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Just reading about the accident Richard Hammond was recently involved, in an electric supercar. It burst into flames rather quickly apparently, the car makers said it's "complicated" with it being electric. This (codswallop) had me asking why in so far as, we have safety in car features eg. auto inflatable air bags, it should be simple to have an auto circuit breaker/cut iff switch. Btw I have an electronic/electrical background before anyone savages me. I do realise the vehicle was probably an early version, maybe they are cutting corners saving costs.
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Just reading about the accident Richard Hammond was recently involved, in an electric supercar. It burst into flames rather quickly apparently, the car makers said it's "complicated" with it being electric. This (codswallop) had me asking why in so far as, we have safety in car features eg. auto inflatable air bags, it should be simple to have an auto circuit breaker/cut iff switch. Btw I have an electronic/electrical background before anyone savages me. I do realise the vehicle was probably an early version, maybe they are cutting corners saving costs.
I seem to recall reading a while ago that some cars had sensors that unlock all doors if there is an impact (intended to help emergency service access in case of accidents).
Street robbers in South Africa knowing this were smacking front bumpers with baseball bats to open the cars.
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does anyone know what the safety record of these cars is?
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does anyone know what the safety record of these cars is?
Only 8 Rimac Concept Ones were built. Presumably there are 7 now.
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Probably had eco low rolling resistance tyres on it. Otherwise known as expensive ditch finder tyres.
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They use large numbers of LiIon cells which are potentially very very dangerous. You might remember exploding laptops, and people have been killed when a mobile phone battery exploded. In short, a LiIon cell will explode - or more accurately vent with flames - if over-charged, over discharged or shorted. Well made modern battery packs have multiple safety mechanisms, which are designed to prevent over charge and over discharge, making the cells safe.Your iPhone, iPad, Samsung S8 etc all contain LiIon cells, and the number of accidents is very very low as long as you don't buy cheap replacement batteries. Cheap battery packs are often far from safe, as they have poor quality control and oftn lack protection circuits.
Of course if you do crash an electric car, the cells might catch fire due to a short circuit for example. But a petrol tank can explode too. Is it better?
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I fly RC planes. So I know a bit about LiPo batteries.
If the bag gets punctured by steel say a screwdriver..you have a instant fire with lots of smoke. Sometimes they swell burst and catch fire while being charged.
I charge mine in a special safe bag and never leave them unattended.
The thought of having hundreds in the car with me is terrifying.
Welcome to your future.
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I fly RC planes. So I know a bit about LiPo batteries.
If the bag gets punctured by steel say a screwdriver..you have a instant fire with lots of smoke. Sometimes they swell burst and catch fire while being charged.
I charge mine in a special safe bag and never leave them unattended.
The thought of having hundreds in the car with me is terrifying.
Welcome to your future.
Yes,as someone who also flies electric RC planes I can vouch for the dangers these batteries pose. Some years ago I had a new battery burst into flames,destroying itself and two other batteries in the vicinity. Since then i charge them outside and store them outside in a place where a fire would not cause any further damage. These Lipos require a specialised charger and need charging at the correct rate. The mail service will not deliver them through the post,nowadays they are a courier only delivery. Any car using them needs the battery compartment well designed for safety in the event of an accident or incorrect charging. But battery technology is making constant strides towards safety and efficiency.
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At the risk of being ot. I mainly fly ic glow.
But it's a great hobby isn't it. Wot4 with a Irvine53 bliss!
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Well I fly RC helis powered by Lipos. Every example Ive come across of an RC lipo exploding \ bursting into flames has been down to User error, usually while charging or from a short circuited.
Fact is, our lipos are to all intents and purposes covered by a thin plastic outer wrapper and cannot be compared to the batteries in cars. Batteries in (full size) cars are not in a plastic wrapper. They are to my knowledge inside a metal compartment and not easily punctured.
There's an as high a probability that hammond's car would have burst into flames if it the petrol tank had of punctured or spilt fuel (diesel wouldnt burn because it needs to be compressed to ignite) seeing as it had cartwheeled at least once.
