i keep syain the same thing,
3.1-3.2 under load will lead to the pack recivering to 3.6-3.7 once itms sat around for a couple minutes, it’s completely fine
It would be 3.6v under load so fairly safe.
Wouldn’t having it that low affect the batteries since it’s in the danger voltage where you don’t want to be
No. You have no idea whether it will bounce back or not. If someone is just cruising at 12mph and using minimal amps, when the voltage hit 3.1v, your batteries are fucked.
If you are racing balls to the wall, then sure. Otherwise, its too risky.
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Have 37.10v as soft cutoff and 36v hard cutoff?
Yep. just keep it round number. 37v soft, 36v hard cutoff. Your batteries will just settle to around 3.7v when you finish riding.
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the minimum safe voltage for lipos is 3.0V per cell, so whether or not it’s 3.1 or 3.7 at the end, it’s still safe for them
if as you said, i were running balls to the walls, i could be in danger as there would be a chance the cells will dip below 3.0V
but having the hard cutoff at 3.1-3.2 would mitigate that
Would that show it on the LTT BMS where it’ll stay when the batteries reach the hard off?
The BMS will show you the voltage for each cell so yes. The vesc will stop the board at 36v and then you can look at the bms app to see what your voltages are for each cell.
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And it should be around 3.7v when it’s finished
But we have to factor in lifespan. Constantly going under 3.5/3.6v is what reduces lipo lifespan and then people come and complain that their batteries are puffed in 3 months. Take your li-ions to 2v per cell constantly and see how long they last.
Most here recommend a cut off of 3v per cell for li-ions when they are specced for 2.5v cut off. Why wouldn’t you do the same courtesy for lipos and stay above 3.5/3.6v?
Yes.
Alright appreciate it. You mind explaining how I would wire the balance wires and everything, I sent a photo on your thread
Do you have everything ready to solder?
i happily take my lipos to 3.0-3.3V under load every time on my board
300+ charge cycles and at least a year later they’ve yet to puff beyond a mm past they’re factory state
Yep, I just need my 7.5A 58V fuse for the charge port and that’s all
Ok. I will reply to you there.
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Thats great to know tbh. I wouldn’t recommend for newbies but you sound like you know what you are doing.
If I go below 3.5v the battery is lower than 0% when placed on charger.
Not sure how everyone else math is working for them but if a Lipo Charger states my battery is at 0% when at 3.5v per cell. I assume the Lipo Charger is correct or at least dam close.
Anything under 3.5 has made my battery warmer than normal, caused unbalanced cells that take longer to charge and balance, and has made batteries swell. I can go ride right now on a new pack. Set high cut offs, hit them cut offs and feel my pack and read my cell levels all being good. Then in that same ride I can open the app, change cutoff values ride less than a mile more and have swelling and heat from the pack. I do not suggest doing this for any reason unless you want to throw away your pack when done.
I can prove this swelling/heat if settings such as 3.0v per cell are set for your Cutoff End.
Just give the cash for the pack, because Im not testing it on mine. I know what it does from experience.
I suggest 3.6 or above.
Not all cells drain even if ever, this 3.6 leaves min head room for the unbalancing that will happen
naturally and at lower battery percents. The idea is to not hit 0%. You can learn what 0$ is but you really dont want to hit that. It will take longer to charge ect etc. Now if you dont care about your time, your pack, your wallet, set it lower than 3.6 but never below 3.5 since that is DEAD.
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