Next Generation Bipolar Plates For Automotive Pem Fuel Cells

The results of a successful U.S. Department of Energy (DoE) funded two-year $2.9 MM program lead by GrafTech International Inc. (GrafTech) are reported and summarized. The program goal was to develop the next generation of high temperature proton exchange membrane (PEM) fuel cell bipolar plates for use in transportation fuel cell applications operating at temperatures up to 120 °C. The bipolar plate composite developed during the program is based on GrafTech's GRAFCELL resin impregnated flexible graphite technology and makes use of a high temperature Huntsman Advanced Materials resin system which extends the upper use temperature of the composite to the DoE target. High temperature performance of the new composite is achieved with the added benefit of improvements in strength, modulus, and dimensional stability over the incumbent resin systems. Other physical properties, including thermal and electrical conductivity of the new composite are identical to or not adversely affected by the new resin system. Using the new bipolar plate composite system, machined plates were fabricated and tested in high temperature single-cell fuel cells operating at 120 °C for over 1100 hours by Case Western Reserve University. Final verification of performance was done on embossed full-size plates which were fabricated and glued into bipolar plates by GrafTech. Stack testing was done on a 10-cell full-sized stack under a simulated drive cycle protocol by Ballard Power Systems. Freeze-thaw performance was conducted by Ballard on a separate 5-cell stack and shown to be within specification. A third stack was assembled and shipped to Argonne National Laboratory for independent performance verification. Manufacturing cost estimate for the production of the new bipolar plate composite at current and high volume production scenarios was performed by Directed Technologies Inc. (DTI). The production cost estimates were consistent with previous DoE cost estimates performed by DTI for the DoE on metal plates. The final result of DTI's analysis for the high volume manufacturing scenario ($6.85 /kW) came in slightly above the DoE target of $3 to $5/kW. This estimate was derived using a "Best Case Scenario" for many of the production process steps and raw material costs with projections to high volumes. Some of the process improvements assumed in this "Best Case Scenario" including high speed high impact forming and solvent-less resins, have not yet been implemented, but have a high probability of potential success.

The energy crisis and pollution have posed significant risks to the environment, transportation, and economy over the last century. Thus, green energy becomes one of the critical global technologies and the use of nanomaterials in these technologies is an important and active research area. This book series presents the progress and opportunities in green energy sustainability. Developments in nanoscaled electrocatalysts, solid oxide and proton exchange membrane fuel cells, lithium ion batteries, and photovoltaic techniques comprise the area of energy storage and conversion. Developments in carbon dioxide (CO2) capture and hydrogen (H2) storage using tunable structured materials are discussed. Design and characterization of new nanoscaled materials with controllable particle size, structure, shape, porosity and band gap to enhance next generation energy systems are also included. The technical topics covered in this series are metal organic frameworks, nanoparticles, nanocomposites, proton exchange membrane fuel cell catalysts, solid oxide fuel cell electrode design, trapping of carbon dioxide, and hydrogen gas storage.

This ready reference is unique in collating in one scientifically precise and comprehensive handbook the widespread data on what is feasible and realistic in modern fuel cell technology. Edited by one of the leading scientists in this exciting area, the short, uniformly written chapters provide economic data for cost considerations and a full overview of demonstration data, covering such topics as fuel cells for transportation, fuel provision, codes and standards. The result is highly reliable facts and figures for engineers, researchers and decision makers working in the field of fuel cells.

Bipolar plates for proton exchange membrane (PEM) fuel cells are currently under development. These plates separate individual cells of the fuel cell stack, and thus must be sufficiently strong to support clamping forces, be electrically conducting, be fitted with flow channels for stack thermal control, be of a low permeability material to separate safely hydrogen and oxygen feed streams, be corrosion resistant, and be fitted with distribution channels to transfer the feed streams over the plate surface. To date, bipolar plate costs dominate stack costs, and therefore future materials need to meet strict cost targets. A first step in the bipolar plate development program is an assessment of design constraints. Such constraints have been estimated and evaluated and are discussed here. Conclusions point to promising advanced materials, such as conductive, corrosion resistant coatings on metal substrates, as candidates for mass production of fuel cell bipolar plates. Possible candidate materials are identified, and testing procedures developed to determine suitability of various materials.

