Jump to content

MSP & garage fire!


Recommended Posts

  • Replies 77
  • Created
  • Last Reply

Top Posters In This Topic

Top Posters In This Topic

Popular Posts

Well, I had one of the worst imaginable events happen with my wheel other than injury, which I've already conquered many times in the past.    5 days ago...my MSP C30 wouldn't charge after a 10 m

I'm going to go out on a limb and say "stressing" the bad battery pack led to the ultimate failure. Even an idling wheel on a bad battery pack is probably not good. Nothing like hindsight though.

Stressing a pack with a bad cell by charging or discharging should not be done in any case! Never ever!  From the reports here there seem to be three stages of battery degradation - the firs

Posted Images

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

 

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

Edited by AtlasP
Link to post
Share on other sites
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..

Link to post
Share on other sites
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!

Link to post
Share on other sites
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.

Link to post
Share on other sites
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?!? :blink:

Link to post
Share on other sites
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?

Link to post
Share on other sites
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).

Link to post
Share on other sites
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.

Link to post
Share on other sites
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. 

Link to post
Share on other sites
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. 

Link to post
Share on other sites
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 by Planemo
Link to post
Share on other sites
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 :cry2:

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. :blink1:

Edited by winterwheel
Link to post
Share on other sites
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 by Chriull
Link to post
Share on other sites
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.

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...