How feasible is a battery enclosure that is vacuum sealed, containing no air and therefore no oxygen?
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The way it works makes it dependent on how it gets applied. It forms a shell around the battery. If it was in an enclosure already surrounding the battery it would require far less than it would take if pouring a bag on something. Anyway, that’s why I want to test it. We’ll see what happens.
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It is very difficult to maintain a hermetic seal on things that are not as flexible as a skateboard. With all the wire and button penetrations it would be next to impossible. The argon probably has more promise by flooding the enclosure. I am wondering if it is possible to get it in little cartridges like CO2 or N2O.
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Isn’t Tesla using any fire suppression system?
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Just cast the battery in a solid block of low density epoxy, not only would it keep all air out, it would keep moisture away and prevent anything from rubbing or bending to much…only cost is the pack is permanent
The pack wouldn’t flex any more. The heat rejection and thermal stresses on the battery would be very bad.
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Here are some firefighters putting out a Tesla fire. If they use a suppression system it isn’t a very good one. There is a hint in the article though. Break the circuit first before you try to put out the fire.
https://jalopnik.com/watch-volunteer-firefighters-in-austria-extinguish-a-fi-1819665352
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Isn’t there a thermally conductive urethane rubber now?
I was thinking about @RipTideSports’s urethane. It has a better shot at working.
I was thinking blow air into it to reduce the density. Blow argon into it to reduce the density.
My guess is they just rely on paranoid settings in BMS and reporting to make sure failures get caught and corrected. Definitely been a few incidents in the past with the S7 and before that I was doing IT when Dell had an issue with cells I think from panosonic that were exploding in laptops so definitely possible for bad ones to get into the production line but my guess is since Tesla does more vertical integration they can probably QC and trace things if there are issues a little easier than between different companies (still outsource a lot of their cells though I think).
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We have these small disposable cylinders in the EU, considered a waste of time in the welding scene due to running out during or shortly after a piecework, but maybe good in this application
I think all you can do is try to reduce or mitigate collateral damage, you will have a hell of a time limiting the damage to just the board. For a Tesla reference and the death of a Florida driver
"The Tesla’s battery reignited twice on Monday morning at a salvage yard where it was towed, Davie Fire Marshal Robert Taylor said.
Tesla said in a statement that it posts language on its website for first responders saying that fires can take up to 24 hours to extinguish and that they should consider letting the battery burn while protecting exposures to buildings."
COLLATERAL DAMAGE CONTROL is all you can hope for.
That was the original thought. I’m worried about setting off the next California wildfire
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All you can do is drag it away from fuel sources and throw dirt on it
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It’s a chemical fire apparently and removal of oxygen will not stop combustion, maybe it would affect the intensity and ability to create flames dunno
Interesting
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It will extinguish if you can get the reaction rate down low enough for it to stop auto-oxidizing…maybe a tank of liquid N2? A frozen battery should be ‘safe’
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Little.bit of research revealed AVD fire extinguishers. Obtainable in various sizes.
Video shows it working. The cell is small but it goes out quickly so I imagine if you get the extinguisher on it fast enough you’d be ok.
If you had a inlet to your enclosure, and could fill the enclosure with this in case of a fire, I guess it would do a very good job of keeping it from getting out of hand.
Somewhat in depth article:
https://batteryuniversity.com/learn/article/safety_concerns_with_li_ion
AVD:
https://www.avdfire.com/how-does-avd-work
Though I can’t seem to find them for sale?!
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Class D extinguisher?
The company that picked up a deal with 60 fed ex planes uses foam
Argon is actually the gas of choice as it is completely inert, it is one of the components of ‘cargo foam’ which is the existing solution for lithium fires
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