Triple 18650s in parallel on a DNA200

[Deepinmind]

I'm considering getting the Lost Vape Triade mostly for aesthetic and ergonomic reasons. I don't usually go above 70W on my builds and therefore would have little use for the full 11.1V the Triade offers. I DO however want to have a battery setup that has long Watt Hour rating. I have come to the conclusion that modding the battery sled to a parallel set up would be ideal. I have over 10 years experience with electrical repair/engineering and soldering so I feel confidant I can do this safely. My questions are Is this possible to do with the DNA200 configuration in the Triade? What, if any, limitations would this setup pose besides lower wattage capabilities? Would the DNA board still be able to monitor and charge the batteries properly? (Balanced charging?) Would my battery profile need to be adjusted to maximize efficency, or even have the mod work at all? Thanks in advance, I've only been using regulated mods for the past year. I've been using mech mods exclusively for the past 5 years, so I'm still catching up on the learning curve. Mikey P

[dwcraig1]

Well first off the batteries capacity will be the same whether parallel or series
Example: 3 2500 mah 18650's = 27.75 watt hours no matter if parallel or series.
The board will only draw up to 23 amps from the batteries but because it's a buck converter it will output as high as 55 amps @ 9 volts.
Edit: besides it won't work, 7.4 - 11.1 volt pack yes, 3.7 volt pack no.

[VapingBad]

Deepinmind said:

I'm considering getting the Lost Vape Triade mostly for aesthetic and ergonomic reasons. I don't usually go above 70W on my builds and therefore would have little use for the full 11.1V the Triade offers. I DO however want to have a battery setup that has long Watt Hour rating. I have come to the conclusion that modding the battery sled to a parallel set up would be ideal. I have over 10 years experience with electrical repair/engineering and soldering so I feel confidant I can do this safely. My questions are Is this possible to do with the DNA200 configuration in the Triade? What, if any, limitations would this setup pose besides lower wattage capabilities? Would the DNA board still be able to monitor and charge the batteries properly? (Balanced charging?) Would my battery profile need to be adjusted to maximize efficency, or even have the mod work at all? Thanks in advance, I've only been using regulated mods for the past year. I've been using mech mods exclusively for the past 5 years, so I'm still catching up on the learning curve. Mikey P

In short no, the DNA 200 needs at least 2 cells in series so parallel is not an option with 3 cells, you could swap the board for a DNA 75, but the 200 is more efficient and you would shorten runtime slightly.  There is no reason that parallel would give you longer run time, Watt hours are Watt hours and each battery would need to supply a third in either config.

For long run time, high Watt hours since you are not running high wattages 3 x Samsung 30Q or LG HG2 batteries would be a good choice IMO giving you around 33 Wh over 3 time what the smaller LiPo designs have.   Always buy from a reputable source there are fakes about.

[Deepinmind]

dwcraig1 said:

Well first off the batteries capacity will be the same whether parallel or series
Example: 3 2500 mah 18650's = 27.75 watt hours no matter if parallel or series.
The board will only draw up to 23 amps from the batteries but because it's a buck converter it will output as high as 55 amps @ 9 volts.
Edit: besides it won't work, 7.4 - 11.1 volt pack yes, 3.7 volt pack no.

Everywhere I have read about series and parallel it has stated that series adds the voltages together to give a higher output than one cell alone, but leaves the Amp rating and mAh the same as a single cell. Ex: 3X 18650 2500mAh 25Amp @ 3.7V = 11.1V 2500mAh 25Amp output from the batteries And that parallel did the opposite, leaving the Volts as one cell, while adding the amps together and the mAh together. Ex: 3X 18650 2500mAh 25Amp @ 3.7V = 3.7V 7500mAh 75amp output from the batteries. We're all those credible websites and books incorrect??

[dwcraig1]

Your post above is correct but as I stated the board will only draw 23 amps from the pack. Also watt hours are the same in both examples. Watt hours is going to be what determines how long the pack lasts before needing recharged.

[Deepinmind]

dwcraig1 said:

Your post above is correct but as I stated the board will only draw 23 amps from the pack. Also watt hours are the same in both examples. Watt hours is going to be what determines how long the pack lasts before needing recharged.

