Fire Suppression Stickers

[StealthPhoenix]

i think the solution could be simpler. and im sure many have already stated this, but just in case:

why not just build eucs with flame retardant coatings over all the battery packs? alternately, in lieu of relying on better build by the manufacture, we could just do it ourself, just as those who rely on silicone and...gorilla tape for all repairs and waterproofing.

@314ka4y, @Hsiang what are your thoughts on a UL94 V-0 rating? https://en.wikipedia.org/wiki/UL_94 i ask because i believe i have seen a few products that have this rating and are actually aerosol or liquid products that can be used to coat the entire battery pack.

i work for the govt and have to do annual fire safety and evacuation training myself, but i dont know the safety ratings off hand as its more a tertiary role for me at work, but.....

 

 

flame retardant coatings that anyone can do at home for their battery packs, like some aerosol, is going to be a far better product than a few stickers imho. and if its good enough for an actual car...then surely you can see where i am going with this

[Asphalt]

18 hours ago, StealthPhoenix said:

why not just build eucs with flame retardant coatings over all the battery packs? alternately, in lieu of relying on better build by the manufacture, we could just do it ourself, just as those who rely on silicone and...gorilla tape for all repairs and waterproofing.

 

flame retardant coatings that anyone can do at home for their battery packs, like some aerosol, is going to be a far better product than a few stickers imho. and if its good enough for an actual car...then surely you can see where i am going with this

This is a great idea. Please provide a link to such a product.

[StealthPhoenix]

1 hour ago, Asphalt said:

This is a great idea. Please provide a link to such a product.

@Asphaltif i had used such a product, idve provided the link already.

but ive not used one that i can readily back up.

there is only one product currently that im entertaining https://www.hot-stopl.com/product-details.html

its a flame retardant bag used by the airlines mainly. its pricey though starting at $820USD. but my euc has a lot of space for me to rearrange the battery pack so i can fit it inside this bag. a project in itself though..

..since i am still researching, note the "?'s" in my previous post.

--------------------------

with the stickers suggested, have you tested them under duress? they seem awfully small to stop any fire from the battery packs. but i WOULD consider buying a whole bunch and just lining the whole inside shell with them, or around the entire battery pack...not just one strip.

i dont know, you are the experienced one here. tell us.

---------

edit: i was looking at different fire retardant epoxy/resin products, the bag style products, paints and aerosols etc. https://www.3m.com/3M/en_US/company-us/all-3m-products/~/3M-Fire-Barrier-Plenum-Wrap-5A-/?N=5002385+3293123895&rt=rud

https://www.3m.com/3M/en_US/company-us/all-3m-products/~/All-3M-Products/?N=5002385+8711017+3294857497&Ntt=fire&rt=rs the whole spectrum if we limit it to only 3M.

https://industrial.sherwin-williams.com/na/us/en/protective-marine/products-by-industry/all-products.html?fq=ads_f10004_ntk_cs%3A("Fire Protection")&page=1&tabSelected=product&type=product the 14 fire protection coatings available by sherwin williams

sure they are suited more toward building applications, referring to intumescent coatings and cementitious coatings, but if it can aid in fires for larger structures, despite battery pack fire falling into class bcd territory, those compounds could help. as well, polycarbonate fire retardant shells could be used in the manufacture of the eucs, or we enterprising individuals can take it upon ourselves to make such a product and then....link it for you.

but this is still only basic research at this stage

Edited January 29, 2021 by StealthPhoenix

[Asphalt]

@Hsiang nice coverage on the recent Gotway fires.

I've been considering storage units as well, but that just moves the problem to another location - unless the storage facility uses fire-proof containers.

There is no way PEVs are going to gain mass adoption if people feel like they're living with ticking time bombs. Can you imagine if every household had multiple PEVs? Even a 0.001% fire rate would be reason to have them banned from multi-residential and business buildings.

