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Fuel Cells for Laptop Computers

ArbiterOne writes "An article in PC World states that the company MTI Micro Fuel Cells plans to demonstrate a new technology this week that could pave the way for better power technology for laptop and palmtop computers. The article claims that this new technology could provide a battery life 2.5 times greater than that of a lithium-ion battery. Could this be the solution to the problem of short battery life in high-end notebooks?"

53 of 266 comments (clear)

  1. At long last. by LEgregius · · Score: 5, Insightful

    As long as the laptop designers don't suddenly think that having more power means they can put components that use 2.5 times the power.

    1. Re:At long last. by AviLazar · · Score: 4, Funny

      Don't worry, they already believe they can create components that use 2.5 times the power, even without the battary to power it :)

      --

      I mod down so you can mod up. Your welcome.
    2. Re:At long last. by Scoria · · Score: 5, Insightful

      A good amount of incredulity is necessary here. Remember that Lithium Ion batteries themselves were once supposedly capable of eliminating the "memory" effect and providing almost infinite battery lives. Then, of course, they were released, and the hyperbole was proven incorrect.

      --
      Do you like German cars?
    3. Re:At long last. by jeffy124 · · Score: 5, Interesting

      As long as they don't put out 2.5x the heat

      this guy would certainly agree.

      --
      The One Rule Of Chess You'll Ever Need: Don't play someone who carries a kit in their bookbag.
    4. Re:At long last. by AviLazar · · Score: 4, Funny

      Oh don't let me get into that one. "Hey lets create a game that is a huge memory hog so nobody can run it unless they are running Quad Pentium 10 processors, 95k RPM scsi hard drives (raid required), 14 gigs of ram, and THREE video cards that won't be invented for three years."

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  2. The nice thing about "normal" batteries... by Kenja · · Score: 4, Insightful

    The nice thing about "normal" batteries is that I can go to my hotel room and recharge them. The last thing I need to be doing is wandering around vegas at three in the morning trying to find some hydrogen to power my notebook for the big presentation in the morning.

    --

    "Have you ever thought about just turning off the TV, sitting down with your kids, and hitting them?"
    1. Re:The nice thing about "normal" batteries... by rosewood · · Score: 5, Insightful

      I figured these things were easily re-chargeable. If not, wtf is the point?

      I dont think you have to pack little hydrogen pairs in there...

    2. Re:The nice thing about "normal" batteries... by L.+VeGas · · Score: 5, Funny

      Only on Slashdot

      The last thing I need to be doing is wandering around vegas at three in the morning trying to find some hydrogen to power my notebook

      During my 3am Vegas wanderings, it sure wouldn't be hydrogen that I'm looking for.

    3. Re:The nice thing about "normal" batteries... by Paulrothrock · · Score: 4, Informative

      hydrogen peroxide is extremely dangerous and unstable in its pure form. Even the stuff Armadillo Aerospace is using is only 97% pure. Every bottle of hydrogen peroxide I've found in a drug store was 3%. Could a fuel cell operate on mostly water?

      --
      I'm in the hole of the broadband donut.
    4. Re:The nice thing about "normal" batteries... by baryon351 · · Score: 3, Interesting

      What do people want powering their laptops and mp3 players - a well proven electronic device with safe failure modes...

      Try telling that to the user of this laptop. No it's not common, but laptop batteries DO sometimes fail spectacularly & dangerously.

    5. Re:The nice thing about "normal" batteries... by Stephen+Samuel · · Score: 3, Interesting
      Yeah. The thing that bothers me is the thought of being asked to pay $10 for a $0.15 plastic container filled with $0.05 worth of methanol.

      For long-term mobile computing, I'd like to be able to just carry around a 1C packet of methanol to refill my computer at will.

      --
      Free Software: Like love, it grows best when given away.
    6. Re:The nice thing about "normal" batteries... by Jeremy+Erwin · · Score: 5, Funny

      By themselves, they won't cost very much. But I would expect them to also be equipped with some sort of authentication system, so as to prevent unscrupulous third parties from ruining your name brand system with inferior IP.

