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I'm trying to figure out if there is a way to use a Lithium accumulator to power a drone. Because of the maximum recommended continuous current of the battery, which is too low, I can't drive my motors and electronics.

Is there a way to hack this into working using a supercapacitor or an alternative like hooking up many lower capacity accumulators ?

I'm interested, as you have guessed, in low mass and high capacity.

The details of the accumulator are :

  • Nominal capacity : 19Ah
  • Voltage : 3.6V
  • Max. recommended continuous current : 230mA
  • Max. pulse current capability : 400mA
  • Weight : 98g
  • Volume : 51cm3

Link to the datasheet (page 6)

PS : I'm working on this. My version will incorporate a pinhole CMOS video camera and a wireless transmitter.

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  • \$\begingroup\$ Did you mean to have "mAh" as your unit of current? \$\endgroup\$ Jan 5, 2014 at 22:19
  • \$\begingroup\$ Also, keep in mind that thionyl cells are not rechargeable. \$\endgroup\$ Jan 5, 2014 at 22:22
  • \$\begingroup\$ I was not aware of the fact that thionyl cells are not rechargeable, thank you for that and I've corrected the unit of measure, thanks. \$\endgroup\$
    – StefanS
    Jan 5, 2014 at 22:27
  • \$\begingroup\$ That copter's not going to be able to lift that cell in the first place, regardless of discharge rate. \$\endgroup\$
    – user16324
    Jan 5, 2014 at 22:43
  • \$\begingroup\$ True, but it's not for that particular one, I'm using different motors, different components altogether, and this is another discussion, let's keep it on topic. \$\endgroup\$
    – StefanS
    Jan 5, 2014 at 22:56

1 Answer 1

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A bunch of capacitors aren't going to fix a sustained discharge rate problem. Capacitors can provide high peak currents for a short time, but they store relatively little energy compared to a battery, so anything sustained must come from the battery.

The basic problem is that this battery is inappropriate for this application. Lithium polymer batteries have good energy density and can provide more maximum current for the same size or capacity.

Paralleling multiple batteries does give you higher discharge rate for the combined battery. However, the real problem here is the that maximum power output per weight is too low, and using multiple batteries, regarless of how they are connected, can't change that.

Put another way, this battery can only put out 830 mW. That's simply too little to lift its own weight. Batteries for copters are usually depleted in 5-20 minutes, meaning that they put out Amps 3-12 times their Amp-hour rating. It would take 80 hours to deplete your battery at maximum current. This battery is meant for long term low drain. A copter requires exactly the opposite.

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  • \$\begingroup\$ Thank you ! In the end, sometimes you just can't hack it. \$\endgroup\$
    – StefanS
    Jan 5, 2014 at 23:50

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