[Duncan]

Hi
I use my car on the track - no problems so far

BUT I can't think of any system that is likely to stop an EV fire once it starts - the problem is that the oxidiser is in the battery - so none of the foam systems will do a thing

The way to fix an EV fire is to get enough water to cool it down to stop the reaction - so an on board system is not going to do it

The advice would be - get out of the car and get everything away from the car then wait until it stops

There is not actually much energy there - more like the energy from burning the sump oil than from burning petrol and it won't spread like petrol

 

[Sunking]

As Duncan says, you cannot put out a lithium Battery fire. CO2, Halon, and Dry Chemical are useless. Best option is hope you get out before you burn to death.

 

[dhymers]

Thanks for the replies guys. It does seem that everyone freaks out a bit when they hear lithium batteries, still.

I was reading the SCCA time trial rules and a simple 2lb hand held extinguisher would meet the minumum rule, and just to keep the safeties happy it could be powder ABC based.

I would love to hear about your experiences Duncan, where do you race and who is the sanctioning body ?

I might yet be sold on a firebottle because it makes a bit of sense to me as I can have nozzles directly into the battery box, a hand-held doesn't help much, and yes, I *very much* realize at that point its "all for show".

 

[Duncan]

Hi
I'm just doing some low level stuff Autocross, 1/8th drags - that sort of stuff

http://www.diyelectriccar.com/forum...dubious-device-44370p15.html?highlight=duncan

I would go with the hand held - you won't be able to extinguish the battery - most battery chemistries are VERY HARD to set on fire - but a handheld would be best to put out any other fires

 

[tiger82]

Any normal race car fire suppression system still has it's place in an EV. The flames will be smothered during the time the system is actively discharging. This will at least give the driver time to escape the vehicle. If the battery pack has gone into thermal overload, the only thing that can be done is to tow the vehicle to a safe location and apply large volumes of cooling water directly to the pack until the reaction has stopped. This could be for up to 24 hours.

We worked closely with the Canadian Regulatory Authorities (CACC), turnworkers, and emergency response crews to make sure they were comfortable before our Tesla EV Cobra hit the race track.

Here's a link to a presentation we made to the Motorsport Emergency Turnworkers Association (META) about EV Race Car Safety (scroll down a little bit from the top of the page):

http://meta.bc.ca/wordpress/2017/05/

Our car made a successful debut a couple of weeks ago. We will provide an update to the forum after our next race. In the meantime, here is a brief blurb on the Sports Car Club of BC's main page:

http://www.sccbc.net/

 

[galderdi]

Here in Australia the regulations require a handheld powder extinguisher. But this is only because they haven't wrapped their heads around the idea of an EV racing. The powder would be absolutely useless on the batteries.

So I have the handheld just to satisfy their rule. But I know there is no point ever using it....other than on someone else's car.

I did purchase the smallest water extinguisher with the idea of mounting that in the car as well. But I never did as it is way too heavy (and big). I really should take it anyway and have it sitting by the track just in case.

I also chose Chev Volt batteries because Lithium ION are slightly less risky compared to some of the other chemistries. But also the construction includes a wafer design with layers of alloy and coolant between the cells. My theory is that this construction means each cell has it's own built in extinguisher (of sorts) and reduces the risk of the excessive heat from one cell impacting the next cell. I know it's no garuntee but combined with a decent BMS it seems to be the best option available.

 

[brian_]

We worked closely with the Canadian Regulatory Authorities (CACC), turnworkers, and emergency response crews to make sure they were comfortable before our Tesla EV Cobra hit the race track.

Here's a link to a presentation we made to the Motorsport Emergency Turnworkers Association (META) about EV Race Car Safety (scroll down a little bit from the top of the page):

http://meta.bc.ca/wordpress/2017/05/

Thanks for sharing that. The presentation was good, and I wasn't aware that EVs were specifically addressed in any Canadian race regulations. Unfortunately, the CACC General Competition Regulations posted online are obsolete (the 2016 regs are still posted), and so do not contain the new Section 23.

 

[galderdi]

I have had a couple of discussions with our local first responders at the track. A couple of things they asked for include:

• Some simple notes for first responders attached somewhere on the body of the car. I have had some stickers made up but I am waiting to attach them to my new car.
• Assurance that there are multiple ways to disconnect the HV circuit.
• Emergency cut of switches on the outer extremeties of the vehicle so first responders don't have to reach in to the cockpit to disconnect the HV circuit.

There has also been another discussion. But this one was with event organisers rather than first responders. So I think this was self serving.....They don't want the extra competition posed by EVs. They basically said there will be no connecting or disconnecting of batteries at their event unless conducted by an electrician. I think it is a bit short sighted. If someone tries that on me I will respond with "Plugging your laptop in poses just as much risk, so I guess you won't be able to do that without an electrician either" Plus they are making rules up on the spot which is not on.

