Low Voltage Cell Query

[Viruk]

I've just received my new Triade DNA250 and a set of brand new LG HG2s.
After inserting the HG2s the mod wouldn't turn on, if I held down the button I received the check battery and check atomiser warnings.

I assumed the new cells may just have dropped a little too low and may need to charge so put them onto a Nitecore D4.

Two of the cells showed a voltage I'd expect - around 3.6v, however one of them showed me a worryingly low voltage of 1.7v.

I took all the cells out of the charger, looked at the very low voltage cell for any sign of wear or visible damage and it looked ok. I then thought I'd test it in other slots on the charger to see what the voltage was reported as, I got a consistent voltage displayed and took a picture of the cell showing 2.79v (in case I need to return the cell for a replacement).

As it was showing close to 3v I thought I'd give it a few minutes on the charger and see what happened - or whether anything got too hot. Within 5 minutes (I wasn't watching every second) the cell was reporting over 3v. So I placed the other two cells in the charger with it.

After a couple of hours the "normal" two 18650s are just about at 4.2v and the initial low voltage one is showing 3.71v. There is no noticeable heat and no difference between the temperatures of the three cells (not scientifically measured - just using my hand to test temperature!).

A quick google hasn't yielded much in the way of useful information

On to the questions:
1. Has anyone experienced anything similar with new 18650s?
2. I have faith in the DNA boards safety features, but am I being naïve relying on the safety in the mod to protect me against a problem with this cell?
3. Does anyone have any advice in this situation? Am I taking an unnecessary risk using that set of cells?
4. Does anyone have any explanation as to what was going on?

Thanks in advance for any input

[Wayneo]

On to the questions: 
1. Has anyone experienced anything similar with new 18650s? Luckily no.

2. I have faith in the DNA boards safety features, but am I being naïve relying on the safety in the mod to protect me against a problem with this cell? Sorta. The DNA will protect you and itself, but having proven a dead cell with your charger, just buy one new one, so they're married. Married really only means they have been discharged the same number of times, for the exact same brand and type of battery.

3. Does anyone have any advice in this situation? Am I taking an unnecessary risk using that set of cells? Answered in 2. Buy one new LG HG2.

4. Does anyone have any explanation as to what was going on? Yeah, you have 1 dead battery.


Cheers man, just wait till you have that new battery before enjoying your mod. 

[Viruk]

Hi Wayneo,

Thanks for taking the time to respond.

Current update is that the low voltage cell is about 4.1v and although it appears to have started from a lower voltage, it is not showing any other signs of actually being dead. There is also no noticeable heat difference between that and the other two cells that completed their charge a couple of hours ago.

I'm currently considering testing it with the trio of new cells and monitoring to see if the voltage drops quicker than for the other cells.

I have other sets of HG2s I can use, so I'm not being impatient just to use the new mod - I can do that with one of several other sets of married 18650s. I am however, quite curious about what I was seeing with that particular cell and interested in whether it will hold charge properly and discharge at the same rate as the other two...

[Wayneo]

@Viruk sounds like a plan, man! Knock on wood, I haven't had any battery issues. 

[Viruk]

Quick update:

I've used the new set up a little last night, keeping an eye on the voltages in device monitor. Its stood unused overnight and then fired fine this morning. The voltages have stayed even across all the cells and there has been no noticeable heat build up anywhere.


 

This shot does show a very slight variance on one cell of 0.01v but that levelled out again within a few seconds.


I'm still interested in hearing from anyone who either has any information on safety concerns or if anyone has had a similar experience with a new 18650

[Wayneo]

@Viruk, looks just perfect man. I see you have it set at 100watts, and look at the ramp up to your temp. Just freakin perfect.

There are 2 different camps for TC.

1. Set your wattage high (like you did, and I do), and let the board do its job. OR
2. Set your wattage much closer to the actual usage, and play with punch and preheat.

2 different ways to skin the cat, neither is wrong, just different. 

Now if you really want to see just how great it all is, down in the bottom right hand corner, there's a button called 'puffs'. Set your mod down, click that button (I usually just choose 4 seconds) and your mod will fire, as if you were taking a 4 second vape. Go look at that smooth line, and how few watts are required to maintain that temp.

And with these boards (unlike many others) you should never lock the resistance (unless you have a shitty build)

[Viruk]

I find this way is better for SS316L, plus on that setup if I'm vaping non-TC (if I'm on anything other than a DNA board!) I use that setup at a little over 100W and it works quite well, but no other board comes close to the experience I had with the DNA200 and now with the 250

I did test temp control with the same build/atty combo on an RX200 and RX200S; while the latter is an improvement over the former its just way too unpredictable.

I've had a good experience with SS on the DNA200 for quite a while now, but since the SP2 update it just smoothed it out so much more at the desired temp.

I haven't gone back to titanium since those updates (yet) - I'm curious if that's seen an improvement like SS seemed to get; but I do like the ability to just swap on to a different mode in straight wattage mode when using stainless.

I've never locked the resistance of a build - and nor will I

What material do you use for TC? I don't really like nickel, I've only done a little experimentation with titanium and exclusively used SS316L when playing with stainless.

[Wayneo]

I'm mainly a 26g SS316L on all my mods (DNA's) and I find the exact same experience on all of them. I sorta standardized the screens, profiles, etc. on all, so I set my wattage at 75watts. Although right now I'm running some SS430 from Unkamen, and notice a bit quicker ramp up. The only thing I notice about that 28g SS430 (also from Unkamen) is that it is much springier than 316, and if I do more than a simple glow to remove the hot spots, I can deform the coil quite easily.

They also sent along some Titanium, but I just haven't wrapped any of that up yet, as I'm very happy with SS being so tasteless and working fine. I also have some Ni 200 Aspire coils which came with tanks that I've never tried.

I've got a 250 board on order, and will hopefully have some stabwood for it by the end of next week. I'll probably outfit it with a Lipo strictly because they have 2amp charging now, and no decent Reuleaux style battery sleds or 3D print options.

One idea that has been brought up before, but not implemented, was to have the pre-heat set as a % greater than the wattage, which is a fantastic idea. 

Cheers man.

[Viruk]

I haven't tried any SS430 yet - I'm a little put off if it deforms easily. I've never had a problem with SS316L, but a friend of mine managed to deform the same coils by glowing a little too much.

I'm using chunky coils - hence the high pre-heat being high; fused Clapton with 2x26g core with 30g wrap. In dual coil set up I reliably get 0.11-0.12ohms and the high wattage is good.

I've used the same Clapton wire today in a single coil setup on the Pharaoh for the first time - that was delivered with the Triade yesterday but I only built on it today. I've dropped wattage on that as resistance is more than double my usual for that wire.

I haven't had the best results with a higher punch setting, although as the current setup has been great I haven't experimented with punch since much earlier f/w versions.

With regard to the Aspire coils - generally I like their coils although I don't use them very often these days. I liked their SS coils for the triton and the more recent Clapton coils, but I never got on with the Ni200 triton coils - I just didn't like the taste as much as when using their other coils.

I've had my Reuleaux DNA200 for about a year and still use it every day, but after a little over 24 hours of use of the Triade I am quite impressed. The main thing for me was having the triple 18650 option to have great capacity, but overall its very similar in all the right ways, and one not so great way!
Everyone has their own preferences, but I'd take a guess that the Triade would suit you just as well (or otherwise) as the Reuleaux.