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This poster presents some practical tips to make your daily work with the NOVA software easier.

This poster summarizes how to optimize NOVA procedures in 6 easy steps.

Non-enzymatic ethanol sensor based on a nanostructured disposable screen-printed electrode.

Automatic sample handling and analysis is very convenient for routine measurements on large number of samples. Metrohm offers a wide range of high performance liquid handling devices that can be combined with the Autolab product range and can be directly controlled by the NOVA software.

The Metrohm 800 Dosino is the workhorse of any automated liquid handling setup. This instrument can be conveniently used in combination with the NOVA software and integrated conveniently with electrochemical measurements performed with the Autolab systems.

The Metrohm 858 Professional Sample Processor is a robotic liquid handling system capable of handling large series of samples automatically. This instrument provides a platform that can be directly controlled by the NOVA software and combined with the Autolab potentiostat/galvanostat for automated high-throughput electrochemical measurements.

A nickel metal hydride battery, abbreviated NiMH, is a type of rechargeable battery similar to a nickel-cadmium (NiCd) battery but, for the anode, instead of cadmium, it has a hydrogen absorbing alloy. Like in NiCd batteries, nickel is the cathode. The voltage output of such packs is directly proportional to the number of single cells in the pack. In some cases, the total voltage can exceed the maximum of 10 V that is measurable by the Autolab potentiostat/galvanostat. To apply and measure voltages greater than 10 V, we have developed a voltage multiplier that increases the voltage range of the Autolab.

Lithium-ion (Li-ion) batteries are one of the most important energy storage devices in the market. A typical Li-ion battery is usually composed of one or more cells. Characterization of Li-ion cells and batteries usually involves the galvanostatic charge and discharge during various cycles.

This Application Note shows how AUTOLAB and NOVA is used to perform GITT tests on a Li-ion battery. Here,galvanostatic charge pulses are applied, each followed by relaxation time, until the upper potential limit is reached. Then, discharge pulses are applied, followed by equilibration time, until the lower potential limit is reached. From the potential vs. time plot, important information for calculating the diffusion coefficient and thermodynamics parameters quantities can be obtained.

During charge and discharge of a Li-ion battery, lithium ions are transported from one electrode through the electrolyte to the other electrode. Knowing the chemical diffusion coefficient of electrode materials is crucial. The potentiostatic intermittent titration technique (PITT) is one of the most used techniques to retrieve insights on the diffusion coefficient of the electrode active materials.

The main components of a battery are the positive and negative electrodes, together with the electrolyte, which provides only the ionic conductivity. The most common electrolytes are in the liquid state. Therefore, a separator is needed to provide a physical separation between the electrodes. The separator is soaked with electrolyte. The MacMullin number is a parameter used to determine the quality of a separator, in terms of ionic conductivity, when soaked with an electrolyte. The MacMullin number can be calculated, using the results of data fitting of two EIS experiments and the geometric factors of the measurement cells. In this application note, a commercial electrolyte is employed, together with a porous filter, used as a separator.

The TSC SW closed and TSC battery cells are compact systems designed for measurement of air or moisture sensitive materials, such as those materials used in rechargeable batteries. These cells offer well-controlled environment for the in-temperature measurement of solid and gel like materials in contact with metal electrodes in planar geometry. For example, battery active materials, ionically conductive solid-state electrolytes and battery separators can be tested using these cells. In this experiment, standard resistors of 100 Ω are used in both cells to understand the cell effects, if any, on the measurements.

The DuoCoin Cell Holder is introduced. EIS measurements on a commercial coin cell battery are performed. Differences in impedance between the four-terminal configuration and two-terminal configuration is highlighted, putting in evidence the importance of having a direct four-terminal configuration, when low-impedance DUTs are investigated.

In this application note, we demonstrate how to determine the binary diffusion coefficient of a commercial liquid binary lithium ion battery electrolyte based on a galvanostatic pulse polarization method.

This application note presents the experimental details and an overview of the most important findings from the EIS and CV experiment to study the structure of a model solid electrolyte interface forming on a planar glassy carbon electrode in contact with a typical organic battery electrolyte.

In this application note, we demonstrate how to determine the through-plane tortuosity τ of a commercial lithium ion battery cathode material with known porosity and coating thickness, based on the electrochemical impedance spectroscopy (EIS) method.

In this application note, we demonstrate how to determine the lithium ion transference number of a commercial liquid binary lithium ion battery electrolyte, based on the very-low-frequency electrochemical impedance spectroscopy (VLF-EIS) method.