      And, of course, the initial fuel cells supplied with the laptop will only be half full.

    7. Re:The nice thing about "normal" batteries... by bs_02_06_02 · · Score: 3, Informative

      You could run a Stirling engine on the exhaust output and start generating electricity, or power some form of locomotion.

      500 to 700 degrees is ridiculous. That's more heat output than when running a nitro-powered radio control engine...

      When the waste heat is that high, something is seriously wrong. They need to slow the reaction down, keep that temp down, otherwise, you'll never get approval to bring it anywhere.

      You'd be better off building a small portable steam engine.

      --
      -- No sig for you!
  3. Short battery life solved... by Anonymous Coward · · Score: 5, Funny

    Could this be the solution to the problem of short battery life in high-end notebooks?

    Yes, and with their safety record it could cause the problem of short user life in high-end notebooks.

  4. Solution to short battery life by SpaceCadetTrav · · Score: 5, Funny

    Stop playing games on the company laptop.

  5. Uh... by Paulrothrock · · Score: 5, Funny
    Call me a luddite, but I don't really want hot electronic components sitting next to pressurize, flamable gas.

    I like my pubic hair, thankyouverymuch.

    But seriously, will this be available in time for current computers (like my brand-new Powerbook) to be able to upgrade to a fuel cell power source?

    --
    I'm in the hole of the broadband donut.
    1. Re:Uh... by AviLazar · · Score: 4, Insightful

      But seriously, will this be available in time for current computers (like my brand-new Powerbook) to be able to upgrade to a fuel cell power source?
      If they are waiting for permission from organizatiosn such as the Avionics commission, and potentially other organizations (hazmat restrictions?) then you could be waiting for a few years. While this is a BLANKET guess on my part, we all know how quickly gov't organizations move.
      So you are still thinking PowerBooks will be called this in ten years? :)

      --

      I mod down so you can mod up. Your welcome.
  6. TCO? by Spaceman40 · · Score: 5, Insightful

    Lithium-Ion batteries only last so long before you have to replace them completely - I wonder if they can get these to be cheap enough to be economically competitive towards the other batteries.

    If they last longer, and the cost-per-hour of use turns out to be cheaper...

    --
    I [may] disapprove of what you say, but I will defend to the death your right to say it.
  7. A friendly reminder from Smokey the Bear... by GillBates0 · · Score: 5, Funny
    When using your MTI Micro Fuel Cell based laptop at the campgrounds, always practice safety. Surround your laptop with rocks to keep the fire from spreading. Be sure when you're done with your laptop to put it out with a bucket of water and make sure it has stopped smoking before you leave the area.

    Remember what Smokey the Bear says. Only you can prevent your MTI Micro Fuel Cell based laptop from starting a forest fire.

    --
    An Indian-American Hindu committed to non-violent thought/speech/action alarmed by the global explosion of radical Islam
    1. Re:A friendly reminder from Smokey the Bear... by srussell · · Score: 4, Funny
      Be sure when you're done with your laptop to put it out with a bucket of water
      Ah, you must not have read the announcement. These things produce their own water. The next obvious step is to construct a tiny internal fire suppression system.

      Actually, the sneaker benefit of this technology is that your laptop will steam-press your pants for your ... or, at least, the thighs of your pant legs.

  8. Hello, we're running out of money. by xtal · · Score: 4, Insightful

    Pardon me while I yawn. These things have been just around the corner for a LONG TIME. It seems they get "demonstrated" when there's a pressing need for more money, and then they go away for an undefined period of time.

    Call me when I can buy one for my powerbook.

    --
    ..don't panic
  9. It's bound to happen by Stephen+Samuel · · Score: 5, Funny

    I can just see someone cycling up to a petro-can Station pulling out a steaming laptop and yelling 'Filler up fast! I'm being slashdotted!'

    --
    Free Software: Like love, it grows best when given away.
  10. Uh... by Digitus1337 · · Score: 3, Funny

    Do I want an experimental fuel cell on my lap?

