Altitude overshoot on ascent & descent, tuning help please

@Leonardthall yes send whatever build you want my way. I need to fix my txmodv2 before I can fly but I should be able to get to it mid-week. What do you mean by “series climb and descent” – on flat ground ascend straight up, wait at the apex for a bit, then descend straight down, wait at the bottom, repeat a few times?

Where do you see 24.3 V for the starting voltage of the battery? EDIT: I see you are looking at the estimated resting voltage a few seconds in—I take it that’s the best voltage to go off of.

Note I’m using Li-Ion not Lipo, 6S2P 18650 cells for 6000mAh rating

Wow I just took a 30 minute interlude to dig deeper into the Li-Ion research than I had previously, and messed about with my charger. I’m using the GEPRC brand VTC6 battery. This wonderful report shows some discharge curves for that SONY VTC6 18650 cell.

They are supposed to be charged at 4.2 V to a 100-125 mA cutoff. Then soon after coming off the charger they are supposed to have a resting voltage of 4.10–4.19 V? Which would be 24.60–25.14 V? (That number wasn’t as easy to find–it’s not in the datasheet and different sources on the web disagree slightly.)

I have been using my charger on the “Li-Ion” mode. Turns out that charges them to 4.1 V rather than 4.2 V. I am annoyed that I did not catch that discrepancy until now, but better late then never. I just upped the charging condition to 4.2 V and got another 638 mAh into it. @Leonardthall your inquiries just increased my battery capacity, no new purchases needed!

Also I just checked and fixed the battery cal; it was off by 0.3 V which is something but not huge. Between undercharging the battery, and that 0.3 V, maybe it accounts for the discrepancy. The issue with the voltage I see on the screen of the taranis being different than what the FC knows is a separate thing and still a problem; hopefully I can resolve that on my separate txmod question thread. Whatever the voltage really is, it does me no good if the telemetry shows me old/wrong numbers.

I know my current cal is real close because the reported consumption is within a few percent of the amount that goes back in.

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