Fire Sensors for electric vehicle garages

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Has someone here ever looked into sensors for garages used for EV's? I know IC engine exhaust may well set off ionization/photoelectric detectors, but this garage has none. (Even the lawn mower is electric.)
 
Open Neutral said:
Has someone here ever looked into sensors for garages used for EV's? I know IC engine exhaust may well set off ionization/photoelectric detectors, but this garage has none. (Even the lawn mower is electric.)
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Siemens markets a system for early detection of incipient Lithium Ion battery fires, but it is definitely slanted to the commercial market.

new.siemens.com

Aspirating smoke detectors (ASD)

Ensuring reliable fire detection in demanding application areas, where earliest possible fire detection is essential and business continuity is paramount.
new.siemens.com new.siemens.com
 
We have used something called a 'heat detector' in residential garages. They tied in with the 120V14/3 smoke alarm circuit.
 
Li-ion batteries can just be dangerous. I've seen a lot of bulged out batteries. Never a spontaneous fire yet, but plenty of OMG.
 
tortuga said:
We have used something called a 'heat detector' in residential garages. They tied in with the 120V14/3 smoke alarm circuit.
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Unfortunately, the only thing the heat detector is good for is notifying you that you need to call your insurance agency to report a total loss. By the time it goes off, the fat lady has sung, done two encores, and left for the after party. The Siemens is a VESDA system tuned for the early detection of LiON combustion particulates.
 
gadfly56 said:
Unfortunately, the only thing the heat detector is good for is notifying you that you need to call your insurance agency to report a total loss. By the time it goes off, the fat lady has sung, done two encores, and left for the after party. The Siemens is a VESDA system tuned for the early detection of LiON combustion particulate
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Not sure it makes much difference given that LiON batteries are very difficult to extinguish. Maybe earlier detection would permit the fire department to prevent the spread to other areas.

I would never have an EV if I had an attached garage. This technology is not really ready for prime time. There are number of large fires from this source everyday.
 
don_resqcapt19 said:
I would never have an EV if I had an attached garage. This technology is not really ready for prime time. There are number of large fires from this source everyday.
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Every day? I think you're off by an order of magnitude, the number of EV fires in 2021 was closer to 36 than 365.

The phenomenon of EV fires while parked (often charging) is certainly an issue. I think ICE cars also have had this issue (e.g. a design defect that allows hot oil to leak onto hot metal after driving), not sure what the rate on that is. And of course ICE cars overall have a much higher rate of catching fire, but that's usually due to an accident or while the engine is running.

It would be interesting to compare the likelihood of a garage fire for a garage used to house only an EV, no flammables (no gas mower, etc) vs a typical garage. I'm not convinced it's any higher, probably lower.

Cheers, Wayne
 
And most of those “36” were involving cars with known battery defects and/or active recalls.
A spontaneous fire in a properly designed, manufactured, and utilized Lithium battery is very rare.
 
wwhitney said:
Every day? I think you're off by an order of magnitude, the number of EV fires in 2021 was closer to 36 than 365.

The phenomenon of EV fires while parked (often charging) is certainly an issue. I think ICE cars also have had this issue (e.g. a design defect that allows hot oil to leak onto hot metal after driving), not sure what the rate on that is. And of course ICE cars overall have a much higher rate of catching fire, but that's usually due to an accident or while the engine is running.

It would be interesting to compare the likelihood of a garage fire for a garage used to house only an EV, no flammables (no gas mower, etc) vs a typical garage. I'm not convinced it's any higher, probably lower.

Cheers, Wayne
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Probably not if you figure e-bike, cars, lawnmowers, etc..
1 a day would probably be an underestimate if figured around the country..
example…
 
wwhitney said:
Every day? I think you're off by an order of magnitude, the number of EV fires in 2021 was closer to 36 than 365.

The phenomenon of EV fires while parked (often charging) is certainly an issue. I think ICE cars also have had this issue (e.g. a design defect that allows hot oil to leak onto hot metal after driving), not sure what the rate on that is. And of course ICE cars overall have a much higher rate of catching fire, but that's usually due to an accident or while the engine is running.

It would be interesting to compare the likelihood of a garage fire for a garage used to house only an EV, no flammables (no gas mower, etc) vs a typical garage. I'm not convinced it's any higher, probably lower.

