Potentiostats / Galvanostats

Potentiostats and Galvanostats – Professionally Enhanced

Potentiostats and galvanostats are essential electrochemical instruments widely used in scientific and industrial research to control and measure electrical parameters within electrochemical systems. These instruments are often integrated into a single platform, allowing for a seamless transition between potentiostatic (voltage-controlled) and galvanostatic (current-controlled) modes, depending on the experimental objective. This dual functionality is critical for applications such as corrosion testing, battery development, electrocatalysis, and sensor fabrication.

What Are Potentiostats and Galvanostats?

Potentiostats

A potentiostat is a precision analytical instrument used to maintain a specified electrode potential at the working electrode relative to a reference electrode within a multi-electrode electrochemical cell, typically comprising working, reference, and counter electrodes. It regulates the potential by dynamically adjusting the current between the working and counter electrodes. This enables accurate investigation of redox reactions, corrosion resistance, electroplating kinetics, battery performance, and the operation of electrochemical sensors.

Internally, potentiostats use operational amplifier-based feedback circuits to maintain the set potential regardless of changes in cell resistance. Experimental data are generally recorded as current vs. potential (e.g., cyclic voltammetry) or current vs. time (e.g., chronoamperometry or bulk electrolysis), offering valuable insights into electron transfer mechanisms and mass transport phenomena.

Galvanostats

A galvanostat, also called an amperostat, maintains a constant current through the electrochemical cell regardless of resistance fluctuations. In contrast to the potentiostat, which holds the voltage constant, the galvanostat modulates the voltage output to sustain a fixed current, measuring the resulting cell potential in real time.

Following Ohm’s law, the galvanostat adjusts the applied voltage according to changes in load resistance. This control method is indispensable for electrolysis, battery cycling, electrodeposition, and constant-current impedance spectroscopy.

Modes of Operation and Applications

Potentiostatic mode is ideal for:

• Studying redox reactions, corrosion mechanisms, and electroplating behaviour.
• Techniques such as cyclic voltammetry (CV) with linear or sweep voltages.
• Investigating reaction kinetics, surface modifications, and charge transfer processes.

Galvanostatic mode is suited for:

• Electrolysis and thin-film deposition studies.
• Charge-discharge cycles in lithium-ion batteries and fuel cells.
• Electrochemical impedance spectroscopy (EIS) at constant current and low-impedance system evaluation.

Product Families and Features

Squidstat Potentiostats / Galvanostats

User-friendly, modern instruments designed for flexible electrochemical testing with strong value propositions for academic and industrial users.

• Squidstat Plus
• Squidstat Prime
• Squidstat Solo
• Squidstat Penta
• Squidstat Decka
• Squidstat Venta

Zennium Modular Potentiostats / Galvanostats

High-performance modular platforms developed with decades of expertise in electrochemical impedance spectroscopy (EIS), allowing for advanced configuration and customisation.

• Zennium XC
• Zennium PRO
• Zennium X

External Power Potentiostats

Four-quadrant external potentiostats extend the current and voltage capabilities of Zennium PRO or Zennium X, enabling high-demand experiments.

• PP212
• PP222
• PP242
• XPOT2
• Electronic Load – EL1002

Optional Addon Cards / Modules

Accessory modules are designed to expand functionality for advanced applications in kinetic modelling and complex system simulation.

• PAD4 card

CorrTest Single Channel Potentiostats / Galvanostats

High-speed digital platforms delivering robust data acquisition, stable output, and accurate analysis in corrosion science and fundamental electrochemistry.

• CS350M
• CS310M
• CS300M
• CS100E (with EIS) – Portable potentiostat
• CS100 (without EIS) – Portable potentiostat

CorrTest BiPotentiostats / BiGalvanostats

CorrTest bipotentiostat and bigalvanostat are advanced electrochemical instruments designed for dual-channel and high-current applications. The bipotentiostats enable simultaneous control of two working electrodes, ideal for electrocatalysis, redox comparisons, and EIS-based sensor studies. Bigalvanostats deliver stable, multi-channel current control for battery testing, electroplating, and fuel cell evaluation in high-demand research environments.

