Newbie question, what is battery venting?

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Thrasher

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If the battery shorts or becomes damaged the battery can vent. This means the chemicals inside the battery have gone into melt down. When this happens they sometimes create gas

The metal case of the battery has a hole, or safety vent on it. Once the pressure inside is too high the vent pops and let's the gas out.
This is called venting. And it is a safety feature. If there is no way for the gas to come out the cell could explode from pressure..
 

Baditude

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batteries vent during normal usage, charge and discharge. It's usually minimal. The warmer they get the more they vent, which is why for example your battery will last longer charging at .5 amp as opposed to 1 amp. It doesn't build up as much heat.
Uhmmmm. Just no. o_O
 

Baditude

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So it's not a chemical reaction. In which case your battery will last indefinately.
Venting is not a normal occurance, it is the result of battery failure caused by a hard short or over-discharge. The battery over-heats, and goes into irreversible thermal runaway. The heat build-up inside the cell produces hot gas, and is allowed to "vent" out the end of battery (as designed). The problem for us who use a mechanical mod is it must have vent holes to allow the hot gas to escape from the mod. If it doesn't, the pressure builds up and the mod becomes a pipe bomb.

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What you are describing is normal aging of a battery. The chemicals eventually become unable to allow a battery to adequately hold a charge. This has nothing to do with venting.
 
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noway

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What you are describing is normal aging of a battery. The chemicals eventually become unable to allow a battery to adequately hold a charge. This has nothing to do with venting.

Oh so venting to you is a battery overload. Look into what happens to those chemicals and why they no longer allow a charge to hold.
 

Baditude

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Thrasher

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Batteries vent during normal usage, charge and discharge. It's usually minimal. The warmer they get the more they vent, which is why for example your battery will last longer charging at .5 amp as opposed to 1 amp. It doesn't build up as much heat.
This was more common with ni- mh and other rechargables. The li battery we use is sealed, moisture and lithium do not mix and can't be exposed to air like that
 
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nyiddle

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Battery venting (or "thermal runaway") is when a battery discharges all of its nominal voltage violently, and in a VERY short period of time (we're talkin' like half a second or less) -- you'd have barely any time to react.

The result is that the mod will be pressurized almost instantly, and could potentially have a "pipebomb" effect if the gases can't escape properly.

Even if the mod has "vent holes" they'd need to be pretty massive to properly get rid of the HUGE/rapid pressure buildup. Most mods with vent holes in the bottom are strictly aesthetic (and so they can claim "this mod has safety features"). I promise that, in a case of thermal runaway/a hard short, some dinky little 5mm holes aren't going to get rid of the gases fast enough to prevent the mod from expanding/potentially exploding.

How to avoid battery venting?

Know your battery's limits. Know the warning signs. If your battery is hot, even WARM, stop what you're doing and re-assess the situation. Do you have a short? Coil touching the posts? Did you check the ohms? Are the ohms within the safe range of your battery's amperage? Are the ohms fluctuating?

It's normal for a mod to get hot as a result of hand warmth/the atomizer transferring heat, but it is not normal, under ANY circumstance, for your battery to be warm.
 

Baditude

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Even if the mod has "vent holes" they'd need to be pretty massive to properly get rid of the HUGE/rapid pressure buildup. Most mods with vent holes in the bottom are strictly aesthetic (and so they can claim "this mod has safety features"). I promise that, in a case of thermal runaway/a hard short, some dinky little 5mm holes aren't going to get rid of the gases fast enough to prevent the mod from expanding/potentially exploding.
Here's an example of an AW IMR battery which vented in a bookbag, probably after coming into contact with something metallic like coins or keys. The "guts" of the battery have mushroomed from the outer cell. I admit, this is an out-of-the-ordinary & dramatic example, but imagine this happening in a mechanical mod with tiny vent holes.

phot1o-jpg.255217
 
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Mooch

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    Here's an example of an AW IMR battery which vented in a bookbag, probably after coming into contact with something metallic like coins or keys. The "guts" of the battery have mushroomed from the outer cell. Imagine this happening in a mechanical mod with tiny vent holes.

    Ouch!
    A perfect example of "jellyrolling", another term that folks might see used for a cell that bursts. Though I see it more often with LiFePO4 cells than with the other chemistries.
     
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    Mooch

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    How often does it need to be if it's your battery that vents?

    Not sure I understand your post (definitely some sleep deprivation going on here), but....
    Absolutely never, I would hope for every person using a battery powered device (vaping or otherwise)!

    I was only referring to my destructive cell testing experiences (for clients). The other Li chemistries have typically just popped open a bit or only vented gas. The LFP cells have jellyrolled more often than the other chemistries when venting has occurred. They have definitely not vented more than other chemistries though, quite the opposite by far. As expected.
     
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