1. Skolkovo Institute of Science and Technology; Nobel str. 3 Moscow 143026 Russia
2. Canatu Oy; Konalankuja 5 FI-00390 Helsinki Finland
3. DLR Institute of Networked Energy Systems, German Aerospace Center (DLR); Carl-von-Ossietzky-Straße 15 26129 Oldenburg Germany
4. Department of Materials and Environmental Technology, Tallinn University of Technology; Ehitajate tee 5 19086 Tallinn Estonia
5. Department of Applied Physics, Aalto University; P.O. Box 15100 FI-00076 Espoo Finland