Hydrogen and Fuel Cell Technologies Office

Automotive proton-exchange membrane fuel cells (PEMFCs) have finally reached a state of technological readiness where several major automotive companies are commercially leasing and selling fuel cell electric vehicles, including Toyota, Honda, and Hyundai. These now claim vehicle speed and acceleration, refueling time, driving range, and durability that rival conventional internal combustion engines and in most cases outperform battery electric vehicles. The residual challenges and areas of improvement which remain for PEMFCs are performance at high current density, durability, and cost. These are expected to be resolved over the coming decade while hydrogen infrastructure needs to become widely available. Here, we briefly discuss the status of automotive PEMFCs, misconceptions about the barriers that platinum usage creates, and the remaining hurdles for the technology to become broadly accepted and implemented.

Much of hydrogen's value to the energy-system lies in its ability to be cleanly and efficiently converted between chemical and electrical energy, while also possessing the high energy density and long-term storage potential of chemical bonds. For these reasons, hydrogen's importance is expected to grow substantially in the coming decades, providing cross-sector and cross-temporal impact through clean, efficient processes. Many of these processes are electrochemical in nature, such as electrolysis of water and electricity production using fuel cells. Hydrogen also offers significant flexibility in how it can integrate into the energy system as a function of scale (from W to GWs), source (fossil fuels, nuclear, biomass, solar, wind, thermal), and end use (grid, buildings, industry, transportation). This flexibility, along with the ability to be used as a dispatchable load or power generation source, allows hydrogen and hydrogen-based processes to couple with the overall energy system in an integrated or hybridized fashion, offering dramatic system optimization potential. However, achieving the scale necessary to have impact – the vision 'Hydrogen at Scale' (H2@Scale)" still has research challenges, many of which center around electrochemistry.

We assess the strengths and weaknesses of strategies for creating nanoporous hydrogen storage sorbents.

The authors in this collection offer comprehensive and definitive summaries of important topics in photoelectrochemical hydrogen production.

A highly active NiMo electrocatalyst for HOR in alkaline media with power density at 0.5 V higher than 100 mW cm⁻² (peak value of 120 mW cm⁻²), which is similar to palladium was synthesized and comprehensively studied.

Alkaline exchange membrane fuel cells (AEMFCs) have advanced rapidly in recent years and now show improved potential to become a low-temperature fuel cell alternative to proton exchange membrane fuel cells. To date, performance and durability are still too low to meet the promised reductions in materials cost, especially demonstration of platinum group metal- and precious metal-free AEMFCs. U.S. Department of Energy technical milestones for the next ten years are laid out herein. These milestones focus on the major barriers to AEMFC viability, hastening economic competitiveness and application relevance. Standard test conditions will facilitate benchmarking of AEMFC catalysts and membranes.

Abstract Proton conducting ceramics show promise in fuel cells, electrolyzers, permeation membranes, sensor applications, and membrane reactors. Among several types of materials that exhibit proton conduction, perovskite oxides show high proton conductivity at intermediate temperatures, presenting potential benefits for long-term use and lower costs for energy applications. Doped barium zirconate, BaZrO 3 , is a material that has shown high proton conductivity with encouraging chemical stability. Therefore, it is considered a promising material especially for proton-conducting solid oxide electrochemical cells. Although the proton conduction of doped BaZrO 3 has been extensively characterized, the specific phenomena behind its proton conduction are not fully understood. Only recently have specialized techniques and computational tools begun to elucidate the phenomena that determine the conduction properties of the material. In this mini review, an evaluation of the factors affecting the proton conductivity of doped BaZrO 3 perovskites and the phenomena governing variations in proton concentration and mobility are presented. Special attention is given to proton interactions with dopants and their resulting effect on hydration and transport properties. Technical strategies are provided to give some guidance on the development of protonic ceramics in energy conversion applications.

The Department of Energy (DOE) Hydrogen Program supports research and development that has substantially improved the state-of-the-art in fuel cell technology, especially with regard to the major technical hurdles to fuel cell commercialization - durability, performance, and cost of fuel cell components and systems. In particular, membrane and catalyst structure and composition have been found to be critical in obtaining improved performance and durability. For example, advancements in alloy catalysts, novel catalyst supports, and mechanically-stabilized membranes have led to single-cell membrane electrode assemblies (MEAs) with platinum metal group loadings approaching the DOE 2015 MEA target that have a lifetime of 7,300 hours under voltage cycling, showing the potential to meet the DOE 2010 automotive fuel cell stack target of 5,000 hours (equivalent to 150,000 miles). In addition, improvements in the performance of alloy catalysts and membranes have helped improve overall performance and reduce the modeled cost of an 80-kW direct hydrogen fuel cell system for transportation projected to a volume of 500,000 units per year to $73/kW. While component research enabled such advances, innovation in characterization and analysis techniques has improved researchers' understanding of the processes that affect fuel cell performance and durability. An improved understanding of these processes will be key to making further progress in eliminating cost, durability, and performance challenges that remain for fuel cell technology.

