@Red_souls FYI
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I got 2
4500mAh 30C 5s Lipo batteries.
The charge is 4.2 and I’m thinking my cutoff should be 3.6, anyone agree?
@Red_souls It would need to be 36v in the esc settings. There’s one setting for cutoff start (esc limits power so you’ll feel your board slow down but can still head home) & cutoff end (power cuts off).
I have my 12s at 44.4 start (3.7v per cell) & 42 end (3.5v). I also plug in two voltage alarms as I’m paranoid about cell variance.
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A 3.6 cutoff is too low IMHO
You might gain like ten meters extra range and seriously increase the risk of damage to your packs
My bad I put 3.6 instead of 36v, would that be good?
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36v would be the cutoff, hard or soft? Also do you run a BMS on your setup, it can track your battery levels wirelessly through Bluetooth, not sure if the BMS can stop your battery from going low. Gotta ask around since I got a Bluetooth BMS, I also think it tracks the charging, then again I could be wrong on this
It would appear I explicitly suggested to NOT use a 36V cutoff.
But you can do whatever you want, it’s your stuff.
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I’m trying to get the best usage out of the battery. Without it having issues, I thought 36v is the sweet spot for lipos on a chart I saw.
Also you should set your cutoffs slightly higher than the actual bottom you are targeting, because the individual cells can be slightly unbalanced which would mean one or more could be lower than the others in a 10S or multi-series configuration. On a 1S pack, you could go lower more safely.
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Ok ok, my fault. I was told by people that 36 was good but I guess some charts aren’t accurate, so aim up for 37, what happens if one of the batteries is more balanced higher then the other? Would they need to be completely in sync or one decimal off is ok
0.1V off can start causing damage if you run the pack completely empty.
Running packs completely empty is rarely achieved in my experience, because of the desire to not kickpush back home. Range Anxiety seems to always win and you force yourself to go back home before you have no range left.
You should still use a BMS (or another way like a hobby lipo charger) and keep your pack balanced as evenly as possible. An unbalanced pack is a big problem, and even bigger problem if it’s a lipo pack.
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Could a Bluetooth BMS (which I got) in a way limit the batteries from going below the desired cutoff even tho you configured it in the software? also with connecting the batteries in series and charging them with a DC power plug (I’ll be charging the lipos through the BMS). could or can’t stop the charge or read that the batteries are both 100% and not unbalanced even a 0.1v off, haven’t found anything like that in a thread so I was just wondering
Sure, if you fancy loosing all brakes and throttle with no warning. Don’t use the BMS for this, use the ESC battery cutoff settings.
Yes, and I highly recommend that.
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Ok, the ESC cutoff won’t go below the number that’s set? Yea that was the plan to use the BMS to charge the lipos. Would I need to check the percentage and unplug it right away when it’s fully charged or the BMS would do that on its own and stop the charge when it’s completed
It won’t allow throttle below the end cutoff, but will still allow braking (which charges the battery anyway) and it will still consume a tiny amount of power idling the ESC. You should not leave it turned on for an extended time after it’s drained. But definitely for sure leave it on if you are riding the vehicle.
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Turn it off when the battery is near being drained but leave it on for let’s say there’s a little hill and I can use that as an advantage to charge the battery a bit so I can make it home
Don’t ride the vehicle with it turned off.
Yea I didn’t mean with having it off as I’m riding, I meant when the battery is almost drained and there’s no possible way for me to ride it if the roads are flat, I turn off the board and just walk till I can find a hill or I just make it home to charge it
Yes if the battery is drained I would not idle it while you’re not riding it. It doesn’t really use that much power to idle an ESC or two but it does use a small amount. Running it for less than an hour or so I would not worry about unless you ran any of the cells under 3.6V
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I’ve kick-pushed broken or dead electric skateboards home for miles before. It goes like this:
“I’m going to call a Lyft, but might as well push to that next hill first to reduce the price”
“Well I’m here, not too tired yet, I can easily make it to the next hill, will be a little cheaper”
“At the next hill, not too tired yet, I can make it to the next hill, will be a little cheaper”
…
“Well now I’m almost home, might as well just push the rest of the way and not summon a Lyft”
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