

GM Volt Battery to have 8-year/100k miles warranty - MikeCapone
http://www.treehugger.com/files/2010/07/gm-chevy-volt-battery-warranty-8-years-100k-miles.php

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kevinskii
The article is mistaken in interpreting the warranty as a sign of GM's
confidence in their product. GM is offering the warranty because no one will
buy the car otherwise, and they really have little to lose if the battery
turns out to be a turd. They'll either get another government bailout or
declare bankruptcy, which is just what would have happened anyways. Consumers
know this, which is why other car companies won't necessarily feel compelled
to match the warranty.

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curtis
At one point the Volt was expected to use lithium ion phosphate batteries from
A123 Systems (<http://en.wikipedia.org/wiki/A123Systems>), but at some point
they were dropped in favor of a lithium ion polymer battery system from LG
Chem (<http://en.wikipedia.org/wiki/LG_Chem>). I'm under the impression that
commercially available lithium ion phosphate batteries are already good enough
that they can reasonably be expected to last for 8 years / 100k miles.

The most notable tradeoff between the two battery chemistries is that lithium
ion phosphate batteries tend to last longer (maybe much longer), but lithium
ion polymer batteries have about twice the energy density when they're new. If
Tesla were using lithium ion phosphate batteries, they'd only be looking at a
120 mile range on the Roadster instead of 240. Since the Volt is a plug-in
hybrid with only a 40 mile range on battery alone, it seems like lithium ion
phosphate, with its longer life time, would be the ideal choice.

This raises the question of why, exactly, GM switched to lithium ion polymer.
I don't know, nor have I seen any informed opinion about that. My guess, and
this is total speculation on my part, is that a) they didn't think A123
Systems had the capacity to support the Volt, and b) LG Chem made them a deal
they couldn't refuse.

I suspect (and again, I'm just speculating) that GM may be expecting to have
to replace batteries of the first generation of Volts under warranty. I also
suspect that LG Chem will be assuming some of the cost, and that both parties
believe replacement batteries will be substantially cheaper in a couple of
years when they're needed. Finally, I think that GM expects to lose money for
several years on Volt anyway. This is not necessarily bad business -- it will
be years before Volt and other GM electric vehicles will make a major
percentage of their sales. I'm pretty sure Toyota lost money for years on
Prius, and few people think that was a mistake anymore.

