Base on Levo SL that I have demoed, 480w would yield about 25+ miles 3000 ft elev. this my usual ride.
Most ebike battery spec for approx 500 cycles.
You mean 480Wh I’m assuming. I’m not exactly sure what voltage level 48V motors are meant for, but I’ll assume 12s, which will be a bit above that. I don’t think any cell will give you that much capacity to make a 12s2p work, so you’ll have to go with a 12s3p with 21700 cells, or a 12s4p with 18650 cells. At 3p and a 15A load, that’ll be 5A per cell, which most battery cells can easily provide. So you can either go with whatever is cheapest, or if you want max range, then something like a samsung 50S or Vapcell G50 will be best.
You can take a look at these charts to see what capacity you can expect form different cells at that power level:
(There might be a language barrier here though. If you actually meant that your motor is 480W, then that means nothing. What’s important is how much power you draw per mile, so that you can figure out what total battery capacity you require. Then, based on the total capacity and the 15A you expect to draw, pick a cell that is either cheapest / provides the most capacity at that current level)
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Sorry my typo, it’s 480Wh. Levo SL ebike has 320whr inside the tube plus an extended 160whr piggy on when needed.
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Thank you much for the info! It’s a big help.
Also, check with this chart for sizing your wires, if you’re doing that yourself
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Im also looking for “how to choose bms for something like 13s2p/3p, 48V … etc”
What ESC are you planning? 13S removes probably most options which max out at 12S
13S is very likely, not sure about ESC yet.
Hi all
Im going to start building a 12s6p battery and got 80 reclaimed 30T cells from NKON
I measured them and they are:
60 cells at 3,56V
16 cells at 3,44V
and 4 cells are 0-2,7V (going to use those only for welding tests).
How do I go about constructing the P groups? Do I spread the 16 cells across all P groups or it doesn’t really matter and the BMS will sort it out?
My understanding is that it’s an acceptable difference and it won’t make any difference.
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I would use one of the lower voltage cells in each group personally. Toss the other 4 or put them in a vape or some shit.
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We don’t know anything about the lower voltage group of cells and why they are that way. If it’s due to slightly faster self-discharge (takes at least a week or two to test for this) then divide them up amongst the p-groups. If it’s just a different batch of cells then it doesn’t matter where you use them as we have no performance or cell-matching info for any of the cells.
The below-2.5V cells you can dispose of (recycle) or use for welding practice (leave them discharged).
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Also make sure to get a refund for the dead cells from nkon.
I’d say spread them out, one per P-group, and charge them up to match the others so you don’t get any current transfer when connecting them.
You have exactly enough cells to evenly split everything: 5 “good” cells and 1 “suspect” cell in each of the 12 P-groups, for a total of 72, with two suspect cells and four bad cells left over to practice on.
@Battery_Mooch have you had a chance to get your hands on the LG M50LT? Nkon rates those at 14a, would be interested in what the actual ratings are. LG INR21700-M50LT 4890mAh - 14.4A - 21700 & 20700 - Li-ion - Rechargeable batteries | NKON
Might be a good option for high p packs.
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If your are ever not sure if a pack is charged and you don’t have a voltmeter.
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I haven’t.
I’d be happy to take the time to test them though if two were sent to me here in NYC.
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Packs would be verrry unhappy.
Just a side note…I believe that only works for alkaline cells, not Li-Ion. For anyone considering testing this I would recommend not dropping Li-Ion cells due to their sensitivity to shock/vibration and the very high levels of energy they contain (compared to alkaline cells).
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I hear they beat out TNT in terms of energy density but wiki says otherwise.
Don’t worry, I wouldn’t drop test most items on this table.
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Just finished up this battery for @Boardnamics Flux build! If you’re going to Esk8con, catch him gettin the miles on this 12s8p P42a.
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