An increasing fraction of renewable energies is expected to contribute to the global energy demand in the future and energy storage systems are needed for an efficient use of discontinuous sources such as wind and solar power. In this context, nanostructured architectures employing a 3-D structuring for power storage and conversion (batteries, supercapacitors, hydrogen storage materials, fuel cells, photovoltaics) provide many advantages over existing technologies to minimize power losses, improve charge/discharge rates, and enhance energy densities, because functional units in these architectures consist of interconnected ~10 nm domains and mesopores (10-50 nm), for example. In this regard, nanoscience and nanotechnology offer promising approaches as all the elementary steps of energy conversion (charge transfer, molecular rearrangement, chemical reactions, etc.) take place on the nanoscale.
The work on batteries focuses on the development of Novel Battery Chemistries involving new shuttle mechanisms based on singly charged negative ions such as F, Cl and the shuttle of Mg. Mg batteries are safe and can reach very high energy densities. The theoretical energy density of the Mg/S couple is 4000 Wh/L. In addition, nanostructured cathode materials are developed for Li ion batteries which are based on reactive nanocomposites. The aim is to develop materials with gravimetric energy storage capacities that are considerably above those of current battery materials (i.e. approx. 250 Wh/kg). Targeted properties are the energy capacity, the power density, the cycling stability, and the sustainability of the materials.