  11. Longetivity! by Anonymous Coward · · Score: 3, Funny

    Now my dual 3.2Ghz EE Pentium 4 laptop time will triple to 8.3 minutes!

    1. Re:Longetivity! by theendlessnow · · Score: 3, Funny
      Now my dual 3.2Ghz EE Pentium 4 laptop time will triple to 8.3 minutes!

      You can hold it in your lap for 8.3 minutes??!! Who makes your underwear?

  12. Yes, but what about cost? by TheAtomicElec · · Score: 5, Interesting

    The article didn't seem to mention the cost of these new fuel cell batteries along with their refueling cartridges. I don't see anyone switching to new fuel cell batteries anytime soon unless the cost of the fuel cell and lots of refueling cartridges is approximately the same as a regular li-ion battery. Of course, the nice thing about this technology is that you would never actually need to plug anything in because the battery can't be recharged, just change the cartridge. Also raises the question of whether the fuel cartridges will be hot-swappable. Still, fuel cell batteries sound kewl. :)

  13. Re:RTFA it uses methanol for its hydrogen source.. by Rei · · Score: 5, Funny

    I don't know how easily you could find methanol, but *ethanol* is darn easy to come by. :) The new teenage slogan would become, "No, mom, I swear, it's for my computer!"

    --
    I just invaded Grammar Czechoslovakia and duped Grammar Neville Chamberlain; now it's on to Grammar Poland.
  14. Gas station for laptops? by lantius · · Score: 5, Interesting
    I like the idea of fuel cells for laptops and portable devices, but the obvious problem with them is obtaining fuel. We rather take it for granted that when the laptop battery runs low we can plug it in (or drop it into the charger) and within a few hours it is ready for portable use again. With a fuel-cell based solution you have to acquire new a new cartridge. It seems like the availability of fuel will directly tie to the uptake of these devices.

    Consider the typical office corridor worker, travelling to-and-fro with their tablet PC - do they really want to have to buy or refill a cartridge every day? Would it be practical to have multiple full cartridges on hand and refill them in bulk?

    I can see enjoying the option of one of these long life power units if I'm on a flight or in some environment where I need that much portable power without the opportunity to recharge, but it seems doubtful that fuel cells are going to make a major impact on portable electronics until the infrastructure solution is solved. Even still, the infrastructure exists for non-rechargable batteries, yet many people prefer devices that have modern rechargables - it just makes more sense for most situations.

    I believe fuel cells are an excellent technology, and a worthy replacement to traditional non-rechargeable batteries, but I find it unlikeley that they will supplant the current methods of use-and-recharge laptop, pda, and cellular batteries - it's just too convenient.

  15. Re:RTFA it uses methanol for its hydrogen source.. by Kenja · · Score: 4, Funny
    To paraphrase Homer.

    One for the computer, one for me, one for the computer, one for me.....

    --

    "Have you ever thought about just turning off the TV, sitting down with your kids, and hitting them?"
  16. Methanol toxicity by DFJA · · Score: 3, Insightful

    Anyone thought about the fact that Methanol is highly toxic? I can see the headline:

    "Small child dies in tragedy involving laptop".

    I've not seen any discussion of this aspect of direct methanol fuel cells on the web, but it's an important one.

    --
    43 - For those who require slightly more than the answer to life, the universe and everything.
    1. Re:Methanol toxicity by Anonymous Coward · · Score: 5, Funny

      Yeah, we should stick with safe, nutritious lithium ion batteries.

    2. Re:Methanol toxicity by Dun+Malg · · Score: 5, Interesting
      Anyone thought about the fact that Methanol is highly toxic? I can see the headline:

      "Small child dies in tragedy involving laptop".

      I've not seen any discussion of this aspect of direct methanol fuel cells on the web, but it's an important one.