In order to determine a material's hydrogen storage potential, capacity measurements must be robust, reproducible, and accurate. Commonly, research reports focus on the gravimetric capacity, and often times the volumetric capacity is not reported. Determining volumetric capacities is not as straight-forward, especially for amorphous materials. This is the first study to compare measurement reproducibility across laboratories for excess and total volumetric hydrogen sorption capacities based on the packing volume. The use of consistent measurement protocols, common analysis, and figure of merits for reporting data in this study, enable the comparison of the results for two different materials. Importantly, the results show good agreement for excess gravimetric capacities amongst the laboratories. Irreproducibility for excess and total volumetric capacities is attributed to real differences in the measured packing volume of the material.

Among heavy industrial sectors worldwide, the steel industry ranks first in carbon dioxide (CO 2 ) emissions. Technologies that produce direct reduced iron (DRI) enable the industry to reduce emissions or even approach net‐zero CO 2 emissions for steel production. Herein, comprehensive cradle‐to‐gate (CTG) life cycle analysis (LCA) and techno‐economic analysis (TEA) are used to evaluate the CO 2 emissions of three DRI technologies. Compared to the baseline of blast furnace and basic oxygen furnace (BF–BOF) technology for steel making, using natural gas (NG) to produce DRI has the potential to reduce CTG CO 2 emissions by 33%. When 83% or 100% renewable H 2 is used for DRI production, DRI technologies can potentially reduce CO 2 emissions by 57% and 67%, respectively, compared to baseline BF–BOF technology. However, the renewable H 2 application for DRI increases the levelized cost of steel (LCOS). When renewable natural gas (RNG) and clean electricity are used for steel production, the CTG CO 2 emissions of all the DRI technologies can potentially be reduced by more than 90% compared to the baseline BF–BOF technology, although the LCOS depends largely on the cost of RNG and clean electricity.

Hydrogen fuel cells are an important part of a portfolio of strategies for reducing petroleum use and emissions from medium and heavy duty (MD and HD) vehicles; however, their deployment is very limited compared to other powertrains. This paper addresses gaseous hydrogen storage tank design and location on representative MD and HD vehicles. Storage design is based on vehicle size and occupation. The available storage space on representative vehicles is assessed and is used to estimate the weight and capacity of composite material-based compressed gaseous storage at 350 and 700 bar. Results demonstrate the technical feasibility of using hydrogen storage for fuel cell electric trucks (FCETs) across a wide range of the MD and HD vehicle market. This analysis is part of a longer-term project to understand which market segments provide the maximum economic impact and greenhouse gas reduction opportunities for FCETs.

As with the distribution of any commodity, distribution of hydrogen depends on how the hydrogen is packaged, how far it must travel, and how much must be delivered. Few would argue that transporting a high-pressure gas is markedly different from transporting a cryogenic liquid—or even a liquid at standard temperature and pressure. Packaging affects not only density (weight/volume) but also the operation of potential delivery modes and onboard storage, a problem that has been called the grand challenge of the hydrogen economy. These three factors—packaging (which in turn affects shipment size and modal attributes), delivery distance, and demand—affect both the structure of potential delivery systems and their contribution to unit costs. This paper describes the hydrogen delivery scenario analysis model, a generalized model of hydrogen delivery that can be used to analyze the economic feasibility of various options for hydrogen distribution to markets of different sizes and types. Inputs may be user defined, or default values developed for the U.S. Department of Energy's Hydrogen Analysis project may be used. This paper describes the model's structure and capabilities, presents initial results, and discusses ongoing enhancements.

Medium and heavy duty (MD and HD respectively) vehicles are responsible for 26 percent of the total U.S. transportation petroleum consumption [1]. Hydrogen fuel cells have demonstrated value as part of a portfolio of strategies for reducing petroleum use and emissions from MD and HD vehicles [2] [3], but their performance and range capabilities, and associated component sizing remain less clear when compared to other powertrains. This paper examines the suitability of converting a representative sample of MD and HD diesel trucks into Fuel Cell Electric Trucks (FCETs), while ensuring the same truck performance, in terms of range, payload, acceleration, speed, gradeability and fuel economy.