So then who cares about mAh? Why would they even list it on a battery if it doesn't make much of a difference with multiple cells? Why do my Parallel setups last longer before needing a charge even when I build super low, if both setups have the same Wh rating? None of this makes sense. Multiple resources have stated that Wh are different on parallel and series setups. I mean this website says it outright. "When batteries are connected in parallel, the capacity in terms of amp hours and kilowatt hours doubles. Voltage however remains the same." http://all-about-lead-acid-batteries.capnfatz.com/all-about-lead-acid-batteries/lead-acid-battery-fundamentals/what-are-parallel-batteries/ Is this only true for lead-acid batteries???

[dwcraig1]

It would pertain to all cell types.
To be more clear perhaps, two (same) cells whether connected in a series or parallel would have the same watt hours when paired.
 https://milliamps-watts.appspot.com/

[Spector NS5 RD]

Deepinmind said:

So then who cares about mAh? Why would they even list it on a battery if it doesn't make much of a difference with multiple cells? Why do my Parallel setups last longer before needing a charge even when I build super low, if both setups have the same Wh rating? None of this makes sense. Multiple resources have stated that Wh are different on parallel and series setups. I mean this website says it outright. "When batteries are connected in parallel, the capacity in terms of amp hours and kilowatt hours doubles. Voltage however remains the same." http://all-about-lead-acid-batteries.capnfatz.com/all-about-lead-acid-batteries/lead-acid-battery-fundamentals/what-are-parallel-batteries/ Is this only true for lead-acid batteries???

capacity/watt hours is the same from either parallel or series configured cells. 3 cells is series have the exact same capacity/watt hours as 3 cells, of the same voltage and mah, wired in parallel. FACT - law of physics
what DOES come into play is the efficiency of the voltage conversion. some DC DC converters are more/less efficient than others.

see for yourself........this is a handy watt hour calculator i use

https://milliamps-watts.appspot.com/

[VapingBad]

Deepinmind said:

So then who cares about mAh? Why would they even list it on a battery if it doesn't make much of a difference with multiple cells? Why do my Parallel setups last longer before needing a charge even when I build super low, if both setups have the same Wh rating? None of this makes sense. Multiple resources have stated that Wh are different on parallel and series setups. I mean this website says it outright. "When batteries are connected in parallel, the capacity in terms of amp hours and kilowatt hours doubles. Voltage however remains the same." http://all-about-lead-acid-batteries.capnfatz.com/all-about-lead-acid-batteries/lead-acid-battery-fundamentals/what-are-parallel-batteries/ Is this only true for lead-acid batteries???

Batteries store energy.

The first law of thermodynamics doesn't say anything about series or parallel, energy is, you cannot create or destroy it, only convert it.

Wh vs Ah, Wh just takes the combined cell voltage out of the equation, they are the same thing, but wh makes it far easier to compare different set ups.

You can't hold chunky responsible for bad info you read or misread, sorry if that comes over harsh I'm sure you are a good guy but...

[dwcraig1]

First 3 2500' in parallel, 2nd 3 2500's in series
 
 

[Deepinmind]

VapingBad said:

Batteries store energy.

The first law of thermodynamics doesn't say anything about series or parallel, energy is, you cannot create or destroy it, only convert it.

Wh vs Ah, Wh just takes the combined cell voltage out of the equation, they are the same thing, but wh makes it far easier to compare different set ups.

You can't hold chunky responsible for bad info you read or misread, sorry if that comes over harsh I'm sure you are a good guy but...

Yeah, I didn't mean to come off as a dick. My bad. I'm having a rough day. Shouldn't have taken it out on you guys. On the same note, I was recently told that two cells in parallel roughly doubled the amp rating, BUT adding a third cell doesn't triple the amp rating. So.....did math just stop working after two cells, or is there some kind of limitation after two, or with odd numbered cells?

[VapingBad]

I think the amp rating advice is with parallel cells is just sensible stuff not pushing the weakest cell too far and allowing for wiring loss and nothing to do with the physics.  The main truths are cells in parallel will all be at the same voltage and cells in series will all be at the same current, so the weakest cell in parallel could get too high current demand and the weakest in series would be at a lower voltage.

[thomasck]

As a regulated mod, series or parallel would not make much difference. As in series the board will work with higher voltage and smaller amperage, and in a parallel configuration will work with a increased amperage and lower voltage. So, at end of the day, you are going to achieve same results, but just in a different way..