As part of various sub-projects within the federal state-sponsored “Fast Storage BWII” project, ZSW is developing innovative coating technologies for nickel-based electrodes, active materials for the positive and negative electrodes in powercaps, as well as bipolar cell structures for high-performance applications.
Bipolar cell structures
Industrial energy storage systems need cost-effective solutions to achieve maximum performance. Normally, high-performance storage systems are more costly than energy-optimised storage systems. One way of avoiding this problem is to use bipolar structures because they have internal series connections with very low internal resistance. The need for an external cell connection is therefore reduced or completely eliminated. As part of the project, prototypes based on aqueous alkaline electrolytes are being developed for 12V, 24V and 48V voltage levels.
Development of active materials and electrodes
As well as investigating industrial electrodes as benchmarks, innovative active materials for the positive and negative electrodes in powercaps are also being developed. Particular attention is being paid to the high performance capacity of the newly produced materials. The electrochemical characterisation of the active materials is being performed at ZSW.
In addition, innovative, nickel-based high-surface contact electrodes are also being developed that allow a considerable increase in the current density. The initial investigation results show that on the basis of the high-surface contact electrodes discharge rates up to 470C can beb operated without substantial loss of capacity.