3.5V resting or under load?
3.2V resting or under load?
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Stop riding at 3.2v
Edit: wait, nope. I had my 10s setup in mind.
I stop riding my lipo at 42v (12s) aka 3.5v per cell.
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3.3V resting voltage is way to low for Lipos in my experience.
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What was the difference in cycle life you were seeing with 3.3V resting voltage versus what you are using now?
I didn’t really see any but was babying my packs during charging and storage. Always been curious how much of a difference that really makes but just not curious enough to spend the money and weeks to months of cycle life testing to find out. 
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Under load.
3.6-4.15 gets me 75/80% of the watt hours. I imagine 3.5-4.2 would be closer to 85/90%.
I have a theory as to why RC lipo usage doesn’t really translate to esk8 usage
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I don’t have enough data to quantify.
However everytime I ran my lipos that low I noticed bigger imbalance between cells and the voltage sag was very noticeable when drawing high currents in my big rc helis (>100A from 5000mAh packs).
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I’ve been told that 3.6V, you still have a lot more juice left in the battery that hasn’t been used. Then again would that damage the cells if I go lower. Maybe, based on what I’ve seen explained here. For my setup, I’m not planning on upgrading till later on so I do need the batteries to especially last for a long long time. That’s one of the reasons why I made a poll, to see what’s the safest cutoff voltage
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How much battery do you have left when the cutting the voltage at 3.5, well wait that’s hard cutoff, you have your soft cutoff at 3.7, isn’t that a little above?
i wacc the shit out of my packs
charge at like 4-5C here and there, at least always just above 1C, discharge to the absolute limit, sometimes multiple times a day, and they’re still kickin round no problem after at least a year of use
however i don’t skimp out on a proper charger
and NEVER skip out on balance charging
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At 3.5v probably ~5% left
The soft cutoff for me serves as sort of a low voltage alarm, lets me know that i’ve hit 3.7 and I should probably stop riding but leaves me enough range to get somewhere in a pinch. I haven’t tested how much range I get from my soft to hard cutoff but I would guess 2 or 3 miles maybe.
Lipo = cheaper, less sag but way less lifespan then Lion. Cheaper therefore only in initial cost. Hope you have factored that in to your decision making.
Not true. For esk8, Li-ions have nothing on Lipos except energy density.
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agreed
lipos well taken care of can last just as long
lipos are more “power dense”
liions are more “energy dense”
i found my liion packs have ~2x as much Wh compared to my liions for a given volume
but my lipos have >2x the output current capabilities for a given 1p set
pick and choose how you like, just be sure you understand what you’re getting into
in rerms of pricing, you can go for cheap packs, but if you get a good liion cell and a good lipo pack, the $/Wh will end up being roughly the same
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You could set the cutoff for the ESC and it’ll slow down when it reaches that cutoff voltage?
Plus it depends on the quality of the lipos. The ones I got, CNHL. From what I heard their good for the price, I’m sure anybody that rocks those can vouch for that. For the budget I had, these were the next best thing to get
cutoff_start reduces the current that the vesc will pull from the battery
cutoff_end cuts input from the battery at the set voltage
you can raise the distance from start and end to help get an indicator when you battery is getting low
So for sure the end should be 37v that’s where the board will stop completely, that’s the end, the start could maybe be close to that so it starts to slow down
37 is too high
don’t forget lipo voltage bounces back, so 3.7V under load may actually be 3.8-4.0V sitting
and lipos like to sit around 3.7V for most of heir discharge cycle, i recommend 31-32V end, that way it’l be roughly 3.7 ish at the bounceback. set the start to wherever you see fit while none of the cells dip below 3 per, long as you keep you cells balanced, wchich the bms will take care of
if you’re confused just leave the cutoff settings to be stock, vesc is more conservative
Wow, I’m still learning, people are always talking about way less cycles on lipo. I’m super careful with how I treat and charge mine (if not using for more than a few days I always leave at storage voltage). But they are just regular Turnigy so don’t know how well they will hold up against a lipo pack.