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Operation Hours for LiPo Battery

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killer_fighting

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I am using a LiPo battery and the specs is below:
Capacity: 4.4 Ah
Discharge Rate: 60 C
Voltage: 22.2 V

I am using a LiPo battery to power up two motors and the current required is about 14 (A).

How can I calculate the operation hours for my battery?
 
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I'm not sure what the spec is saying. Is the quoted Discharge Rate the maximum allowable rate, or is it the rate for which the battery will have a guaranteed 4.4Ah capacity?
 
According to the specs, the battery will be fully drained after 18 minutes.
(4.4Ah / 14A) = 0.31 h

As you discharge the battery, the voltage will drop. Over discharging kills your battery very fast.

For safety you should not never discharge a LiPo pack down past 80% (3.75V per cell) of it's capacity. So if you take that into account you have:
0.31 h * 0.8 = 15 minutes
 
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According to the specs, the battery will be fully drained after 18 minutes.
(4.4Ah / 14A) = 0.31 h
Maybe.
We don't know if the motor is working hard, working a little or idling.
My electric RC airplane uses 50mA when cruising or 4A when climbing vertically at full power. The duration of a battery discharge varies a lot depending on how hard it works.

For safety you should not never discharge a LiPo pack down past 80% (3.75V per cell) of it's capacity. So if you take that into account you have:
0.31 h * 0.8 = 15 minutes
No.
The battery is safe to discharge each cell down to 3.2V. The cells are pretty-well matched.
Each cell is 4.20V when fully charged.
The 22.2V battery has six 3.7V cells in series (for a total of 22.2V) so each cell is 3.7V when half-discharged.
 
Maybe.
We don't know if the motor is working hard, working a little or idling.
My electric RC airplane uses 50mA when cruising or 4A when climbing vertically at full power. The duration of a battery discharge varies a lot depending on how hard it works.

Yes, of course. I just wanted to give the "naive" answer to the original question, so the OP has a chance to understand the math.

No.
The battery is safe to discharge each cell down to 3.2V. The cells are pretty-well matched.
Each cell is 4.20V when fully charged.
The 22.2V battery has six 3.7V cells in series (for a total of 22.2V) so each cell is 3.7V when half-discharged.

I checked the numbers from this page: https://www.rchelicopterfun.com/rc-lipo-batteries.html
Is the information there wrong, or did I misread something?
 
I am using a LiPo battery and the specs is below:
Capacity: 4.4 Ah
Discharge Rate: 60 C
Voltage: 22.2 V

I am using a LiPo battery to power up two motors and the current required is about 14 (A).

How can I calculate the operation hours for my battery?
If you are discharging at 14A, that's about 3X the "C" rate so your battery will likely deliver maybe 80% of it's rated C rate (rough guess, the manufacturer should have a graph for this). The specified C rate is usually for a discharge rate of about c/10. At higher discharge rates, there are a lot more internal losses so the C rate is much less. So assume it's now a 3.5A-hr battery. At 14A, the battery will last about 3.5/14 hours or maybe 15 minutes.


The curve below shows how battery capacity drops at higher currents.
 
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