Battery Electrolytes

Batteries and supercaps are both energy storage devices, the main difference between them being the time scale on which the stored energy could be released. While batteries can store energy for months or even years, discharging of supercaps is faster. At the same time the energy storage density of capacitors is much higher, and hence more energy can be released in less time. As a consequence, the areas of use for the two devices are different.

In batteries and supercaps, electrochemical processes (charging and discharging) take place, that are fundamental to their ability to store and deliver energy. For charge transfer between the electrodes of the devices, electrolytes are required. The general technical specifications for these electrolytes are very similar for both systems.

Ionic liquids are very interesting electrolytes for lithium ion batteries and supercaps due to their outstanding properties, i.e. high electrochemical stability towards oxidation and reduction processes, high electric conductivity (up to 27 mS/cm for neat substances and 70 mS/cm for mixtures with organic solvents) and wide electrochemical windows (up to 6 V and above).

For both lithium ion batteries and supercaps, there is no common state-of-the-art with regard to the technology used to build them, since many different producers market their specifically developed products. Thus, depending on the actual product, the electrolyte  has to fulfill very specific requirements. Despite a large number of products already on the market there is still a strong need for further development. This became patently obvious only recently when the computer manufacturer Dell experienced major problems with lithium ion batteries produced by Sony. In some cases the batteries caught fire on overheating, which posed a considerable safety hazard to users. Another very specific challenge is the use of supercaps in hybrid vehicles. Here, the energy generated during braking is stored temporarily and then used for subsequent acceleration. Recent advances by Toyota has put enormous pressure on the automotive industry to further their research in this field.

One of IoLiTec's current research activities is centred around the development of special electrolytes for use in lithium ion batteries and supercaps. These electrolytes are based on ionic liquids and contain certain performance-enhancing additives.

Further information on products from the lithium ion batteries and supercaps range can be accessed by clicking on the corresponding link in the menu on the right.

If you have any questions regarding our activities, applications or products in this field please feel free to contact us.