Discussions

regarding li-ion batteries

Posted by srinivasan m on August 26, 2016 at 9:47pm

Guys i m planning to power my drone using li-ion batteries. I'm planning to connect 6s 18650 batteries in series (3600Ah) and set of 20 to power 72Ah, My ESC requirement is 22 v. 

6s=6*3.7=22.2V

20P=20*3.6=72A

What is the BMS i require and what is the buck controller should i use for making it as 22V.

You need to be a member of diydrones to add comments!

Join diydrones

Email me when people reply –
Follow

Replies

  • srinivasan m August 30, 2016 at 11:23am

    thank you for your suggestions.

  • srinivasan m August 28, 2016 at 7:56pm



    James said:

    18650's are about 50g each.
    https://na.industrial.panasonic.com/sites/default/pidsa/files/ncr18...

    If you have 20g 18650's @3600mah, please share the details!!

    For stability you realistically shouldn't design for hover power greater than 65% throttle, as you will run out of control margin in wind, and have very limited translational speed.

    I'll leave you to it: enjoy doing some research, and don't assume that you'll get it right in the first build :)
    I saw gemini v-2 specs. So ,im planning to build one like that.

    Gemini V-2 Specs:
    Wing: 3.2 M Span / Aspect Ratio: 10.77 / 1 Airfoil: GOE 398 / 14% thick
    Area: 96,000 cm. square OR 1488 square inches
    Weight of airframe structure: 4 LBS, 9 OZ
    Empty weight: 7 LBS
    Minimum flying weight: 15 LBS / 6.8 KILOS
    Gross Weight: 20.75 LBS / 9.4 KILOS
    Wing loading: 23-32 OZ. -SQ. FT - 71-98 SQ. D.M.
    Endurance: 4+ HRS (With "Tesla" Style Lithium Ion battery pack)
    Distance: 160 KM (Linear)
    Cruise speed: 40-50 kph
    stall speed at max gross weight: 22 mph / 35.4 kph
    Ceiling: 13,000ft+ / 4,000meters+
    Best Loiter Speed: 42kph
    Battery: "Tesla" style, lithium Ion pack 64 Ah (for best performance)
    Amp draw at 42kph: 13.5 -17AMPS@12v
    Motors: 2X E-Flite "Power 15" 950kv out-runner electric motors
    Props: 13 X 8P and 13 X 8E APC Thin electric 2 bladed props ( counter rotating inwards at the top)
    Esc's: Castle Creations - Phoenix Edge 50 AMP X2
    Servos: Hitec HS 225MG X5
    Wheels: 3"Nose wheel / 3.25" Main wheels
    Features:
    4 SWAPPABLE PAYLOAD OPTIONS:
    1 Large payload bay, (fits 2 compact DSLR cameras)
    1 Small payload bay, (for object drop or observer cam)
    Both payload bays have an unobstructed downward view of the ground, for mapping missions.
    2 Hard points on the wings
    ~Modular 6 piece Design - Fits in the trunk of a small car, and assembles in about 10 minutes.
    ~Easier to fly than most trainers.
    ~Low Pilot / Autopilot workload, Due to stable flight dynamics.
    ~Easy to build and repair with common hobby materials.
    ~Robust design, Ideal for commercial applications.
    ~Overall layout is ideal for keeping sensitive receivers far away from noise producing video transmitters, or telemetry modules.

    The plane uses 6.4 empty weight and it can hold upto 9 kgs and it almost meet my requirements. Do u believe that stability might be an issue here. I m require a bms circuit to design for the tesla style batteries.
  • srinivasan m August 27, 2016 at 2:36am



    James said:

    That more than 5kg of battery. I would recommend against flying something big enough to carry 5kg of battery on 6S. You'll be sloppy in the air and have poor control, if you even get of the ground on 72A.
    How much research have you done? Do you have much experience with multirotors?
    NO ,I dont have much experience. I have been assigned to make power system for such kind of a drone.
    basically 18650's weigh around 20g , so totally it will come around 2.4 kgs. Im planning to use this 410 kv rotor (multi rotor) which can possibly have a thrust for 3-5 kgs/ rotor. So using two motors makes sense. My ultimate aim is to carry pay load around 3-4 kg excluding the battery pack. If u can suggest any other power source , it will be helpful . I personally believe li-on is best suited for my requirement. 
This reply was deleted.

Activity