Skip navigation

Electrochromic polymer systems

Electrochromic (EC) materials are known to change their optical properties/colour when an electrical voltage is applied. The term "EC module" refers to an electrochemical cell with which an electrochromic effect in solid film materials can be made technologically usable.


  • Information displays
  • Light filters for cameras
  • Sunglasses, visors
  • Building glazing
  • privacy screens, sunshades
  • transparent interior walls

The activities of the TITK (since 2007) in the field of EC modules include:

  • Synthesis and electro-optical characterisation of electrochromic polymers.
  • Development of ion storage layers (e.g. TiO2-CeO2), complementary EC polymers
  • Development of solid electrolytes based on ionic liquids
  • Manufacturing technologies for EC modules

Priorities and results achieved:

  • Coating processes of EC polymer, ion storage layer and electrolyte systems (spin coating, doctor blade technology, ink jet printing, spray, RzR).
  • Up-scaling of the individual components of the EC modules and manufacturing technologies on glass and flexible substrates (previously 400 cm2)
  • flexible curved transparent EC modules
  • UV resistance and long-term stability of the EC effect in a wide temperature range (long-term stability at RT: >10,000 cycles, EC contrast Δ%T: >50 (colourless / blue), EC efficiency (η): 300-800 cm2/C)
  • Switching speed between two colour states 5 to 30 sec
  • Wide colour range of EC modules (colourless / orange / blue, colourless / blue, yellow / brown / greyish blue, wine red / greyish purple / blue, wine red / dark purple