Acceleration of electrolyte absorption through optimized filling and wetting processes (Cell-Fi)

Project duration:
01.08.2016 – 31.07.2019


  • Institute of Machine Tools and Production Technology (IWF)
  • Institute of Machine Tools and Industrial Management (iwb)
  • Institute of Physical Chemistry (MEET)
  • Institute of Production Engineering of E-Mobility Components (PEM)
  • Fraunhofer Institute for Industrial Mathematics (ITWM)
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Technische Universität München
Fraunhofer Gesellschaft
RWTH Aachen
MEET Batterieforschungszentrum
Technische Universität Braunschweig

Against the background of the increasing relevance of electrical storage technologies for mobile and stationary applications, the economical production of suitable batteries in large quantities is a fundamental importance. The process step of electrolyte filling is a high capital commitment factor due to the long wetting and storage times. Despite the high potential to increase throughput and reduce costs, little scientific attention has been paid to the investigation of electrolyte filling. Best practice solutions are available, but the processes that dominate filling and wetting and how these can be accelerated have not yet been systematically recorded.

Within the framework of the Cell-Fi project, the topic complex of filling and wetting is therefore being scientifically investigated for the first time. The aim is to reduce the wetting times of large-format battery cells and to increase the resulting cycle times in the production of lithium-ion batteries.
In addition, it will be investigated which product and process parameters dominate electrolyte filling and how changes affect the wetting times and thus the performance of the cell. The wetting-relevant properties of the basic components are determined for this purpose. The electrolyte, electrode and separator properties and their dependencies on relevant process parameters are considered.

The process knowledge for filling and wetting and their influence on battery performance is then developed on prismatic pouch and hard case cells as well as round cells. By examining product and process parameters which are relevant for filling, potentials for reducing storage times can be uncovered and these can be reduced by suitable measures. The additional implementation in simulation models enables the transfer of the acquired knowledge to other material systems as well as different cell geometries and designs. The results achieved in the Cell-Fi project thus make a direct contribution to the development of economical storage technologies for mobile and stationary applications.