Energy storage systems, both for mobile as well as stationary applications, are essential for the energy revolution and for achieving climate targets. Yet, the requirements on energy storage systems vary greatly depending on the field of application.

In the mobile sector, energy, and power density as well as fast charging capability are highly important. In the stationary sector, the importance of this is decreasing and more value can be placed on criteria such as environmental friendliness, safety, and resource availability.

It is thus not a matter of developing a technology for each field of application, but rather a suitable technology for each field of application. While there is still no alternative to lithium ion accumulators in the mobile sector, the situation is changing in the stationary sector.

The aqueous sodium ion represents such an alternative. They are environmentally friendly, inexpensive, safe and the resources used are available worldwide. Particularly the use of aqueous electrolytes is providing a plethora of advantages: The storage is a robust, low maintenance system, that is neither flammable nor toxic and thus incorrect operation does not result in any serious consequences. However, this technology is still in the embryonic stages of development and exhibits great potential for optimisation in the areas of performance, cycle stability and loading speed.

The research goal of this cooperative doctoral degree is to improve these properties without diminishing the stated benefits. The development approach is based on a variation of the electrode composition (optimising the ratio between active material/conductive additive), of the mixing process (optimising distribution of electrode components) as well as applying the electrode mass on the current collector (reduction of internal resistance).