Where is the danger of a battery explosion?

[Winblows]

ohm = Volt\Amp
Volt=Amp*ohm
Amp = Volt\ohm
Watt = Volt*Amp

I've been counting this Ohm's law over and over again and I wonder, what situation makes a battery getting dangerous?
Which results of the calculation gets the battery stressed, or in human language, "may explode".

A battery is sitting in a mech mod at 4.2V with a coil in a tank tank measuring 0.25ohm.
That gives

4.2/0.25=16.8
4.2*16.8=70.56
16.8Amps and 70.56Watts

OK, no rocket science here.

Since the situation is running at a mech mod, the battery will run until I decide to replace it with a new one (recently charged).

So we lose voltage and reach 1.5V
1.5/0.25=6
1.5*6=9
6Amps and 9Watts

We lose even more voltage and reach 0.5V
0.5/0.25=2
0.5*2=1
2Amps and 1Watt

Let's run the same calculations on a frankencoil build at 0.05ohm!
4.2/0.05=84
0.05*84=4.2
84Amps and 4.2Watts

1.5/0.05=30
0.05*30=1.5
30Amps and 1.5Watts

0.5/0.05=10
0.05*10=0.5
10Amps and 0.5Watts

So, can anyone tell me an example of dangerous situation? because I've seen and read a lot about "not stressing a battery in a mech mod", but I just can not find a combo of digits put into the Ohm's law that makes me feel scared?
Is the situation with the frankencoil at 0.05ohm pulling the 84Watts "stressing the battery"?

Let's get some real examples put in the theory here.

Thanks!

 

[Ben85]

You aren't pulling 84 watts, you are drawing 84 amps from a cell that cannot do that safely (in a single tube mod).

 

[Winblows]

@Ben85: ups, sorry, typo error

 

[bussdriver]

If you run your batteries down to such low voltage levels you are discharging them down to an UNSAFE level. Buy a regulated mod.

 

[Winblows]

If you run your batteries down to such low voltage levels you are discharging them down to an UNSAFE level. Buy a regulated mod.

Yes, and here comes 2 unanswered questions.
1. What is "such low voltage"?
2. What is "UNSAFE level"?
A regulated mod? I already have 5

 

[bussdriver]

A good thing for all vapers of mechs to do is read through these forums for Mooch's info on batteries. Info regarding safe discharge currents can be found there. 84 amps is way too much! Discharging below about 2.5 volts ruins the battery, and makes it unsafe to recharge!

Don't be a troll! Do your homework! Use your regulated mod!

 

[Winblows]

Thanks, dear @bussdriver.
That explains a lot.
Regarding the "read through these forums for Mooch's", I was hoping that I could create a thread that could "put it all together".
I certainly use the regulated mods and controlled batteries at home and/or when I have my bag/backpack with me.
When I go to work or just "go out", I put a fully charged battery in one of my mech mods and use it until I get home and then put the battery into a regulated mod until it's safety discharged.

The reason why I use the mech mods is the matter of personal vanity and the ease of having them with me.

 

[Topwater Elvis]

'Over stressing' a battery is more of a general term for abusing.
Many situations are considered abuse, any use that causes the cell to heat beyond warm, exceeding the CDR isn't a safe practice, over charging or discharging, accidental button presses, to name a few.
There are literally dozens of scenarios that could cause a cell inside a mechanical to become unstable.

Having a cell explode is fairly rare, usually a cell vents to release internal pressure. If a cell vents pressure while contained in a tube that doesn't have an adequate way to release this pressure or the tube ventilation is blocked due to the cell bulging/swelling the tube can swell bulge split rupture or explode.

Relying on any cells ability to vent hot pressurized gasses to prevent rupture or explosion is foolish as is relying on any tube / mech to have adequate ventilation to prevent pressure build up.

There are dozens of threads 'that put it all together' ,,,
they all start with basic battery safety 101.
Something every mechanical user should already know before pressing the fire button for the very first time.

When using a mechanical there are no short cuts or an easy button when it comes to using one safely.
The only single safety feature is the users knowledge & close attention.

Something with no safety features is probably a poor choice for going out & about, regulated power devices have built in safety features, mechanical's have none.

