I remember my physics teacher once telling me that it’s possible to make a battery last indefinately at absolute zero temperatures. He said this work because the the energy (or whatever) inside the battery isn’t reduced by the friction and therefore lasts forever. Is this true? If so, how long will it be before this is implemented and out on the market?
Well, first it’s physically impossible to reach absolute zero, but using expensive equipment you can get pretty close.
I assume when you say that the battery “lasts” indefinitely that you mean that it is not actually being used at the time - in other words, it’s being kept in (very) cold storage. That, I could buy. Theoretically, all motion within the battery would stop, and no chemical reactions could take place. (I could be wrong on this point - smarter Dopers please feel free to disagree!)
Presumably if you tried to get energy out of the battery, it wouldn’t be absolute zero anymore…
I’m just guessing here, but I’m pretty sure what your teacher was talking about wasn’t a battery. He was probably talking about superconductivity, and the fact that an electric current could run around a superconducting ring forever due to the complete lack of electrical resistance.
This differs from what you said in two ways: Superconductivity does require low temperatures (with present technology, anyway), but it doesn’t need absolute zero. Also, the current cannot be used (to power your Walkman, for instance). Once you break the ring to draw off power, the whole ‘forever’ aspect goes out the window.
In conclusion, I should point out that you can’t cool something down to absolute zero. You can get close, but you can’t get there. So, if your teacher was talking about some battery-concept I’m not aware of, it still isn’t something that will ever make it to market.
Since batteries produce electricity through chemical reactions, and chemical reactions should not happen at all at absolute zero, a battery will retain its potential to produce electricity for as long as it is kept at absolute zero (if that was possible, which it isn’t).