Impedance spectra of a PEM fuel cell with three Fe-N-C cathodes have been measured under the H2/N2 testing regime. The spectra have been fitted using a recently developed physics-based impedance model, which takes into account finite proton (σp) and electron (σe) conductivity of the oxygen-free cathode catalyst layer. Fitting allowed to extract numerical data for σp, σe, the double layer capacitance, and the inductance of cables used for measuring impedance spectra. The values of σp and σe are close to what previously found for standard Pt/C electrodes, which is found for the first time using PGM-free catalysts. The method enables simultaneous measurement of reference proton and electron conductivity of PEMFC cathode.

Hydrogen has many positive attributes that make it a viable choice to augment the current portfolio of combustion-based fuels, especially when considering reducing pollution and greenhouse gas (GHG) emissions. However, conventional methods of storing H2 via high-pressure or liquid H2 do not provide long-term economic solutions for many applications, especially emerging applications such as man-portable or stationary power. Hydrogen storage in materials has the potential to meet the performance and cost demands, however, further developments are needed to address the thermodynamics and kinetics of H2 uptake and release. Therefore, the US Department of Energy (DOE) initiated three Centers of Excellence focused on developing H2 storage materials that could meet the stringent performance requirements for on-board vehicular applications. In this review, we have summarized the developments that occurred as a result of the efforts of the Metal Hydride and Chemical Hydrogen Storage Centers of Excellence on materials that bind hydrogen through ionic and covalent linkages and thus could provide moderate temperature, dense phase H2 storage options for a wide range of emerging Proton Exchange Membrane Fuel Cell (PEM FC) applications.

In 2019, U.S. petroleum refineries emitted 196 million metric tons (MT) of CO2, while the well-to-gate and the full life cycle CO2 emissions were significantly higher, reaching 419 and 2843 million MT of CO2, respectively. This analysis examines decarbonization opportunities for U.S. refineries and the cost to achieve both refinery-level and complete life-cycle CO2 emission reductions. We used 2019 life-cycle CO2 emissions from U.S. refineries as a baseline and identified three categories of decarbonization opportunity: (1) switching refinery energy inputs from fossil to renewable sources (e.g., switch hydrogen source); (2) carbon capture and storage of CO2 from various refining units; and (3) changing the feedstock from petroleum crude to biocrude using various blending levels. While all three options can reduce CO2 emissions from refineries, only the third can reduce emissions throughout the life cycle of refinery products, including the combustion of fuels (e.g., gasoline and diesel) during end use applications. A decarbonization approach that combines strategies 1, 2, and 3 can achieve negative life-cycle CO2 emissions, with an average CO2 avoidance cost of $113–$477/MT CO2, or $54–$227/bbl of processed crude; these costs are driven primarily by the high cost of biocrude feedstock.

Global demand for data and data access has spurred the rapid growth of the data center industry. To meet demands, data centers must provide uninterrupted service even during the loss of primary power. Service providers seeking ways to eliminate their carbon footprint are increasingly looking to clean and sustainable energy solutions, such as hydrogen technologies, as alternatives to traditional backup generators. In this viewpoint, a survey of the current state of data centers and hydrogen-based technologies is provided along with a discussion of the hydrogen storage and infrastructure requirements needed for large-scale backup power applications at data centers.

Abstract Hydrogen absorption and desorption isotherms have been measured for several metal hydride alloys identified as possible candidates in the high-pressure (i.e. >80 MPa) stage of a two-stage hydrogen compressor. The isotherms were obtained using two independent Sieverts volumetric test systems built specifically for measuring hydrogen absorption and desorption parameters from 0.10 to 100 MPa. The results obtained enabled us to identify the alloy Ti 0.8 Zr 0.2 Fe 1.6 V 0.4 as the most viable of the candidates investigated for use in the high-pressure stage of a prototype two-stage 80+ MPa compressor, as it produced the highest desorption pressures at moderate temperatures. Issues and challenges in determining reliable isotherms at pressures >50 MPa are also described.

This report provides an update on the status of the hydrogen and fuel cell industry, including deployments and demonstrations of various applications, as well as a snapshot of the business and governmental landscape for the year 2019. Supported by the U.S. Department of Energy’s Hydrogen and Fuel Cell Technologies Office, it follows the format of prior market reports and provides a factual, unbiased view of the technology and market status.

The authors' goal is to greatly increase access to the Arctic Ocean by creating and demonstrating a safe and economical platform capable of basin-scale surveys. Specifically, they are developing an autonomous underwater vehicle (AUV) for Arctic research with unprecedented endurance, and the capability to relay data through the Ice to satellites. They provide a means of monitoring changes taking place in the Arctic Ocean and investigate its impact on global climate changes. The vehicle will also be capable of seafloor surveys throughout the Arctic basin. Such a capability is of national and global interest and importance.