Ultra-fast charging aluminum batteries

[iwire]

An interesting article about a new battery technology.

Hopefully it pans out.


http://phys.org/news/2015-04-ultra-fast-aluminum-battery-safe-alternative.html

 

[winnie]

I hope that this pans out as well. Faster, cheaper energy storage is very useful.

I should note, however, that 'fast charging' and 'safe' are just about mutually exclusive.

Fast charging means low internal impedance, which equates to high short circuit current. The faster you can charge the faster you can discharge, and the faster you can discharge the more damage you can do in a fault. If you think a 9V battery shorted by keys in your pocket is a problem....

And no, I am not trying to dismiss this technology; if it pans out it will be very useful. My point is that the _ideal_ battery is one that stores energy with no losses and can release that energy rapidly with no losses. In the limiting case an 'ideal' battery is very similar to an 'ideal' bomb.

-Jon

 

[iwire]

My point is that the _ideal_ battery is one that stores energy with no losses and can release that energy rapidly with no losses. In the limiting case an 'ideal' battery is very similar to an 'ideal' bomb.

But I will be able to play on the internet longer so a few burns maybe a missing finger or two are just a trade off.

 

[Besoeker]

I hope that this pans out as well. Faster, cheaper energy storage is very useful.

I should note, however, that 'fast charging' and 'safe' are just about mutually exclusive.

Fast charging means low internal impedance, which equates to high short circuit current. The faster you can charge the faster you can discharge, and the faster you can discharge the more damage you can do in a fault. If you think a 9V battery shorted by keys in your pocket is a problem....

And no, I am not trying to dismiss this technology; if it pans out it will be very useful. My point is that the _ideal_ battery is one that stores energy with no losses and can release that energy rapidly with no losses. In the limiting case an 'ideal' battery is very similar to an 'ideal' bomb.

-Jon

Ultracapacitors can do this. But one thing to remember is that faster charging requires more power. For example, charging batteries for EVs takes hours from a domestic supply because of its limited capacity and that would be the case whatever storage technology was employed.

 

[junkhound]

Typical hype in the link, there is no free lunch in physics or chemistry.

I reviewed a Li polymer battery claim 15 years ago, 'inventor' said he could charge a 270Vdc 100 AH battery in 2 minutes from a 120V, 15 A wall outlet. Violation of about every known law of conservation of energy. Ha! Guy used wall outlet to charge a 1000A-hr battery bank, then hooked that in parallel with the discharged 100A-hr battery and called that 'charging from wall outlet'. Probably a 2 cycle battery life at that charging rate.

Charge rate comparison to filling your gas tank.
20 gal of gas into a tank in say 6 minutes
25% efficient car engine
20 gal = approx. 2.5 million BTU, at 25% = 625,000 BTU
divide by 3412 = 183 kW-hrs; or for a 100% efficient 300Vdc electric car battery, 610 Amp-hrs
6 min = 0.1 hours

power supply to charge a hypothetical 300Vdc, 610 A-hr battery in 6 minutes = 1.8 megawatts. Not including losses.

edit ps: there are aluminum 'battery' schemes where a plate of aluminum reacts and is consumed, recharging is sliding in a new aluminum plate, the 'recharge' is done at the aluminum smelter.