Flow Electrode Capacitive Deionization (FCDI) Test Cell, CFCDITC

In the field of electrochemical water treatment, Flow Electrode Capacitive Deionization (FCDI) is an advanced evolution of traditional CDI. Unlike standard CDI, which uses static film electrodes that eventually saturate, FCDI uses a flowing carbon slurry (the flow electrode), allowing for continuous desalination without the need for a regeneration cycle. A typical FCDI test cell is a complex assembly that combines the principles of a plate-and-frame filter press with the fluid dynamics of a flow battery.

The test cell is generally symmetrical, consisting of several stacked layers: (1) Current Collectors: Usually made of high-purity Graphite plates or gold-coated titanium. They provide the electrical contact to the flowing slurry. (2) Flow Channels: Often CNC-machined into the graphite plates (serpentine or parallel patterns) to guide the carbon slurry. (3) Ion Exchange Membranes (IEMs): The AEM (Anion Exchange Membrane) is positioned near the positive electrode to allow anions (Cl-) to pass, while the CEM (Cation Exchange Membrane) is positioned near the negative electrode to allow cations (Na+) to pass. (4) Saline Water Chamber (Spacer): A middle compartment (often separated by a nylon mesh spacer) where the brackish water or seawater flows to be desalinated. (5) End Plates: Stainless steel or acrylic plates that bolt the entire stack together to ensure a leak-proof seal.

Part Number	CFCDITC (C-FCDI-FTC)
Structure/Components	Flow Plate: Graphite with serpentine channels Supporting Plate: Acrylic material Electrode Distance: 1.5 mm Tubing Connection Port: M5-3.8 (suitable for I.D. 4mm soft tubing.
Cell Manifold Size	4 cm * 5 cm (Channel width & depth: 2mm*2mm; Effective contact area with membrane: 10.9 cm2; Inner cell volume: 2.18 mL). Total cell size: 9cm*10cm. 5 cm * 6 cm (Channel width & depth: 2.4mm*2mm; Effective contact area with membrane: 16.3 cm2; Inner cell volume: 3.26 mL). Total cell size: 10cm*11cm. 6 cm * 7 cm (Channel width & depth: 2.8mm*2mm; Effective contact area with membrane: 22.8 cm2; Inner cell volume: 4.56 mL). Total cell size: 11cm*12cm.
Assembling Diagram
Flow Pump (Optional)	The regular-type flow pump with a standard flow rate of 3-10 mL/min can be provided with additional cost.           If a faster electrolyte pumping speed is needed, the following upgrade one can be supplied upon request.
Note	The cell components should be thoroughly cleaned and dried after use. Please don't use alcohol to clean the acrylic plates.

References:

1. H. M. Saif, et al., How should flow electrode capacitive deionization (FCDI) be operated to achieve efficient desalination and scalability?, Desalination, 2025, 606, 118769. 

2. C. Zhang, et al. Flow Electrode Capacitive Deionization (FCDI): Recent Developments, Environmental Applications, and Future Perspectives, Environ. Sci. Technol. 2021, 55, 8, 4243–4267.