      (shrug) Methanol is no more toxic than many houshold cleaners, and when sealed in a fuel cell it's probably a bit harder to get at. When's the last time someone let a child chew on their laptop battery? Even if we end up with bottles of methanol lying around, it'll certainly be no worse than having bottles of ammonia and bleach.

      --
      If a job's not worth doing, it's not worth doing right.
  17. Re:no no no by Kainaw · · Score: 4, Interesting

    If you want to be very technical about it, we nearly have that. Most of the world is flooded with high-power radio signals. By "radio", I mean AM, FM, television, cell phone, GPS, and everything else.

    Tesla proved, repeatedly, that those signals could be caught in an antenna and turned into basic AC power. However, transmitting AC power through the air would mean that the power companies could not control how much electricity you used. So, there was a lot of propoganda, using Thomas Edison as a mouthpiece, to convince the world at large that transmitting radio waves would destroy the world - even calling transmitted AC waves "the devil's science".

    Now, we've built thousands of transmission towers. Why not tap into some of that power? Sure, you can't run a laptop on the power off one 900MHz antenna, but what if you had, say 500 of them in a little bundle? Even then, if you couldn't run the laptop off it, you could use the little power you did get to trickle charge the battery - making it last a lot longer.

    Before you get freaky ideas of humping around 500 antennas on your back, take note that an effective 900MHz antenna can be as little as half and inch long. If you arrange them like spokes on a wheel, you would have a 1-inch wide disk. Now, the trick is to fit the electronics to convert the AC signal into the same small package.

    I admit, this isn't the ultimate fuel source you requested, but it is a plentiful and untapped one.

    --
    The previous comment is purposely vague and generalized, but all of the facts are completely true.
  18. Mmmm.... methanol by Anonymous Coward · · Score: 4, Funny

    Wonder how long before people start cracking the top off the fuel chargers and start mixed it with coke... sure it may cause blindness, but there are a whole lot or reasons your laptop will make you go blind. (ba-dum-ching!)

    I can just see it now... tough board meeting, heading back on the train... cracking open your fuel cells for sweet sweet relief.

    Come on... people do it with whipped cream changers! Next best thing for the liquor-added geek?

    Now to find a way to power my laptop on vodka (like Bender!)

  19. Re:Great ! by loyalsonofrutgers · · Score: 5, Interesting

    You do realize, don't you, why Bush and Co are focusing on hydrogen as the supposed future? It's so far off in terms of actually replacing much of anything that focusing on it to the detriment of other, more immediately applicable, technologies (hybridization) ensures oil's continued dominance for the foreseeable future.

    This all sort of reminds me of the company that was putting out a huge new version of their product, that was taking an incredibly long time. And all their sales people were saying... don't buy yet.. wait... basically hyping the new product. And then when the new product came out they immediately started hyping the next product. No one bought the first product as a result, the company went out of business, and the second version never appeared.

    There is a progression of technologies here, and praying for a leapfrog to the next decade's technology and ignoring more immediate technologies only benefits the oil companies, and further delays actual energy independence.

  20. also covered in NewScientist by grey1 · · Score: 4, Informative

    see New Sci home page, article is:

    • GIVE IT SOME GAS Ditch those flaky low-tech batteries: the miniature internal combustion engine is gearing up to power everything from laptops to cellphones p.26

    though of course you'll need to have paid money to read it...

    It does cover some useful stuff including the fact that any alternative to a bettery that produces even relatively small quantities of unpleasant exhaust won't be any fun in a small space - like an aeroplane cabin...

    --
    "we demand rigidly defined areas of doubt and uncertainty!"
  21. Airplane restrictions by 14erCleaner · · Score: 4, Insightful
    The article says:
    Several problems need to be worked out before fuel cells are a viable commercial technology, says Allen Nogee, principal analyst with InStat/MDR in Scottsdale, Arizona. For one thing, the U.S. Federal Aviation Administration has to decide if fuel cells will be allowed on airplanes, he says.

    Given the way laptops are used by business travellers, and where they generally need long battery life, this is probably a stopper for the whole thing.

