Fuel Cell Nation

Improved Membrane Water Transport

Robert Moore and Louis Madsen's groups at Virgina Tech claim to have done something quite interesting: increase the diffusivity of water in DuPont's Nafion^TM, the 50-year old membrane that is at the core of much current hydrogen fuel cell and electrolyzer work!

How did they do this? By stretching the Nafion^TM, using a draw ratio of up to 4:1.

Apparently, their data show that the water-conducting channels within the membrane become aligned during the stretching process. (See Figure 4 below.) In Figure 4.a, random water channels exist in the as-received membrane. In Figure 4.b, there is some alignment in the draw direction (blue arrow). Finally, in the at a 4:1 draw ratio shown in Figure 4.c, there is significant water channel alignment. Similar to nematic liquid crystals, the stretching does not change the water channel alignment or connectivity; this leads to anisotropic water transport.

Li et al Figure 4

The anisotropic nature of the water transport behavior is evident in the following Figure 2:

Li et al Figure 2

In the left figure, Figure 2.a, you can see how the diffusivity of water in the draw, or X direction (D_xx) is markedly higher than the diffusivity in the transverse directions (D_yy and D_zz). This relationship holds for all draw ratios tested, between 1:1 (as-received membrane) and 4:1.

Their data in Figure 2.a have been arithmetically averaged and plotted in Figure 2.b. This figure shows that the average water diffusivity curves for all the drawn membranes collapse to match that of the isotropic, as-received membrane.

What are the practical applications of this? Well, it may be possible to align membrane water passageways in the through-plane direction through the use of electric or magnetic field alignment methods used on liquid crystals, liquid crystal polymers and block copolymers. The resultant aligned membrane would have increased through-plane water (and proton) transport, resulting in improved PEM device (e.g. fuel cell) operation.

The complete paper is available at:

Jing Li, Jong Keun Park, Robert B. Moore & Louis A. Madsen; "Linear coupling of alignment with transport in a polymer electrolyte membrane," Nature Materials | Letter, 10(7):507-11; Jun 19, 2011.

DOE Webinar Recording: Top 5 Fuel Cell States

In my recent post DOE Webinar: Top 5 Fuel Cell States, I mention that the webinar recorded June 21, 2011 will be made available on-line.

Here is the recorded webinar. (It is in WMV format, so it's better to open it in Internet Explorer than in Firefox.)

In case you miss it during the hour-long presentation, the top 5 states are:

• California
• Connecticut
• New York
• South Carolina
• Ohio

(As an aside, just like the the May 23, 2011 webinar titled "Hydrogen Production by PEM Electrolysis—Spotlight on Giner and Proton," this webinar also had audio problems. Not sure if bad audio is an ongoing problem at gotomeeting.com, but neither webinar escaped audio problems!)

DOE Webinar: Top 5 Fuel Cell States

 
Looks like the U.S. DOE is getting into the Internet age! Coming shortly on the heels of the Webinar "Hydrogen Production by PEM Electrolysis—Spotlight on Giner and Proton", here is "DOE and Partners to Host Webinar June 21: Top Five Fuel Cell States – Why Local Policies Mean Green Growth". The Webinar is Tuesday, June 21, 2011 from 12:00 to 1:00 PM EDT.

 This webinar is with the Technology Transition Corporation and the Clean Energy States Alliance, and will discuss state policies and business development details. It is designed to supply information to companies thinking of buying a fuel cell energy system, as well as states that are interested in expanding their fuel cell incentives.

Hopefully these DOE efforts will enable and expansion of domestic fuel cell activities!

US DOE Electrolyzer Webinar Presentations

DOE has finally posted the slide presentations and audio from the May 23, 2011 Webinar titled "Hydrogen Production by PEM Electrolysis—Spotlight on Giner and Proton."

 

Overview presentation slides, Eric Miller, U.S. Department of Energy (DOE).

 

Monjid Hamdan's presentation slides, Giner Electrochemical Systems, LLC.

 

Katherine Ayers' presentation slides, Proton Energy Systems.

 

And (please excuse the audio) the webinar recording: (WMV 94 MB).

Hydrogen in Massachusetts

Everybody knows about the major hydrogen/fuel cell goings on in California. And many people know of the millions of dollars that the state of Connecticut is putting into fuel cells. However, Massachusetts has some hydrogen/fuel cell organizations as well!

The Northeast Electrochemical Energy Storage Cluster is a network of commercial, academic and government members striving to accelerate the development and implementation of hydrogen production and fuel cell technologies.

The Massachusetts Hydrogen Coalition, Inc. is a non-profit that is expanding hydrogen, fuel cell and related industries in Massachusetts by increasing resource availability, expanding visibility, and creating marketing and partnering opportunities.

The Massachusetts Clean Energy Center is the first state agency in the nation dedicated solely to facilitating the development of the clean energy industry. Besides hydrogen and fuel cells, they support solar, wind, and other green energy technologies.

Now we just need surcharges on energy utility company bills (like California's and Connecticut's) that get used to promote renewable hydrogen and fuel cells!

US DOE Electrolyzer Webinar

Its not much advanced warning, but today the U.S. Department of Energy (DOE) announced it is putting on a webinar on Monday, May 23, 2011, from 12:00 – 1:30 p.m. (EDT) titled "Hydrogen Production by PEM Electrolysis—Spotlight on Giner and Proton." The webinar will include a discussion of the importance of electrolysis for renewable hydrogen production with zero carbon footprint (provided you use solar, wind, etc. to generate the electric power.) (The webinar was originally supposed to be at 1:00 p.m., but the DOE personnel had another meeting crop up.)

