Breaktru Forum

eCigarette Forum => Battery => Topic started by: dc99 on October 29, 2016, 06:46:08 PM

Title: Choosing the right lipo
Post by: dc99 on October 29, 2016, 06:46:08 PM
http://www.bigalsmods.com/product-p/1001.htm
I have a few of these boards laying around and got a bit puzzled on how to choose the correct battery for them. In series 18650 do you need 20a,30a or what? If using say a 3s lipo which would be the best. 20C, 30C, 40C and so on. Is there a formula for calculating the requirements?
If you made one with two 18650's in series and used 30a capable batteries could you push it to far with the 1K pot? There has to be a way to know the limits.
Title: Re: Choosing the right lipo
Post by: d_walk on October 30, 2016, 09:11:32 AM
I was going to recommend the EFAN 60A max 18650 batteries but then came across this video:

https://www.youtube.com/watch?v=FkpPu_iEy7A (https://www.youtube.com/watch?v=FkpPu_iEy7A)
Title: Re: Choosing the right lipo
Post by: Breaktru on October 30, 2016, 09:27:41 AM
This is a formula to figure amp ratings:
Battery ma rating x C rating / 1000 = Amperage
Example: 2000ma x 30C / 1000 = 60A

Big AL states:  Maximum recommended current is 60A
Title: Re: Choosing the right lipo
Post by: jomurp on October 30, 2016, 09:54:53 AM
If I remember correctly, 2 batteries in parallel will double the ma and amperage rating and voltage will remain the same. In series they will remain the same ma and amp rating but the voltage will add.
Two 2000ma 60A batteries in series will be 2000ma, 60A at 7.4 volts and two in parallel will be 4000ma, 120A at 3.7V. I think
Title: Re: Choosing the right lipo
Post by: dc99 on October 30, 2016, 04:13:22 PM
I understand how to calculate the battery mah and amperage. My question is, can you draw more than the batteries are capable of? For instance: If you built it with two 18650's in series (say 30A batteries), could you crank it beyond the 30A limit? I understand the output is determined by the input but just like a regulated mod you still have to have a battery capable of the mods output.  Without knowing the output how can you calculate what amperage you will need to stay in the safe zone? 60a is just the maximum current he recommends for any configuration. We all know that would be impossible with two 18650's in series because there aren't any batteries that can do more than 30a
Is this in the right ballpark. https://hobbyking.com/en_us/turnigy-nano-tech-1800mah-2s-65c-130c-lipo-pack.html
Title: Re: Choosing the right lipo
Post by: Breaktru on October 31, 2016, 06:45:08 PM
I am not too familiar with PWM mods. Haven't built any.
I think the best advise would be to ask the builder of the circuit board. Big Al. Sorry dc99. I wish I could offer a better response.
Title: Re: Choosing the right lipo
Post by: dc99 on November 01, 2016, 08:05:17 PM
Thank you sir. I spoke to him and according to him the only thing that matters is the coil (load) you put on it. If you use 30a batteries then don't build a coil that would exceed that. If using a 3S 50C lipo then don't build anything that would exceed that. From my understanding you treat it more like a mechanical as far as the build you put on it.
I do have a question for you on lipo's . Whats the difference between a regular and a nano? Any particular brands that are better than others for vaping. As you can tell, lipo's are not my thing but you don't learn if you don't ask
Title: Re: Choosing the right lipo
Post by: Breaktru on November 02, 2016, 12:34:19 PM
According to the manufacturer (Turnigy):
More than just a fancy name. TURNIGY nano-tech lithium polymer batteries are built with an LiCo nano-technology substrate complex greatly improving power transfer making the oxidation/reduction reaction more efficient, this helps electrons pass more freely from anode to cathode with less internal impedance.
In short, less voltage sag and a higher discharge rate than a similar density lithium polymer (non nano-tech) battery.


I use Turnigy Nano-Tech Li-pos and buy them from Hobby King. When ordering make sure you select from their USA warehouse. Otherwise they may ship from China and will take forever to receive.

Here are two videos that contradict which li-po is better. Regular or Nano-Tech. See:
https://www.youtube.com/watch?v=KvIaLN4AVlE (https://www.youtube.com/watch?v=KvIaLN4AVlE)
https://www.youtube.com/watch?v=fucFhqx-hHw (https://www.youtube.com/watch?v=fucFhqx-hHw)
Title: Re: Choosing the right lipo
Post by: dc99 on June 18, 2017, 12:56:36 PM
I have a new project that I need a bit of help on. I need a 1S pack to power a DNA75 and all the ones I can find are either really low mah or there way to long. Why cant they just make one in similar size to the 3,6S sizes? Anyway, I have approximately 72x45x23mm to play with. I know 18650's would be easier but my friend wants lipo's. Any ideas?
Title: Re: Choosing the right lipo
Post by: Breaktru on June 18, 2017, 02:27:09 PM
I have a new project that I need a bit of help on. I need a 1S pack to power a DNA75 and all the ones I can find are either really low mah or there way to long. Why cant they just make one in similar size to the 3,6S sizes? Anyway, I have approximately 72x45x23mm to play with. I know 18650's would be easier but my friend wants lipo's. Any ideas?

What I did was parallel (3) 1000ma li-pos as shown here: http://breaktru.com/smf/index.php/topic,1628.msg20893.html#msg20893
The physical size of the Turnigy is 65 x 34 x 6mm. Three would give you 65 x 34 x 18mm.
Turnigy Li-Po (https://hobbyking.com/en_us/turnigy-1000mah-1s-20c-lipoly-single-cell.html)
Title: Re: Choosing the right lipo
Post by: dc99 on June 18, 2017, 03:11:26 PM
That will work great. Thanks.
Title: Re: Choosing the right lipo
Post by: dc99 on June 18, 2017, 09:26:01 PM
Out of curiosity, how's the run time versus a good 18650? 
Title: Re: Choosing the right lipo
Post by: Breaktru on June 19, 2017, 10:51:50 AM
I see a bit more run time but not a tremendous difference.