MSP & garage fire!

[Dzlchef]

4 hours ago, null said:

Really scary, thanks for sharing. Hope you get past the anguish.
It might be worth having thread about what to do in case hell is loose, other than (on top of) call the fire department.

For example:
whether to stay around trying to control the fire, or if the fumes are too toxic.
Other than using an extinguisher, could spraying it with water help cooling it.
If there is any point in trying to isolate it with a fire blanket.
How long to expect it to last..etc..

Of course prevention is best, but in case shit hits the fan it's better to know what to expect and how to act. Especially for people who live in flats and dont have separated areas like garages this is scary.

edit: not to derail anything here, maybe I should move this to separate thread..

 

That's a great point. When my family heard the popping sound, they quickly investigated and upon opening the internal garage door saw the issue. My dad quickly opened the outer door, went inside to grab the ABC extinguisher and came back within seconds. He sweeped the wheel and wall, putting out the fire. He then moved my electric car which was plugged in and charging directly next to the wheel. After everything was clear, he pulled the wheel out of the garage. My wife called 911 upon first learning of the incident and the fire department was onsite with 3 minutes. When they arrived the fire was out and garage wall cooling, no hot spots. 

I attribute our good fortune to the quick action of my father. He assessed the situation quickly. He knew exactly where the fire extinguisher was located, which was very close, and it was the correct ABC solvent. He knew how to use the extinguisher and the fire department was contacted immediately. 

I think we can all learn from those specific points. In later discussions, I learned that neither my mother or my wife, both who were home at the time, knew how to use a fire extinguisher. 

Questions to ponder:

Do you have proper fire extinguishers, and close?

Does everyone in the family know where they are located?

Does everyone know how to properly use an extinguisher to put out a fire?

Lastly, do you have a spot to meet up in case of a fire, like the mailbox, etc.? There was an incident in California where all family members exited a burning house but the husband out back and wife in front, both thinking the other didn't make it out and both went back to save the other and died. Sad, but we can learn from that mistake and plan accordingly. 

This incident has got me thinking about all the what-ifs and making sure we have a good plan moving forward.

Hope this helps folks!

Edited November 24, 2020 by Dzlchef

[AtlasP]

Earlier this year I started a thread to discuss fire extinguishers, here: 

 

Still probably a good place to continue fire-extinguisher-specific discussion.

Edited November 28, 2020 by AtlasP

[redsnapper]

when u hv doubts on batt pack sequester the demon in a lobster pot until proper disposal is possible! ideally dissassembly of pack to salvage good cells is best but then u gotta build a new pack - not for the faint of heart!

 

 

[Simply_Striking]

13 hours ago, ShanesPlanet said:

How odd. Derail for sure, but I'm just curious if they quit having that feature enabled, or quit using a bms that monitors it? Was the bms needed to check so many locations, causing more failures, or was it simply cheaper to not incorporate. Maybe it still monitors it, but they simply don't want the user to access it? Lots of questions, but I just find it odd when a seemingly 'safety' feature gets changed/removed/omitted.

Take this with a lot of salt, as it is my opinion based on actions Future Motion have been making in the past. I think it is to discourage people from/fixing, or even swapping out bad battery packs without going through future motion. In the newer models, you cannot even switch modules between the same hardware boards, like motor hubs, battery, BMS ETC..

[Marty Backe]

6 hours ago, null said:

Really scary, thanks for sharing. Hope you get past the anguish.
It might be worth having thread about what to do in case hell is loose, other than (on top of) call the fire department.

For example:
whether to stay around trying to control the fire, or if the fumes are too toxic.
Other than using an extinguisher, could spraying it with water help cooling it.
If there is any point in trying to isolate it with a fire blanket.
How long to expect it to last..etc..

Of course prevention is best, but in case shit hits the fan it's better to know what to expect and how to act. Especially for people who live in flats and dont have separated areas like garages this is scary.

edit: not to derail anything here, maybe I should move this to separate thread..

 

Fire blanket!  This is intriguing. Might this be an effective way to store our wheels? Throw one of these blankets over the wheel to keep wherever you're storing the wheels from burning down? I need to investigate these blankets more.

[alcatraz]

It's amazing that we still don't have individual cell group monitoring built in by now.

[.....]

7 minutes ago, alcatraz said:

It's amazing that we still don't have individual cell group monitoring built in by now.

Rural Kansas won't put in railroad crossing lights in most places until AFTER someone dies... I am not surprised at all with euc's, as these things cost money to implement. Cost is always a factor. Some industries more than others. With every increase in complexity of a circuit, comes more responsibility on the parts chosen and the way it is designed. Given a long enough timeline of profits, we will slowly see more and more quality be implemented.... I hope!

