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You are completely guessing at what information DJI's software uses to determine flight time ("voltage tables"? Yeah.. I'm not buying half of that and.... voltage tables sounds like it has something to do with... voltage). What we do know is that it at least uses distance from home point and volts. I would not doubt that it uses more information but anything past that is a guess/speculation.
Using amps determines the draw on the battery but I say that this would be a very low level in determining flight time. You could be at full throttle and the amp draw would be huge. If amps were a major determination, flight time would be greatly reduced. But as soon as you went into a hover, amps would drop and the flight time would be greatly increased. That would make the percentage almost worthless.
Battery temps should lower volts more quickly. Same is true of most other things.
So I have no doubt that additional factors are used (but we don't know what they are or to what extent) but I'd say that voltage and distance from home point are the two most important factors.
I'm not saying people should ignore the percentage reading. What I'm saying is that people should also turn on and monitor the voltage reading as it can give more detailed information.
TCOPE I am not guessing any more than you are. Unfortunately you seem to be relying to a large extent on a combination of outdated technology and a flawed understanding of several key concepts.
Are you seriously suggesting that DJI might go to the trouble and expense of incorporating advanced battery management SOC’s in their products only to then not benefit from their features? That they might simply take the voltage and % remaining data from the SOC? That is a ridiculous assumption. I don’t think they could possibly be that silly. Luckily it is apparent that they aren’t. The fact that the remaining flight time depicted in GO is demonstrated to be as accurate as it is and so effective in accounting for actual flight conditions and battery health demonstrates simple voltage measurement alone is not the scheme employed.
There is no question that the difference between individual cell voltages (call balance) can be very important. I agree we should be paying attention to it. The fact remains however that monitoring overall battery voltage in flight is significantly less reliable and accurate in determining remaining capacity than observing the reported battery % and estimated remaining flight time.
Distance from home point (or specifically the estimated time to return to home) obviously is and must be a factor. The other important factor is the estimated remaining flight time determined by the battery management SOC (time until empty), voltage being only one of many factors that contribute to its estimation.
Of course voltage tables relate to voltage. Cell voltage has been used to estimate the state of charge of battery cells for a long time, well before LiION cells were available. The concept is a simple one, voltage indicates state of charge which, for a known cell capacity and cell chemistry, will allow remaining charge to be estimated. Its application is simple to implement, a “voltage table” is created by terminating the cell with a precision dummy load and measuring and plotting cell voltages during cell discharge against cell capacity minus Ah delivered. The limitations of this scheme are well known. Cell temperature, current demanded by the load and cell condition being the principal variables of greatest contribution to inaccuracy.
You say the percentage estimation of remaining capacity would be worthless if amps (current draw) “were a major determination”. I never suggested current draw was a major factor, it is one of many factors that are used by the SOC to estimate time to empty.
Temperature also is an important consideration and is also a factor used in the estimation of capacity and remaining time. I’m not sure what point you might be making with respect to your comment that temps should lower volts more quickly? LiION, like other chemistries, offers improved performance as temperature increases (the trade off being reduced life).
The various battery monitoring SOC’s employed in DJI batteries (sourced from Texas Instruments) are well known. If you are interested in understanding how they operate have a look at the white papers. The principal algorithms employed and their operation (including what parameters are measured and their importance) are referred to “Gas Gauge” and “Impedence Track”.