Would a fuel cell powered car produce a larger explosion than a car with a combustion engine?

Question

I recently did some research on the new Honda FCX vehicle. In looking at the layout of the car i noticed that, in the rear, there is a tank of highly compressed hydrogen. Obviously this is necessary for a fuel cell to function but, in the event of a fire or a crash wouldn't this be similar to the Hindenburg? Is the gasoline tank of an ordinary car as prone to explosion? Would tanks of comparable size produce a similar explosion or would the hydrogen tank be even more volatile?

Answer 1

Actually hydrogen is less dangerous than gasoline. The only thing that's dangerous about hydrogen is that it has to be stored under very high pressure, which could result in the hydrogen tank violently flailing around if it breaks open. However due to the location of the tank, that isn't likely.

And I'd like to point out the Hindenburg didn't explode at all. In fact it's a great example of how safe hydrogen is. The burning you saw was the cloth exterior on fire. There was no explosion.

Answer 2

Hydrogen is the most explosive gas on earth. The hydrogen atom is the smallest and will leak through anything.

Answer 3

The outer cloth on the Hindenburg was painted with a material that is now used as a rocket propellent- no wonder it burnt well.    Hydrogen doesn't have nearly the energy equivalent per pound that gasoline has, so it wouldn't put out so many BTU when burnt.   It would cause more damage from the explosion sending flying metal parts than from heat generated.    Not all fuel cells run on pure hydrogen.   Some use natural gas and seperate the hydrogen out, while others can use heavy fuel oil which is hard to get to burn no matter what.     It has to be heated just to make it flow.

Answer 4

I don't have an answer - The Honda web site for the FCX says the car is "safe" - I'd like a much more detailed answer, crash test results, and a clear explanation of why each of these cars is not a Hindenburg waiting to happen

Answer 5

Seeing as cars rarely catch fire (and even more rarely explode) that is not something I am particularly concerned about. The hydrogen also has to be present at a particular range of concentration to explode and due to its lighter-than-air nature rises and dissipates much more quickly than gasoline.

BTW, there is evidence that the Hindenburg disaster was caused not so much by the hydrogen as the metal coating on the exterior.

Answer 6

Not really. The H would burn off explosively and be gone in a fraction of a second. Gasoline burns as it vaporizes, thus it burns longer. The fire you see of the Hindenburg is mostly the cloth and structure burning. The H was gone long before the vehicle hit the ground.

Also think of this. There are literally thousand of ascents a month just in the US. How many of them result in any type of fire?

Answer 7

There is a danger with any highly compressed gas in an accident situation.   Hydrogen will make it a bit more dicey, since it is highly combustable.  I think much of the problem with the fuel cell vehicles was in creating an impact resistant container.

Of course, car fires now are not that common either.  And modern cars do not really explode.  They may occasionally burst into flame in a serious accident, however.

Long story short; I guess we will find out when they start having accidents.