[alcatraz]

1 minute ago, ShanesPlanet said:

Rural Kansas won't put in railroad crossing lights in most places until AFTER someone dies... I am not surprised at all with euc's, as these things cost money to implement. Cost is always a factor. Some industries more than others. With every increase in complexity of a circuit, comes more responsibility on the parts chosen and the way it is designed. Given a long enough timeline of profits, we will slowly see more and more quality be implemented.... I hope!

True. It would be very cheap to put probe points on the packs though.

[.....]

1 hour ago, alcatraz said:

True. It would be very cheap to put probe points on the packs though.

And even cheaper to buy quality screws in bulk.... yet here we are.

Edited November 25, 2020 by ShanesPlanet

[Tawpie]

I'm by no means an expert but I spent about 15 years designing battery powered devices and in the process developed a healthy respect for the amount of energy stored in these batteries. Consider the following rough estimation:

1 WH = 3600 Joules, so a 1000 WH EUC battery holds 3.6 MJ of energy. Wikipedia says a stick of dynamite is roughly 1 MJ and if so a 1000 WH EUC battery contains the energy equivalent of three and a half sticks of TNT. My 16XS's half assed battery is 2.8 sticks of boom. You don't want to let that energy out too quickly.

Back in the day, rechargeable cells had two safety mechanisms in each cell: a fuse that would open circuit if the current pulled from the battery was too great (thus cutting off the current flow), and a thermal 'fuse' that would also cut off current flow if the temperature got too high. The idea was to prevent the battery from discharging too rapidly because rapid discharge causes the battery to self heat, and at some point an overheated cell will start to a) vaporize the liquid electrolyte which increases the pressure inside the cell which left unchecked will cause rapid disassembly with loud report and b) melt things like the separator that keeps the reagents from combining at will. If the reagents do combine at will, that causes a rapid energy release which can't do any "work" like power a magnet to turn a wheel so it becomes heat which makes the battery hotter which makes things boil and melt faster which... "thermal runaway" is the common term. Once thermal runaway has started the cell will either catch fire or burst, typically both in quick succession. Stopping the current flow (the two safety circuits) is supposed stop the chemical reaction that creates electricity which should stop the self heating but if thermal runaway is already happening the safety circuits don't matter anymore.

The thing about a thermal runaway is that the result is extremely hot and it will keep getting hotter until it runs out of reagents. You're converting the energy of several sticks of dynamite to heat over the course of a few minutes. The fire itself initiates a chain reaction by heating the other cells in the pack so they individually reach thermal runaway and you effectively have to wait until the energy in the entire pack is used before it really starts to cool down. Water keeps the things near the fire from igniting, but the core of the fire may be so hot the water is vaporized before it reaches the base of the fire and thus it can't cool the fire's core. Furthermore, the core of the fire is a chemical reaction that is recreating any heat lost to the water—unless you can drown the thing in enough water to absorb all of the heat being produced (immerse it in a large body of water), it'll keep getting hotter.

All that said LiIon cells are made, used and destroyed by the gazillions with few newsworthy use cases. Their track record is pretty good when they and their surrounding circuits and enclosures are properly designed, manufactured, and used. But as hard as they try, all the cells can't all be perfect and spectacular failures will happen. It's kind of like a 10,000 km rider going 20 km/hr and crashing after hitting a 10 mm bump on the pavement—probably never ever happen. Until it does.

SIDENOTE: 3.5 liquid ounces (0.0273 US gallons) of automotive gasoline has the same energy as a 1000 WH battery... that's why we've gotten pretty good at dealing with gasoline. And are still learning with batteries.

Edited November 25, 2020 by Tawpie
wordsmith (see, I told you i can't help it)

[mrelwood]

48 minutes ago, Tawpie said:

I'm by no means an expert but I spent about 15 years designing battery powered devices

Blimey, what DOES it take to become an expert nowadays?!? 

[Tawpie]

In aerospace, the joke was you were an expert if you were more than 50 feet from your desk. I never got that far. 

[hyperair]

I did some amount of research (read: googling) on the topic during the months leading up to the great Singapore EUC ban.

Some of the useful resources I'd found were:

• https://www.youtube.com/watch?v=1wcLVfwd8mk (an hour-long lecture about fighting li-ion fires at what looks like a fire-fighting conference of some sort)
• https://www.youtube.com/watch?v=vS6KA_Si-m8 (practical evaluation of various approaches to extinguishing laptop battery fires, which are relevant to EUCs because they share similar characteristics (battery is not easily accessible even when it catches fire, etc.)
• https://www.sciencedirect.com/science/article/abs/pii/S2405829716303464 (Thermal runaway mechanism of lithium ion battery for electric vehicles: A review)

Not everything was relevant, but these were the highest quality content I'd come across for dealing with Li-ion fires.

