NACE Corrosion 2020 to feature a presentation by Gamry Instruments’ David Loveday This Conference dates have been updated to: June 14-18, 2020 Warminster, PA, October 14, 2019 – NACE Corrosion 2020, the world’s largest conference and exposition on corrosion, is being held March 15-19, 2020 at the George R. Brown Convention Center in Houston, TX. Read more about Gamry Instruments’ Presentation at NACE CORROSION 2020 Conference dates have been updated to June 14-18, 2020[…]
When: November 11-12, 2019 Where: Windsor Suites 1700 Benjamin Franklin Parkway Philadelphia, PA (USA) Gamry Instruments is proud to once again co-sponsor the EIS (Electrochemical Impedance Spectroscopy) Short Course being held November 11th-12th at the Windsor Suites, 1700 Benjamin Franklin Parkway, Philadelphia, PA (USA). This year the two-day, hands-on course is designed for researchers who are Read more about A New Two-Day Hands-on EIS Short Course Philadelphia[…]
Gamry Instruments has taken one of their most popular Application Notes, The Basics of Electrochemical Impedance Spectroscopy, and revised it into a new easy-to-read resource for researchers, academics and professionals. This newly designed reference guide is a primer on EIS and includes descriptions, formulas, and data presentations to get you started on building your knowledge Read more about Basics of Electrochemical Impedance Spectroscopy[…]
Batteries are indispensable energy storage systems for mobile and stationary applications. They are mostly used for portable devices or when electrical lines are impractical or impossible.
Their application fields reach from smaller devices such as MP3 players or smartphones up to high power systems for the […]
A new partnership between Bitrode and Gamry was announced today. The collaboration in the development of battery test equipment shows the strength of the two companies. A ‘One Stop‘ product has been created by integrating Gamry’s EIS […]
Gamry is pleased to once again be presenting a webinar sponsored by PlugVolt. This year’s webinar entitled: “Electrochemical Impedance Spectroscopy and Its Application to Battery Analysis” will be presented by Chris Beasley of Gamry Instruments. When: Wednesday February 17, 2016 What Time: 10:00 a.m. EDT USA / 4:00 p.m. CET Europe / 10:00 p.m. China Read more about Gamry Hosted Webinar: EIS and Its Application to Battery Analysis[…]
Converting chemical energy into electrical energy can be done in different ways, but for chemical energy stored in various fuels like hydrogen, electrochemical fuel cells are the most direct, and have the potential to be very efficient.
The electrochemistry side of fuel cells is rather straightforward. Hydrogen, possibly with some carbon, on one side combines with oxygen on the other to produce water and possibly carbon dioxide. The half reactions are separated so that the energy difference between reagents and products can be harvested as electrical energy.
Electrochemical Impedance Spectroscopy can identify problems that limit a fuel cell’s efficiency, by helping to optimize a cell, it can determine anodic and cathodic process mechanisms. EIS is particularly good for measuring the equivalent series resistance of fuel cells, a major source of power loss in a low impedance device. Because of the modeling capability of EIS, you can also extract information on kinetics and mass transport in the fuel cell, both of which are crucial factors to fuel cell performance. EIS is useful in both research and QC applications. EIS of fuel cells runs into some of the same low impedance device and setup limitations that also show up in batteries and supercapacitors.
Gamry will be holding a Workshop at the ECS Meeting in Cancun, Mexico. If you do EIS on very low impedance or very high impedance samples then you should attend Gamry’s workshop at the ECS meeting tomorrow. This workshop will cover precautions needed for analyzing very low impedance samples such as batteries and fuel cells as Read more about Electrochemical Impedance Spectroscopy of Difficult Samples[…]
The 26th Annual Fall EIS Short Course:
Electrochemical Impedance Spectroscopy:
Theory – Applications – Laboratory Instruction
Dates: November 10-14, 2014
Where: Houston, Tx
Impedance spectroscopy is an extremely powerful non-destructive investigative technique that can obtain essential information about interfacial and bulk material parameters through the use of low energy, time varying electrical excitation. When applied to an electrochemical system, electrochemical impedance spectroscopy (EIS) can provide information on reaction parameters, corrosion rates, oxide characteristics and integrity, surface porosity, coating integrity, mass transport, and many other electrode/interface characteristics. EIS is possibly one of the most powerful methods available in electrochemistry today and is utilized in research and development in essentially every technical sector, e.g., transportation and infrastructure, batteries and fuel cells, medicine, among many others. However, effective utilization of this method has been hindered by the lack of a comprehensive and cohesive explanation of the theory, measurement, and analysis techniques. This course on EIS has been developed to fill this void.
This short course, now in its 26th year, was first taught in 1988 in Charlottesville, Virginia. It has recently had the tremendous fortune of moving to the vibrant and technologically rich city of Houston, Texas. Please read more about our course on this website, or contact us either by e-mail or telephone.
Course Objective […]
This application note presents an introduction to Electrochemical Impedance Spectroscopy (EIS) theory and has been kept as free from mathematics and electrical theory as possible. If you still find the material presented here difficult to understand, don’t stop reading. You will get useful information from this application note, even if you don’t follow all of the discussions.
Four major topics are covered in this Application Note.
- AC Circuit Theory and Representation of Complex Impedance Values
- Physical Electrochemistry and Circuit Elements
- Common Equivalent Circuit Models
- Extracting Model Parameters from Impedance Data
No prior knowledge of electrical circuit theory or electrochemistry is assumed. Each topic starts out at a quite elementary level, then proceeds to cover more advanced material.
AC Circuit Theory and Representation of Complex Impedance Values
Impedance Definition: Concept of Complex Impedance
Almost everyone knows about the concept of electrical resistance. It is the ability of a circuit element to resist the flow of electrical current. Ohm’s law (Equation 1) defines resistance in terms of the ratio between voltage, E, and current, I.
While this is a well known relationship, its use is limited to only one circuit element — the ideal resistor. An ideal resistor has several simplifying properties:
- It follows Ohm’s Law at all current and voltage levels.
- Its resistance value is independent of frequency. AC current and voltage signals though a resistor are in phase with each other.
“Although the equivalent circuit approach is looked down upon by some, analyzing EIS data by fitting it to equivalent circuit models can be a valid and rewarding approach, particularly in the early stages of an investigation.” When you first begin an electrochemical investigation, very often you may know little or nothing about the process or Read more about Fitting EIS Data to Equivalent Circuits[…]