Enabling Responsible Hoonage – Lithium Batteries

asked for the gen about claims he’d seen that “the environmental impact of making all those lithium batteries ,… far outweighed the disadvantages of drilling up oil and burning it.” And like anything these days, you can’t just say “this car runs off electricity so its environmentally friendly”, you’ve got to look at where the electricity comes from and the environmental cost of making the car, the batteries and everything else.

The short answer: vehicles running off lithium batteries are much, much better than vehicles burning petrol.

There’s two points in reply. Firstly, most of the energy cost of a car comes when its being used, generally 80% or more. So its almost always worthwhile making a fancier car that uses less fuel. Secondly, if we’re running the car on electricity, then we can make that leccy using wind, hydro, geothermal, even nukes, and our carbon emissions go down by orders of magnitude.

(And even in the worst case, when we’re getting that electricity by burning coal, its more efficient to burn all that coal in one big station, turn it into electricity, transmit it and charge batteries, than it is to burn petrol in a million tiny little engines, coz big heat engines are so much more efficient.)

The big argument on lithium is about whether we’ve got enough of it, i.e. are we going to hit Peak Lithium. And the quick answer is: no.

Not the quick answer
All this parlaver comes from one article, and its a fairly interesting article by William Tahil. However, when it comes to the crunch, it makes some very pessimistic assumptions and some of the numbers in it are just plain wrong.

The Trouble with Lithium
Implications of Future PHEV Production for Lithium Demand
– anyone who makes subtle references to ‘ favourite SF book can’t be all bad

The most relevant error is that Tahil overestimates the amount of lithium required for an electric car, by a factor of five. Whoops.

He dismisses recycling in one paragraph as some future hope. Well, lithium battery recycling is already happening, and will multiply supply by umm… lots. For lead batteries, 95% of the lead is recovered by recycling, that pushes the potential supply up by a factor of 20.

The world lithium supply can do the job and Tihal might be wrong by two orders of magnitude. We’re not rolling in it, and the price will probably go up, but I think we’ve got enough lithium to replace every petrol tank on every vehicle in the world.

(And as usual in these kinds of arguments, Tahil ignores the fact that better technology means better exploration and increasingly affordable extraction from reserves that are currently too expensive to use, so proven reserves will increase. For example, he ignores the fact that there’s round about a billion tonnes of lithium in sea water. Current production is 20,000 tonnes. Yes, we’ll need a better extraction technique than solar evaporation. Tihal considers this source “impractical and unrealistic”. I’d say that we haven’t worked out how to do it yet, coz we’ve never really needed to. I’d guess at some kind of selective ion-exchange membrane. This is not a hard technical problem.)

So please return to your environmentally-friendly hoonage. Anyone found driving at less than the speed limit will be severely sworn at.

3 thoughts on “Enabling Responsible Hoonage – Lithium Batteries”

Leave a Reply

Your email address will not be published. Required fields are marked *