Make sure the BMS lead wires are all good, sometimes the BMS is fine, but some wire is not. Well, the BMS is dead, often, too.
Yeah true, I just saw 2 and 2 and assumed 2 series 2 parallel.
It stems from me somehow coming to the conclusion I had 10s2p which is not correct also. Haha, still heaps to learn thank god for this thread!
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There are no dumb questions, just answers that make you feel dumb afterwards. 
Better to ask, than to continue blindly.
Think of the P part of your pack as a multiplicative factor. If you have 10s1p, you have 10 cells. If you have 10s4p, you have 40 cells. Since you’ve got five 2s1p lipos, and since math is commutative, 5x(2x1) = 10x1 as in 10s1p.
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Thanks heaps man, I am confident you’ve saved me and many others from broken electronics or burnt houses!
And dumb answers after a few beers 
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My 10s4p pack only charges up to 94%. There’s a S group that doesn’t seem to be charging and is stuck at 3.50v while the remaining 9 S groups are fine at 4.10 each. I don’t think the cells in that particular S group are bad since I’m able to charge up that S group individually. I’ve already checked the wiring and connections. It is a bad BMS? Any ideas?
Depends. What battery? What esc? Did you get the HW or YingLi version? New price 429$
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Standard battery life Hong 6.5li-ying 6.5
I’m having issues with my flipsky 4.12 vesc. I cant update firmware or bootloader using the VESC tool.
When I connect the vesc I get this
and when I try to updated the firmware I this
Any help would be greatly appreciated 
thank you.
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You need to download the newest version of VESC Tool:
https://vesc-project.com/vesc_tool
Alternatively, you can try Ackmaniac version:
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I’m so goddamn proud of you
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Ugh, good enough
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Does the stuck group change at all during charge/discharge? If not, then it must be a bad series connection - basically that group got skipped when you were doing your series connections.
You need a newer version of vesc tool, looks like.
The stuck group discharged fine. The pack started out at 100% when I first built it. Then I rode the board down to 50% but then it only charges back up to 94%. Also, my series connection are spot welded of .2mm nickel strips and the groups are stuck together good.
Hi mate I downloaded the vesc too from that link is there way to check the vesc tool version?
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