    --
    Have you read my blog lately?
  22. Should be plenty of open bars and liquor stores... by neurocutie · · Score: 5, Insightful
    The nice thing about "normal" batteries is that I can go to my hotel room and recharge them. The last thing I need to be doing is wandering around vegas at three in the morning trying to find some hydrogen to power my notebook for the big presentation in the morning.
    It should be possible to make a fuel cell that accepts ethanol as well as methanol... Plenty of places to get gin or vodka in Vegas at 3am...
  23. excess water by apachetoolbox · · Score: 5, Funny

    Over the course of the operating period, the amount of excess water released will not be noticeable to the user, he says.

    great, now laptops can pee on us :D

  24. Fuel cell hype by Animats · · Score: 5, Insightful
    When you read articles about fuel cells, note that some of these outfits don't have refueling worked out. Some are talking about "disposable" fuel cells.

    "Disposable" fuel cells have to be compared against primary batteries, not rechargeable ones. Rechargable batteries typically have about half the energy density of primary batteries. So claiming a 2.5x improvement in battery life for a nonrechargeable system is not a win.

    Ballard is further along than anybody else in larger fuel cells. Even they don't have much more than prototypes. Their attempt to market a fuel cell under the Coleman brand was a failure. The Coleman Powermate was launched with great fanfare in 2002, and never shipped. It's not clear what's wrong at Ballard. Their 1KW units should be providing backup power for cell phone sites and such, but it isn't happening.

    Ballard uses hydrogen in their fuel cells. Despite all the hype about the "hydrogen economy", Praxair, which sells hydrogen for fuel cells, has this to say:

    • Clean burning and not considered an atmospheric pollutant, hydrogen is fast becoming the energy source of the future. Questions regarding cost, safety and infrastructure, however, need answers before hydrogen-fueled engines go into wide use.

      Fuel cell grade hydrogen is specifically designed to be used as a fuel in fuel cell applications. It contains extremely low levels of impurities (e.g. ammonia (NH3), carbon monoxide (CO) and sulfur compounds) that can harm the catalyst-coated membranes inside the fuel cell.

      It is supplied in high-pressure cylinders and can only be used by industrial customers, like factories, laboratories, universities, and military and government installations. Typically, industrial customers already use compressed gases as part of their daily activities. Its use requires adequate ventilation and/or monitoring systems appropriate to the size of the location, helping ensure the safety of personnel when non-air gases are present.

  25. What about the other way??? by Lumpy · · Score: 4, Interesting

    Why dont we see lower power laptops?

    using current tech for low power consumption they could make a laptop that has say a 500-600mhz processor and a trans-reflective TFT display like that on PDA's as well as using a hard drive/ram/flash combo to give me 3-4 days run time.

    add to it by covering the lid in flexible solar panels and you would have a laptop that is useable by most people that will trickle charge from the lighting in the office or sunlight coming in the windows/ car windows/etc....

    not everyone needs a 2.8ghz Centrino with a super 3d video card + 10,000rpm laptop hard drive to do their daily tasks.

    granted this would mean that OS makers (Microsoft you hear me?) actually start making the OS smaller and faster... but there are times that I wish I could have a sub/sub notebook taking advantage of today's tech making weigh almost nothing with gobs of battery life.

    --
    Do not look at laser with remaining good eye.
  26. Practicality. by Reeses · · Score: 4, Interesting

    Ok, maybe it's me, but it seems that no one has thought about the practical implicaitons of how this works.

    1) Take the idea of carrying your LiIon battery, and compact charger, throwing it away, and basically replacing it with the equivalent number of AA batteries needed to make a business trip.

    1a) Now think about how much your back is going to hurt after dealing with that much weight in an airport.

    2) OK, now take that thought, replace those AA batteries with something that's full of liquid, flammable liquid at that, and carry enough of those to power your laptop for a week long business trip.

    3) Disposal of the spent cartridges. And the fact that this thing spits out steam (euphemistically called water vapor in the article) right near delicate electronic components. Does it have an exhaust pipe to make sure that you don't get condensation all over your expensive computer bits?

