Reversible SOFC/SOEC Testing System with PLC and HMI Units, ERSOFECTS

An integrative testing system for Solid Oxide Fuel Cells (SOFC) and Solid Oxide Electrolysis Cells (SOEC) is a sophisticated laboratory or industrial rig designed to evaluate electrochemical performance, durability, and thermal cycling. Since these systems operate at high temperatures (600 °C to 900 °C), they require precise coordination between gas handling, thermal management, and electrical characterization.

An integrative test stand is generally composed of four primary modules: 

Thermal Management Module: (1) High-Temperature Furnace: Typically a split-tube or box furnace with multi-zone heating to ensure a uniform temperature profile across the cell or stack. (2) Pre-heaters: Used to heat incoming gases to the operating temperature before they reach the ceramic interface, preventing thermal shock. (3) Heat Exchangers: In larger "stack" testing, these recover heat from exhaust gases to improve system efficiency.

Gas Processing & Delivery (Balance of Plant): (1) Mass Flow Controllers (MFCs): High-precision units to manage fuel (H2, CH4, CO, NH3) and oxidants (Air, O2). (2) Humidification & Steam Generation: Critical for SOEC mode (electrolysis) and preventing carbon coking in SOFC mode. This involves a steam generator or a high-temperature "bubbler" with precise dew-point control. (3) Purge System: An automated N2 or Ar flush system to safely remove combustible gases during shutdown or emergency states.

Electrochemical Characterization: (1) Electronic Load (SOFC Mode): Dissipates the power produced by the cell to measure IV (Current-Voltage) curves. (2) Power Supply (SOEC Mode): Provides the high-current DC needed to drive the electrolysis reaction (splitting water or CO2). (3) EIS (Electrochemical Impedance Spectroscopy): A high-frequency analyzer used to distinguish between ohmic, activation, and mass-transport losses within the cell layers.

Control & Safety (PLC/HMI): (1) Logic Controller: Manages the "Recipes" (e.g., heating at 1 °C/min, then dwelling at 800 °C for reduction). (2) Safety Interlocks: Monitors for hydrogen leaks (via LEL sensors), over-temperature, and pressure imbalances between the anode and cathode.

Part Number	ERSOFECTS (E-RSOFEC-TS)
Power	AC110-220V±10%, single phase, 50/60 Hz, ~2000W.
Testing System Features	The whole testing system was composed of five units: gas flow, humidifier, furnace/cell fixture, PLC/HMI control, and safety protection.  The SOFC and SOEC modes can be easily switched. The whole testing cell fixture is made of alumina ceramic that avoids the potential contamination from metal.  Complete accessories, such as current/voltage terminal, thermocouple terminal, and gas inlet/outlet ports.  Dimension: W1200 * D800 * H1800 mm
Gas Flow Unit	Highly precise digital flow meter to control the gas flow rate and gas mixture/feeding. Bubble-type humidifier with independent gas and liquid heating modules to precisely control the dew point. The side bypass design enables the dry and wet flow gas switch. Power: AC220V±10%, 1200W Anode Gases: H2/N2/CH4/CO2/CO Cathode Gas: Air Input gas pressure: 0.1-0.3 MPa MFC flow range: 1-60 L/min MFC flow resolution: ±1.0% F.S.  Dew point range: 40-90 °C (resolution is ±1 °C) Tube fitting connection: 1/4" SWL (<20 L/min)
Furnace & Test Cell Fixture	The ceramic spring provides constant compression force on the ceramic test cell. The independent design of current and voltage wires eliminates the measurement derivation on voltage drop.  Furnace size: W300 * D300 * H260 mm Furnace heating temperature: RT-900 °C (resolution ±1 °C, multistage programmable) Tubing temperature: RT-200 °C Single Cell Size: 10-25 mm (Round or Square disk) or Planar 5cm*5cm or 10 cm*10cm Cell Fixture Dimension: W52 mm * D52 mm * H55 mm Pt Voltage Wire (φ 0.3mm); Pt Current Wire (φ 0.5mm); R-type thermocouple.
PLC & HMI Control Unit	All SOFC & SOEC operations can be realized on HMI touch screen It is capable of power control, gas flow rate control, temperature control, and data recording  Siemens brand PLC HMI Size: 10"
Safety Protection Unit	The safety system includes the temperature alarm, low water level alarm, gas leaking alarm and all alarm messages appears on HMI touch screen.  H2/CO leakage detector adopts electrochemical sensor that triggers the alarm even at low concentration.

References:

1. P. Li, et al., Electrochemical Performance of Pr0.4Sr0.5CoxFe0.9–xMo0.1O3−δ Oxides in a Reversible SOFC/SOEC System, Energy Fuels 2022, 36, 24, 15165–15176.
2. J. Pike, et al., Reversible SOFC/SOEC System Development and Demonstration, ECS Trans., 2023, 111, 1629.