Simple twist of fate – novel boltless construction for a lab-scale redox flow battery cell

• Boltless redox flow battery cell design with threaded “lid and jar” assembly. • Fast and easy assembly compared to the conventional redox flow cells. • Lab-scale 3D-printed prototype, a proof of concept. • Performance validated through battery cycling and EIS. • Alternative to the conventional design with no polyolefin sealing. This article presents a novel, 3D-printed lab-scale redox flow battery (RFB) cell featuring a “lid and jar” assembly method instead of the conventional sandwich-like structure connected by bolted joints. The cell is sealed by screwing a threaded ring onto the complementarily threaded casing of the reactor module instead of multi-bolt assembly requiring specific tools, assembly methods and experience, resulting in a simpler and faster assembly process without the need for additional sealing. This approach is particularly beneficial for research applications requiring frequent assembly and disassembly of the cell. Additionally, utilization of 3D printing allows for comparatively easy manufacturing and personalized modifications of the device, resulting in less material loss compared to conventional production methods. The prototype, manufactured using stereolithography (SLA) technology, was subjected to electrochemical testing, including charge and discharge cycling as well as electrochemical impedance spectroscopy (EIS). The obtained results were compared with those from a commercially available lab-scale RFB cell by Pinflow energy storage s.r.o. Electrochemical measurements were performed to verify the basic functionality of the proposed design and as a proof of concept. Detailed analysis of electrochemical behavior is beyond the scope of this study, as the aim is to improve the assembly method rather than the overall battery efficiency.