    4) How does this really help? It might be cool to do for disposable batteries. I'd love to be able to get longer life in my flashlight with a battery like this, but not in my laptop with those kind of limitations.

    --
    Reeses
  27. with the DCMA? by oneiros27 · · Score: 4, Interesting
    The article specifically said that this company was not working on user-fillable fuel cells ... so these things will probably go the way of toner and ink cartridges:
    • other companies make a compatable form-factor
    • original company starts changing the form factor on a regular basis
    • other companies make refill kits
    • original company adds software so the cartridge thinks its empty
    • someone makes a 'tool' to convince the cartridge otherwise
    • original company sues person under the DCMA
    Okay, that's not exactly the timeline with the previous ones, but I'd expect something similiar ... don't think you're going to be able to just recharge these things from a can like for butane lighters.

    You'll go to the store, and have to buy company X's model to it your machine, but the store will be all out, because company X is having a supply problem, and no one else has a comporable model. [case in point -- I got the third to the last pack of AA batteries at the CVS near my house last week....out of 12 or so hooks of Duracell, Energizer, generics, in 4/8/12 packs, they had 2 packs of generics left after I left... I have no idea why they were that low (they could've had more in back, I didn't ask).

    If it's some proprietary format, I'm just not optimistic about finding a new battery when mine goes dead.
    --
    Build it, and they will come^Hplain.
  28. Methanol by Spazmania · · Score: 3, Informative

    From: http://www.c-f-c.com/gaslink/pure/methanol.htm

    Methanol: A colorless, flammable liquid with an odor repulsive pungent. Shipped and stored in dissolved acetone. Can decompose spontaneously if pressure exceeds 15 PSIG.

    Hazards: A toxic substance. Irriatates eyes and causes dizziness, nausea and is a possible carcinogen.

    Yeah, I'm going to carry a bottle of that onto a post-9/11 jetliner.

    --
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  29. I don't think so, and here's why: by Ayanami+Rei · · Score: 4, Informative

    Take a typical FM broadcast tower. Say, DC101 in the DC-metro area. 22.5 kWatts. That power is spread out over the entire surface area of the region. Some tens of hundreds of square miles. And the inverse-square law is a bitch. Your antenna will receive the tiniest fraction of a watt. It's a good thing your radio tuner or cellphone has a filter and amplifier to do something with it.
    You definitely can't get usable juice from that.
    No, son, if you were being irridated with narrow band EM waves that were incident in such a fashion to be able to power a laptop (say, 50 watts), without a parabolic antenna, you'd be blind, or dead. This is how microwave ovens work (in the 802.11b range, no less)

    --
    THIS THING CAN TURN ON A DIME, MACROSSZERO STYLE ALSO FUCK BETA, ~NYORON
  30. Richolson's Law by gricholson75 · · Score: 3, Funny

    I hereby announce Richolson's Law:
    Whenever an article mentioning laptop computers, parts for laptop computers, or any accessory pertaining to laptop computers is posted to Slashdot, the chances someone will link to the Register article about the man who burnt his penis with his laptop approaches 1.0.

  31. Re:(Scratches head) by neurocutie · · Score: 4, Informative
    Most of the fuel cell prototypes proposed for laptop use and similar run on methanol, not hydrogen. This is probably because it is obviously much easier to deal with a few ounces of fluid fuel rather than a high pressure compressed tank of hydrogen. It would be lunacy to allow an average consumer to deal with a tank of compressed hydrogen that has the potential of venting into open air.

    So similarly, even if a hotel would foolishly allow you to crack tap water to produce hydrogen and oxygen in your hotel room in the quantities needed without causing a fire or explosion, how would you propose to carry around these gases ? You would need a good, portable compressor to fill up a tank.

    I think if you thought about it a bit, you'd realize that supplying and storing alcohols is much more simple and practical than hydrogen, for the same reasons that this whole "hydrogen economy" notion has so many problems of practicality that it will probably never happen and that biofuels (alcohols, biodiesel, etc) are much more likely.

