Development of electrolyte systems

Electrolyte development for lithium-ion batteries (LIB) aims to increase safety while maintaining or increasing performance and energy density. Established electrolyte systems in LIBs generally contain highly volatile and therefore flammable organic solvents as well as components that cause chemical burns on contact with water. Higher cell voltages are sought to increase the energy density. However, the electrochemical stability of standard electrolyte systems is not sufficient for cell voltages above 4.5 V.

Our approach:

  • Replacement of the highly volatile organic solvents with ionic liquids (IL).
  • Influence of active inorganic fillers on safety and electrolyte performance.
  • Comprehensive knowledge of the physical and (electro)chemical behavior and its modeling.
  • Use of ion-conducting polymers as electrolyte matrix.
  • Targeted selection of additives with regard to electrolyte and cell chemistry.


The focus of the work is the targeted development of suitable electrolytes for high-energy lithium-ion batteries. Important material properties are systematically researched, taking into account the water content and temperature.

  • Rheological properties using rotational viscometry under inert gas
  • Electrochemical impedance spectroscopy (EIS, frequency range 10-1- 4-106 Hz)
  • Electrochemical stability via cyclic voltammetry
  • Interfacial analysis
  • Thermal decomposition behavior via differential scanning calorimetry (DSC)
  • Wetting behavior on electrode materials via drop shape analysis
  • Density and density change of electrolyte mixtures (oscillating U-tube method)
  • Gas chromatography of liquid and gaseous components


If you have any questions on this topic, please contact Dr. Andreas Hofmann.