Cheers, Wayne
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World wide for Li battery fires and not only in vehicles and some very spectacular ones.
 
don_resqcapt19 said:
World wide for Li battery fires
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OK, I'll agree that those occur every day. So do ICE vehicle fires. The relevant question is whether parking and charging an EV in a garage is a higher fire risk than parking an ICE vehicle in a garage; we don't have any data on that in this thread so far, I'd be very interested in a detailed comparison.

Cheers, Wayne
 
wwhitney said:
OK, I'll agree that those occur every day. So do ICE vehicle fires. The relevant question is whether parking and charging an EV in a garage is a higher fire risk than parking an ICE vehicle in a garage; we don't have any data on that in this thread so far, I'd be very interested in a detailed comparison.

Cheers, Wayne
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I don't have an attached garage for my ICE vehicles either :)
When you have manufacturer's telling you not to park in an attached garage after charging, something is going on. Yes that was related to specific probables with their battery, but this is not perfected technology and we have a lot to learn.
 
don_resqcapt19 said:
I don't have an attached garage for my ICE vehicles either :)
When you have manufacturer's telling you not to park in an attached garage after charging, something is going on. Yes that was related to specific probables with their battery, but this is not perfected technology and we have a lot to learn.
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So…..at what point do you define a technology as “perfected”?
 
wwhitney said:
OK, I'll agree that those occur every day. So do ICE vehicle fires. The relevant question is whether parking and charging an EV in a garage is a higher fire risk than parking an ICE vehicle in a garage; we don't have any data on that in this thread so far, I'd be very interested in a detailed comparison.

Cheers, Wayne
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There are two major elements to risk analysis. The first is, how likely is the event to occur? The second is, if it occurs, how bad will it be? So even if EV fires are less common, their severity is higher, because of how difficult they are to extinguish. There is a max/min exercise in here that you could calculate the relative risks of ICE vs EV globally based on number of incidents and total economic loss.
 
gadfly56 said:
Unfortunately, the only thing the heat detector is good for is notifying you that you need to call your insurance agency to report a total loss. By the time it goes off, the fat lady has sung, done two encores, and left for the after party.
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Well sorta, Sure the $1600 Siemens detector is better, no doubt.
Consider though most residential attached garages have a two hour firewall and similar tests show a thermal link activation temperature of a sprinkler at 74°C (165°F) 3667 seconds after they began their test (page 35).
Assuming the heat detector goes off around the same time that could be just enough time to wake you up and get your 2 kids, dog and grandmother out of the house.

Also considering:
  • Manufacturers dont recommend using standard 120V smoke detectors in garages as they are dusty and unheated and thus code has never required them.
  • A heat detector costs about $20, the J-box and a 50' piece of 14/3 probably not much more than $40 at today's inflated prices so for $60 in materials and a few hours of labor just about anyone can add one of these into a standard 120V residential fire alarm system.
 
tortuga said:
Well sorta, Sure the $1600 Siemens detector is better, no doubt.
Consider though most residential attached garages have a two hour firewall and similar tests show a thermal link activation temperature of a sprinkler at 74°C (165°F) 3667 seconds after they began their test (page 35).
Assuming the heat detector goes off around the same time that could be just enough time to wake you up and get your 2 kids, dog and grandmother out of the house.

Also considering:
  • Manufacturers dont recommend using standard 120V smoke detectors in garages as they are dusty and unheated and thus code has never required them.
  • A heat detector costs about $20, the J-box and a 50' piece of 14/3 probably not much more than $40 at today's inflated prices so for $60 in materials and a few hours of labor just about anyone can add one of these into a standard 120V residential fire alarm system.
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OK, yes, it depends on the mission requirements. If you want to get the heck out of Dodge before things get really toasty, absolutely, a heat detector is the way to go. It just won't save the electric vehicle. And you are spot on for the difficulties in using smoke detectors in garages. Smoke alarms/detectors are not listed for use below 32°F. Conventional heat detectors don't care.
 
gadfly56 said:
OK, yes, it depends on the mission requirements. If you want to get the heck out of Dodge before things get really toasty, absolutely, a heat detector is the way to go. It just won't save the electric vehicle. And you are spot on for the difficulties in using smoke detectors in garages. Smoke alarms/detectors are not listed for use below 32°F. Conventional heat detectors don't care.
Click to expand...
 
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