Well, if they're real, then they'd do very well with those newfangled nano solar power window films which could generate power by hydrolyzing water into hydrogen tanks
So, you generate the hydrogen via electrolysis, charge the fuel cell with it, and then use the fuel cell to charge your personal electronics.
It's not obvious to me that this is much of an improvement over rechargeable batteries. I recognize that 15Wh is more than a single good AA rechargeable has (~1.5 V * ~2.1Ah = ~3.2 Wh) but they don't specify how much energy is required for the electrolysis, either. (Nor do I know what happens when you try to get hydrogen from tap water, which has a bunch of things that aren't H2O in it.)
Maybe someone that knows more about the technical aspects can comment.
If they actually work as designed, there's something to be said for the fact that we wouldn't be throwing out sagans of fairly toxic batteries as often. I have no idea if it'd come out to less energy expenditure than the whole lots-of-batteries manufacturing process, but there's a good chance that you'd have less junk to discard as a result.
Hydrogen fuel cells have been around for more than half a century. Possibly more than a century. The low pressure metal-hydrogen storage has been around for decades as well, with a lot of progress in recent years. I have made hydrogen from tap water, it works fine. Distilled water is better because it won't clog the equipment after time. Of course, the electrolysis will take more energy than the resulting hydrogen will produce. The loss varies depending on the quality of the equipment.
In short, there is no reason why the thing shouldn't work.
(Oh, and for what it is worth, I have an MA in chemistry.)
I've certainly been aware of hydrogen fuel cells for some time, as well as the lossy nature of hydrogen generation via electrolysis. So I have no concerns about
I guess at the moment my questions are really practical rather than conceptual, and I don't really expect anyone here to have the answers available, but just in case: (1) How fast do these fuel cells give up their hydrogen? (I assume that they leak at least microscopically over time.) If the answer is "really really slowly", then that might be one advantage over rechargeable batteries. (2) How fast do the fuel cells degrade over time? (I've got rechargeable batteries that are still doing well after dozens, if not hundreds, of charges, which certainly helps with the 'throwing out batteries' problem, but I have had them wear out, too.) (3) Follow-on to (2): how toxic are the fuel cell components? (4) What's the energy density of these fuel cells _in combination with the charger that they fuel_? That is, I recognize that one of those fuel cells holds 5x the Ah that a good rechargeable AA does, but it requires a good-sized charger to go with it.
I've got a solar charger that can charge mobile devices (or anything else that can be USB-powered) directly; it's about the size of the fuel-cell-powered charger. *shrug*
You've gotten down to the solid questions of quality of manufacture rather than the nature of fuel cells.
1) How fast do these fuel cells give up their hydrogen? (I assume that they leak at least microscopically over time.) If the answer is "really really slowly", then that might be one advantage over rechargeable batteries.
-This depends on how good the mechanical shut off valve is and the general hydrogen handling enclosure is. We could be talking years or five minutes.
(2) How fast do the fuel cells degrade over time? (I've got rechargeable batteries that are still doing well after dozens, if not hundreds, of charges, which certainly helps with the 'throwing out batteries' problem, but I have had them wear out, too.)
-With care, a fuel cell can last years, or the catalyst can be "poisoned" by an impurity in the hydrogen or air and go bad in a heartbeat.
(3) Follow-on to (2): how toxic are the fuel cell components?
-There can be some exotic metals in fuel cells but in small quantities and not in a particularly toxic form.
(4) What's the energy density of these fuel cells _in combination with the charger that they fuel_? That is, I recognize that one of those fuel cells holds 5x the Ah that a good rechargeable AA does, but it requires a good-sized charger to go with it.
-Because in this case the hydrogen is stored in absorbing metal, the energy density is low because of the mass used by the absorbing metal. Your good rechargeable batteries are likely to have as good or better energy density. (Just not as cool.) For space missions liquid oxygen and liquid hydrogen are used so little mass is wasted storage containers. Liquid hydrogen is just not convenient for home use.
I agree that I've jumped right into the quality of manufacture questions (for the most part), but that seems appropriate; as you and others have pointed out, the technology has been around for decades.
(I liked "liquid hydrogen is just not convenient for home use". :) )
I wonder how they solved ambient gas poisoning of the electrodes? Fuel cells need clean gasses or garbage accumulates and destroys them. Dust, pollen, smoke, methane from a gassy coworker... it all wrecks the very delicate membranes. Otherwise geeky people like me would be powering their homes with them for the past 50 years.