 

[Winblows]

What are the possible symptoms of 'over stressing'? I mean, will the mod get hot, indicating that something is not as it should be or will the battery just suddenly explode?

 

[Ben85]

You need to go and read mooch's blog. All of the answers to your questions are there.

 

[Topwater Elvis]

Again, over stressing = abusing.
Don't abuse your cells & you should have no problems.

Was my first response confusing or poorly worded?

Not trying to be rude or seem harsh;
From your concerns & questions it sounds like it would be best not to use a mechanical at all until you understand basic battery saftey, your gear & what you're doing & why.
Then basic mechanical saftey, proper battery selection, how to dissemble fire button, clean it, reassemble correctly, how to clean threads, know the difference between 510, hybrid, direct to battery contact (false/fake hybrid) ect..

Accurately measure the resistance & check for shorts before pressing the fire button. This requires use of a multi meter or something similar to a 521tab and the knowledge to use one correctly.
Never exceed the CDR of any cell, best to always leave a saftey margin under the CDR just in case.
Some folks use 10% under, some 50% under the CDR.

All the very basic stuff you should know before pressing the fire button on a mech for the very first time.

How do you know if its going to cause a battery to vent or cause an unsafe condition or even a possible catastrophic failure?

Know enough about what you're doing before you do it so you don't create an unsafe condition to begin with.

 

[Hawise]

What are the possible symptoms of 'over stressing'? I mean, will the mod get hot, indicating that something is not as it should be or will the battery just suddenly explode?

There may not be any. The battery getting hot is definitely a sign your battery is overstressed, but if it's in the mod and not heating up too much you may not notice it. So you go along vaping away, and your battery gets stressed (a.k.a. damaged) and warms up a bit each cycle. But it works just fine. Again and again. Until the damage is too much for it. Then what happens? If you're lucky, it doesn't work. You try to pull more amps than it can provide, the voltage collapses and nothing happens. If you're not lucky, it goes boom - on exactly the same coil and settings you've been using all along.

Start with the CDR. And to know that, you'll need a reliable battery - see Mooch.

Now you've done your homework and have your 20 - 30 A battery. Next step is to calculate your load. Use Ohm's law for a mech and Mooch's regulated mod calculation for a regulated mod. Never ever use a setup where the load is higher than CDR. You can probably get away with it for a while - until you can't. Also, be careful of loads approaching the CDR. Batteries deteriorate with regular, safe usage, and also over time, without any usage. Do you know how long your battery was in storage before you bought it? It's best to stay well clear of the CDR, and even more so after you've had the battery a while.

You seem to be looking for indicators that will let you know for sure that you're doing something problematic before any harm occurs. There aren't any that you can rely on, which is why it's so terribly important to understand batteries, quality issues, Ohm's law and the rest. Some things will tell you you definitely do have a problem - overheating, physical damage etc. - but just because things are working well and there aren't any problem signs doesn't mean you're safe.

 

[Winblows]

As I read your knowledge, I can recognize all the aspects of electronics and the mechanics regarding mech mods that I know of and I appreciate your dealing with this thread.
Thanks!

I know that dealing with mech mods requires an extra attention and want to be up to date with the latest hints and possibly some new issues to be aware off.
Never the less, it's better with some extra attention to the security than ignorance.

What I am most concerned about are signs of the battery abuse whilst not having the right equipment (eg. a regulated mod) by the hand for checking the voltage.
All batteries that I use are quality products (Sony, Samsung, LG) checked with the Mooch list.
I usually carry 2 22mm mods and fully charged batteries that are put into the regulated mods for the rest of their voltage cyclus. I have not experienced that the batteries that I came home with were below 50% charged.

I'm a moderate vaper. My builds for the mech tubes are 0.25 - 0.5 ohm and I don't use hybrids

 

[Hawise]

What I am most concerned about are signs of the battery abuse whilst not having the right equipment (eg. a regulated mod) by the hand for checking the voltage.
All batteries that I use are quality products (Sony, Samsung, LG) checked with the Mooch list.
I usually carry 2 22mm mods and fully charged batteries that are put into the regulated mods for the rest of their voltage cyclus. I have not experienced that the batteries that I came home with were below 50% charged

And a good charger?

