UltraThinFlow - Development of Ultra-Thin Redox Flow Cells with Ingenious Flow Technology

The Chair of Electrochemical Process Engineering is a partner in the UltraThinFlow (UTF) collaborative research project, which is funded by the Federal Ministry of Research, Technology and Space (BMFTR). The aim of the project is to develop a new generation of ultra-thin redox flow battery stacks with higher power density through reduced electrode and cell thickness, optimised electrolyte flow and advanced electrode design. By combining novel cell architectures, advanced porous electrodes and operando analysis techniques, UltraThinFlow aims to improve the performance and compactness of stationary redox flow battery systems for the integration of renewable energy.

Project Profile

UltraThinFlow brings science and industry together to overcome key limitations of today’s redox flow batteries. The focus is on developing ultra-thin electrodes with optimised pore structures, improved conductivity, wettability and electrochemical activity – combined with an advanced cell architecture and flow field design. The aim is to reduce energy losses, improve electrolyte distribution, save on materials and increase the power density of the systems.

The University of Bayreuth is contributing its expertise in the development of porous carbon electrodes. Commercial and newly developed carbon felts are being specifically modified – for example, through heteroatom doping and tailored surface functionalisation – to create catalytically active surfaces whilst maintaining high conductivity. Comprehensive material characterisation (including Raman spectroscopy, XPS, XRD, SEM/EDX, EIS, TGA-FTIR-MS) helps to understand the relationships between structure and properties and to optimise activation strategies for high-performance electrodes.

Another key focus is the development of an operando X-ray radiography platform that enables the visualisation of electrolyte flow and distribution in ultra-thin electrodes under realistic operating conditions – with a view to also utilising X-ray tomography and synchrotron-based techniques in the future.

Duration: 01.04.2026 - 31.03.2029

Founding: Federal Ministry of Research, Technology and Space (BMFTR)

Project Partners:

• Fraunhofer Institute for Chemical Technology (ICT)
• J. Schmalz GmbH

Contact: Prof. Dr.-Ing. Christina Roth, Dr. Daniel Leykam, Ajay Benny