I for one like hydrogen cells. I think they'd make great power sources. With the right mixture of gases in them to reduce chance of critical cell failure leading to an explosion they're perfectly safe!
(no subject)
Date: 2010-06-18 12:19 am (UTC)Duuuuuude.
(See icon.)
(no subject)
Date: 2010-06-18 02:14 pm (UTC)(no subject)
Date: 2010-06-18 01:30 am (UTC)(no subject)
Date: 2010-06-18 01:38 am (UTC)(no subject)
Date: 2010-06-18 02:20 am (UTC)(no subject)
Date: 2010-06-18 03:54 am (UTC)(no subject)
Date: 2010-06-18 05:41 am (UTC)It's not obvious to me that this is much of an improvement over rechargeable batteries. I recognize that 15Wh is more than a single good AA rechargeable has (~1.5 V * ~2.1Ah = ~3.2 Wh) but they don't specify how much energy is required for the electrolysis, either. (Nor do I know what happens when you try to get hydrogen from tap water, which has a bunch of things that aren't H2O in it.)
Maybe someone that knows more about the technical aspects can comment.
(no subject)
Date: 2010-06-18 06:37 am (UTC)(no subject)
Date: 2010-06-18 04:59 pm (UTC)(no subject)
Date: 2010-06-18 10:24 am (UTC)In short, there is no reason why the thing shouldn't work.
(Oh, and for what it is worth, I have an MA in chemistry.)
(no subject)
Date: 2010-06-18 04:59 pm (UTC)I've certainly been aware of hydrogen fuel cells for some time, as well as the lossy nature of hydrogen generation via electrolysis. So I have no concerns about
I guess at the moment my questions are really practical rather than conceptual, and I don't really expect anyone here to have the answers available, but just in case:
(1) How fast do these fuel cells give up their hydrogen? (I assume that they leak at least microscopically over time.) If the answer is "really really slowly", then that might be one advantage over rechargeable batteries.
(2) How fast do the fuel cells degrade over time? (I've got rechargeable batteries that are still doing well after dozens, if not hundreds, of charges, which certainly helps with the 'throwing out batteries' problem, but I have had them wear out, too.)
(3) Follow-on to (2): how toxic are the fuel cell components?
(4) What's the energy density of these fuel cells _in combination with the charger that they fuel_? That is, I recognize that one of those fuel cells holds 5x the Ah that a good rechargeable AA does, but it requires a good-sized charger to go with it.
I've got a solar charger that can charge mobile devices (or anything else that can be USB-powered) directly; it's about the size of the fuel-cell-powered charger. *shrug*
(no subject)
Date: 2010-06-18 11:18 pm (UTC)1) How fast do these fuel cells give up their hydrogen? (I assume that they leak at least microscopically over time.) If the answer is "really really slowly", then that might be one advantage over rechargeable batteries.
-This depends on how good the mechanical shut off valve is and the general hydrogen handling enclosure is. We could be talking years or five minutes.
(2) How fast do the fuel cells degrade over time? (I've got rechargeable batteries that are still doing well after dozens, if not hundreds, of charges, which certainly helps with the 'throwing out batteries' problem, but I have had them wear out, too.)
-With care, a fuel cell can last years, or the catalyst can be "poisoned" by an impurity in the hydrogen or air and go bad in a heartbeat.
(3) Follow-on to (2): how toxic are the fuel cell components?
-There can be some exotic metals in fuel cells but in small quantities and not in a particularly toxic form.
(4) What's the energy density of these fuel cells _in combination with the charger that they fuel_? That is, I recognize that one of those fuel cells holds 5x the Ah that a good rechargeable AA does, but it requires a good-sized charger to go with it.
-Because in this case the hydrogen is stored in absorbing metal, the energy density is low because of the mass used by the absorbing metal. Your good rechargeable batteries are likely to have as good or better energy density. (Just not as cool.) For space missions liquid oxygen and liquid hydrogen are used so little mass is wasted storage containers. Liquid hydrogen is just not convenient for home use.
(no subject)
Date: 2010-06-18 11:38 pm (UTC)I agree that I've jumped right into the quality of manufacture questions (for the most part), but that seems appropriate; as you and others have pointed out, the technology has been around for decades.
(I liked "liquid hydrogen is just not convenient for home use". :) )
(no subject)
Date: 2010-06-18 03:28 pm (UTC)(no subject)
Date: 2010-06-18 05:38 pm (UTC)