reyn3545

I've been flying brushless electrics for a year or so, but I don't fully understand battery ratings as they relate to an ESC and the motor they drive. I can certainly understand that a motor with 400 watts max burst would need an ESC and throttle management to stay below that level. But, I don't uderstand how the "C" rating on batteries relates to speed controllers.

Lets say you have a 360 watt motor, with a 35 watt ESC.

One battery, a 2100MaH 3s1p, 15c - 24c
Another battery, 2100MAh, 3s1p, 25c - 50c

I know the 25c - 50c battery will deliver more power to the ESC, but what exactly is the "c" rating, how is it calculated, and should I expect that given both batteries in the above scenario are 2100 MAh, would the 25 - 50c battery run down faster?

I know this question has probably been asked 1000 times... so if someone could point me to the right page.... I'd appreciate it!

Fliprob17

The higher the C rating the more amps the battery can handle and is capable of delivering. Take those batteries you mentioned: 2100mah 15C - divide the 2100mah by 1000 to get amps = 2.1, then multiply that times the C rating = 2.1x15=31.5 amps that the battery can deliver under a continuous load. The second C rating number, 24 in this case, is the max. 15 second burst rating for the pack.

The difference between a 15C pack and a 25C pack is that the 25C pack can handle and is capable of more amp draw, that's it. If they are both operating under the same amp draw, they will drain down the same. The C rating has no impact on how fast the battery drains. Just how much the battery can handle.