14650 7.4v 1050mAh vs 18650 3.7V 3120mAh

Apologies if this is already answered somewhere, but I could not find an answer to this in any of the FAQs; and despite having two builds under my belt, and the electrical engineering part of this whole process is still new to me.

Basically: What are the pros and cons of these two batteries?

From what I can glean from some basic Googling, 14650 7.4V 1050mAh has more "potential power", and the 18650 3.7V w/ 3120mAh has more "total power."

So is this basically a question of current vs. capacity? (I REALLY hope I am using those terms correctly LOL)

I.E. the 14650 will run the saber brighter/louder for less time, and the 18650 will run the saber dimmer/more quiet for a longer time? And if so is it really that noticeable?

Is this correct?

If it matters, I am trying to wire:
PCv3
PEx
Luxeon RGrB LED
RGB Crystal Chamber LED
4 Accent SMD LEDs

and POSSIBLY going "all out" on the board and wiring:
Power On Indicator LED
2 Power On Progressive LEDs

Thanks so much in advance!

Your example 14500 will have approximately 7.8Wh (volts * amp hours = watt hours) while the 18650 will be 11.5Wh. The 18650 has more power available.

The LEDs will not be brighter unless you plan on running them extra hard and limiting their life, all of the LEDs will require at most 3.7v @ 1000mah (green) or less, so the 7.4v needs to be brought down to the proper operating range. Some of the electronics on the board will be tolerant to a higher voltages, but many of the components require 3.3v. The amp may be able to drive somewhat louder with higher voltages available, but even that requires less than 5.5v. (these are general numbers, I'm not sure what the exact chips are on the PCv3) The PCv3 is quite an old board at this point, the 3.7v hack removes voltage regulator that would bring the 5.5-11v supply down to the operating range of the board.

The indicator, crystal, and accent LEDs will require even lower voltages and only modest current, they are not really a factor compared to the other items. if you have all 10 proposed LEDs running at full blast that would pull about 200mah, a bit less significant, but if you are planning on running off of a 7.4v battery then you will need to use a higher value current limiting resistor which just wastes more power as heat, so the higher capacity 3.7v battery wins doubly.

This is why I come here.

For answers like this.

I wish this was Reddit so I could guild you.

Thank you so much for the amazing answer, I really appreciate it.

:cool: