ALDAS-E: EIS MEASUREMENT SYSTEM

ALDAS-E is an EIS measurement system optimized for large-scale kilowatt to megawatt-class electrolyzers and fuel cells. This in-situ capability facilitates the exploration of optimal operating points and provides data-driven insights into the internal state and degradation mechanisms of the cell stack, and unlike conventional methods, it supports impedance analysis of large stacks during active demonstration and commercial operation.

Key Features

EIS measurement of kW to MW class stacks in actual operation
Simultaneous measurement of stack and cell with up to 48 channels
High-speed EIS measurement
Stable and high-precision measurement down to low frequency range
Easy connection to existing electrolyzers and FC systems

Model No. (Order Code)

EA5702

The configuration of the equipment varies depending on the number of measurement channels. For more details, please contact your authorized Hioki distributor or reseller.

EIS measurements during the actual operation of kW to MW class stacks

For large electrolysis cells where high currents flow from the rectifier to the stack in multi-wire configurations, multiple current sensors can be used in combination to measure currents up to 10 kA. This allows EIS measurements to be performed by detecting small AC signals amidst noisy DC currents while the cell is in operation.

Observe stack performance and multiple cell states simultaneously

Multi-channel measurement enables simultaneous tracking of total stack and individual cell impedance for comprehensive stack observation. This measurement system is expandable from 1 up to 48 channels.

High-speed EIS measurement shortens test cycles

To observe the diffusion resistance region, impedance measurements must be extended to the low-frequency range. However, these measurements pose a challenge as they require a significant amount of time to complete. A typical electrochemical instrument, for instance, can take roughly 30 minutes to run a scan from 10 kHz to 0.01 Hz.

The ALDAS-E completes the same measurement in approximately 7.6 minutes*¹ across 8 channels simultaneously. This advantage in speed and parallel measurement capability significantly improves throughput for evaluating electrolysis cells and fuel cell systems.
(*1:Measurement conditions: 10 kHz to 0.01 Hz, 30 points, fast mode)

Stable, high-accuracy measurement down to the low-frequency range

Our current sensor method avoids the temperature drift issues common with shunt methods. High precision current measurement ensures stable results with minimal variation, even at low frequencies below 1 Hz.

Easy connection to existing electrolysis cell and fuel cell systems

Designed specifically for EIS, ALDAS offers a simple setup that connects in parallel to existing electrolysis cells and fuel cell systems—no dedicated power supply or load required. Furthermore, our current sensors ensure easy installation without any system modifications.

Basic specification

Accuracy guaranteed: 1 year

Measurement target	Electrolysis cell, fuel cell, cell stack
Measurement parameters	Impedance (R,X,θ,Z), voltage (V), current (I)
Measurement modes	Logging Mode, EIS Mode
Measurement voltage range	1.5 V to 1000 V
Display modes	Nyquist plot, Bode plot, logging plot
Measurement current range	400 mA to 2000 A (CT6877A) Maximum 10 kA (depending on the combination of sensors)
Max. applied measurement signal	80 Ap-p (at 50 V) Derating applies for voltages above 50 V
Measurement frequency range	10 mHz to 100 kHz
Number of input channels	1 to 48 channels
Dimensions and weight	13U Rack cabinet (Z5411) : Approx. 570W × 860H × 650D mm (22.4W × 33.9H × 25.6D in.) (including casters, excluding protruding parts) Approx. 85 kg (EA5302-08 ×1, EA5502 ×1, EA5901 ×1) 19U Rack cabinet (Z5412) : Approx. 570W × 1100H × 650D mm (22.4W × 43.3H × 25.6D in.) (including casters, excluding protruding parts) Approx. 125 kg (EA5302-08 ×2, EA5502 ×2, EA5901 ×1) 24U Rack cabinet (Z5413) : Approx. 570W × 1360H × 650D mm (22.4W × 53.5H × 25.6D in.) (including casters, excluding protruding parts) Approx. 150 kg (EA5302-08 ×3, EA5502 ×2, EA5901 ×1)
Power supply	100 V to 240 V AC, 50 Hz/60 Hz 13U Rack cabinet (Z5411) : Maximum rated power 360 VA 19U Rack cabinet (Z5412) : Maximum rated power 815 VA 24U Rack cabinet (Z5413) : Maximum rated power 965 VA
PC requirements	OS: Windows 11 Interface: wired LAN