The expected end of the “oil age” will lead to increasing focus and reliance on alternative energy conversion devices, among which fuel cells have the potential to play an important role. Not only can phosphoric acid and solid oxide fuel cells already efficiently convert today’s fossil fuels, including methane, into electricity, but other types of fuel cells, such as polymer electrolyte membrane fuel cells, have the potential to become the cornerstones of a possible future hydrogen economy. This handbook offers concise yet comprehensive coverage of the current state of fuel cell research and identifies key areas for future investigation. Internationally renowned specialists provide authoritative introductions to a wide variety of fuel cell types and hydrogen production technologies, and discuss materials and components for these systems. Sustainability and marketing considerations are also covered, including comparisons of fuel cells with alternative technologies.

The consumption of electricity has drastically increased over the last decade and the need for cheap energy efficient sources has augmented. Fuel cells have been proposed as possible power sources to address issues that involve energy production and the environment. A proton exchange membrane fuel cell (PEMFC) is a likely alternative as a zero-emission source due to its high efficiency, low temperature operation and high power density. The Bipolar plate is a vital element of PEM fuel cell, which supplies fuel and oxidant to reactive sites, removes reaction products, collects produced current and increases the effective contact area for higher heat and mass transport. It also represents more than 60% of the weight and 30% of the total cost in a fuel cell stack. Improving the layout of the flow-field and use of lightweight materials can significantly reduce the weight of the fuel cell stack. Different material combinations, flow-field layouts and fabrication techniques will be studied to achieve the previously mentioned functions efficiently, with the aim of obtaining higher performance. Bipolar plates with different flow field layouts have been designed and their effect on the PEM fuel cell will be measured using computational multiphysics models.

Discusses how nanostructured materials can be applied to energy devices, with an emphasis on the process of generation to storage and consumption.

This ready reference is unique in collating in one scientifically precise and comprehensive handbook the widespread data on what is feasible and realistic in modern fuel cell technology. Edited by one of the leading scientists in this exciting area, the short, uniformly written chapters provide economic data for cost considerations and a full overview of demonstration data, covering such topics as fuel cells for transportation, fuel provision, codes and standards. The result is highly reliable facts and figures for engineers, researchers and decision makers working in the field of fuel cells.

Considerable efforts are being given to develop commercially viable technologies in order to alleviate the dependence on hydrocarbons as well as to reduce carbon dioxide emission by the use of fossil fuel. The proton exchange membrane fuel cell (PEMFC) has emerged as one of the most promising clean energy technology for residential and automotive applications. The high power density, low operating temperature, convenient fuel supply, longer lifetime, and modularity are the attractive features of PEMFC. This book covers the detailed methodology for development and characterization of composite bipolar plate for PEMFC. It also includes the methodology for synthesis and characterization of graphene. The synthesized monolayer graphene was used as one of the reinforcements for the composite bipolar plate. The state of the art for development and performance evaluation of PEMFC is discussed in detail. The information presented in this book will be helpful to the researchers, academicians, and manufacturers for the development of the composite bipolar plate for PEMFC.

Materials and Technologies for Energy Efficiency is a compilation of research papers whose main aim is to provide an opportunity to gather knowledge about the latest developments and advances in materials and processes involving energy. This volume consists of a series of works which were presented at The Energy & Materials Research Conference (EMR2015), held in Madrid, Spain in February 2015. This compilation of more than 50 papers has been written by researchers from all over the world. Papers focus on topics including biomass and biofuels; solar energy; fuel cells; energy storage, etc. The book is recommended for researchers from a broad range of academic disciplines related to energy and materials. We hope that this set of papers would be useful to stimulate further discussion on energy and materials research.