Abstract
Energy obtained by wind turbines can be foreseen to constitute a significant part of the future energy sources. A major challenge is however the large variation over time in wind energy production. Energy conversion from electricity to storable energy is therefore a key technology to master, and it is therefore important to develop compact, reliable, cheap and energy efficient equipment for this. An obvious solution is production of hydrogen based on water alkaline electrolysis. In the work presented the atmospheric plasma spraying (APS) of Raney nickel (50/50 Ni/Al) was used to develop electrodes with a large specific surface area as well as a considerable energy efficiency in high temperature water alkaline electrolysis. The coating process was analyzed using a plume analyzer as the primary tool and the coating properties were analyzed by a combination of bonding strength measurement, optical (OM) and scanning electron microscopy (SEM) as well as testing of the activated electrodes in a laboratory electrolysis cell. The results of the spraying process analysis are reported together with the electrochemical properties of the activated electrodes, and with regard to energy efficiency very positive results are obtained for the measured overvoltage.
