SolaBat - Solar cell meets battery - Realization of a hybrid energy system

Energy research, with all its scientific and economic facets, is con-sidered to be one of the most important interdisciplinary challenges we are faced with in the 21st century. If we are to succeed on a global dimension, we need better, cheaper and “greener” energy sources directly coupled with advanced and reliable energy storage systems. In particular, as the solar radiation is, by its very nature, an intermittent energy source, the existence of an advanced energy storage system is highly desired for buffering energy harvested by photovoltaic cells. The key idea of SolaBat is to directly couple the junction of a photo-voltaic device with a Li-ion battery material without any additional wiring. A device built on this principle should be able to supply ener-gy, for a while, also in the absence of illumination thanks to its intrin-sic storage function. The project brings together energy storage and conversion; featuring a holistic approach the final goal is pursued on four research lines that converge towards the realization of the hybrid device: (A1) Materials for the Li-ion battery side and (A2) for the PV side (B) Assembly of the hybrid device and materials compatibility study (C) Structural and morphological investigation of interface ef-fects and reactions at the interfacial regions The studies will at first be oriented towards developing the suitable materials and structures able to perform in a hybrid device. Under-standing the materials compatibility issues that may arise during the assembly and operation constitutes a key element that would enable a successful device. Finally, relevant interfacial aspects such as electrochemical stability as well as the structure-related properties of materials for hybrid devices will be covered through fine microscopic studies of the interfaces. We expect that the studies performed will open a broader way to-wards the realization of hybrid energy devices by understanding many of the materials-related aspects and the possibilities offered by this concept. We expect to achieve a functional hybrid device at laboratory scale and evaluate its characteristics and limitations. On a longer term, the proposed hybrid energy systems may lead to a change in paradigm about how solar energy is harvested and stored.