In battery research, electrochemical impedance spectroscopy (EIS) is a necessary tool to investigate the processes occurring at the electrodes. With a common three-electrode battery, EIS can be performed sequentially first at one electrode and then at the other electrode.

This Application Note explains how researchers can determine the underlying chemistry and potential failure mechanisms from cycle testing batteries with INTELLO.

This Application Note discusses differential capacity analysis (DCA) and its impact on enhancing battery performance, with a focus on using the INTELLO platform.

Corrosion refers to a process that involves deterioration or degradation of metal. The most common example of corrosion is the formation of rust on steel. Most corrosion phenomena are of electrochemical nature and consist of at least two reactions on the surface of the corroding metal.

Electrochemical methods provide an alternative to traditional methods used to determine the rate of corrosion. For example, corrosion rates, the rates at which a specimen corrodes, can be calculated from simple electrochemical measurements like a linear sweep voltammetry (LSV).

In real life, often, corrosion is a result of several reactions and it is not possible to determine a priori the reaction mechanism. In such cases, the polarization resistance can be used to determine the resistance of the metal under investigation against corrosion.

Electrochemical impedance spectroscopy or EIS has been used effectively to measure the polarization resistance for corrosion systems and for the determination of corrosion mechanisms.

A corrosion inhibitor is a substance that reduces the corrosion rate of a metal. A corrosion inhibitor is usually added in a small concentration to the corrosive environment. This application note shows how Metrohm Autolab instruments can be used to check the quality of inhibitors.

This Application Note is based on the ASTM standard G150, developed to test the resistance of stainless steel, and otheralloys related to stainless steel, on pitting formation at elevated temperature. This is achieved by determining the potential-independent critical pitting temperature (CPT), defined as the lowest temperature at which pitting evolution occurs. The CPT experiment consists of applying a potential to the specimen while the cell temperature is raised and recording the current.

In this Application Note, stepwise dissolution measurement (SDM) is applied to aluminum samples coated with different materials, in order to gain insights in corrosion protection. The combination of the Autolab PGSTAT204 with the 1 L Autolab corrosion cell and the NOVA software provides the suitable setup to perform SDM and other corrosion experiments.

In this Application Note, EIS is applied on three coated aluminium samples, before and after the stepwise dissolution measurement (SDM). This technique has been reviewed in the Application Note AN-COR-08.

Corrosion of metals is a problem seriously affecting not only many industrial sectors, but also private life, resulting in enormous costs. In this application note, the results gained during electrochemical corrosion studies on different metals are compared to literature data.

The ASTM standard G100 is an electrochemical method to test localized corrosion of aluminum 3003-H14 and other alloys. A cyclic galvanostatic staircase polarization (galvanostaircase) is composed of an upward and a downward scan. The potential values at the end of each step are collected and linearly fitted, and the potential values at zero current are found.

The ASTM standard G5 is a method to test the corrosion of Type 430 stainless steel, with a potentiodynamic anodic polarization measurement. The ASTM standard G5 for testing the corrosion of stainless steel 430 in sulfuric acid solution has been implemented in a NOVA procedure and the experiment performed with a PGSTAT302N and a 1 L corrosion cell.

The rotating cylinder electrode (RCE) is a technique used in corrosion research to simulate in a laboratory environment the turbulent flow which usually occurs when liquids are transported through pipelines. The RCE is used to generate a turbulent flow at the surface of a sample, simulating the pipe flow conditions. Experiments that involve an RCE are regulated by the ASTM G185 standard. In this application note, The RCE with a 1018 carbon steel cylinder sample was used with the linear polarization (LP) measurement technique.

The rotating cylinder electrode (RCE) is successfully used in a laboratory environment to generate a turbulent flow at the surface of a sample, simulating realistic pipe flow conditions. In this application note, the corrosion rate is measured and compared between quiescent and turbulent flow conditions, while keeping all the other experimental conditions unchanged. The linear polarization (LP) technique was used together with the RCE (with and without rotation).

The ASTM standard G61 is used to determine the susceptibility to localize corrosion on various alloys of iron, nickel and cobalt, in a chlorine environment. This application notes shows a measurement example in accordance with the ASTM G61 by using a Metrohm Autolab PGSTAT302N and a Metrohm Autolab 1 L corrosion cell.

The International Standard ISO 17463 describes the determination of the anticorrosive properties of high impedance organic protective coatings on metals. This technique uses cycles composed of electrochemical impedance spectroscopy (EIS) measurements, cathodic polarizations and potential relaxation. This application note shows the compliance of the Metrohm Autolab PGSTAT M204 and flat cell with the standard ISO 17463.

