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MIT Produces Electricity Using Thermopower Waves
MikeChino writes "MIT scientists have discovered a never-before-known phenomenon wherein carbon nanotubes can be used to harness energy from 'thermopower waves.' To do this they coated the nanotubes with a reactive fuel and then lit one end, causing a fast-moving thermal wave to speed down the length of the tube. The heat from the fuel rises to a temperature of 3,000 kelvins, and can speed along the tube 10,000 times faster than the normal spread of this chemical reaction. The heat also pushes electrons down the tube, which creates a substantial electrical current. The system can output energy (in proportion to its weight) about 100x greater than an equivalent weight lithium-ion battery, and according to MIT the discovery 'opens up a new area of energy research, which is rare.'"
Instead of having a Lion battery that explodes we now have a deliberately exploding battery.
A bullet may have your name on it but splash damage is addressed "To whom it may concern."
They never said it was practical yet. It is a new area of research. Only time will tell if they discovered something useful or if they were rolling something else in a "tube" shape and smoking... ehm I mean lighting it.
"The stupid neither forgive nor forget; the naive forgive and forget; the wise forgive but do not forget." -Thomas Szasz
Yes and it's going to start a whole new era of Boom Energy
Refueling could be as simple as pouring more fuel on the nanotubes. But it may also be irrelevant -- not all power systems need to be reusable. For example, an emergency beacon is not likely to be used frequently, so refueling is not nearly as important as shelf life. And even in applications where refueling is desirable, the increased power density may be worth it -- if you phone battery lasted 200 days instead of 2 days you might not care that the battery can only be refueled with special equipment.
That being said, 100x might well be optimistic. Or it might be wildly conservative. Since this is a brand new field it seems unlikely that an estimate will be terribly accurate.
For some perspective that is about the heat that a filament in a lightbulb is at.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
Well, on the scale of the tube, we're not talking about that much thermal energy. Sure, it's a high temperature, but something the size of a nanotube (around 1/50,000 the width of a human hair) won't have a significant amount of energy. It really depends on the density of these tubes that's needed to achieve a usable amount of energy. And don't forget, we're talking about localized heating here... It's not that the tubes and structure need to get to 3000*k, that's just the temperature of the flame front.. A good example of the difference is the internal combustion engine... The flame front can reach around 2300*K, but the parts its made of would begin to weaken long before that: Iron's melting point is 1800*K (the material commonly used as a cylinder lying), Aluminum's melting point is only 900*K (the material commonly used for the engine block). But engines rarely melt... Steel (commonly used for the valves in the combustion chamber) loses about 50% of its strength at only 800*K... Yet these parts --aside from mechanical failure-- survive...
If a man isn't willing to take some risk for his opinions, either his opinions are no good or he's no good
This sounds like a niche energy product. Basically nano-combustion that very quickly creates a very strong electrical charge.
Doesn't sound too great as a battery. But as "ammo" for hand held laser weapons? Could be perfect for that.
The "fuel" used, cyclotrimethylene trinitramine, may be better known as the explosive RDX.
"FDA staff reviewers expressed concern about the number of patients who were left out of the study because they died."
3000-273=2727C They were rounding. Also thermodynamic efficiency is easier to calculate in kelvins and is standard practice in thermodynamics; see carnot cycle for details.
Sigs are too short to say anything truly profound so read the above post instead.
I agree--but I am *really* looking forward to my flaming electric car. Better start trying to snag the GHST RDR plate now....
With really REALLY small paintbrushes