Stacking 18350s

[jumper]

Has anyone tried stacking 350s in their copper mod? I would like to do that but don't know if it's a good idea or not. I use stacked 350s in my Vamo and it works great.

[Breaktru]

Yes, in my Side x Side Mod

[jumper]

cool... I prefer to stack them but didn't know if it was a good idea for copper mods. I only use 350s and prefer it over the 650. Nice mod by the way. Like it a lot

thanks for the info!

[Breaktru]

In a mod with 2 batteries in series and NO step down variable voltage regulator, I would not advise it. 7.4v to 8.4v is way too much voltage. You would need a high resistance atty.
The Side x Side shown uses a Step Down Regulator

[jumper]

Dummy me, I can't remember which way series and parallel go. But the way I'm doing it on the Vamo is just normal. Nothing changed The Vamo only goes up to 6v. so I think I'm cool. However, I did pop a coil in it the other day at 6v.  But the coil was showing 4.5ohms and was in the "green" so I thought nothing would happen, but it did... oh well. I don't know if the Vamo has a step down or not. You would think so?? Speaking of my Vamo... I have the gun metal one and my finish is finally started to come off... bummer. But I knew it was going to happen sometime... sigh.

[redwolfe]

The Vamo has a step-down and boost converter in the same chip. I personally advise avoiding stacking 350s because there is no reason to if you can get the same or nearly the same results from a single battery.  Also if you must stack, use safer chemistry IMR cells.

[jumper]

The Vamo has a step-down and boost converter in the same chip. I personally advise avoiding stacking 350s because there is no reason to if you can get the same or nearly the same results from a single battery.  Also if you must stack, use safer chemistry IMR cells.

Hi Red, I know that there are some people who say stacking is not good, but I've also heard from other people who say it's ok. One of the things I like about the 350s is they charge faster. I only have 1 650, but 2 sets of 350s. Tomorrow I'm getting 2 650s and 2 more 350s. I been using the stacked batteries for a while now, but I thought when I first used the 650, it didn't "seem" to have as much power. Don't know if that's true or if it was just me. I AM using IMR cells though.

What I wish we had was some kind of scientific proof that says stacking is bad because.... or is ok because... My best friend stacks too and has never had any problems. I do appreciate your comments and concerns though. And it's possible that you may be right. I do seem to pop a few coils here and there and that might have something to do with it. I don't know. If I knew that stacking was causing that, I would definitely switch to a 650 for sure.

[jumper]

In a mod with 2 batteries in series and NO step down variable voltage regulator, I would not advise it. 7.4v to 8.4v is way too much voltage. You would need a high resistance atty.
The Side x Side shown uses a Step Down Regulator

I was going back over this thread and was reading your comment again Breakthru. And now I get it. I also may have misunderstood Red's post about stacking. He may have been talking about in a copper mod with NO step down vv regulator. I "thought" he was just talking about "in general". If you were talking about the copper mod, I apologize Red

So now I know... no stacking in my upcoming copper mod. Will have to wait until I do a vv one at least (as far as I'm understand this). I appreciate all the info about this from you guys. I'm still learning and I'm sure I'm the junior member here

thanks a bunch to both of you...

[redwolfe]

Hi Red, I know that there are some people who say stacking is not good, but I've also heard from other people who say it's ok. One of the things I like about the 350s is they charge faster. I only have 1 650, but 2 sets of 350s. Tomorrow I'm getting 2 650s and 2 more 350s. I been using the stacked batteries for a while now, but I thought when I first used the 650, it didn't "seem" to have as much power. Don't know if that's true or if it was just me. I AM using IMR cells though.

What I wish we had was some kind of scientific proof that says stacking is bad because.... or is ok because... My best friend stacks too and has never had any problems. I do appreciate your comments and concerns though. And it's possible that you may be right. I do seem to pop a few coils here and there and that might have something to do with it. I don't know. If I knew that stacking was causing that, I would definitely switch to a 650 for sure.

Well with IMR cells, it's fine, but 3+ years ago when IMR's were not as readily available, many, including me, stacked Li-ion cells. Ultrafire, trustfire, etc. and some of those cells got scary if they caught a short from the atomizer. Stacking cells (putting them in series) doubles power but the mah and amp discharge remain the same while putting cells in parallel doubles the mah and amp discharge but keeps voltage at 3.7V. So those cells that did not have a high enough discharge for the atomizer went scary if you weren't careful. There are many stories out there about batteries going scary.

[CraigHB]

The stigma from stacking cells comes from the use of 3.2V LiFePO4 cells.  Since cell voltage is lower, it's possible to use this configuration in a mechanical mod with a standard resistance atomizer.  However, the issue is that the CR2 cells typically used for this are not rated for atomizer currents.  They're severly overloaded and there have been a number of reported incidents of battery fire.  A few have suffered actual explosions causing serious injury.

Stacking properly rated cells is no more hazardous than using them single.  If that were not the case, laptop computer batteries would not be possible.  They use two two stacks of 4 cells in series.

In terms of the Vamo controller board, using stacked cells bypasses the booster part of the circuit so you get better efficiency with them.  However, the charge capacity of a single 18650 is higher than two 18350s in series.  It's kind of a wash, efficiency is higher with the stacked cells, but charge capacity is higher with the single cell.  I couldn't say which would provide better run time without bench testing both configurations.  I'd say single or dual cells is more a matter of convenience than anything else and that's probably why they provide the option.