Fire extinguishers, balls, bags, particulate, stickers, blankets, coatings, etc are all layers of fire response, but at the core of the issue is the cause of battery fires in the first place. How can they be prevented? Here are some ideas, please add any more you can think of.

• Using legitimate, high quality, tested battery cells
• Smart BMS to monitor the state of each battery cell
• Warning system that indicates when a battery cell may be close to a failure state.
• Battery packs that protect the cells from impact, vibration, puncture, and ingress
• Isolation of the battery packs from other sources of heat (control boards, motor cables)

Hopefully manufacturers will implement some of these ideas, but I suspect they will only do so after enough outcry from the community.

[RagingGrandpa]

Sure... but...

NMC cylinder cells can runaway, and the only way to change that fact is to change to a different cell type.

Unfortunately, NMC cylinder cells are the only high-power-density affordable option today. I can't fault EV and PMD manufacturers for using them- I would hate to own an EUC full of LFP cells that gets 40% less range for the same size and weight.

To your five points- I would argue that 1, 2, 3, 4, 5 are already achieved with today's EUC's. I support asking for improvement in #3 (e.g. a more clear warning than just interrupting charging)... but I still think we'll need to accept a 10ppm incidence of cell fires, as long as we use NMC

I accept this risk.

Edited January 29, 2021 by RagingGrandpa

[Chriull]

4 minutes ago, RagingGrandpa said:

To your five points- I would argue that 1, 2, 3, 4, 5 are already achieved with today's EUC's. I support asking for improvement in #3 (e.g. a more clear warning than only interrupting charging)...

For number 2 a cell undervoltage warning is missing. As the undervoltage protection by cut off after the first generation EUCs was removed to save us from faceplants nothibg was implemented to replace this.

Imho a big point regarding safety.

For Number 3 temperature monitoring could be some nice addition.

And BMS without any overcurrent/short circuit protection are about grossly negligent anyhow...

Number 5 could be an important point, too. But that's just gut feeling as we don't get any forensic details here ...

[Asphalt]

14 minutes ago, StealthPhoenix said:

@Asphaltif i had used such a product, idve provided the link already.

there is only one product currently that im entertaining https://www.hot-stopl.com/product-details.html

Yeah, the problem is that there isn't an inexpensive, convenient, fool-proof solution currently. So the next best thing is to have multiple layers of mitigation and response.

IMHO, fire stickers can be one of those layers. I'm definitely not relying solely on fire stickers to put out a battery fire!

 

24 minutes ago, StealthPhoenix said:

with the stickers suggested, have you tested them under duress? they seem awfully small to stop any fire from the battery packs. but i WOULD consider buying a whole bunch and just lining the whole inside shell with them, or around the entire battery pack...not just one strip.

i dont know, you are the experienced one here. tell us.

I have not tested them under duress. I'm guilty of being convinced by YouTube videos, reading some online information, and messaging the owner of the company with some questions.

The stickers do seem small, but if you trust the specs a 100mm x 50mm sticker is supposed to be able to suppress a fire in a 20L volume. Like you, I decided that more stickers would be better, so I went with two stickers for one wheel. I may add more later, but I should state that my expectation is not that these fire stickers will completely put out the fire; my expectation is that the fire sticker will reduce the temperature enough to buy me enough time to get the wheel to a safer location. Stopping thermal runaway would be a nice bonus.

[Asphalt]

20 minutes ago, RagingGrandpa said:

To your five points- I would argue that 1, 2, 3, 4, 5 are already achieved with today's EUC's.

I would say that the five points CAN be achieved today, but manufacturers are currently not implementing all of them in any wheel. The closest might be the Ninebot Z10 and InMotion wheels, but I don't know any manufacturer that monitors individual cells.

Current Gotway wheels might score 2/5 if their assembly line is having a good day 

 

27 minutes ago, RagingGrandpa said:

I accept this risk.

I accept this risk as well.

My worry is that governments won't, after a few fires make the headlines.

