Advanced EIS Solutions for Electrolysis and Fuel Cell Development
Scalable Solutions for Every Stage of Hydrogen Technology Development
Understanding electrochemical behavior in fuel cells and electrolysis systems requires precise, high-resolution measurement solutions. HIOKI’s ALDAS Fuel Cell Analyzers provide deep insight into electrochemical processes using advanced electrochemical impedance spectroscopy (EIS), going beyond conventional I-V testing.
The portfolio includes three scalable solutions:
- ALDAS- α for compact, flexible electrolysis cell analysis in laboratory environments
- ALDAS- Mini for high-speed, multi-channel EIS measurements in advanced R&D
- ALDAS-E for in-operation analysis of kW to MW-class fuel cell and electrolysis stacks
HIOKI’s three ALDAS systems provide detailed analysis of internal resistances, reaction kinetics, and degradation mechanisms across applications from single cells to large-scale stacks – helping to accelerate development cycles and ensure reliable validation.
3 Products
ALDAS-E
ALDAS-E – EIS Measurement System for kW to MW-Class Electrolysis and Fuel Cell Stacks
The ALDAS-E is a high-performance electrochemical impedance spectroscopy (EIS) system designed for in-operation analysis of large-scale electrolysis and fuel cell stacks. It enables precise impedance measurement under real operating conditions, enabling engineers to evaluate performance, identify losses, and monitor degradation in kW to MW-class-fuel cell and electrolysis systems. A key strength of the system is its ability to handle very high currents. By combining multiple current sensors, ALDAS-E supports measurements up to 10 kA, while still detecting small AC signals within noisy DC environments, which is critical for realistic stack evaluation. The ALDAS-E system offers scalable multi-channel measurement up to 48 channels, enabling simultaneous observation of both total stack behavior and individual cell performance. This makes it ideal for detailed stack diagnostics, comparative analysis, and electrolysis and fuel cell stack optimization. Despite the complexity of large-scale systems, ALDAS-E is designed for easy integration, connecting to existing setups without requiring dedicated power supplies or system modifications. The fast EIS measurement below 8 minutes and its high stability down to low frequencies, ALDAS-E significantly reduces evaluation time while maintaining high accuracy.ALDAS-E represents the high-end solution for applications that go beyond the scope of the high-speed ALDAS-α and the compact ALDAS-Mini. Technical SpecificationsMeasurement targets: electrolysis cells, fuel cells, and full stacksFrequency range: 10 mHz to 100 kHz Measurement current: up to 10 kA (with combined sensors) Multi-channel capability: 1 to 48 channels Measurement voltage: 1.5 V to 1000 V
ALDAS-Mini
ALDAS-Mini – Compact EIS Analyzer for Electrolysis Cell Development
The ALDAS-Mini is a compact, high-performance electrolysis cell analyzer designed to accelerate R&D in hydrogen production technologies. Using advanced electrochemical impedance spectroscopy (EIS), it provides deep insights into the internal behavior of electrolysis cells, enabling engineers to optimize efficiency, reduce energy losses, and improve the performance of electrolysis cells and stacks. The cell analyzer [OW1.1]can be integrated into existing test setups without modifications to the existing electrolysis system, making it ideal for flexible usage in both laboratory and industrial environments. ALDAS-Mini supports a wide range of electrolysis technologies - including PEM, SOEC, AEM, and alkaline systems, which ensures compatibility across different development platforms. A key differentiator is its ability to perform impedance measurements under real high-current operating conditions, handling electrolysis currents from a few amperes up to 2000 A. Combined with simultaneous multi-cell measurement up to 8 cells, ALDAS-Mini enables efficient comparative analysis within cell stacks, significantly improving testing throughput and enabling faster identification of performance differences and degradation effects. With high noise immunity and precise current sensing, the ALDAS-Mini delivers stable and reliable measurement results - even in demanding environments. This makes it - making it a powerful tool for advancing next-generation hydrogen technologies. The ALDAS-Mini complements the ALDAS lineup as a compact solution alongside the high-speed ALDAS-α and the high-power ALDAS-E. Technical Specifications Electrochemical impedance spectroscopy (EIS) for electrolysis cells Electrolysis current range: up to 2000 AMulti-channel measurement: up to 8 cells simultaneously Compatible with PEM, SOEC, AEM, AWE technologies High noise immunity for stable measurements
ALDAS-α
ALDAS-α – High-Speed EIS Measurement System
The ALDAS-α is a high-performance electrochemical impedance spectroscopy (EIS) system designed for analyzing fuel cells and water electrolysis. While conventional current-voltage (I-V) measurements are widely used to evaluate overall cell performance, they are limited in identifying the underlying causes of performance changes or degradation. Using EIS, the ALDAS-α enables a deeper analysis by quantitatively evaluating and separating complex electrochemical phenomena within the cell. This provides a more detailed understanding of internal processes. Thanks to its high-precision current sensing technology, the system delivers stable and accurate impedance data from very low frequencies, ensuring reliable and easy-to-interpret results. A key benefit of the ALDAS-α system is its fast measurement speed, completing scans in less than 8 minutes [OW2.1]- significantly reducing test time compared to conventional systems. With support for simultaneous multi-channel measurements up to 8 cells and up to 20 A DC output, the ALDAS-α system reduces development time considerably. The ALDAS-α is the ideal choice for high-speed, multi-channel EIS measurements in R&D environments where precision and efficiency matter most. It is one of HIOKI’s EIS measurement solutions, alongside the compact ALDAS-Mini and the high-power ALDAS-E.[OW3.1]Technical Specifications Electrochemical impedance spectroscopy (EIS) measurement system Frequency range: high to low frequency sweep (e.g. 10 kHz to 0.01 Hz) Measurement speed: approx. 7.6 minutes (multi-channel, fast mode) Multi-channel capability: up to 8 cells simultaneously DC output: up to 20 A without external booster