  32. What memory effect by lcsjk · · Score: 4, Funny

    I don't remember anything about that!

  33. Glucose based fuel cells by joncrie · · Score: 3, Interesting

    The NYTimes (reg. req'd) has a report about ongoing research on glucose-based fuel cells. Maybe instead using batteries, we'll soon just plug our laptops into our arms.

  34. Use U-235 by dpbsmith · · Score: 3, Funny

    A single aspirin-sized pellet of U-235 could power your laptop for 20,000 years. No wimpy Centrinos, but a big honkin' full-strength 43.8-watt Pentium IV. The ability to burn DVD's directly, and I do mean burn. A simple 20-pound lead plate integral with the back of the case provides your lap with thermal and other protection, as well as looking cool. Waste disposal? No problem, nobody's going to throw one away when it still has 19,997 years of useful life in it.

    1. Re:Use U-235 by egomaniac · · Score: 4, Interesting

      A single aspirin-sized pellet of U-235 could power your laptop for 20,000 years.

      I realize you're joking, but lest some of the Slashbots around here take this as insightful commentary:

      1) Unlike plutonium, U-235 is not radioactive enough to be used as a heat source for a thermoelectric generator.

      2) A small pellet of U-235 cannot generate electricity via nuclear processes. You need a critical mass in order to sustain fission, which is a minimum of around 15 kg in the case of U-235.

      3) Nuclear reactors are really just steam-driven turbines which use nuclear fission as the heat source. You could generate power just as easily by lighting a big fire and using it to boil water (and in fact that's exactly what fossil fuel plants do). Obviously, this isn't something that can be scaled down to portable sizes.

      4) You don't need anything approaching 20 pounds of lead to shield you from uranium's radioactivity. You wouldn't want to swallow it, but you could hold a bare pellet of U-235 in your hand perfectly safely, and a paper-thin layer of lead would completely block its radioactivity. The massive shielding around nuclear powerplants is primarily there to protect us from the neutrons generated during fission, which are very difficult to stop.

      --
      ZFS: because love is never having to say fsck
  35. Re:Rechargeable fuel cells? by msmikkol · · Score: 3, Interesting

    Yes, reversible fuel cells have not been left without attention, but there are some problems, both electrochemical and mechanical. First, the catalyst used for the cell can't be carbon supported platinum, which is the best for hydrogen fuel cells, since electrolysis happens in a potential region(*) where carbon is oxidized. Therefore, a non-carbon supported catalyst or a non-supported catalyst is needed and the search is still on.

    Second, storing the hydrogen might be a problem. Pressurized container are bulky and require additional components, e.g. compressors, and chemical storage systems, for example metal hydride containers are heavy and expensive.

    For most uses, there is no need to store oxygen. There's enough oxygen in air, and air is readily available in most use environments.

    * Yes, you can split water at a potential, which is under the oxidation potential of carbon, but reaction kinetics at that potential are not favorable, i.e. too slow. Therefore, practical electrolysis requires a higher potential.

    --
    The aim of science is not to open the door to infinite wisdom, but to set a limit to infinite error.
    -Bertolt Brecht
  36. Forget fuel cells, use the alternative by panurge · · Score: 3, Funny
    In the real world, fuel cell powered cars are always on the horizon, but for sheer fuel efficiency the good old direct injection Diesel is still winning. Works brilliantly on boats, and recharges my laptop in the car via an inverter.

    The obvious answer is a tiny Diesel engine. It'll probably be commercialised faster, it will run nicely on rapseseed oil, which you can carry on airplanes, and the coolness factor would be enormous. The Powerbook would doubtless have some six-cylinder BMW design with engine management and a titanium-clad alternator, while Dell would have some two-pot Chinese job that emitted black smoke while starting. Of course, the plane could still run out of salad dressing on the way to a convention, and the filler better not look too much like a hypodermic.

    --
    Panurge has posted for the last time. Thanks for the positive moderations.