Tubular lead acid batteries have long stood as a symbol of endurance, simplicity and affordability. They shaped the stationary energy storage landscape by offering deep cycle life and rugged operation. Yet a new wave of tubular design is emerging that could redefine the future: tubular redox flow batteries.
Ary L. C. Assunção, DSc. reviews this paper:
Fabian Brandes, Simon Ressel, Peter Kuhn, Armin Laube, Jasper Ramthun, Niklas Janshen, Antonio Chica, Claudia Weidlich, Michael Jeske, Simon Fischer, Thorsten Struckmann, Redox flow stacks with tubular cell design—Feasibility and performance, Journal of Power Sources, Volume 628, 2025, 235839, ISSN 0378-7753
In a remarkable study led by Dr. Thorsten Struckmann [1] at the Hamburg University of Applied Sciences and colleagues, published in the Journal of Power Sources (2025), the team demonstrated that extruded tubular redox flow cells integrated into stacks can deliver volumetric power densities above 750 W/L, with almost no performance loss from cell to stack. This achievement is not incremental improvement. It is a paradigm shift in modularity and cost efficiency.
While tubular lead acid batteries still depend on relatively heavy, semi-manual fabrication methods, the tubular redox flow approach enables co-extrusion, streamlined sealing and scalable mass production. It is the contrast between traditional casting and modern continuous extrusion: both create batteries, but only one scales seamlessly with industrial demand.
The philosophy also changes. For lead acid, tubular geometry maximized durability and utilization of active mass. For redox flow, tubular geometry becomes a tool to cut costs, simplify assembly and push stack reliability to new levels.
If tubular once meant longevity, today it could mean disruption. Thanks to the work of Dr. Struckmann and his team, we may be entering the second revolution of tubular batteries, not only for durability, but for unlocking scalable renewable energy storage.
References
- Fabian Brandes, Simon Ressel, Peter Kuhn, Armin Laube, Jasper Ramthun, Niklas Janshen, Antonio Chica, Claudia Weidlich, Michael Jeske, Simon Fischer, Thorsten Struckmann, Redox flow stacks with tubular cell design—Feasibility and performance, Journal of Power Sources, Volume 628, 2025, 235839, ISSN 0378-7753
- Tubular electrode, Klaus Rennebeck, Bernd Hildenbrand, Patent: WO2011110339A1