|Michael Gilligan||01/09/2021 09:18:10|
18992 forum posts
The latest chapter in the Chevrolet Bolt story makes disconcerting reading: **LINK**
|John Haine||01/09/2021 09:25:34|
|4188 forum posts|
I seem to recall a few huge refinery fires in recent years and I believe the incidence of ice vehicles self combusting is around the same as EVs. If you store a lot of energy in a small volume it's inherently somewhat risky and low probability risks only show up in high volume production.
1214 forum posts
This problem makes me very wary of sitting on top of a massive battery pack in an EV, if you count back a hundred years or more I suppose the same could be said of those pioneers who ventured onto the roads with a tank full of highly flammable petroleum spirit, we accept that nowadays without thinking. It will take a long time though for me to be converted to an EV, mid seventies now so perhaps I will be able to see out my driving years with an old fashioned internal combustion engined vehicle, yes I am a dinosaur. Dave W
|J Hancock||01/09/2021 09:44:15|
|734 forum posts|
It will certainly be 'interesting ' as this EV story develops. People, in general , do not realise each one of those batteries is like a small thermite grenade .
|noel shelley||01/09/2021 09:54:58|
|770 forum posts|
Never mind about the high entensity smoke that might leak out, look into the voltages and safety required for working on these machines, that's what would worry me ! Noel.
|Mike Poole||01/09/2021 09:59:55|
3075 forum posts
I would like to think that extensive crash testing has found how to build a safe battery that can survive a major impact, I wonder how the fire brigade tackle a battery fire which must be rather unpleasant, maybe a battery fire is all over before the fire brigade could possibly get there leaving just the fire consuming the rest of the vehicle to contend with.
|Mike Hurley||01/09/2021 10:04:26|
|185 forum posts|
I recall recently watching a programme on TV (can't remember which channel ) which looked into fires in EV's and showed early vehicles easily catching light and burning furiously - very nasty, + the toxic mass of residue left afterwards. However, the prog went on to say, and demonstrate, how this wouldn't happen in the newer generation of vehicles as " the battery packs now have extensive internal fusing thus preventing problems .... " to be fair, they did demo this by deliberatley shorting on out with a large metal plate - no fire.
I suppose at the end of the day, nothing in the world could be 100% safe no matter how well designed if manufactured faulty.
|Mark Rand||01/09/2021 10:10:43|
|1062 forum posts|
Having been in a petrol Ford Orion (escort with a boot) that caught fire, I can say that when an ICE vehicle gets burning, the fire brigade can't do mutch with it.
|John Haine||01/09/2021 10:12:57|
|4188 forum posts|
Whereas petrol or diesel of course is entirely safe...
Typical petrol car has a tank capacity of 40 litres, the energy density of gasoline is 33.2 MJ/litre so the stored energy is ~1200 MJ. Tesla model 3 battery has a battery capacity of 76.5 kWh so stored energy is 76.5 x 3600s x 1000 Ws or Joules = 275 MJ, about a quarter of a fully filled petrol car. Battery volts is 375, comparable with the peak mains volts. Skills for safe working surely comparable to a domestic sparks - and they aren't so skilled these days in my experience!
4754 forum posts
Saw that with Guy Martin because he didn't want to be melted in a chemical fireball if his electric vehicle record attempt crashed
Eventually he was actively trying to get the newer batteries to burn at least a little but they were having none of it, very impressively safe, almost ridiculous how hard it was to make them even ignite for a few moments
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