High Voltage, High ohm Mechanical Mod

[RtVaēpTek]

I fail to see the danger of using stacked 18350s in a mechanical mod as long as it is a high ohm coil. Say 8v and a 3.5 ohm coil is only 18w and pulling a little over 2A from the battery. As long as the batteries are matched voltage wise, there shouldnt be any problem, right? Ill wait for a response before I blow something up.

 

[patkin]

Don't stack batteries! Seriously, did you buy those from an ecig vendor? What do they say on their site? I don't mean to sound rude but this kind of thinking scares me. Do a search for a member here "Baditude" to learn what you need to know about batteries and safety. He has a blog all about it. I don't have time right now to find the link... someone will come along with more info.

 

[LDS714]

I dunno. I've had coils do funky stuff and drop the resistance to a near short.

That could be bad in the case you describe.

 

[RtVaēpTek]

How does this kind of thinking scare you? The idea proposed pulls less amps from the battery than the highest amp draw setting on a Vamo (1.2ohm/15w=3.54A). The only situation that I could think of that would be dangerous is if the coil shorted and I just kept pulling the firing button. Im searching for Baditute right now to read up.

 

[RtVaēpTek]

I read up on his blog, and the only danger that would pose is the idea of using stacked 18350s and a coil with a low enough resistance to to cause the amps to spike over the safe threshold. My batteries have a 6.4A max limit. I am utilizing 33% of the max amp draw from these batteries by stacking them using a high ohm coil. If I was asking if i could run a subohm setup while stacking in a mech mod I could understand the fear and stupidity that would be raised. I dont know, it was just a thought.

 

[John_]

How does this kind of thinking scare you? The idea proposed pulls less amps from the battery than the highest amp draw setting on a Vamo (1.2ohm/15w=3.54A). The only situation that I could think of that would be dangerous is if the coil shorted and I just kept pulling the firing button. Im searching for Baditute right now to read up.

In a perfect world, your coil is going to be perfect and not break. If your coil breaks and causes a short this is bad. Running a higher voltage through the same gauge of wire increase the chance you'll break it. If everything works perfectly, it's not dangerous at all. With stacked batteries you have a higher chance of something failing, simple as that.

EDIT: Honestly though it's not dangerous if you do it correctly. Batteries are stacked in all kinds of electronics, you just have to do it carefully and correctly.

 

[alkaiser]

if you use a lower gauge wire (like 28 or lower), you should be totally fine.

oops i meant lower

 

[hvfracingwilly]

I tottally agree with the original poster and do not see much of a threat if proper battery safety is followed. Hower I am confused as to why you would want to limit yourself to 800Mah capacity of the 18350 battery. Even at the lower draw from the cells the benifit is not there.

 

[Topacka]

As long as you understand the limitations of your batteries and don't push them too hard it's just as dangerous as any other build on a mech. Meaning watch for shorts, check ohms, all the other obvious things you probably do already.

 

[dripdaze]

Stacking batts. seems like a bad idea but I can see how it could be used to make a big cloud. Double voltage could make lots of watts. If you only do it one time???????

 

[Bosco]

I'm not a battery stacker but my understanding is that the primary concern in stacking batteries is that they will become unequally charged . .and one will start charging the other. That's why it's recommended to buy the batteries in pairs and always use them together . .ie . .so one doesn't age faster than the other.

I think as long as the batteries are in synch and you don't exceed their limits then you should be fine. At least I'd feel comfortable doing it if I had a reason to (currently, I don't). You can find some stuff about stacked batteries on this site (http://www.e-cigarette-forum.com/fo...scussion/355443-read-batteries-explained.html) and also the candlepower forum (Is stacking batteries safe as a single?).

 

[bones1274]

I stacked Tenergy 3.0v CR123A 750mah batteries in my REO Grand with a 3 ohm carto for 3 years before i switched to RBA's. Never had an issue. I have many friends that are still doing it with their REO's.

 

[dr g]

Stacking batteries has several failure additional failure modes over single cells, and requires additional battery management, so it is considered best avoided.

While perhaps not statistically that dangerous per se, most "exploding mod" stories involve stacked batteries.

