Battery Info Needed.. Series / Parallel mech mods

[Barkuti]

… I see no reason to take extra risk for a fraction of a second battery lag. The difference in performance just isn't worth the extra risk.

It's actually pretty easy, but you may have to arrange a in series voltmeters setup, at the very least, in order to have a way to independently check out each link. For 2S, simplest way would be a DPST switch or a momentary pushbutton driving the coil of an inexpensive low power 5V DPST/DPDT relay. Example: cathode (B-) to first voltmeter's negative lead, midpoint (B1) to first voltmeter's positive and second voltmeter's negative (via relay), and anode (B2/B+) to the second voltmeter's positive terminal (via relay). Pressing the button would drive the relay coil from the battery, which engages the voltmeters in series at once over the battery terminals. Button disengaged -> voltmeters off, 0 battery drain. Quite simple.
And/or get a suitable BMS. I recently ordered the 15A one here: surever9's 3A-15A 2S Li-ion Lithium 18650 Battery Cell BMS Protection Board 7.4V 8.4V Quite small.
The seller told me it uses Vishay Si4324 MOSFETs.

Cheers

 

[GBalkam]

It's actually pretty easy, but you may have to arrange a in series voltmeters setup, at the very least, in order to have a way to independently check out each link. For 2S, simplest way would be a DPST switch or a momentary pushbutton driving the coil of an inexpensive low power 5V DPST/DPDT relay. Example: cathode (B-) to first voltmeter's negative lead, midpoint (B1) to first voltmeter's positive and second voltmeter's negative (via relay), and anode (B2/B+) to the second voltmeter's positive terminal (via relay). Pressing the button would drive the relay coil from the battery, which engages the voltmeters in series at once over the battery terminals. Button disengaged -> voltmeters off, 0 battery drain. Quite simple.
And/or get a suitable BMS. I recently ordered the 15A one here: surever9's 3A-15A 2S Li-ion Lithium 18650 Battery Cell BMS Protection Board 7.4V 8.4V Quite small.
The seller told me it uses Vishay Si4324 MOSFETs.

Cheers

I think you kinda missed what I was saying.. about hybrid vs non-hybrid. I use the non-hybrid because they are much safer and you don't need to worry much if your positive pin is to short. The difference in performance between hybrid and non isn't enough to justify the extra risk involved. For example, with non-hybrid, I never have to worry if my pin is to short, since the non-hybrid has a floating 510 pin.

As for building a mod. I'm far to lazy. LOL.

 

[GBalkam]

The Samsung 25R has a 20 amp CDR (2500mAh). The LG HG2 and Samsung 30Q (3000mAh) both have the same CDR but slightly better mAh.

With a parallel configuration you get between 75-100% of the combined CDR, so with 25R that's between 30 and 40 amps to work with.
So using Ohms law 0.14 ohms at 4.2v will draw 30 amps from the combined pool giving you 126 watts.

With series configuration the voltage is doubled to 8.4 volts, but the individual CDR applies. You can use a higher resistance range for this configuration.
0.56 ohms at 8.4v drawing 15 amps giving you 126 watts.

Though in practice the Wattage will be far less than this due to voltage drop and battery sag. Both these builds will have the same runtime. Of the two I prefer series for instant ramp up and avoiding super low resistance coils.

So basically speaking, with series I build more wraps at higher wattage, and parallel I would shoot for lower ohms. Since I don't like going to low with my ohms, I think more wraps would be better suited for my purpose.

I've actually done a lot of studies on batteries etc before buying my first mech, and even more on battery safety. Now I don't recommend anyone to build at any resistance below 0.15, and suggest 0.3 to 0.2 as a decent starting point for new mech users. This from my own research, and talking to the shop owner that sells mech mods. Keeping in mind the term "safe" is relevant. Even a regulated mod is not 100% safe. Sorry, I couldn't find the actual thread, but 2 samsung 25r batteries shorted and vented in a regulated mod, due we think, to circuitry failure in the protection chip. So it is all about vaping at what you personally consider a "safe" area. Personally, for ME, I consider 0.1 to .012 and higher as "safe" (again, for ME, with the batteries and mod I use). To be quite honest, regulated mods offer much more options, such as warmer vapes, better flavor, etc. And are by far the safest mods to use.

