32
Discussion on Electrochemical Energy Storage Devices to cope with the
Alternating Energy Flow in YoYo-AWEC Fed Off-grid Systems
Nicolas Lewkowicz
Beuth Hochschule für Technik Berlin / University of applied sciences
Power delivery of AWECs using a YoYo operational pro-cedure is pulsed and needs to be buffered by energy stor-age systems with high power ratings and high cycling capabilities.
Analyzing the exact power requirements in off-grid sys-tems using an enerkíte as single power supply in three dif-ferent consumer configurations, leads to battery specifi-cations, that regular battery systems do not comply with. Searching for a cost efficient battery design, existing elec-trochemical systems will be discussed for energy efficiency, cost efficiency and cyclability. Alternative cell and assem-bly designs will be presented focusing on a bipolar elec-trode application.
While lead-acid batteries are still widely used for cost reasons, lithium-ion based batteries do reach higher en-ergy efficiency requiring more invest. Batteries consist of electrochemical cells, that need to be mechanically and
electronically integrated into energy storage systems. Sys-tem cost and performance is not only driven by the i.e. cost intensive lithium based materials, but as well by the com-ponent and production cost setting up the storage system. Cost reduction potentials can be addressed on the system layout according to the specific needs, the selected materi-al and the production process.
The addressed evaluations are part of a project called ECEWIN (ElectroChemical Energy storage for Wind energy fed Isolated Networks). In this project requirement analy-sis is carried out by the HTW Berlin, University of Applied Sciences, based on test data by enerkite. In the batteries lab of Beuth Hochschule, University of Applied Sciences, batteries are set up on a laboratory prototype scale in or-der to validate battery performance and cost estimation. The project is funded through the IFAF-Institute by beBerlin.
Nicolas Lewkowicz Beuth Hochschule für Technik Berlin University of applied sciences Luxemburger Str. 10 13353 Berlin Germany Lewkowicz@beuth-hochschule.de www.beuth-hochschule.de