I dont believe it's correct to compare RC lipos with the motive batteries used in cars.
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There's an as high a probability that hammond's car would have burst into flames if it the petrol tank had of punctured or spilt fuel (diesel wouldnt burn because it needs to be compressed to ignite).
Not true.
Auto ignition temperature of petrol is 246 C, auto ignition point of diesel is 210 C.
Petrol appears more flammable because its Flashpoint is lower, -43 C compared with diesel's Flashpoint of >52C.
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Speaking to a local fireman who told me that all hybrid and pure electric cars pose a Hazchem alert if involved in a major crash . As well as spillage on the road there is a danger to passengers and attending Firecrew even with gel batteries.
Can anyone confirm this ?
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We have spent over 100 years trying to tame the risks associated with the fuel in internal combustion engines.
Even with cut off switches, and tanks designed to absorb rather than rupture in "normal" accident situations there is still the potential for a serious fire. Safety in design can fail as the product ages and accidents outside design parameners may anyway rupture fuel tanks.
We are at the start of the learning curve with high output, low weight and size battery power for cars. In ten years the desigh, installation and protective technology will almost certainly be different.
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I was reading about another well-known supercar, with petrol engine, that caught fire after a collision and was burnt away to almost nothing (after the occupants had escaped uninjured). What this car had in common with the electric one Hammond was in was a carbon-fibre body.
Edited by Sofa Spud on 03/07/2017 at 19:49
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I was reading about another well-known supercar, with petrol engine, that caught fire after a collision and was burnt away to almost nothing (after the occupants had escaped uninjured). What this car had in common with the electric one Hammond was in was a carbon-fibre body.
Glass fibre bodywork also burns quite readily, it's the resin bonding the fibres which is inflammable. Carbon fibres obviously will burn which glass fibre won't.
I saw a letter in the Telegraph relating to the Grenfell cladding. The writer stated that "aluminium is normally coated with oxide, but if it melts it is exposed to the air and will burn".
Unbelievable ignorance, how does he think aluminium castings are made? (I have personally poured molten aluminium into moulds and I know it doesn't catch fire). Yet one more example of the lack of knowledge of elementary science and technology of the general public, not to mention Oxbridge educated politicians and bureaucrats.
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Aluminium does burn if it gets hot enough according to this paper (PDF) on combustion of aluminium:
www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA425147
So the writer in the Telegraph was essentially correct.
Also many "aluminium" products are made from aluminium alloys of one kind or another and these have varying susceptibility to combustion.
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I think we are overlooking the fact that diesel cars are far less likely to catch fire than petrol cars.
We had a Vauxhall catch fire on our car park and the flames spread to two adjacent cars before finally stopping when it came up against a diesel car. The diesel suffered extensive damage to the tyres and side but didnt catch fire.
For me thats good enough reason to stick with diesel QED. No fires, no leaking chemicals,
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I think we are overlooking the fact that diesel cars are far less likely to catch fire than petrol cars. For me that's good enough reason to stick with diesel QED. No fires, no leaking chemicals,
We're drifting some way from topic, but 'for me' flammability of diesel v. petrol is some way down my priority list. I shall stick with the diesel I have, because I know it uses less fuel than a petrol car would. I do what I can to keep it running cleanly, and so far (9 years) it has cost me zero in unscheduled repairs or maintenance (ignoring the minor collision last Christmas :-) ).
Knowing that my car might act as an effective firebreak in a supermarket car park doesn't figure in my calculations.
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Aluminium does burn if it gets hot enough according to this paper (PDF) on combustion of aluminium:
www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA425147
So the writer in the Telegraph was essentially correct.
Also many "aluminium" products are made from aluminium alloys of one kind or another and these have varying susceptibility to combustion.
Finely divided aluminium, i.e. powder, as used in freworks and explosives will burn, so will iron powder, flour, sawdust and many other substances, my point is that bulk molten aluminium, even at dull red heat, does NOT burn.
Magnesium is a different thing altogether, as shown by its use in incendiary bombs in WW2.
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