I might never go to a multi-cell mechanical, but I do want to know everything I can about them to make the decision. Hence the post here.

 

[Barkuti]

I think you kinda missed what I was saying.. about hybrid vs non-hybrid. …

I just wanted to chime in with handy help for achieving a cost-effective and easy way to monitor the cells' state of charge.
With regards to vaping mods, mostly naive am I.
I'm not a vaper, I just immunized myself to the tobacco addiction… two years and three days ago. Exactly.
If I were you, I would concoct myself some special nasal spray. Discreet, pocketable, efficient, reliable, instant-rush… and cheeeeap. Ooops!

With a BMS, a single voltmeter in series with a pushbutton is all you need to monitor voltage/SoC. The circuit takes care of the rest.

Cheers

 

[GBalkam]

I just wanted to chime in with handy help for achieving a cost-effective and easy way to monitor the cells' state of charge.
With regards to vaping mods, mostly naive am I.
I'm not a vaper, I just immunized myself to the tobacco addiction… two years and three days ago. Exactly.
If I were you, I would concoct myself some special nasal spray. Discreet, pocketable, efficient, reliable, instant-rush… and cheeeeap. Ooops!

With a BMS, a single voltmeter in series with a pushbutton is all you need to monitor voltage/SoC. The circuit takes care of the rest.

Cheers

What does that have to do with the length of the positive pin on atomizers?

 

[Joergl100]

Kidding as usual.

 

[KenD]

Now I don't recommend anyone to build at any resistance below 0.15, and suggest 0.3 to 0.2 as a decent starting point for new mech users.

.5 is more of a decent starting point, and that's on the low side. Starting with .2 to .3, particularly considering that even quality resistance readers aren't all that accurate at low resistances, is just asking for trouble.

Sent from my M7_PLUS using Tapatalk

 

[Joergl100]

Ohmygod...how could I ever have survived unscathed with much lower omhed builds...down to 0.07 Ohms...with A123 26650s down to 0.05...

Mammamia...

I know what I am doing...and I also know what pain my batteries can endure!!!

THAT IS NO RECOMMENDATION TO OTHERS TO DO AS I AM DOING!

 

[KenD]

Ohmygod...how could I ever have survived unscathed with much lower omhed builds...down to 0.07 Ohms...with A123 26650s down to 0.05...

Mammamia...

I know what I am doing...and I also know what pain my batteries can endure!!!

THAT IS NO RECOMMENDATION TO OTHERS TO DO AS I AM DOING!

New mech users were recommended to start at .2-.3 ohms... What you choose to do was not the topic.

Sent from my M7_PLUS using Tapatalk

 

[GBalkam]

Ohmygod...how could I ever have survived unscathed with much lower omhed builds...down to 0.07 Ohms...with A123 26650s down to 0.05...

Mammamia...

I know what I am doing...and I also know what pain my batteries can endure!!!

THAT IS NO RECOMMENDATION TO OTHERS TO DO AS I AM DOING!

0.05 is well below my chicken limit. But I said the same thing pretty much in the cloud chaser forum. No resistance level is safe if you don't know what you are doing.

Definition: Hard core vapor... Eyeing the 1/8" aviation cables and thinking "Hmmm I wonder what the heat flux is at 4.2v" lol

 

[Joergl100]

 

[Ben85]

I love how someone can claim that they "know what they are doing" when they simply haven't had something go bang in their hands yet.

Do us a favour. When it does eventually go wrong, don't tell the guy patching you back up that it was because of an ecig. Don't need yet another story in the press where someone acts foolishly and then blames it on the gear they use. It gives vaping a bad name.

 

[DaveP]

Not knocking the preferences of any vaper, but for my money a regulated mod is the only choice. I've had a couple of mechs in the last few years, but they are in a box somewhere. I like to pocket carry and I want over current protection and a timed cutoff in case I sit down and accidentally activate the fire switch.