• CS2350M Bipotentiostat (2-channel, 2-EIS)
• CS2150M Bipotentiostat (2-channel, No EIS)

CorrTest Multichannel Potentiostats / Galvanostats

Multi-channel configurations for parallel testing, ideal for battery arrays, corrosion screening, and multi-electrode experimentation.

• CS310X-A (4-Ch, 1-EIS)
• CS310X-B (4-Ch, 4-EIS)
• CS310X-C (8-Ch, 1-EIS)
• CS310X-D (8-Ch, 8-EIS)

CorrTest Current Boosters and Specialized Devices

High-current booster modules and specialized systems for pitting corrosion analysis and electrochemical mapping.

• 20A/40A/100A Current Booster
• CS300M for pitting corrosion
• CST520 Multi-electrode Array Electrochemical Mapper

Summary

ScienceGears offers robust potentiostat and galvanostat solutions for a wide spectrum of electrochemical applications. From compact benchtop units to modular high-performance systems, the Squidstat, Zennium, and CorrTest series empower researchers with precise control, reproducibility, and seamless integration across diverse domains such as corrosion engineering, lithium-ion and sodium-ion battery research, fuel cell development, electrocatalysis, electroplating, supercapacitor characterization, water splitting, biosensing, and electrochemical impedance spectroscopy (EIS). Backed by advanced software, scalable configurations, and specialized expansion modules, our platforms are engineered to support cutting-edge scientific workflows with long-term reliability and flexibility.

 

FAQs

1. What is a Potentiostat
A potentiostat is an electronic instrument used in electrochemical research to control the voltage between a working electrode and a reference electrode, while simultaneously measuring the current flowing to or from the working electrode. It plays a central role in techniques like cyclic voltammetry, chronoamperometry, and electrochemical impedance spectroscopy (EIS).

Potentiostats are essential for studying redox reactions, energy storage devices, corrosion, electrocatalysis and electrochemical sensors. By maintaining a constant potential and measuring the resulting current, researchers can analyse electron transfer kinetics, diffusion processes, and material properties at the electrode–electrolyte interface.

It uses three electrodes:

Working Electrode (WE): Where the chemical reaction happens.
Reference Electrode (RE): A stable point to compare voltage.
Counter Electrode (CE): Completes the circuit.

2. How does a potentiostat work?
A potentiostat is an electronic device widely used in electrochemistry to precisely control and maintain the voltage (potential) of a working electrode relative to a stable reference electrode and measure the corresponding current flowing through the system.

Here’s a clear and simplified explanation of its working principle:

Key Components of a Potentiostat:

A typical potentiostat involves a three-electrode system:

• Working Electrode (WE): The electrode at which the electrochemical reaction of interest occurs.
• Reference Electrode (RE): An electrode with a stable and known potential, used as a fixed reference point.
• Counter Electrode (CE) / Auxiliary Electrode: Completes the circuit by balancing the current passing through the working electrode.

Working Principle (Step-by-Step):

Potential Control

• The potentiostat applies a controlled voltage between the Working Electrode and the Reference Electrode.
• The Reference Electrode provides a stable, known reference potential, ensuring accurate control and measurement.

Current Measurement

• Once the set potential is applied, the electrochemical reaction occurs at the Working Electrode, causing electrons to flow.
• This electron flow (current) moves through the electrolyte and completes the circuit via the Counter Electrode.
• The potentiostat precisely measures the current resulting from this reaction.

Feedback Control

• The potentiostat uses an operational amplifier (op-amp) and feedback loops to accurately maintain the desired potential at the Working Electrode, continually adjusting as the reaction proceeds.
• This feedback mechanism rapidly compensates for changes in the reaction environment, ensuring constant potential.
  
  

3. What is the difference between a potentiostat and a galvanostat?
The primary difference lies in the control variable: a potentiostat controls the voltage and measures the resulting current response, while a galvanostat controls the current and measures the resulting voltage.

Potentiostatic control is often used to probe reaction kinetics and mechanisms, whereas galvanostatic control is commonly employed in applications such as battery charge/discharge, electroplating, and corrosion rate measurements. Many modern instruments can switch between these modes to suit different experimental needs.