My takeaways from going through these were:

• Li-ion batteries undergoing thermal runaway generate their own oxygen, so smothering/depriving the battery of oxygen does not stop thermal runaway
• Smothering potentially traps heat, which raises the temperature of the battery pack even more, which causes the thermal runaway to be more likely to spread from one or a couple of cells to the whole pack. If you use a fire blanket, then what you'll do is prevent the fire from spreading to other things, but prolong the fire.
• The best way to stop thermal runaway is to remove the heat. This means that you either let it completely burn out (heat dissipates to the environment anyway, and no new heat is produced because fuel runs out), or you actually manage to cool each cell down back to room temperature.
• Water is great at removing heat and also great at getting into the battery, or at least close enough to draw heat out of the pack.

Some of the difficulties involved with putting out a Li-ion fire are related to the fact that the cells are buried inside a battery pack, which is itself buried deep inside the wheel. So, If you can get it out of the wheel, do so, then pour water into the battery compartment. Otherwise, find a large body of water, and drown your flaming wheel in it. Watering a wheel doesn't really work because you can't get deep enough (EUCs are kinda splash proof anyway).

Extra notes regarding water and Li-ion cells:

• Li-ion cells do not contain much elemental lithium and will not react with water to create a huge explosion
• During a thermal runaway, you've got an internal short circuit with much lower resistance than water inside your cell anyway, so don't worry about the water creating a short circuit and making things worse
• The risk of electrocution from this is very small as long as your wheel is not plugged into the charger because you're unlikely to close the circuit with the wheel.

TL;DR for a fire:

1. Get the wheel outside, away from anything else that can burn.
2. Get access to the battery if you can
3. Drown the battery, or the whole wheel if you can't get access to the battery
4. Leave it until the fire is out, and then leave it for another day or so

[null]

Thanks for the added details @Dzlchef , nice to hear the ABC extinguisher managed to get the fire out.

[redsnapper]

8 hours ago, alcatraz said:

True. It would be very cheap to put probe points on the packs though.

Probe points not needed - the BMS are already setup with access to  individual cells (or how would it do balancing?) - if u take a pack apart you can access individual cell health directly on the bms but (at least for EUC) no manufacturer has taken the trouble to get a BMS/controller interface that reports this data via the firmware. As I write this I am remembering threads where people have posted data on individual cell state so I am suddenly wondering if I am out to lunch? Maybe the api gurus can confirm if this is simply a case of firmware not reporting or actually no data from bms?

[bcarp]

1 hour ago, hyperair said:

Drown the battery, or the whole wheel if you can't get access to the battery

Thanks for you very helpful points. Does this one matter whether it's fresh water or salt water? In terms of safety obviously (not rusting).

[meepmeepmayer]

12 minutes ago, bcarp said:

Does this one matter whether it's fresh water or salt water? In terms of safety obviously (not rusting).

The idea is to cool the battery down. So any fluid that is not flammable is good.

The electrolyte in the cells ignites at a certain temperature. You want to prevent further cells from combusting due to their neighbor cells burning, you do that by keeping them cooler than that temperature by conducting the heat away with your fluid.

[BFE Duke]

6 hours ago, hyperair said:

My takeaways from going through these were:

• Li-ion batteries undergoing thermal runaway generate their own oxygen, so smothering/depriving the battery of oxygen does not stop thermal runaway
• Smothering potentially traps heat, which raises the temperature of the battery pack even more, which causes the thermal runaway to be more likely to spread from one or a couple of cells to the whole pack. If you use a fire blanket, then what you'll do is prevent the fire from spreading to other things, but prolong the fire.
• The best way to stop thermal runaway is to remove the heat. This means that you either let it completely burn out (heat dissipates to the environment anyway, and no new heat is produced because fuel runs out), or you actually manage to cool each cell down back to room temperature.
• Water is great at removing heat and also great at getting into the battery, or at least close enough to draw heat out of the pack.

 

I'm thinking the wet blanket technique? Cover it with fire blanket, then hose it down? Prevents spread and cools the pack down through waterboarding. 

[Unventor]

20 hours ago, Dzlchef said:

That's a great point. When my family heard the popping sound, they quickly investigated and upon opening the internal garage door saw the issue. My dad quickly opened the outer door, went inside to grab the ABC extinguisher and came back within seconds. He sweeped the wheel and wall, putting out the fire. He then moved my electric car which was plugged in and charging directly next to the wheel. After everything was clear, he pulled the wheel out of the garage. My wife called 911 upon first learning of the incident and the fire department was onsite with 3 minutes. When they arrived the fire was out and garage wall cooling, no hot spots. 