 

[tiger82]

I should have added that the CACC regulations regarding electric vehicles were proposed, but have not been adopted in the 2017 GCR yet.

Galderi: The first responder requests look pretty reasonable. Sounds like you've got some work to do with the local organizers.

 

[dedlast]

They basically said there will be no connecting or disconnecting of batteries at their event unless conducted by an electrician.

Any bets on whether they apply that to the 12V batteries all of their cars tote around? And are likely tinkered with on a regular basis?

B

 

[brian_]

The race organizer's view of EV battery work may be unreasonable... but perhaps so is comparing connecting of 12 volt /50 amp-hour batteries with connecting of 300 volt / 80 amp-hour batteries. Both can spark, but there's a lot more energy potentially involved with the EV.

Are batteries often "tinkered with"? Sure, any part of a race car may need attention, and batteries may be removed and replaced for access to other components, or even just for charging.

As a former race corner worker, I would want both the kill switches and clear identification of any HV components.

 

[Duncan]

I would have though the comment

"Well I built the bloody thing" - would answer any questions about getting an electrician to work on your car's batteries

Besides any electrician would know enough to know that he/she would NOT touch something that they were not trained on

 

[Matej]

Instead of worrying about putting out a lithium fire, are there any tried battery enclosure designs and materials that could contain the fire?

 

[tiger82]

Carbon or stainless steel are the least expensive alternatives. A lithium battery fire can reach 600 degC, so you don't want to use aluminum which has a melting point of 660 degC.

 

[John Metric]

For first responders Check out www.NEDRA.com we have had a white paper written by the university of extrication on incident response guidelines.

 

[John Metric]

In electric drag racing we have had several anecdotal stories of fires from the track. I can tell you from our drivers reported experiences the "fires" get worse the longer you delay getting water on the fire. The major thing that delays that is the case design. We have rules about the battery not being in the drivers compartment but some folks stretch that to mean it can be sitting right next to you in the passengers seat or behind you in the rear seat as long as you build an impenetrable box around it. Also we require a firewall and guarding to keep road objects from penetrating the battery box some folks interpret that as having an impenetrable metal wall or case around it. Well that case then makes fighting a fire nearly impossible. For example the electric fox in Europe burnt for two hours on the track and was still smoldering the next morning because even though the firefighters dumped their entire truck of water on the outside of the metal battery box it didn't quench the fire because there was no way to get the water to the center cells.

Alternatively two lithium fires I have been directly told about that started on the drag strip on battery cases that had quick access removable lids or in another case just a perforated lid were extinguished with less than a gallon of water slowly trickled at the direct spot of the case. One case the fire was put out with repetitive bottles of drinking water.

My personal experience is that the pouch cells fail with a puff and fire is not certain in every case. It did happen to me in one case and the fire fighters arrived and I told them to just trickle water on and in about five minutes it was out with no more than about two gallons of water, it probably could have been less but he had an enormous firefighting hose with large brass nozzle that wouldn't turn down to a small stream just a slow river.

We know stories of killacycle shooting flaming 18650cells out the side of his bike as it went down the track. They sort of self extinguished.

The second type of fire is from an object penetration. I don't have any anecdotes of fires from this but I have several near misses where someone didn't have a driveshaft loop and the torque of the electric motor system would have put them in a class of speed that did require it , the driveshaft broke and flopped around penetrating the battery case.
This type of fire could be quite catastrophic as it would immediately involve several cells all at once jump starting the fire.

This whole story of in track fire suppression does not apply to the other comnon type but worst case of race car fire we have heard about a lot where someone is charging a battery without a BMS and one cell row goes dead and they are not in direct attendance and the charger charges all the other cells over their rated max. charge voltage and the pack gets super hot and then ignites and burns their garage down. That's just a violation of several battery operating manual rules all at once. This is usually the worst type of fire but we do not have any reports of this happening at the track. Probably because you are in direct attendance and watching the charging operation. But sadly this is the most common.

That being said I race land speed and they require a 2lb fire extinguisher. I think it's there only for self extricating. Not to fight a punctured gas tank fire for which it would be of little use.

 

[EVElvis]

Hi
Anyone tried this stuff ?:
http://store.evtv.me/proddetail.php?prod=firebane&cat=23

 

[tiger82]

John: Good point about allowing a place for water to enter the enclosure. We had even thought about creating an insertion point with a a sticker beside it that read someting like "In Case of Emergency, Insert Fire Hose Here".

 

[dhymers]

Awesome info thanks John.