SP140 - Battery low power cut off mechanism & thresold

I am not so worried about the cycles but rather about capacity, personally. I rather be up in the air longer than more often. While you have around 80% of capacity left after 500 cycles at ~10A discharge rate per cell you may have a lot less capacity when you go with 30A per cell. If I read the chart correctly you are at 80% capcity after 200 cycles when discharging at 20A. And we dont know where we will be at at 30A per cell.
Both HVC/LVC(high voltage cutoff/low voltage cutoff) together with discharge rate has impact on Capacity loss. Thats also why a 4kWh battery will most probably live longer than a 2kWh

Oh and you are correct jsneeb at 3,3V(80V) per cell there is basically nothing left in the tank. Could be a sweet spot to tune in controller for a power limit(?). Will take note of that.

Definitely, something like a 50% power limit at 80V would be a good start point. However, also consider that at lower voltage your max power is already reduced. Then maybe consider going up to 75% power limit, or tweak the voltage down a bit more to accomodate the voltage sag. I find that around 75-76V under cruise power, my OCV is 80V. At 80V OCV I start looking to land. That gives me 2 or 3 go arounds of the field if something isnt right.

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only as a hint . the data sheets from the battery manufacturers always refer to a cell in a cooled environment at around 20 degrees celsius. as soon as itā€™s a battery pack in a housing without cooling, the world is completely different. the number of cycles drops dramatically as soon as you very often get to 3 V per cell under load. there are also many inventors who have tested hundreds of cycles under different conditions. my opinion is that if you stress the molicell too much, a maximum of 150 to 200 cycles are possible or a running time of 2-3 years, with a good 20% of them no longer being usable. Under ā€œstressā€ I see a continuous discharge of more than 15 amps per cell. Ideally, less than 10 amps are needed and a maximum of 15 amps for a short period of less than 30 seconds. Iā€™ve been flying molicell myself since 2018/19.

Is it 300A the controller is drawing as a max value?

Has anyone played with these settings yet? This is one of my big safety concerns with this setup and Iā€™d love to know it any of these options work and how well.

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I configured these settings for now. But have yet to try them out.

Nice. Can you update us after you test it? Thanks!

In the APD configurator, does anyone know what ā€œgradual shutdownā€ does and how the ā€œauto voltage limitā€ chooses that limit?

APD told me that gradual is actually the same as Hard right now.
Auto voltage limit maybe work together with Cpacity limit but I am not sure.

Have you tried this 75% @ 80V setting yet? I tried 75% @ 79V and also 50% @ 79V and both didnā€™t seem to do anything. Sure the max power at 79V was less than on a full battery, but it definitely wasnā€™t a 50% reduction in anything once I dropped down to 79V. I switched from 75% to 50% because I thought that maybe it was happening and I just didnā€™t notice it, but Iā€™m pretty sure Iā€™d be able to tell the difference between normal output reduction as the battery drains vs a 50% limiter, but maybe Iā€™m misunderstanding how itā€™s supposed to workā€¦

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