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I just had the county inspector out to check the installation work on my Level 2 JuiceBox charger. His only question was if the Bolt requires venting when it is charging. As I can't fit a car inside my garage (the charger is inside and I run the cord out to the car and close the garage door over it) he had no problems, but the JuiceBox info said it needs to be used in an area where venting is not needed. The inspector said it is if chemicals get emitted from the car while charging it could spark an explosion or asphyxiate someone.

Being on the forums here for several months now, I've not heard of anyone saying you can't charge a Bolt inside a garage without ventilation.

Is the Bolt a closed system when charging?
 

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The main high voltage lithium ion battery is a closed system. Battery management system is supposed to prevent over charging/temp and short detection to prevent cell rupture and subsequent venting/fire. There might be small amounts of hydrogen released from the glass matt lead battery if its gone bad.
 

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XJ is right on this.

Lithium-ion batteries use charge controllers to precisely regulate the rate of charge and charging cutoff. They don't trickle charge, and as a result, don't form gasses.

Lead-acid batteries (normal car batteries) do not have much charge regulation, and are allowed to trickle charge even after they are fully charged. This can result in hydrogen forming and venting from the battery. Hydrogen is flammable, so any sparks or flame can ignite it. This is why instructions for jumper cables say to connect the red (positive) cable to the battery terminal first, and then connect the black (negative) cable to a metal surface away from the battery. This way if it sparks, it won't be near a potentially venting battery.

The disclaimer on the Juicebox is a result of covering their legal bases, not indicative of a likely problem. It would be a series of very improbable failures that would result in a spark causing a fire, and even more improbable that it would cause serious injury.
 

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Watch the youtube videos. Lithium-ion batteries are prone to fire when physically damaged.

They store a lot of chemical energy, so the results are spectacular when they release that energy all at once.

Then again, a ruptured fuel tank that catches fire is quite a release of energy too. I've seen quite a few gasoline cars completely engulfed in flames in my life, but so far haven't seen an EV up in flames.
 

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Watch the youtube videos. Lithium-ion batteries are prone to fire when physically damaged.

They store a lot of chemical energy, so the results are spectacular when they release that energy all at once.

Then again, a ruptured fuel tank that catches fire is quite a release of energy too. I've seen quite a few gasoline cars completely engulfed in flames in my life, but so far haven't seen an EV up in flames.
the electrolyte is flammable. when there's a thermal runaway, the electrolyte can vent and burst into flames. If other cells adjacent to the failed one start to runaway then you get a domino effect and you probably would have a fire similar to what you've seen with gasoline.

https://www.thesun.co.uk/motors/4721171/terrifying-tesla-video-shows-unstoppable-electric-car-inferno-that-took-35-firefighters-to-extinguish/
 

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From what I have read, over the last five years, EV fires are much less frequent than ICE fires, per vehicle, and per mile. Lithium batteries do require stringent control over manufacture, and charge/discharge. Automobile OEMs have done a better job at this than hobby/consumer device manufacturers. Not at all surprising, given the huge costs/liability involved.

Solid state lithium batteries could change all this. They could greatly reduce the need for thermal management, and the massive amount of computer hardware/software needed to protect lithium batteries.
 

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although, this is an interesting read. Notice GM battery lab explosion in #4 example.

http://nexceris.com/learning-from-4-damaging-lithium-ion-battery-failures/

I think peoples asumptions on this piece can be dangerous. This was a testing lab, a lab where they test their batteries, in all kinds of conditions to see what happens. We all know the dangers of lithium batteries. In this case it seems that when they off gassed in accumulated inside the chamber, this was most likely a test that they were performing like overcharging the battery or maybe even a test of code of battery management system, whatever. The takaway was they were not monitoring for gasses nor did the testing crew understand that this may have been a possibility.

Lastly the author makes a reference to the bolt and shows a stock picture of a bolt battery pack yet the event was april 2012! Hmm me thinks it was not a bolt battery, nor does the author specifically state it is or is not, but associates the even by the picture and opening paragraph
 
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