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Membrane Electrode Assembly (MEA) Activation Procedures
  Why is an activation procedure or break-in necessary for a membrane electrode assembly (MEA)? A large reason for performing an activation procedure or break-in is to properly humidify the membrane portion of the MEA that was dried out during the hot press stage of the membrane electrode assembly (MEA) production. MEAs will not work well when they are not fully humidified (see article: Why is Humidity / Moisture Control Important in a Fuel Cell?). How do I Humidify a Membrane Electrode Assembly (MEA)? You can re-humidify the MEA by soaking it in deionized water. ..
How Ion Exchange Works
In nature, the majority of gases, liquids, and solids are not charged (in the neutral form). Ion exchange, where free ions are exchanged for different ions, occurs when there is an open network structure to carry the ions through it. There are many natural and man-made mediums that are ion exchangers, including solids, liquids, and gases. The medium needs to be in contact with the ion exchanger and these two entities exchange some of its ions for similarly charged ions. The medium is often a solid ion exchanger in contact with an aqueous solution or gas. If you recall from chemistry, there ..
Membrane Properties and Characterization for Zero-Gap CO2 Electrolyzers
Zero-gap electrolyzers are similar to fuel cells in design because the heart of the electrolyzer consists of two electrodes pressed against a membrane. These electrolyzers are called “zero-gap” because there is no gap between the cathodes, anodes, and the electrolyte. This design decreases the distance for ion transport because the layers are pressed or bonded together. The zero-gap CO2 electrolyzers can achieve high current densities (≥100 mA/cm2) by delivering gaseous CO2 to the cathode. The efficiency of these electrolyzers depends upon the catalysts used, the operating conditions, and o..
Compact Transient Model for Nafion Membranes

A numerical model was developed to predict the water concentration, temperature, potential and pressure across a Nafion membrane used in proton exchange membrane (PEM) based fuel cells. The numerical model consists of simultaneously calculating the diffusive flux for water and hydrogen, the proton potential and the pressure and temperature at each node...

An Introduction to Ion Exchange Membranes and Salt Splitting

Ion-exchanges membranes (IEMs) have many applications beyond fuel cells -- they can also be used to synthesize all types of compounds that are used in various industries. The most popular IEMs consist of polymeric resins with charged functional groups based upon their ion selectivity, they are referred to as anion-exchange (AEM) and...

Anion Exchange Membranes (AEMs)

Anion exchange membranes (AEMS) have been an active area of research for over a decade. AEMS can be used for fuel cells, redox flow batteries, electrolyzers, and even water desalination membranes. The electrolyte layer is the “heart” of electrochemical cells such as fuel cells, batteries, and because it transports ions from...

A One-Dimensional Heat, Mass and Charge Transfer Model for a Polymer Electrolyte Fuel Cell Stack

A one-dimensional heat, mass and charge transfer model was developed for a polymer electrolyte fuel cell stack to predict the temperatures, mass flows, pressure drops, and charge transport of each fuel cell layer over different operating conditions. The fuel cell layers’ boundaries were...

A Review of Mathematical Modeling of Proton Exchange Membrane and Direct Methanol Fuel Cells

There has been a lot of emphasis on the development of long-lasting, efficient and portable, power sources for further technology improvement in commercial electronics devices, medical diagnostic equipment, mobile communication and military applications. These systems all require...

Building a Micro DMFC Design

This blog post includes a quick fuel cell introduction, parts list and design for a 1 cm x 1 cm (active area) fuel cell. This summary was put together mainly for students interested in fuel cell research. Figure 1 presents a summary of the dimensions and basic characteristics of most MEMs fuel cell stacks in the...

Fuel Cell Modeling Basics

Fuel cell modeling is helpful for fuel cell developers because it can lead to fuel cell design improvements, as well as cheaper, better, and more efficient fuel cells. The model must be robust and accurate and be able to provide solutions to fuel cell problems quickly. A good model should predict fuel cell performance under a wide range of...

Transport Phenomena in Micro and MEMs Fuel Cells

As fuel cell size decreases, the transport phenomena of the fuels and water changes in the fuel cell. In standard fuel cell designs, the movement of fuel and water is governed by volumetric effects, but surface effects become critical as dimensions shrink. A good rule of thumb is that millimeter-scale devices are small enough for...

Fuel Cell Electrolyte Layer Modeling

The electrolyte layer is essential for a fuel cell to work properly. In PEM fuel cells (PEMFCs), the fuel travels to the catalyst layer and gets broken into protons (H+) and electrons. The electrons travel to the external circuit to power the load, and the hydrogen protons travel through the electrolyte until it reaches the cathode to combine with oxygen to form...

Processing Alternative Fuels for Fuel Cells

Fuel cells are not limited to pure hydrogen gas as fuel. Each type of fuel cell stack has different fuel tolerances. The lower the operating temperature of the stack, the stricter the requirements for pure fuel. For fuels other than pure hydrogen, an external fuel processing system may...

Chemical Hydrides

Fuel cells often use compressed hydrogen as the fuel; however, many other hydrogen sources can be used with fuel cells. Chemical hydride storage is an alternative method of producing hydrogen via a chemical reaction. These reactions involve chemical hydrides, water, and alcohols. The chemical reactions are not reversible, and the byproducts must be discarded. Hydrogen fuel can also...

Metal Hydrides

Fuel cells usually use compressed hydrogen as the fuel, but there are many other types of fuels that can be used. The type of fuel used depends upon the fuel cell application. Fuels are often in their final form before entering the fuel cell; however, certain fuel cell types can be processed on the inside of the fuel cell. Alternative fuel types are...