Thank you guys. Really appreciate all the info seeing a thread with 1097 replies about building, I nearly fell out of my chair.
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Another great area for anything you’re totally unsure about is here:
Is there any difference between fusing the positive and the negative?
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Thanks for the advice 
- I’m gonna change it to a sand filled one
(I liked the clean look of the glass fuse) - there is pretty much nothing I can do about that
- wires can bend easily right behind the chargeport
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Not really, just make sure there is a fuse c:
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If you, like me, don’t want to weld packs and prefer modular packs, there is a much better way: NESE. They are available for 18650 and 21700 cells.
I have them in two of my boards and have put 1200km on one and more than 400km on the other.
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charge cycles? 
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edited to reflect that i meant km
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Hey guys, I’m starting to order parts for my battery build, but does anyone know if ru.nkon site is down? Shipping quotes aren’t available and I can’t order any 30q
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Your timing is unfortunate.
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damn, that was the only site what sold $2.74/30q cell for the US. All the other sites sell them around $4.75/cell for 30q. 
guess I’m not building packs anymore
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I actually read somewhere it’s not. You are supposed to place the fuse between the main negative on you battery and B- on the bms. The fuse should then be placed as close as possible to B-.
@taz is the man I believe that said that.
The way it’s wired now, will only protect the charger from toasting the BMS but by doing it the other way, you’ll be protecting the battery. I have one each place.
I’m not completely sure if that’s how it actually is, but just what I think I remember. Please don’t hang me up on it but correct me 
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Yes, I build batteries, on my thread the pricing is explained, if you need more info just send me a message
I’m interested in that system I’ve never built a battery before i figure this will help me learn.
Click on those orange links. You’ll know what to do.
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This is for my mountainboard
Samsung 30q 12s8p
And this is for my m365
Lghg2 10s4p
Should give me a range around 25km
Everything is glued togeather with silicone
Currently I’m using the sunkko 737+ And it feels like its just not handling the load
Also I ordered the Arduino spotwelder and a huge dry cell car battery and a charger so I’m set for some more battery building
I have problem with one of bestech D140 12S. Bms was new, still in original wrap. I have connected balance wires and main negative wire from battery. Voltage on every balance wire is right and they are connected in right order (checked 3 times). Every cell is from same 100pcs battery box, every group at 3.44V. Voltage on bms input (B-) is 0.4V higher than output (P-). Bms is warm/hot on part with ‘101’ plates. I am scared to finish battery because bms should not be hot just laying on battery. After one hour of bms just sitting connected and being warm, it drained two groups to 3.40V. Bestech answered to my mail and said that it is normal that bms is warm when balancing (??? balancing what exactly?) I am scared that bms is faulty and will try to kill two groups. That happened before with d596 and I am not sure if I want to risk it again. Everything is disconnected right now. Should I let bms connected to battery for another 10 hours or so and check voltages every hour, maybe it will start balancing after some time? Any ideas?
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Isnt the balancing wires suppose to be the last thing you connect to the bms? Correct me if im wrong, something ive read somewhere?
this is charge only bms, so It doesn’t “see” if there is charging port installed or not. so yeah, balance wires were installed last.
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