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.
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 itās 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 āstressā 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. Iāve been flying molicell myself since 2018/19.
Has anyone played with these settings yet? This is one of my big safety concerns with this setup and Iād love to know it any of these options work and how well.
Have you tried this 75% @ 80V setting yet? I tried 75% @ 79V and also 50% @ 79V and both didnāt seem to do anything. Sure the max power at 79V was less than on a full battery, but it definitely wasnāt 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 didnāt notice it, but Iām pretty sure Iād be able to tell the difference between normal output reduction as the battery drains vs a 50% limiter, but maybe Iām misunderstanding how itās supposed to workā¦
