I’m going to ditch this connector. My question is What is this and do I need to keep it? I plan to plug directly into the charge port.
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Looks like a shunt resistor. You’ll need it to see current measurements
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DC IN is where I’d connect the charger coming from the wall and the LOAD would be plugged into the charge port correct?
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Yeah that sounds right
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cool, thx
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Any ideas how to test it out under a high load to see if it heats up in certain areas? I don’t want any problems to come up while riding it
Connect to an array of incandescent lightbulbs?
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Can’t see inside of the wrap/kapton but the balance routing looks good. From what I can see, looks like a solid first effort. Assuming this guy is an antispark?
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looks more like a fuse to me.
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Outside looks good, do you have pictures of the build process? Otherwise it’s hard to say anything.
A large coil of nichrome wire in a bucket of water. Calculate the resistance to achieve the maximum rated current.
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Hi All. Sorry for interrupting this thread. Hope here it is right place for my question. Iam just received Nkon batteries with clear wrap. But what surprised me is that this cells have on positive pol just fish paper ring below clear wrap. I saw till now plastic one.I need build 3 packs for top mount on mountain boards. So if I will stick on it next fish paper ring, it will be ok? Slightly doubt , how safe it is .Thanx all for any comments.
Those FETs say they’ll do 70A continuous each, with case temp at 100C. Maybe I’m missing something thermally (that the aluminium block heat soaks really quickly and then can’t dissipate it) but from the datasheets it seems fine for a lot more than 20A? I can’t quite read the part numbers on all of the fets to confirm if they’re all the same and ganged up in parallel, maybe they’re laid out in a way that severely limits it like one series FET needing to take the full battery current, but still it seems reasonable
@ApproachCautiously I think you should put down strips of fish paper between the overlapping balance wires, that’s the standard method like these from Al. The little rafts keep them safe from eachother
Quick Google gives a range of operating temps for hot glue, the lowest range still seeming to be safe for ~80C. Hopefully the outside of your cells stay within that 
. And yeah I use electronics safe silicone from RS or dowsil, I think my pack with it is only 12-18 months old but so far it has held up nicely, no drying out
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put it in the books, i’ll visit ya again within the next 4 years!
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That would require me to have fish paper which I did not have when fixing it. 
I’m not planning to sell the pack any time soon, and if I ever do I’ll make sure the use of hot glue is known. If it could survive in that original state for 5 years I’m sure it’ll be fine for longer with the hot glue
If I was rebuilding it fully or just building a new pack I wouldn’t let it look like that to begin with. I’d do it the right way to begin with. Although the pic of it to start with 100% belongs in that other thread as a bad example. 
How they didn’t end up shorted to the battery terminals when shoved between them is a mystery.
Most of the silicone available at the hardware store already is electronic safe. Personally, I picked up some that was clear but that was to make it easier to remove if I wanted to fully enclose anything in it, but the stuff I have is too flexible for that use anyway. Luckily it works super well for creating more of a seal on my enclosure as even after it is cured it is slightly tacky. I didn’t want to waste a full tube of my gasket making silicone when I do have future plans that would require removing the gasket.
Not here it’s not anyway, I really had to go out of my way to find neutral cure stuff. The vast majority is acetoxy cure
As far as I’m aware I bought a neutral version although of course it isn’t listed on the product itself. It very much smells like one and the tube lists the vapor as flammable which is on par for neutral cure.
Then again the tube does list itself as being tack free in 30 minutes which isn’t even accurate, so I really shouldn’t be surprised it doesn’t list the cure type. the stickiness it keeps works well for my uses at least.
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