Potentiostat vs. Galvanostat: Key Differences

Feature / Aspect	Potentiostat	Galvanostat
Primary Control	Voltage (potential)	Current
Measured Output	Current	Voltage
Control Mechanism	Maintains constant voltage between WE and RE	Maintains constant current through the cell
Main Use Cases	Redox studies, corrosion, EIS, CV, electrochemical sensors	Battery cycling, electroplating, corrosion under fixed current
Electrode Setup	Three-electrode system (WE, RE, CE)	Three-electrode system (WE, RE, CE)
Response to Cell Changes	Adjusts the current to maintain voltage	Adjusts voltage to maintain current
Example Techniques	Cyclic voltammetry, chronoamperometry, EIS	Galvanostatic charge/discharge, LSV with constant current
Common in	Research labs, sensor development, surface chemistry	Battery labs, corrosion testing, material stress studies
Feedback Loop Goal	Keep WE at the desired potential	Keep current through the WE constant
When to Use	When understanding electrochemical reaction mechanisms	When applying a specific current load is critical

 

4. What is a floating mode potentiostat?
A floating mode potentiostat is an instrument designed to operate independently of earth ground, meaning its internal circuitry is electrically isolated from the mains ground. This allows the potentiostat to safely perform measurements on electrochemical systems that are not grounded themselves, such as batteries in series, fuel cell stacks, solar panels, or cells housed within metallic autoclaves.

Operating in floating mode eliminates the risk of ground loops, which can introduce noise, cause erroneous data, or even damage the equipment. Ground loops occur when multiple paths to ground create unintended current flow through sensitive measurement circuits.

Floating potentiostats are especially useful in hydrogen permeation experiments, where the electrochemical cell is often placed inside a metallic pressure vessel or connected to high-impedance gas detection systems. In such setups, direct grounding could lead to short circuits or interfere with signal integrity. The floating configuration allows accurate measurement of transient hydrogen diffusion signals without interference from the metallic housing or other grounded lab equipment.

Other common use cases include:

• Testing individual cells within high-voltage battery stacks
• Electrochemical monitoring inside metal reactors
• Electrochemistry on grounded substrates (e.g., metal sheets or pipelines)

In short, a floating potentiostat provides electrical safety, signal stability, and versatility in complex or grounded environments.

5. What is a bipotentiostat?
A bipotentiostat is a specialised potentiostat that can control two working electrodes independently but with respect to the same reference and counter electrode. It is commonly used in studies involving dual-electrode systems, such as generator-collector configurations, electrochemical sensors, or RRDE experiments.

This enables the simultaneous monitoring of two related reactions, allowing for mechanistic studies with high temporal resolution.

6. What is the purpose of a reference electrode?
The reference electrode provides a stable, known potential against which the voltage of the working electrode is measured and controlled. Unlike the counter electrode, it does not carry current, ensuring that the potential remains constant throughout the experiment.

Common reference electrodes include Ag/AgCl, saturated calomel electrode (SCE), and Hg/HgO, each selected based on the solvent and experimental needs. A stable reference is critical for reproducibility and accurate interpretation of electrochemical results.

7. What is the function of a counter electrode?
The counter electrode (also called the auxiliary electrode) completes the circuit by allowing current to flow through the electrochemical cell. It is typically made from inert materials like platinum or carbon, which do not participate in the electrochemical reaction of interest.

Its primary role is to balance the current passing through the working electrode, ensuring that the potentiostat can maintain the desired potential at the working electrode.

8. How do I choose the right potentiostat?
To select the right potentiostat, consider the voltage range, current range, EIS capability, number of channels, and sampling rate in relation to your specific application. For example, battery and corrosion studies may require higher currents, while sensor research may focus on low-noise performance and sensitivity.

Also evaluate software usability, data export formats, and instrument expandability. If you plan to scale your research, opt for modular or multi-channel models.

9. Is a built-in EIS necessary?
If your work involves impedance characterisation of batteries, coatings, sensors, or fuel cells, built-in EIS is highly beneficial. It enables frequency sweeps from mHz to MHz without external modules.

For users not working with impedance, EIS may be optional, but is often a worthwhile future-proof feature.

10. What is a dummy cell?
A dummy cell is a test circuit composed of resistors, capacitors, or diodes that simulate predictable electrochemical behaviour. It’s used to validate potentiostat performance, calibrate EIS, and troubleshoot noise or instability.

Dummy cells are essential tools for training and diagnostics.