The Battery technology thread - How will EVs be powered?

[randyd]

Originally Posted by NeilBlanchard

http://www.npr.org/2012/03/02/147787...oing-and-going

Thanks Neil!

There are a lot more facts here:
http://web.mit.edu/newsoffice/2009/liquid-battery.html

Originally Posted by DonaldSadoway

the new concept is like an aluminum plant running in reverse, producing power instead of consuming it.

[PatQ562]

Many comments agreed what a lame report the first one was. The entire interview deals with how a storage battery can store daytime solar power and release at night (duh) without a SINGLE WORD about the construction or advantages of the actual battery, other than the implication that it's intended for stationary and presumably continuous duty. Golllly! Huell Howser could have done better.
(edit) The second reference is better - it describes a gravimetric cell, with a molten metal anode, molten salt electrolyte, and lighter molten metal cathode, the trick being to find three constituents with different weights that remain in their layers naturally, remain stable, and store lots of energy. No tricky separators or plates, just bulk quantities of low cost materials (and a container), all at 700C. At utility-grade sizes, the heat lost won't be much compared to the energy stored. Best suited for large stationary applications where the cell is constantly in use. The utilities need cheap and stable above all else. Not a good candidate for mobile use.
Pat Q

[palmer_md]

Another supercapacitor. It will be interesting to see where this leads.

http://www.rsc.org/chemistryworld/Ne...rcapacitor.asp



http://www.rsc.org/chemistryworld/Ne...r/25090802.asp

[randyd]

Originally Posted by palmer_md

Another supercapacitor. It will be interesting to see where this leads.

http://www.rsc.org/chemistryworld/Ne...rcapacitor.asp

Upgrading to Blu Ray? Donate your DVD player to UCLA!

(Just kidding!)

I found the video from UCLA very informative:
http://www.youtube.com/watch?v=_oEFwyoWKXo

Rice university is also working on turning graphene oxide into graphene using lasers:
http://www.youtube.com/watch?v=3O4YV0mrkfQ

[chijayhawker]

I see both palmer_md and randyd beat me to the punch, but here is another link to the article about the supercapicitor:
http://www.sciencedaily.com/releases...0315152524.htm

But to add to the conversation, here's why Hydrogen Fuel Cells will unlikely be a true alternative fuel option (two separate articles):
http://www.sciencedaily.com/releases...0315110407.htm

http://www.physorg.com/news/2012-03-...potential.html

[smilingcat]

The 2nd and 3rd article use of PEM abbreviation is bit confusing. PEM also stands for Proton Exchange Membrane. The thing to keep the anode and cathode separate, and its through this membrane that hydrogen ion (proton) flow through while electrons flow through an electrical circuit.

Anyway, regarding hydrogen fuel cell, I'm really against hydrogen fuel cell for cars and here are some of my pet peeves.

1. Hydrogen production is expensive and not really green.
A. electrolysis is not very efficient and power hog.
B. you can produce hydrogen using reformers by "cracking" methane or natural gas. This produces carbon monoxide and carbon dioxide. Again conversion efficiency isn't all that great and you'd be better off burning the gas to generate power directly for the same amount of CO and CO2 produced.

2. Hydrogen molecule is so small it can permeate through thick stainless steel tanks or other metallic tanks. It'll bleed through and your tank would be empty after prolonged storage.

3. Amount of energy that can be stored as compressed hydrogen gas is rather poor even though hydrogen has a very high specific energy. You can't travel too far before you need to refill the tank.

4. Others have considered storing hydrogen in form of ammonia NH4. LD50 toxicity is around 30-50PPM (off the top of my head so someone may want to check). So if you have a leak, you have 50% chance of dying at 30 to 50PPM concentration. Ammonia is reformed using iron catalyst to generate hydrogen gas and nitrogen. It's a high temperature 800C? activity and under pressure. Not all that safe in a moving vehicle.

just my 2 cents.

correction in bold. me bad. Sorry for the confusion.

[randyd]

Originally Posted by smilingcat

The first article use of PEM abbreviation is bit confusing. PEM also stands for Proton Exchange Membrane. \

Um... The second and third links posted by chijayhawker to point to fuel cell articles. If I may put words in his/her mouth, the two articles indirectly point out fundamental problems with fuel cells (other than the ones you listed): low efficiency, high cost, and short fuel cell life.

But don't let that distract you. The interesting bits here are about the supercapacitor with EEStor-like capacity, and what looks like a highly-scalable manufacturing process.

As always, time will tell.

[smilingcat]

And I just remembered another thing about ammonia. If you crack it and burn it, there is no production of CO or CO2, and depending on how one burns ammonia, you can potentially have low NOx emission. Energy density of ammonia is around 50% of gasoline.

Again the problem has to do with toxicity if it ever escapes. Ammonia production using Haber process is bit costly, not prohibitive, but costly.

Ohhh... this reminds me of several other methods of generating hydrogen more "cheaply". If I remembered right, these are research programs at DOE.

This one gives a quick overview of sulfur-iodide cycle and zinc-zinc oxide cycle.

here http://www1.eere.energy.gov/hydrogen...splitting.html

Needless to say the sulfur-iodide cycle, you would have problem dealing with 850C sulfuric acid vapor on your crucible/reactor wall.

Zinc-zinc oxide cycle, there is a thermodynamic problem of water reforming in process of splitting water into hydrogen on oxygen. And the very high energy required to decompose zinc oxide. Zinc oxide is refractory. Required temperature to decompose is around 2000C. There are few material that can withstand such temperature and remain inert.

you can do more search on zinc-zinc oxide cycle or sulfur-iodide cycle and it will lead you down deep into a long dark tunnel.

[Schrodinger]

Originally Posted by smilingcat

Anyway, regarding hydrogen fuel cell, I'm really against hydrogen fuel cell for cars and here are some of my pet peeves.

Same here, and for the same reasons; however...

Originally Posted by smilingcat

2. Hydrogen molecule is so small it can permeate through thick stainless steel tanks or other metallic tanks. It'll bleed through and your tank would be empty after prolonged storage.

There's been some interesting research by the Nobel Laureate who got the prize for Graphene. Not a product, nor a solution as of yet, but this could change the way we understand porosity at this scale and potentially lead to more secure H2 storage. They have a membrane that is 10^10 times more porous to Water than to Hydrogen.

http://www.rsc.org/chemistryworld/Ne...e-membrane.asp



Then again, the membrane seems better suited to making more efficient water filters, which is excellent as well.

[randyd]

Originally Posted by Schrodinger

Same here, and for the same reasons

I'll jump on that band wagon too.

Originally Posted by Schrodinger

but this could change the way we understand porosity at this scale and potentially lead to more secure H2 storage. They have a membrane that is 10^10 times more porous to Water than to Hydrogen.

http://www.rsc.org/chemistryworld/Ne...e-membrane.asp

Indeed interesting from a material science point of view. The membrane of graphene oxide proved permeable to water but not gaseous Helium (or Hydrogen).

I know it will never happen, but I do wish science reporters would be more careful. This one uses graphene and graphene oxide almost interchangeably.