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ManhattanRailfan t1_jb6xer1 wrote

Reply to comment by upL8N8 in Exploding e-scooter battery sets off massive fire, 'extraordinary damage' in Bronx supermarket by OntheRunfromCIA

How about regulating the sale of batteries rather than making an affordable, efficient, and societally beneficial means of transportation more difficult?

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upL8N8 t1_jb70o6i wrote

Legislation was just passed a few days ago that regulates battery sales in NYC, but that only applies to stores in the city AFAIK. There will still be people ordering batteries online or bringing them in from outside the city.

Registration / certification of the PEVs kills two birds with one stone. It ensures the battery packs / controllers being utilized are safe, and it tags the personal vehicle with a number that can be tracked if it breaks the law, making the owner liable.

Battery cells aren't the only cause of fires. There could be issues with motherboards/controllers starting on fire, motherboard / charger safeguards failing and causing a power surge to the battery. (each pack should have a fuse to protect against this.

IMO, all packs should have smart BMS built in with proper warnings for when cells aren't charging / balancing properly, or proper warnings for a thermal event. It'll cost more, but the more produced, the more they take advantage of economies of scale.

Even with all of these safeguards, battery cells can still fail and short out... for example if a dendrite pierces the cell separator and shorts out the cell or if the PEV was in an accident and there's no visually apparent damage. Until we have cells that are simply incapable of combusting, PEV batteries probably should be stored in a secure location, IMO. An apartment could build a safe storage locker, or maybe they only allow batteries of a certain size with the tenant proving they have a certified battery box / bag in the apartment that they're required to store their battery or PEV inside of that'll help to smother flames in the even of a fire. Probably wont' do anything about smoke though...

Something like this for small batteries:

https://firesak.com/

I personally own an EUC with a relatively small battery (1 kWH) as far as EUCs go, but I live in a house. A firesak would likely work for me, but I'm planning to build a battery box for it soon and in the event I buy a larger EUC in the future. Some EUCs have batteries as large as 3-4.5 kWh. Upwards of 40 lbs of cells packed tightly next to one another. You can't simply remove those packs, and there's no good way to safely contain those units inside an apartment. IMO, those units shouldn't be allowed in an apartment, no matter how well done the electronics are and battery packs were constructed. If a single goes into thermal runaway and that runaway spreads, it could create one helluva fire.

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ManhattanRailfan t1_jb71h6j wrote

By your logic you should need a license to have a phone or computer and store them in fireproof cases as well.

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upL8N8 t1_jb7klax wrote

Actualy, I didn't say anything about a license. I said one should have a registration and certification for their device.

Comparing a cell phone with a 10-20 Wh battery capacity and low fire potential, or a laptop with 50 - 150 Wh battery capacity and relatively low fire potential to PEVs with anywhere from 250 to 5000 Wh is a bit of an apples to oranges comparison. Not to mention that many PEVs aren't certified in any way, versus cell phones / laptops that often are.

Cell phones / laptops can definitely start on fire, but when they do, it's far more tame and more manageable to deal with. The smoke is toxic, the fire is hot, but the overall battery size is small enough where it can be handled.

Some examples:

https://youtu.be/O4AoI6W_F4Y?t=211

It's why batteries up to 100 Wh are allowed on planes. They're a bit PITA if they start on fire, but they likely won't kill anyone.

That isn't the case with a battery that's 10x-500x the capacity of a cell phone battery, or 2x-33x the size of a laptop battery.

If small e-bike batteries don't pose a serious threat, then maybe they don't need certification. However, given that a lot of people are buying PEVs with MUCH larger batteries, it becomes critical to ensure those battery cells, battery packs, monitoring systems, cooling systems, charging systems, and controllers are designed properly with low risk of fire.

Here's what a PEV fire with 2200 Wh battery looks like:

https://youtu.be/8h41p13e4TU?t=610

You gonna be the one to pick that up in the middle of your apartment or next to the door of your apartment and throw it in the tub? You gonna try to run past it? Pour some water on it? Think a fire extinguisher is gonna stop it? What they don't mention in this video is just how HOT lithium ion cells burn, making it easier to start things around it on fire. Making it harder to approach.

You'll note that the above fire wasn't caused by a failure in the cells; it was caused by a failure in the motherboard.

Here's the video of the PEV starting the grocery store on fire yesterday:

https://www.youtube.com/watch?v=MY2JTlC_3Eg

Here's one with only a 650 Wh battery:

https://www.dropbox.com/s/mykajobdy7m9lh2/20180916_052136.mp4?dl=0

Here's one with a 3100 Wh battery... in a firesak. (Firesaks are only tested with batteries up to 2000 Wh)

https://youtu.be/WFLHCIbDJAw?t=943

(I'm posting EUCs because those are my PEVs of choice and I'd seen the videos already)

Actually, that last two remind me of an issue not often brought up. Laptops and cell phones are either often sealed against water ingress, or they're often tucked away from water. PEVs OTOH may not be certified against water, yet a lot of people ride them in the rain.

The 650 Wh case I believe he said he rode in the rain before experiencing electrical issues; this was an early model that they've since re-designed. In the 3100 Wh case... the guy accidentally dropped the EUC in water; says he dropped it in a pond. He thought it was fine because he took it apart, dried it out, and it was still operating properly; you can see him riding it just before the fire. Luckily he was smart enough to know that there was the potential for bad things to happen while charging, so they took it out to the middle of nowhere to charge it up. Imagine you live in an apartment with a neighbor living below you who isn't so smart.

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