperatures (-60°C – 100°C).