Lithium Smithium! Porsche Offering $219-a-Pound Li-Ion Battery as Weight Saver

Lithium Smithium! Porsche Offering $219-a-Pound Li-Ion Battery as Weight Saver

By John O'Dell November 23, 2009

Option Saves 22 Pounds, But Can't Be Used When Temps Drop Below Freezing

We're not quite sure how this ended up on our desk, except that lithium-ion just seems to shout "green" these days so someone though of us.

You've got to strain a lot to see the green tint, though, in Porsche's announcement this morning that it will start shipping certain performance models with an optional lightweight lithium-ion starter battery along with the regular lead-acid battery.

Here's where the real green - "long green" - comes in, we think: The lightweight, long-life lithium battery will cost - hang on - a hefty 1,904 euros.

U.S.pricing hasn't been announced, but the euros translate to $2,850 - if the battery is shipped with a new car when the option becomes effective in January.

If you already have one of the three models and want to add a li-ion battery (available as retrofits starting in February), the cost jumps to the U.S. equivalent of $3,740.

Guess that'll also affect fuel economy - by lightening owners' wallets a bit.

The upside is that the battery, complete with electronic controller, weighs in at just 13 pounds, 22 pounds lighter than the regular lead-acid battery Porsche nornally uses to crank over the starter motor.

We did some rough calculations and figure that the weight savings translates to, at best, a 0.5 percent fuel economy improvement in a 2,811-pound (curb weight) Porsche Boxter Spyder - less in the heavier GT3 and GT3 RS models that also offer the option. It also might add a fraction of a second to lap times in a racing Porsche - although a decent sent of racing tires or a day at driving school could do the same for less.

There's also this: lithium-ion batteries last longer than lead-acid batteries - reducing consumption of raw materials, and are pretty much entirely recyclable and toxin free.

That's the green, as in environmental, benefit.

On the downside, the battery has to be replaced with a regular lead-acid model during the cold months in most places - Porsche's lithium-ion battery won't finction properly at tempuratures below freezing.

So each Porsche shipped with the dual battery package will actually weigh 13 pounds more, adding to the fuel consumption of the ship, train or truck that's bringing it to the dealership.

Gott in himmel!

John O'Dell:  is an AutoObserver Senior Editor. Follow @AutoObserver on Twitter.