What makes lithium, the lightest metal on earth, our best bet for beating oil? If the world is turning to electric cars with lithium-based batteries, will Bolivia (and its massive deposits of the metal), become the next Saudi Arabia? Why has the Chevy Volt taken so much flak while the Nissan Leaf has gotten such a friendly welcome? Seth Fletcher is a senior editor at Popular Science; his new book, Bottled Lightning: Superbatteries, Electric Cars, and the New Lithium Economy, takes an inside-out look at these amazing new power packs and the geo-political issues that will make them live or die.
Full text after the jump.TreeHugger: Seth, you talk about lithium-based batteries as the best way to beat gasoline. What is it about lithium batteries that makes them such a big deal?
Seth Fletcher: Well, the idea of beating gasoline is tricky because it's, of course, going to be very, very difficult to beat gasoline on a pure energy-density basis. In fact, it might not even be possible. Gasoline is 13,000 watt hours per kilogram, today's lithium-ion batteries are about 200, and lithium-air (another really far-horizon but still lithium-based battery) has a theoretical maximum capacity of 11,000 watt hours per kilogram. And that's never going to be reached-the question is, what percentage of that can we get?
Batteries are hard. But lithium is the best basis we've found so far, because of two intrinsic properties. One is that it's the lightest metal: it's the third element on the periodic table. And it's also highly reactive, so reactive that it doesn't exist in nature in its pure form. And those two things mean that you can build a battery-which is just a chemical system-that is more dense with energy and lighter than those based on just about any other element.
So there's a whole spectrum of things you can do with lithium. Some of them we're doing today. Some of them are maybe decades into the future. But in terms of electrochemical energy storage, it doesn't really get any better than using lithium because of those two intrinsic properties.
TH: What would the perfect battery look like to you?
Fletcher: Think about it in terms of what you want your car to do. Right now, a Nissan Leaf can go about 100 miles, and then it takes eight hours or so to charge. What you want, really, is something that can go 500 miles on a charge, at highway speeds, and then recharge in 15 minutes. That's the ultimate goal, so the ultimate battery would look like that.
What would go into that is unclear. With something like a lithium-air battery-if we can ever get them to work-you might get the charge density that it takes to go 500 miles. But one of the problems with them is that they're really hard to recharge, and they actually discharge very slowly, too. So, what other kinds of things can you build into the system to make it a highway-worthy car? How are you going to recharge it in 15 minutes? That's super challenging. And it might involve building in ultracapacitors. It might involve pairing a bunch of different technologies together. It probably will involve something we haven't even really thought of quite yet, or some clever new approach.
But that's the goal. The ultimate goal for the battery is to match the energy density of gasoline. And by that I mean the usable energy density, because with a gas car you're only getting a fraction of the energy that's in that gas.
TH: Where does lithium come from, and what are the issues associated with getting it?
Fletcher: The majority of the lithium today that's used in batteries comes from a series of salt flats in the high-altitude deserts of a region nicknamed the "lithium triangle," because so much lithium comes from there. It's where Chile, Bolivia, and Argentina meet. The Andes mountains sort of splits this region. And in the high-altitude Atacama Desert in Chile there's a salt flat called the Salar de Atacama. That's the world's richest single source. "Fruitful" would be a better term, actually.
There are two companies with operations on that salt flat. Together, they provide about half of the lithium carbonate in the world market every year. One of them is called SQM; one of them is called Chemetall. There are some deposits in Argentina. There is a giant deposit in Bolivia that are undeveloped and don't look like they're going to be developed anytime soon. But then there are a lot of other places around the world where you can get it, too. There are North American deposits. There's a lot in Australia and China. There's some on every continent, in fact. There's no shortage of lithium. It's just that it hasn't been developed. It hasn't been used very much in the past.
Lithium has historically been pretty comprehensively ignored by mining companies, who are more interested in really valuable stuff like gold and silver and uranium. It's just within the past few years that mining companies and trading houses and large corporations have started looking at it as something that they might want to really tap into. And what they've found is that there's a lot of it around the world, but building the mines to get it out is going to take some work. But there's actually a lot of it available right now, and for the foreseeable future there's plenty.
TH: We read in the media about how we will become beholden to the major lithium-holding countries the way that we are to Middle Eastern countries that hold a lot of the oil. Is that not really as scary as some people would make it sound?
Fletcher: It's not. It's not even remotely as scary as people make it sound. The big scare for a while was Bolivia; how Bolivia's going to be the new Saudi Arabia. Well, Bolivia has a massive deposit, but the large-scale roll-out of electric cars, even if we're talking about millions of cars, just does not require their deposit. It just doesn't.
Chile is a friendly country. Argentina is a friendly country. Australia is a friendly country. I don't think we have to worry about any of those becoming our new overlords anytime soon. And then, if they did-say, all those countries turned on us suddenly, which is so unlikely as to be almost comical-we have big deposits in North America, too, in particular in northern Nevada.
There are two main things to keep in mind here. One is that lithium isn't burned when you use it. It's a metal that goes into building a machine that stores energy. That energy is generated by other means, ideally from renewables, realistically from anything from natural gas to coal to hydro-power or nuclear.
But the other thing to keep in mind is that there has been an ulterior motive behind the spread of a lot of the scare stories about dependence on foreign lithium, I think at least. I've seen a quote by the chief economist for the American Petroleum Institute saying, "Well, you have to keep in mind: a lot of things that are going to go into these batteries are going to come from foreign countries, and we don't want to trade dependence on foreign oil for something else." It's just a misleading argument. It's not a scary situation.