Tafel analysis is an important electrochemical technique used to understand reaction kinetics. By studying the Tafel slope, it reveals the rate-determining steps in electrode reactions, aiding fields like corrosion and fuel cell research. This method helps industries optimize processes and improve device performance by tailoring materials and conditions for greater efficiency.

Electrochemistry, spectroscopy, and spectroelectrochemistry (SEC) are widely used techniques in many fields. However, the data curves obtained from these analyses are quite varied, and not all electrochemical peaks and spectroscopic bands can be measured with the same procedures. This Application Note examines four tools included in the DropView 8400 and DropView SPELEC softwares to facilitate the measurement and analysis of the collected curves and data. The following measurement options are explained in detail: automeasurement, set on curve measurement, set free measurement, and set step measurement.

The mass transport characteristics of the diffusion controlled oxidation and reduction of the ferri/ferro cyanide couple was studied using the Autolab RDE with a low noise liquid Hg contact.

A reference electrode has a stable and well-defined electrochemical potential (at constant temperature), against which the applied or measured potentials in an electrochemical cell are referred. A good reference electrode is therefore stable and non-polarizable. In other words, the potential of such an electrode will remain stable in the used environment and also upon the passage of a small current. This application note lists the most used reference electrodes, together with their range of use.

When current flows through an electrochemical cell, a potential drop between the RE and the WE occurs. This voltage drop is influenced by the electrolyte conductivity, the distance between the reference and the working electrodes, and the magnitude of the current. This application note gives a basic explanation of the Ohmic drop, its causes and the impact on measurements.

This application note describes three different measurement methods of the ohmic drop and the ohmic resistance presented. Current interrupt and positive feedback are fast methods, but care is necessary for their use in order to avoid data misinterpretation or damage to the setup. EIS, on the other hand, is a more reliable method to determine the ohmic resistance. The ohmic drop can be compensated by the potentiostat during the measurement, or a mathematical correction can be applied to the data.

The Autolab Electrochemical Quartz Crystal Microbalance (EQCM) is an optional module for the Autolab PGSTAT which can be used to control a 6 MHz crystal oscillator. This technique can be used to perform electrogravimetric measurements with detection limits in the sub μg range.

This document describes a very simple procedure that can be used to produce small deposits of platinum on a goldsubstrate. This simple procedure is based on an electrochemical process known as displacement deposition, during which the deposition of a noble metal occurs by the oxidation of a precursor metal adlayer deposited on the substrate, at open circuit potential (OCP).

In this Application Note, analog and digital staircase potential signals are applied to a platinum working electrode in an acidic solution. The differences in measured currents are highlighted and compared with a similar experiment where the current is being calculated from the measured charge.

A basic overview of the working principle of a potentiostat/galvanostat is presented. Depending on the application, the connections of the instrument to the electrochemical cell can be (or must be) set up in different ways. Below, the three commonly used electrochemical cell setups are discussed together with the role of the electrodes used in electrochemical measurements.

In this application note, the combination between electrochemistry and spectroscopy is shown, with the oxidation of ferrocyanide to ferricyanide monitored with IR spectra taken at defined potential steps. The increase in absorbance at 425 nm corresponding to the formation ferricyanide.

To improve the performance of electrochemical energy storage devices like batteries and supercapacitors, one can focus on enhancing the ion conductivity (ƠDC) of the electrolyte. It is a common method for obtaining ƠDC values of different electrolyte systems, to carry out electrochemical impedance spectroscopy (EIS) experiments, at different temperatures, in a 2-electrode setup.

Copper is arguably one of the most technologically relevant metals, especially for the semiconductor industry. The deposition process used in this industry is known as the dual-damascene process and it involves the electrodeposition of copper from an acidic cupric compound, in the presence of additives.This Application Note illustrates the use of the Autolab rotating ring disc electrode (RRDE) for the study of electrodeposition of copper and the detection of the Cu+ intermediate.

The relative permittivity εr, also known as dielectric constant, is of great importance in materials characterization. It can be defined as the ratio between the amount of electrical energy stored in a material and the amount of electrical energy stored in a vacuum. One of the easiest way to obtain the relative permittivity is to calculate it from capacitance values. In this Application Note, five techniques to retrieve capacity values have been compared.

In this application note, electrochemical impedance spectroscopy (EIS) is used to test a commercial battery connected in two different ways. In the first EIS measurement, the battery is connected in a two-terminal sensing configuration. In the second EIS measurement, the battery is connected in a four-terminal sensing (Kelvin sensing) configuration. The difference in how the leads are connected results in different measured impedance values for the battery.