Just when the new technology is starting to take off, leave it to the press to try to stop it. This seems like a non-story to me. One caught on fire after being crashed and a garage with a Volt in it caught on fire. The only take away is make sure the battery isn't damaged after an accident. Not unlike a gas tank.
As the guy driving one around the country for a year on the Drive for Innovation, I can say that all we've seen so far is a software glitch. And while we like a good story, we don't want to end up being THE story.
One fresh report on the Mooresville fire has the origin starting away from the cars and the charging station. We are in that area in a couple of weeks and will make an effort to track down the Mooresville FD chief.
Gasoline is essentially allowed to stick around despite its dangers because a) it's been around forever, and b) it's the best we've got so far. Unfortunately (or fortunately, depending on your perspective) batteries will not likely be given the same pass where safety is concerned.
That's good because I don't like the idea of difficult to extinguish lithium fires, nor the idea of accidentally getting electrocuted by my car. I would guess that there's also a toxicity issue if the battery containment is breached.
On the other hand, roads and cars are really pretty hazardous systems all around. They are much safer than a decade or two or three ago, but we really need to hold all of these technologies to a single standard; not make it rougher on something just because its new.
Why does the battery need to be "safed"? No polymer fuses? And I thought cars were using LiFePO4 these days, which don't burn up like Li polymer cells. I'm sure Chevy will work these things out. In the mean time, I will call the car "Chevy Jolt".
Indeed, having this gymongous lithium battery in a car can't be very reassuring.
My mantra in the past has been that these battery powered electrics are not the way to go, and this "safety" issue, which always draws the loudest oohs and aahs, not to mention jaw-jutting indignation, isn't even the reason.
I've read recently about a new approach that makes infinitely more sense to me. Fuel cells running a mild(er) hybrid powerplant. And to take that a step further, an on-board hydrogen separator, that extracts H2 from a hydrocarbon fuel, and then sends that to the fuel cell. (I've proposed this in the past too.)
The difficult problem with fuel cells has been to get high output. So, remove the piston engine from the mild hybrid, replace it with a fuel cell, and you can have a real electric vehicle without the inherent problems of an oversized, very hot, and still inadequate battery. And this should come close to doubling the efficiency of the car, compared with a piston engine carnot cycle design.
I disagree with your statement that a ruptured fuel line poses a greater fire hazard. Lithium battery fires a notoriously difficult to extinguish once they have started. Water or foam are the WORST things to pour on this type of fire because the lithium will tear the oxygen right out of the water molecule. Then you've got lithium AND hydrogen burning.
If the lithium battery is a cobalt or manganese oxide type, then it has the fuel (lithium) and oxidizer (metal oxide) in close proximity to each other. Cobalt oxide based cathodes are especially problematic since the cobalt oxide decomposes above 175C releasing oxygen.
I believe the Chevy Volt batteries use cathodes based on a manganese oxide chemistry and are therefore more stable.
Don't bother me with the facts or any sort of investigation, we want the blaring headlines and superficial sensationalism--that's what's today's media is all about. Plus, it's the TV ratings sweeps period, so this is just the right kind of material they want.
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