[jumper]

Well with IMR cells, it's fine, but 3+ years ago when IMR's were not as readily available, many, including me, stacked Li-ion cells. Ultrafire, trustfire, etc. and some of those cells got scary if they caught a short from the atomizer. Stacking cells (putting them in series) doubles power but the mah and amp discharge remain the same while putting cells in parallel doubles the mah and amp discharge but keeps voltage at 3.7V. So those cells that did not have a high enough discharge for the atomizer went scary if you weren't careful. There are many stories out there about batteries going scary.

I understand now. I've looked at the pictures of some fried homemade mods and it's not a pretty sight. So I know what you mean by "scary". Thanks for clarifying the parallel and series thing for me. I am not an electronics person, but need to learn some basics if I'm going to mod. I have to admit that most of the diagrams post here, I don't understand. If they're simple I can though. That's one reason I wanted to do Breakthru's 3.7 "plain" mod. I could understand it more than the others. I'll get it eventually as time goes on. When I finish this message I'm going to look for basic electronics things on the net.

Thanks for helping... I need it. I don't want to be blind or stupid when it comes to building mods. I don't want anything "scary" happen to me. That's for sure. Well... going to do my search now and see if I can educate myself about these things a little more

[jumper]

Thanks for the info Craig. I only started vaping since Feb. of this year so I don't have the history that you and Red have. My Vamo is my first decent mod. I started out with a eGo Redux kit, then got a spinner and from there went to the Vamo. Although I haven't tried any other decent mods, I love the way the Vamo is working for me, and it didn't have a Provari price tag

I think that when I get more than 1 650 tomorrow, I'll try using a single battery and see how it goes. If I were on a trip or something, I would think that the 650s would be better. Right now I'm at my desk most of the time so using 350s is not an issue. Once when my lady and I were going somewhere, I didn't take extra batteries or remember to switch to batteries that were charged when I left the house. As a result, the Vamo quit working on me and I couldn't vape until we got back home.

Hope I'm not rambling too much here... Really appreciate your help and clarification

[CraigHB]

The Vamo does work pretty well, however you kind of get what you pay for.  You're not going to get the robustness and longevity out of it that you would a more expensive mod.  In terms of performance, you're probably not going to see much of difference with an expensive mod.  What you're paying for is the build quality.  In any case, the Vamo should serve you well until it wears out or breaks.

There is a lot of history with vaping when it comes to safety.  Lots of people have found things out the hard way.  Li-Ion cells carry a risk since they can catch on fire if mishandled.  They have varying degrees of safety so from that standpoint, you should be aware of what you're dealing with.

A quality removable cell with a proper rating is about as safe as you can get.  Other cells are not as safe.  Chinese devices like eGos and cig-a-like devices are not as safe as mods with removable cells.  They have a higher incidence of fire.  In fact, I've only heard of one incident of battery fire with a protected ICR or IMR removable cell, but many incidences with others.

[jumper]

I understand where you're coming from about build quality. I know the Vamo is on the low end, but I'm PO (lol). That's just one reason why I wanted to learn how to build my own. If I build my own and it breaks, hopefully I can fix it without too much trouble. My friend just bought a Provari and this is what he said to describe the difference between what he was using and then the Provari. He said, "It's like parking your old car and getting into a Ferrari". That let me know that build quality does make a difference. I am pretty careful (gentle) with the Vamo though, so I'm hoping I can get more mileage out of it than normal.

I've read about the Li-Ion cells and that they were NOT a good thing. But I didn't know about the eGo type devices being edgy. I'm glad I've moved away from that type of vaping. When it comes to cells, I was lucky enough to have my friend (who got me into vaping) to help out. And because of that, I've always had the right cells. I do thank you and everyone else for pointing me in the right directions. "Knowledge is Power". And with all the help I'm getting, I'm learning a lot more about things.

Thanks a bunch

[CraigHB]

I wouldn't say they're "not" a good thing.  They are a brilliant invention actually.  They store much more energy for their weight and volume than any other type of rechargeable cell.  A quality Li-Ion cell is actually no more hazardous than a lead-acid battery.  Those are also pretty common and you find in them in devices like uninteruptable power supplies, emergency lighting, and of course your car.  Lead-acid batteries can do nasty things when mishandled as well.  The big disadvantage with the Li-Ions is that Lithium is volatile so if the cell is mishandled or if the cell is defective bad things can happen.

If you stick with quality cells and quality chargers and take proper care of your cells there's actually very little chance you'll ever see a problem.

[pnguin]

I number cells with tape and a sharpy when I stack them and rotate the cells each time I reinsert them in the mod. I don't know if it is any safer but at least the cells are wearing equally.

[jumper]

That's interesting because I do the opposite. I try to make sure they go back in the same way they came out. I thought that would make them more stable. Is it better to swap them? I don't really know much about how batteries work.

[pnguin]

I am no expert but most of the stuff I have read says to rotate them. Check the battery section on ECF, lots of good info there.

[Breaktru]

One battery always depletes more when batteries are in series. And it is a good practice to rotate them after each charge. I use to rotate them mid use. If I remember correctly, it was the battery connected to the negative of my mod that depleted the most.

[jumper]

I appreciate this guys! I will have to start swapping my batteries around now. Anything that gets more life out of them is a good thing