[RagingGrandpa]

• Using legitimate, high quality, tested battery cells
  They're using new, pristine, name-brand cells. Perhaps more culling or matching during pack assembly could be done, but it's unlikely to get us below 10ppm.
   
• Smart BMS to monitor the state of each battery cell
  Our BMS does monitor each cell for OV and UV... just it can't do anything about it except during charging. But this is not nothing- cells that go bad slowly do get detected!
   
• Warning system that indicates when a battery cell may be close to a failure state.
  That's charging interruption. More clear notification would help; but we're not starting from zero here.
   
• Battery packs that protect the cells from impact, vibration, puncture, and ingress
  Cells are mounted in frames (vibration), installed in a foam-lined rigid-plastic enclosure (impact, puncture), and crudely sealed (ingress). What more can you practically expect in the very tight space provided?
   
• Isolation of the battery packs from other sources of heat (control boards, motor cables)
  There are plastic walls, and often foam, and never metal conduction, between the power electronics and the pack. More 'firewalling' between the controller and pack could be helpful, but again we're not starting from zero.

.02

[conecones]

Just want to help ease some worries and point out the difference between lithium ion batteries, which are the common lithium rechargeable batteries in EUC's, laptops..etc and the lithium metal batteries which are the common lithium non-rechargeable batteries (Energizer lithium AA and such). Lithium ion batteries are actually fairly safe given how widely used they are. Rechargeable lithium metal batteries do exist and have huge potential but are still being developed and not safe at the moment.

Lithium Ion battery after being smashed open with a hammer and dropped into water:
https://www.youtube.com/watch?v=RWxzDTK6lwM

V.S.

Lithium Metal battery peeled apart and dropped in water:
https://www.youtube.com/watch?v=cTJh_bzI0QQ

So don't freak out if you google "lithium battery in water" since EUC batteries aren't those.

It looks like from the videos, board fires are the common culprit and if this spreads to the batteries its game over. So IMO, just a proper BMS to monitor bad cells and isolating the motherboard to prevent fires/sparks from spreading to the battery pack is the easiest, most reliable solution and probably all we can hope for in the short term since its a cheap fix. Cases where the board fire doesn't ignite the battery aren't so bad and the wheel is totally repairable afterwards. I just don't think we can ever completely prevent boards from shorting given the 84v/100v running through there and connectors aren't going to be totally waterproof.

For my Gotway I'm just going to goop the crap out of the areas on/around the motherboard where the high current wiring terminates and cover the space around batteries with fireproof sealant since I have tons of left overs from work. Can be removed if needed like the white sealant Gotway uses.
https://www.hilti.ca/c/CLS_FIRESTOP_PROTECTION_7131/CLS_FIRESTOP_SEALANTS_SPRAYS_7131/r3859360

I think these stickers would be fantastic to put out the board fires, so would make sense to put them near the boards rather than at the batteries. If the batteries catch fire, even a full size fire extinguisher would have difficulty so these stickers won't help there.

The guy who had his MSP blow up while not charging or being used recently is a mystery though. Seems like a defective battery/internal shorting issue (not related to Gotway's QC as they outsource these) and would be really interesting to know if anyone has any theories on how this happened. 

[314ka4y]

Hi Guys,

Sorry, I missed the link to the forum 
For Ideas mentioned before:

- Using legitimate, high quality, tested battery cells
Nope. In South Korea, they had a lot of cases with Samsung cells. Good cells won't be safe either( probably it is a good idea not to install the shitty ones, but you can't control manufacturers. 

- Smart BMS to monitor the state of each battery cell
They should have BMS all the time. Control of battery state is significant for li batteries, and they do have them. But it doesn't save.

- A warning system that indicates when a battery cell may be close to a failure state.
BMS functions don't help. 

- Battery packs that protect the cells from impact, vibration, puncture, and ingress
It is a good idea, but it is not so easy to do. And for many EV manufacturers to difficult to do because RD costs too high when everything works/sells without it.