 Monjid Hamdan of Giner Electrochemical Systems (GES) will be one of the two industry-based presenters at the webinar. I've seen his slides; it should be a good presentation for all, as it involves an emphasis on the technology, and its not just a sales job for GES' commercial products.

One final note: DOE calls it Polymer Electrolyte Membrane (PEM) electrolysis, while old-school electrochemists prefer to call it Proton Exchange Membrane (PEM) electrolysis. Same difference — its all good!

Crystal City, Here I Come!

Time for the 2011 U.S. Department of Energy (DOE) Hydrogen and Fuel Cells Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting (AMR). May 9-13, 2011 I am traveling to the Crystal City Marriott and Crystal Gateway Marriott, in Arlington, Virginia to make a poster presentation. The Poster is for the first year of a Phase II Small Business Innovative Research (SBIR) grant I wrote titled "Unitized Design for Home Refueling Appliance for Hydrogen Generation to 5,000 psi."

The Poster presentation for the last year's Phase I work at Giner Electrochemical Systems, LLC is located here: Unitized Design for Home Refueling Appliance for Hydrogen Generation to 5,000 psi.

Here is some background on the project:

"U.S. automakers have invested significant resources in the research and development of hydrogen fuel cell vehicles. However, to enable their widespread use, an additional major investment will be required to construct an infrastructure for hydrogen production and delivery to fueling stations. In order to facilitate this transition, the DOE has recommended that high-pressure hydrogen generation for home refueling of fuel cell vehicles be implemented as an intermediary approach.

GES has developed PEM-based electrolyzer technology for producing hydrogen at moderate to high pressure directly in the electrolyzer stack ... A low-cost process for producing high-pressure hydrogen from water by electrolysis will significantly advance the development of the hydrogen economy, providing hydrogen for fuel cell vehicles at a price competitive with that of gasoline on a per-mile basis. The ability to produce hydrogen economically, the relatively low capital cost of the electrolyzer unit, and the low maintenance cost of the unit will allow widespread distribution of hydrogen home fueling appliances deemed necessary for the introduction of fuel cell vehicles."

I just submitted a U.S. Patent application on this idea, so I can't really say anything in addition to what's in the public documents. But, enjoy!

Global Observer - Oops!

Edwards Air Force Base            (Craig Butz photo)

AeroVironment (AV) had quite an April Fool's Day event!

At 2:30 am PDT on April 1, 2010, the liquid hydrogen-fueled Global Observer unmanned air vehicle (UAV) "experienced a mishap" during extended duration flight testing. Personnel at Edwards Air Force base, where the Global Observer testing was based, report that it crashed. The crash occurred approximately 18 hours into its 9th test flight. The Global Observer was conducting "envelope expansion" flight testing, flying higher and for a longer duration than it had previously. Crash details are sparse, probably because AV has been ordered by the US government not to discuss the accident until after an investigation was completed. Crashes during developmental testing are not unusual, as Northrop Grumman suffered from the loss of a prototype RQ-4 Global Hawk during flights in 1999.

In my previous post, Hydrogen for 65,000 Feet, I discuss how the Global Observer was designed to fly for five to seven days, powered by liquid hydrogen, at altitudes up to 65,000 feet. Design criteria included 2.8 kilowatts (kW) of power for a 380-lb. payload, and a liquid hydrogen-fueled internal combustion engine producing about 60 kW of electricity.

AV received a US$140 million contract in September 2007 for a Joint Capability Technology Demonstration (JCTD) of the Global Observer (GO-1). Three GO-1s were planned on being built under the JCTD, jointly overseen by six U.S. government agencies. The second air vehicle is nearing completion at the AV factory. The third unit was supposed to be a backup, but it has not been discussed since the order was announced in June 2009. AV has recently stated that most of the funding for the program has been spent.

The worst part for AV is that this high-profile crash comes after another high-profile crash 8 years ago. On June 26, 2003, the NASA-funded Helios prototype UAV broke up and fell into the Pacific Ocean about 30 minutes after take-off from Kauai, in the Hawaiian islands. Helios had been quite a successful UAV, because on August 14, 2001, Helios set a world record for a winged aircraft at an altitude of 96,863 feet (29,523.8 m). Unlike Global Observer, Helios had solar cells, an electrolyzer supplied by Giner Electrochemical Systems designed to produce hydrogen and oxygen for storage, and a fuel cell fueled by the hydrogen and oxygen to produce power overnight.

According to Wikipedia,

"The (Helios) investigation report identified a two-part root cause of the accident:

1. Lack of adequate analysis methods led to an inaccurate risk assessment of the effects of configuration changes leading to an inappropriate decision to fly an aircraft configuration highly sensitive to disturbances.

2. Configuration changes to the aircraft, driven by programmatic and technological constraints, altered the aircraft from a spanloader to a highly point-loaded mass distribution on the same structure significantly reducing design robustness and margins of safety."

Hopefully AV can quickly get beyond this latest tragedy to continue their groundbreaking work. And hopefully the conclusions of the Global Observer investigation are not as painful as those of the Helios investigation. AV better hurry, though, as Boeing plans to fly its company-funded Phantom Eye hydrogen-fueled high-altitude, long endurance (HALE) UAV demonstrator at Edwards later this year, and Aurora Flight Sciences hopes to fly their Orion twin diesel engine-powered, five-day-endurance medium-altitude UAV this year under an Air Force-sponsored JCTD.

 (Boeing photo)         (S. Schaeffer-Hopkins photo)