Welcome to PhantomPilots.com

Sign up for a weekly email of the latest drone news & information

Battery discharge rates

Discussion in 'Other DJI Multi-Rotors' started by darwin-t, Dec 25, 2014.

  1. darwin-t

    Joined:
    Apr 28, 2014
    Messages:
    513
    Likes Received:
    5
    I'm starting to look for batteries for my F550 build.

    I found several 5000 mah batteries, with discharge rates of 20c, 25c, 30c, 40c, 45c, and 60c

    I also found a 5800 mah with a discharge rate of 30c and an 8000 mah battery that has a discharge rate of 30c

    My build uses E300 motors, DJI ESCs and a Pixhawk flight controller. NO additional weight right now, but will quickly add a GoPro and eventually an FPV system. MAYBE a 200 gram gimbal later

    Could someone please tell me which battery would be best, or better yet, explain how to figure what discharge rate is needed?

    Thank you very much!
     
  2. OBX Kevin

    Joined:
    Jul 13, 2014
    Messages:
    40
    Likes Received:
    0
    Location:
    Annandale, Virginia
    I'm in the same boat that you are. I currently own a Phantom 2 and the batteries are a no brainer. (lol) I have a F550 on order with the E300s, Naza M V2, and will be using a FrSky X8R receiver. I'll be adding a gimbal (to be determined), GoPro and FPV. I'm looking for any suggestions on batteries since the market is quite vast and I question if some batteries are reliable.

    Keep us posted on your build. Maybe we can swap build stories. I'm also looking for any advise or suggestions.
     
  3. ladykate

    Joined:
    Jan 7, 2014
    Messages:
    994
    Likes Received:
    7
    Location:
    Bellevue, NE
    You can figure worse case and add a slight safety margin. The ESC from DJI for the 300 can safely draw 18 amps. Six of them will safely draw 108 amps total. Most ESCs will allow you to surge a bit higher but you shouldn't be doing that for any extended period (meaning more than a few seconds). The E300 can draw 15 amps according to the DJI website.

    So... your ideal power for the setup would be one that can supply between 90 and 108 amps safely and continuously.

    A 5800 with a discharge rate of 20c can do about 101 amps without pushing it. (20 x 5.8 amps).

    I use Gens Ace 5300 35C on my 550 and they are about the max I want to use for the weight. I think anything from 3000 to 5000 would be fine (30C min for me). You will find people who go beyond that in both directions so opinions will vary. If you get a 20C then you should probably get a battery big enough to carry the amps.

    Generally, the higher the 'C' rating, the more expensive the battery. The higher the AUW, the more amps required to carry the load.

    If your battery or motors are getting hot, then you have a problem and should resolve it (weak battery will result in a hotter battery, heavy AUW will result in warm motor/ESC/battery.)
     
  4. darwin-t

    Joined:
    Apr 28, 2014
    Messages:
    513
    Likes Received:
    5
    Thank you very much. Now I know exactly what i need