I attribute our good fortune to the quick action of my father. He assessed the situation quickly. He knew exactly where the fire extinguisher was located, which was very close, and it was the correct ABC solvent. He knew how to use the extinguisher and the fire department was contacted immediately. 

I think we can all learn from those specific points. In later discussions, I learned that neither my mother or my wife, both who were home at the time, knew how to use a fire extinguisher. 

Questions to ponder:

Do you have proper fire extinguishers, and close?

Does everyone in the family know where they are located?

Does everyone know how to properly use an extinguisher to put out a fire?

Lastly, do you have a spot to meet up in case of a fire, like the mailbox, etc.? There was an incident in California where all family members exited a burning house but the husband out back and wife in front, both thinking the other didn't make it out and both went back to save the other and died. Sad, but we can learn from that mistake and plan accordingly. 

This incident has got me thinking about all the what-ifs and making sure we have a good plan moving forward.

Hope this helps folks!

I used to act as firewarden when working in a UK call centre. I saw a film from a soccer stadium fire during TV transmitted game in our training. This video still to this day has a scare to my bone. I don't recall how many that died in that fire. The short answer is way way too many. 

But the points you raised in this post I quated really is a sledge hammer on the nail. 

It is any house hold should know and train for. We might do it at work or at the schools as kids. But it is so so easy to forget our home as this is normally our "safe/familiar" place. 

One thing with an fire you need to be very careful. It goes so fast that many get taken by surprise. And you have both smoke/gases that can be extremely toxic and the heat that kills. On the stadium fire the last person to die was a police officer at center of the soccer field (about 50m from the flames) none could get to him due to the heat. And that was an open stadium. In a room heat and smoke do not escape it only build up. 

Sorry for the post of doom. But it is something I think we need to respect. Fear maybe not. Being prepared, yes absolutely. 

I have long time back stopped charging at night and when not around my wheel. I use a smart wall plug to cut the power. I know that is not helping in this OP case. But some steps can be taken. 

Thanks to OP for highlighting his experience that we all hope never happens. 

[AtlasP]

[deleted--others below just clarified my answer better]

Edited November 25, 2020 by AtlasP

[Planemo]

26 minutes ago, AtlasP said:

I believe this is false. EUC BMS's to date only do balancing by trickle charging through each pack of cells as a single serial loop. I know of no EUC BMS with leads to each cell separately.

Yep, correct. The smallest group or 'string' is usually 3, 4 or 6 cells depending on the make/model of EUC (and done in parallel, not serial). In answer to amelanso, yes there is balancing to an extent, but only to each string. Even Ninebot (the best factory cell monitoring we have) can only read each string voltage. Still, that's a lot better than any other manufacturer which only sends the whole pack voltage. Thinking about it, maybe the V11 sends string voltage as well..? Not sure as I haven't followed the V11 that much.

Edit: Oops Chriull beat me to it lol

Edited November 25, 2020 by Planemo

[winterwheel]

23 hours ago, Marty Backe said:

If I had one or two wheels I would store them in such a cabinet. What to do when you have a dozen 

I have 13 wheels in my garage right now, they are stored in a custom-built wooden box, not ideal, let me know if you think of something. 

Edited November 25, 2020 by winterwheel

[Chriull]

9 hours ago, amelanso said:

Probe points not needed

Ks18Xl for example have a connector with access to each cell in one corner of the BMS.

Quote

- the BMS are already setup with access to  individual cells (or how would it do balancing?) 

Exactly.

At around 4.2V they activate the "bleeding" resistor in parallel to this cell group.

Additionally at around 4.25V it cuts off the charging input.

Quote

 Maybe the api gurus can confirm if this is simply a case of firmware not reporting or actually no data from bms?

Ninebots (z10) BMS reports single cell group voltages to the mainboard and zhe firmware forwards it to the app via bluetooth.

KS and GW BMS do the single cell overvoltage monitoring and balancing, but do not report anything to the mainboard - so the firmware cannot report any voltage to the app...

Veterans BMS maybe reports cell undervoltage?

Edited November 25, 2020 by Chriull

[redsnapper]

8 minutes ago, winterwheel said:

I have 13 wheels in my garage right now, they are stored in a custom-built wooden box, not ideal, let me know if you think of something. 

Abandoned missile silo?

[winterwheel]

1 hour ago, amelanso said:

Abandoned missile silo?

It gets worse as I have three more coming in the next few weeks. 

I'm planning to build some sort of compartmented box that will isolate the wheels from each other, trying to imagine what sort of materials one would use for that.

My oldest wheel, the V5F, loses 25% of its charge within 24 hours of charging up to 100% but then holds steady after that. This thread has got me a bit nervous about that one.