Thursday, November 24, 2005

The Lithium Economy

An article in Technology Review interviews Donald Sadoway, who holds 13 patents and has published more than 100 papers on the future of batteries and the all-electric car.

Sadoway dismissed the much vaunted hydrogen economy, saying that the future is in lithium batteries.

I don't believe in fuel cells for portable power. I think it's a dumb idea. The good news is: they burn hydrogen with oxygen to produce electricity, and only water vapor is the byproduct. The bad news is: you have to deal with molecular hydrogen gas, and that's what's stymieing the research and in my opinion is always going to stymie the research.

That's why I don't work on fuel cells. Where's the infrastructure? Where are we going to get hydrogen from? Hydrogen is a molecule, it's H2. To break it apart, to get H+, you've got to go from H2 to H, and that covalent bond is very strong. To break that bond you have to catalyze the reaction, and guess what the catalyst is? It's noble metals -- platinum and palladium. Have you seen the price of platinum? Lithium [for lithium ion batteries] is expensive. But it's not like platinum. Lithium right now is probably $40 a pound. Platinum is $500 an ounce. If I could give the fuel-cell guys platinum for $40 a pound, they would be carrying me around on their shoulders until the day I die.

While electric cars have thus far been held back because of their limited range between recharges, Sadoway believes that we could easily double the energy capacity of present batteries, and that much larger increases in power are within the realm of possiblity.

The fantasy of all fantasies is chromium. If we could stabilize chromium [as a material for battery cathodes] and I could...give you a battery with 600–700 watts per kilogram [of energy capacity] with reasonable drain rate, that says good-bye hydrogen economy.

Lithium batteries powered by solar rechargers hold out the possibility of a much greener future.


Post a Comment

<< Home