You've mentioned just using the mechs at the top of the battery charge cycle a few times. That does deal with the risk of overdischarging, but it's important to note that the load on a mech is highest when the battery is fully charged. It's the opposite with regulated mods - they pull the most current when they're nearly discharged.

 

[retired1]

My builds for the mech tubes are 0.25 - 0.5 ohm and I don't use hybrids

Depending on the battery, even .25 may be pushing it, especially if it's a 20A battery and not an actual 30A.

This thread is running extremely borderline on being moved to Not Advisable. Some of your battery practices are not what we'd recommend. Vaping by the seat of your pants when it comes to mechs and battery safety is a sure fire way of ending up on the 6 o'clock news some day.

 

[Winblows]

Thanks to all!
@retired1, you may close this thread.

 

[DaveP]

The more you stress a battery, including driving the battery down to low voltage and charge levels, the faster dendrites begin to grow. Be careful!


Roots of the Lithium Battery Problem: Berkeley Lab Researchers Find Dendrites Start Below the Surface | Berkeley Lab

The lithium-ion batteries that power our laptops, smartphones and electric vehicles could have significantly higher energy density if their graphite anodes were to be replaced by lithium metal anodes. Hampering this change, however, has been the so-called dendrite problem. Over the course of several battery charge/discharge cycles, particularly when the battery is cycled at a fast rate, microscopic fibers of lithium, called “dendrites,” sprout from the surface of the lithium electrode and spread like kudzu across the electrolyte until they reach the other electrode. An electrical current passing through these dendrites can short-circuit the battery, causing it to rapidly overheat and in some instances catch fire. Efforts to solve the problem by curtailing dendrite growth have met with limited success, perhaps because they’ve just been scratching the surface of the problem.

 

[Baditude]

As I read your knowledge, I can recognize all the aspects of electronics and the mechanics regarding mech mods that I know of and I appreciate your dealing with this thread.

I know that dealing with mech mods requires an extra attention and want to be up to date with the latest hints and possibly some new issues to be aware off.
Never the less, it's better with some extra attention to the security than ignorance.

A Beginner's Guide to Your First Mechanical Mod

• Covers the differences between a mechanical vs. regulated mod, essential safety accessories, optional safety accessories to add layers of safety to your mech, routine maintanance, use of proper batteries, proper ventilation, low resistance vaping, and faux hybrid mods.
  
  

Deeper Understanding of Mod Batteries Part 1

• For those who want to learn the differences between IMR, IMR/hybrid, ICR, and LiPo batteries. What do those numbers and letters on batteries mean? What's an amp rating and why is it more important than the mAh rating when choosing a battery for vaping?
  
  

Explain it to the Dumb Noob: Ohm's Law Calculations for a Mechanical Mod

• As simple as it is to use, some people have a tough time grasping the concept.

 

[Winblows]

Oh my Lord! This is a true introduction to the complicity of the world of vaping!
Thank you all!
I hope that this little bump to the subject will help not only me in this so important issue - dealing with batteries.

 

[DaveP]

Oh my Lord! This is a true introduction to the complicity of the world of vaping!
Thank you all!
I hope that this little bump to the subject will help not only me in this so important issue - dealing with batteries.

Mechs appeared on the market to provide a better vape than the early cig-a-like vape mods and the eGo models that came later. Those were limited to something like 3.4v and to get more vapor you had to go to a lower resistance coil. Mechs delivered a "straight wired" voltage to the coil and produced lots of vapor and flavor in the 3.7v to 4.2v range. Following them were regulated mods with fancy voltage synthesis circuitry that allowed voltage change by the user.

Then, adjustable wattage and TC mods began to appear, along with mods that could produce increasing wattage that finally topped out at 200 and 300 watts (supposedly). Some of those are advertised at imaginary and wishful numbers, but they sell like hotcakes.

So, mechs aren't nearly as safe as regulated mods and that's why everyone is urging you to make a change to a regulated mod. If you use a mech mod don't put it in your pocket between vapes. There's been a number of cases where shorting occurred and legs burned. It's hard to get one out of a pocket after it goes into runaway.



Keep reading the sub-topics under the current heading at the top of this page (link below) and there's a world of information here. Absorb and enjoy!

Vaping and the E-Cigarette | E-Cigarette Forum