Just doing some quick math on an ohm's law calculator.
Lets say 3.2v loaded, and a basic 3 ohm atty(carto, whatever) gives you a 1.067 amps, or 1067mah drain. (3.41 watts if curious)
This would give you ~ 3.81C based what we know.
If they are LiPo (and i think they are, based on 3.7v nominal and 4.2v full charge) they should most likely have a higher C rating than that.
Ive done a lot of R/C stuff and C rating is pretty important in that case. But on another note those batteries can usually be 40-50C or higher in a lot of cases. Ive seen as much as 150C on the high dollar setups. Maybe more now as Ive been out of the hobby for around a year.
With the above mentioned case I would think that those batteries would maybe be in the 5-10C range?
I dont know for sure, as I dont have any in-depth 510 battery info sitting in front of me lol.
You can usually figure out an amperage draw with simple math and a known C rating though. mah X C = max discharge rate. One of my known R/C batteries is 5400mah and 40C (80C burst), or i can pull 216A continuous and 432A burst. Thats quite a bit of power in a little package... lol
Oh and it looks like I mmay have gotten a little carried away lol