- Isolation of the battery packs from other sources of heat (control boards, motor cables)
Heat is not a problem for packs. It is ok if the battery pack in a 40-50 degrees environment. And from the other side, it isn't easy to do in the mono-wheel. 

From the theoretical part :

- LFP batteries are more stable, and they caught fire very rarely. But I haven't seen them on personal devices

- As somebody mentioned before: several layers of protection for safety.

From the practical part:

Is there anybody from distributors/resellers/enthusiasts in North America who are willing to sacrifice several packs of old Li batteries?

I think it is a good idea to do several tests with over-voltage and see stickers' performance?

I think it can be done just in the usual metallic/plastic box, with tight packing and over-discharging cells. We can provide free stickers for this endeavor.   

 

[314ka4y]

To clarify all obvious observations, like a sticker is so small, it won't work to extinguish.  

Sticker is a flooded fire suppression system that works in the enclosure. So the fire extinguishing starts when agent concentration reaches a value around 7-8%. 

Just an example of how they calculate the required amount of fire extinguishing component to big rooms with the same fire extinguishing components:
coursehero.com/file/23273269/FM200-Calculator/

From the example: 375 m3 - 212 kg required. If we continue our proportion: 30L (0.03m3) - around 15 grams of fire extinguishing components.
Moreover 
- the sticker is near the heat source, so concentration is achieved faster and more proportional. 
- Actual amount of space in a tight enclosure is around several liters
- Sticker can't extinguish lithium fire, it reduces the temperature of the other cells, so other cells won't catch fire from the starting one. Extinguish lithium fire is a very tricky mission. The fire will go away on its own, and the major task is not to allow thermal runaway of nearby cells

[WI_Hedgehog]

It appears the cooling strips (stickers) might be best used as a two full sheets the same width & length as the battery pack, placed on each side of the welded battery pack, directly against the cells, and held in place by the PVC shrink wrap (blue plastic) placed over the cooling material. If a cell were to go critical the sheet would cool the cell and all cells immediately surrounding it in a similar manner as shown in the demonstration video. This cooling effect may stop the chemical reaction in the critical cell, though more importantly should stop surrounding cells from heating to the point of going critical, therefore preventing a chain reaction. 

Given the nature of lithium cell fires it appears in my humble estimation that anything less will not be effective.

[Skeptikos]

On 4/14/2021 at 4:56 PM, 314ka4y said:

To clarify all obvious observations, like a sticker is so small, it won't work to extinguish.  

Sticker is a flooded fire suppression system that works in the enclosure. So the fire extinguishing starts when agent concentration reaches a value around 7-8%. 

Just an example of how they calculate the required amount of fire extinguishing component to big rooms with the same fire extinguishing components:
coursehero.com/file/23273269/FM200-Calculator/

From the example: 375 m3 - 212 kg required. If we continue our proportion: 30L (0.03m3) - around 15 grams of fire extinguishing components.
Moreover 
- the sticker is near the heat source, so concentration is achieved faster and more proportional. 
- Actual amount of space in a tight enclosure is around several liters
- Sticker can't extinguish lithium fire, it reduces the temperature of the other cells, so other cells won't catch fire from the starting one. Extinguish lithium fire is a very tricky mission. The fire will go away on its own, and the major task is not to allow thermal runaway of nearby cells

You have an awesome product here, if it works.

You mentioned it stops 100Ah battery fires. From what I understand, EUCs often use 18650 batteries with thousands of Ah. That's a big difference. [Edit: I was looking at mAh instead of Ah, nevermind.] We've seen that traditional ABC fire extinguishers struggle to stop these fires, and it sounds like the fire stickers are made out of similar stuff, so it's not obvious they'll work here. Needs testing. I'm surprised your company isn't already testing this, given that there are so many potential buyers.

 

I read about these F-500 EA fire extinguishers. Unlike most ABC fire extinguishers, they're effective against lithium-ion fires. Apparently it works kind of like soap when mixed with water, making it easier for the water to seep into batteries and "encapsulate" the combustible material inside. This seems like the most practical way to defend against PEV fires, at least on the consumer side. I'm surprised I haven't seen anyone bring it up before. Though I could only find it on sale to consumers in Australia (here). Otherwise it's harder to get.

But still, there's been a lithium-ion fire extinguisher the whole time and no one said anything? I'm a little confused about that.

Spoiler

Edited March 30, 2022 by Skeptikos

[Menace]

7 minutes ago, Skeptikos said:

From what I understand, EUCs often use 18650 batteries with thousands of Ah

All are well under 100Ah. Each one of gotways 900wh packs is 10Ah, so the biggest eucs (monster pro/sherman max/commander) have only 40Ah. If it is Wh you mean then you are correct.

[Skeptikos]

22 minutes ago, Menace said:

All are well under 100Ah. Each one of gotways 900wh packs is 10Ah, so the biggest eucs (monster pro/sherman max/commander) have only 40Ah. If it is Wh you mean then you are correct.

Oh you know what, there was an "m" before the Ah on the page I was reading. I totally missed that. So nevermind, I take it back

[quickbot]

On 1/27/2021 at 3:29 AM, Asphalt said:

That CellblockEX looks like a good active response to a battery fire if you're at home and can deploy the particulate over your EUC.

What I like about the stickers is that they are a passive system and will deploy even if you're not at home - even if there's a fire while you're riding!

I wouldn't trust any single fire suppression product. We should all probably be using multiple fire response options.

A video talking about a fire response system would be interesting to a lot of PEV and drone enthusiasts:

• Fire alarm
• Fire extinguisher
• Fire blanket
• Fire balls
• Fire box
• Fire particulate
• Fire stickers
• Escape route

Dont forget a proper fullface respirator.

[Skeptikos]

On 3/30/2022 at 12:18 AM, Skeptikos said:

I read about these F-500 EA fire extinguishers. Unlike most ABC fire extinguishers, they're effective against lithium-ion fires. Apparently it works kind of like soap when mixed with water, making it easier for the water to seep into batteries and "encapsulate" the combustible material inside. This seems like the most practical way to defend against PEV fires, at least on the consumer side. I'm surprised I haven't seen anyone bring it up before. Though I could only find it on sale to consumers in Australia (here). Otherwise it's harder to get.

But still, there's been a lithium-ion fire extinguisher the whole time and no one said anything? I'm a little confused about that.

I emailed Hazard Control Technologies to ask why these aren't sold to consumers in the US. According to one of their manager/technicians, it's because UL doesn't have a certification for lithium ion fire extinguishers. (UL is a big deal in fire safety.)

But you can email info@hct-world.com to get one. They sent me a quote for a 2.5 gallon extinguisher, it's $216 for the extinguisher and $16 for the recharge pack (you have to set it up yourself). That Australian site says "The 9L [approximately 2.5 gallons] Lithium-Ion Fire Extinguisher has been tested on a 4.8KWh Lithium-Ion battery fire", so it should be good for EUCs.

This is the only thing I've seen so far that will actually stop a battery fire after it's started. Haven't decided if I'll get one yet, but if I get something for fires it will probably be this.

[Paul g]

On 9/8/2022 at 1:08 PM, PourUC said:

That's not the ONLY method of filling the chamber with gas. It's just an example, that very brand sells larger versions of that product or you could get a canister system.

Removing fire means less heat which means batteries combust over a longer period of time meaning less peaks in heat generated and less risk.

Not to mention, if you stop a battery fire initially you may well prevent other cells going into thermal runaway and not just delay them. For example, on EUC's batteries are on both sides of a wheel. If you prevent a fire for long enough you may stop the other side going into runaway.
 

Wow, if that thing works in reality as in this demonstration, that it is something!

[Paul g]

“Firesticker” is not a good name. I put “firesticker” on google to see if I can buy it in UK, and all it shows are stickers with fire signs on them.