 

[Funk Dracula]

I'm not a battery stacker but my understanding is that the primary concern in stacking batteries is that they will become unequally charged . .and one will start charging the other. That's why it's recommended to buy the batteries in pairs and always use them together . .ie . .so one doesn't age faster than the other.

I think as long as the batteries are in synch and you don't exceed their limits then you should be fine. At least I'd feel comfortable doing it if I had a reason to (currently, I don't). You can find some stuff about stacked batteries on this site (http://www.e-cigarette-forum.com/fo...scussion/355443-read-batteries-explained.html) and also the candlepower forum (Is stacking batteries safe as a single?).

This. ^^^^^^

1.) ALWAYS use and charge 18350 in pairs when being used in stacks. As batteries age, their internal resistance increases. You need these batteries to be performing as equally close as possible. Problems occur when one battery is working harder than the other. Some testing of batteries after coming off the charger, and after use should be in order. When you switch the batteries out, measure the voltage to make sure they are both draining equally. When coming off a charger, measure the voltage and make sure they are both charging to an equal level. Over time one battery may not be aging and performing as well as the other one is...

2.) The sky is not falling. Stacking batteries just requires more user caution and knowledge when attempting to do so. There is less room to screw up, and more room for a mistake; that is all. As with any mech, the only safety device in place is the USER.

3.) The hairy ....-crack avatar, join date, and thread topic guaranteed to start some sort of alarmist reaction and responses makes me wonder if the OP is just pushing buttons. Had to say it.

 

[RtVaēpTek]

Ive been vaping for a few years so I do have a well grounded understanding of vaporizers and their working systems. I also graduated from college with an electrical engineering degree, but I can see why my join date and avatar may raise some alarm. Using matched batteries I cycled through a set checking their voltage every few minutes as well as their temperature. The batteries 'died' with the same matched voltage. I'm going to stick with my single 18650 vct3 in my mod, but this was just sort of an experiment. It just seems like there is a ton of ''DONT STACK BATTERIES'' talk being thrown out there without any sort of real explanation as to why. Thanks for all the replys!

 

[Camwin]

The only reason everyone says don't stack is a more, "better safe then sorry" idealogy. Because sadly a lot of people who are newer to the ecig world want to blow the biggest clouds and don't take the time to learn why and how to do such things.

 

[jp_cfc09]

Ive been vaping for a few years so I do have a well grounded understanding of vaporizers and their working systems. I also graduated from college with an electrical engineering degree, but I can see why my join date and avatar may raise some alarm. Using matched batteries I cycled through a set checking their voltage every few minutes as well as their temperature. The batteries 'died' with the same matched voltage. I'm going to stick with my single 18650 vct3 in my mod, but this was just sort of an experiment. It just seems like there is a ton of ''DONT STACK BATTERIES'' talk being thrown out there without any sort of real explanation as to why. Thanks for all the replys!

mean reason is because its not as safe and can be dangerous if the user is not experienced. problem also lately is alot of new vapers joining jan this year and looking to sub ohm and do crazy things because they seen it on youtube. no one knows you so does not know how experienced you are and would be stupid to tell a new vapers to go ahead and get his head blown off because they never knew what they where doing.

most just come to the conclusion that you must be a new vaper from your jan join date and also the fact that you had to ask the question in general.

 

[Stosh]

Ive been vaping for a few years so I do have a well grounded understanding of vaporizers and their working systems. I also graduated from college with an electrical engineering degree, but I can see why my join date and avatar may raise some alarm. Using matched batteries I cycled through a set checking their voltage every few minutes as well as their temperature. The batteries 'died' with the same matched voltage. I'm going to stick with my single 18650 vct3 in my mod, but this was just sort of an experiment. It just seems like there is a ton of ''DONT STACK BATTERIES'' talk being thrown out there without any sort of real explanation as to why. Thanks for all the replys!

The why of it is that it can be a royal PITA to check the batteries before and after use to be sure that they are aging at the same rate, rotate their positions in your mod. Even if bought together there is no guarantee they came from the same production run. Difference in the internal resistance over time / the life of the batteries MAY vary, and very well may not, needs monitoring more than a single battery.

It can be done safely, if precautions are taken, and the much of the same monitoring should be done for a single battery. Stacking just makes the monitoring a bit more complicated...something that can be too easily ignored by many most vapers...