“we have tried to break this paradigm of tradeoffs in materials (by improving) both the stability and the conductivity of this membrane at the same time, and that is what we were able to do with this unique polymeric materials design,” said michael hickner, associate professor of materials science and engineering.

in solid-state alkaline fuel cells, anion exchange membranes conduct negative charges between the device’s cathode and anode — the negative and positive connections of the cell — to create useable electric power. most fuel cells currently use membranes that require platinum-based catalysts that are effective but expensive.

hickner’s new polymer is a unique anion exchange membrane — a new type of fuel cell and battery membrane — that allows the use of much more cost-efficient non-precious metal catalysts and does not compromise either durability or efficiency like previous anion exchange membranes.

“what we’re really doing here is providing alternatives, possible choices, new technology so that people who want to commercialize fuel cells can now choose between the old paradigm and new possibilities with anion exchange membranes,” hickner said.

creating this alternative took some intuition and good fortune. in work spearheaded by nanwen li, a postdoctoral researcher in materials science and engineering, hickner’s team created several variations of the membrane, each with slightly different chemical compositions. they then ran each variation under simulated conditions to predict which would be optimal in an actual fuel cell. the researchers report their findings in a recent issue of the journal of the american chemical society.

based on these initial tests, the group predicted that the membranes with long 16-carbon structures in their chemical makeup would provide the best efficiency and durability, as measured respectively by conductivity and long-term stability.

chao-yang wang, william e. diefenderfer chair of mechanical engineering, and his team then tested each possibility in an operating fuel cell device. yongjun leng, a research associate in mechanical and nuclear engineering, measured the fuel cell’s output and lifetime for each material variation.

despite predictions, the membranes containing shorter 6-carbon structures proved to be much more durable and efficient after 60 hours of continuous operation.

“we were somewhat surprised…that what we thought was the best material in our lab testing wasn’t necessarily the best material in the cell when it was evaluated over time,” said hickner, who added that researchers are still trying to understand why the 6-carbon variation has better long-term durability than the 16-carbon sample in the fuel cell by studying the operating conditions of the cell in detail.

because the successful membrane was so much more effective than the initial lab studies predicted, researchers are now interested in accounting for the interactions that the membranes experienced while inside the cell.

“we have the fuel cell output — so we have the fuel cell efficiency, the fuel cell life time — but we don’t have the molecular scale information in the fuel cell,” hickner said. “that’s the next step, trying to figure out how these polymers are working in the fuel cell on a detailed level.”

the advanced research projects agency-energy at the u.s. department of energy, funded this project in collaboration with proton onsite, a leading membrane electrolyzer company based in connecticut.

•  panasonic aiming for battery-powered homes by 2011
•  battery breakthrough technology could power homes for pennies per kilowatt hour

we talk about battery-powered cars. why not battery-powered homes? these super batteries could even be fuel cells. it’s time to take innovation from the car to the home. it’s time. but, utility companies and government seem to conspire on discouraging homes to be off the grid.

but, as the u.s. power grid is already challenged, why not encourage houses to have the option to go off the grid during certain times of overload, when the house can subsist off the batter or fuel cell instead?

and as appliances get smarter, use less power, this surely seems possible today or in the next few years. the fuel cell or super battery that powers the home could get charged from the grid initially and/or through a combination of solar, wind, water, geothermal, natural gas and/or more.

the time is now, as millions every year go through more and more power outages due to severe weather. and, power outages can be quite harsh and even deadly in extreme heat or cold. as we become a wireless communication society with fewer and fewer landlines, why not evolve homes to have wireless electricity?

microbial fuel cells are a potential source of green energy, producing electricity without combustion while cleaning wastewater. but, before industry builds commercial facilities, researchers must carefully assess the production capabilities and engineering designs of biofilm reactors. the northwestern university research identified a design issue that could bear significantly upon reactors’ production capacity.

the findings also highlight the ability of scientific computing to complement laboratory research. laboratory experiments cannot reveal the small-scale structure of biofilms or other precise information related to microbial fuel cell power production. nor can they explain the sharp decrease in power production that occurs as biofilms mature.

to address this gap, researchers simulated the fuel-cell activity using mathematical models. they discovered that the biofilm overgrowth can lead to power loss. the images at right show how even slight bacterial overgrowth can lead to regions in the reactor with drastically reduced power production.

the initiative for sustainability and energy at northwestern university did the computer modeling in collaboration with laboratories at arizona state university and the university of wisconsin, milwaukee. the research serves as an example of how mathematicians, scientists and engineers can combine their talents to solve challenging problems.

a battery is an energy storage device. fuel cells, however, are energy conversion devices. they allow the conversion of chemical energy to electrical energy. we are working to develop high performance fuel cells using the most efficient and cost effective materials.

this video but university of mississippi students highlights research there to develop hydrogen fuel cells for cars, which could reduce the need for oil and gasoline.

lyrics:

gasoline gets people where we gotta go, but let’s talk a little bit about the price though.
at the pump we know it’s like a living hell, but, even worse, we’ve been damaging the earth as well.
and there are other choices that we could be taking:  a hydrogen fuel cell is in the making.
it breaks down water, turning it into fuel, emitting zero pollution, which is real cool.
but what about dollar signs, talk about the fee.  to keep the earth clean tell me what it costs me.
to drive it around cost almost none, but the fuel cell cost about a million.
see the platinum inside it is the problem now.  we need to run it without it; nobody knows just how.
we don’t want coal or electricity, but, most of all, you see, we can’t afford platinum.

and so a friend of mine is trying to find a better way.  doctor ritchie’s researching, looking towards a better day.
he’s gonna have a say in lowering the cost of driving your car, saving you the cash that you would’ve lost.
see we have had a fuel cell, and, well, it’s been nice, but it’s been unaffordable because the price was too high.
so the bottom line is doctor ritchie’s up and at ’em, finding a way that we don’t gotta use platinum.

in the original proposed project, the students were going to build a hydrogen fuel cell version of the car to test as well. however, delivery problems for the fuel cell and a very tight project timeline made it impossible to build both cars before the students would need to enter their project in the epa’s p3 competition (http://www.epa.gov/p3/). because of the similarities between the battery electric system and fuel cell system and the data gathered during road testing, it was simple to design the vehicle and to include the hydrogen fuel cell version of the vehicle in the sustainability analysis. perhaps a future team will build the fuel cell version to validate the design and performance analysis.

the tested vehicle uses very little energy and could easily be charged from either a home-installed solar panel or by purchasing “green power” from the local utility.