Battery VOLTAGE Reading More Important Than PERCENTAGE Reading?

[Just Mark]

Is it fair to assume that the VOLTAGE reading of batteries (in my case, a P3A) is more accurate than the PERCENTAGE reading of a battery - which I assume is supposed to reflect the CAPACITY of the battery?

Should we monitor battery voltage primarily and use the percentage reading (capacity reading, I am assuming) as a secondary guide?

Does the software monitor the VOLTAGE of a battery and then try and deduce what the remaining capacity is, since there is a ROUGH correlation between voltage and remaining capacity??? I know that a lot of battery monitors work this way since it is easier to monitor voltage accurately than it is to measure capacity.

Or has DJI actually developed an accurate way to monitor remaining CAPACITY?

And if I am correct and we really should be monitoring VOLTAGE first and capacity second (again, assuming that the PERCENTAGE is referring to the estimated remaining capacity of the batteries), at what voltage level (in a stable hover) should we start landing?

Thanks in advance.

 

[msinger]

Check out this thread.

 

[N017RW]

Been using LiPos since '06.
Cell/pack voltage is the only (reliable) way to monitor SOC (state of charge).

Too much reliance on s/w to trust any other metric.

However YOU must assess the rate of discharge to determine (remaining) run time until you hit the critical 3.3v/cell and TERMINAL 3.0v/cell levels.

 

[sar104]

Been using LiPos since '06.
Cell/pack voltage is the only (reliable) way to monitor SOC (state of charge).

Too much reliance on s/w to trust any other metric.

However YOU must assess the rate of discharge to determine (remaining) run time until you hit the critical 3.3v/cell and TERMINAL 3.0v/cell levels.

And incidents like this one demonstrate that quite clearly:

Lost power and crashed

 

[Just Mark]

And incidents like this one demonstrate that quite clearly:

Lost power and crashed

Thank you for the link and the info.

How common is it that the voltage measurement, the percentage measurement (I am assuming this is and ESTIMATE of remaining capacity in mAH), and the voltage percentage are so off with one another?

And if we assume that percentage (I am calling it "estimated remaining capacity" until someone corrects me on this) and voltage percentage are subject to significant error, how much faith can we have in the actual voltage readings? Are the actual real-time voltage figures likely to be accurate?

 

[sar104]

Thank you for the link and the info.

How common is it that the voltage measurement, the percentage measurement (I am assuming this is and ESTIMATE of remaining capacity in mAH), and the voltage percentage are so off with one another?

And if we assume that percentage (I am calling it "estimated remaining capacity" until someone corrects me on this) and voltage percentage are subject to significant error, how much faith can we have in the actual voltage readings? Are the actual real-time voltage figures likely to be accurate?

I don't know how common it is. That's the first data I've seen that demonstrates it so clearly but there have been plenty of reports that implicate it as a problem, and both @Meta4 and @msinger have documented the issue many times.

Percentage values are inferred by the software, whereas battery voltage is a simple direct measurement that should be completely reliable.

 

[Just Mark]

Percentage values are inferred by the software, whereas battery voltage is a simple direct measurement that should be completely reliable.

Thank you. This is what I wanted to hear. I will feel more comfortable flying now knowing this, and will continue to monitor voltage and pay less heed to percentage.