Wait, what if it is not in contact with any metal? With @glyphiks technique it only goes in the middle between cells. It will be in contact with the cell shrinkwrap and fish paper. It will take several days to spot weld and print my enclosure so that will be more than enough time for it to cure. I won’t even be able to see the silicone since it only goes in the gaps in the middle. Will the acetic silicone have any effect on the cell shrinkwrap or fish paper?
Its the vapors offgassing from the curing silicone that do the damage
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Ohh so it’s the vicinity of the silicone in the middle to the ends of the cells?
Vapors will fill up a whole room to some density
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I won’t use it around my cells but can I use it around my enclosure to the deck? My rubber gasket should seal off the battery from the rest of the board but could some gas get in from this?
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The silicone farts and the electronics/metals can get ill when they smell fart.
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I reckon you’d probably be ok to do that
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Please cover up ALL the nickel strips you aren’t working on. This is giving me chills.
You can use kapton tape or maybe a cloth, just make sure it’s properly in place.
Why do that, you might ask? To prevent making fireworks WHEN you accidentally push the nickel strip you’re working on, over to the wrong spot and it makes contact.
Don’t worry, most people have properly been there including me, but no need to play with fire when
you can avoid it 
Other than that, looking nicely isolated 
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Can’t stress that enough
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Thanks for the heads up, I used kapton tape to seal up the entire battery!
It’s so easy to forget the outcome of shorting out a P group.
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Just need to do it once and you won’t forget 
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Just for 100% bulletproof clarity, I mean when you’re working on the battery. Not when it’s actually finished
I’m sure that’s what you mean, I just got a bit confused with the “used”
Why not stick four together in a square, then add the other ones around it? Then all the cells are stuck to each other.
Silicone RTV is moisture-cured (reacting with the chemical that prevents curing). Sealing up the enclosure too soon could prevent curing but not because of the oxygen being used up.
Just a side note…very high humidity can actually work against you by tightly sealing up the RTV’s skin and slowing down moisture ingress into the rest of the RTV, extending the curing time. As you might expect, low humidity extends curing time too.
Give it a week to cure fully, at least, if anything is going into a sealed enclosure.
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Update, cause was p-group with some welds that popped loose 
. I’m examining everything again just to make sure this doesn’t happen elsewhere. So far the other groups are within .01 volts of each other… so I think it looks ok.
I think I’m too stupid to live without a smart bms. I’ll sleep a lot better.
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Well hey at least you found it! I love my smart BMS’s, being able to check cell levels is great
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100% this. I’ve got a weak p-group in my bike (could be a bad cell or just a bad connection, or something else), but the pack is big enough that I can just work around it and keep an eye on it with the smart BMS.
(Because I really REALLY don’t want to tear down the bike and pack, since I just got the whole thing together. Eventually I’m gonna build a bike V2 with a fresh pack, and then it won’t be an issue anymore.)
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Calling LLT wizards. I’m going to get one of these Smart Chargers coming… I am currently in 13s but I’m thinking about ordering this thing in 14s or 15s since the spintend ubox seems to be good for it. I feel like I’m wasting available enclosure space and I have lots of xtra cells.
Moron Smart BMS n00b question:
If I order in 14s or 15s knowing that I might want to add an extra P group(s)? Will it easily re-configure as a 13s?
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Yeah, the PCB works up to 15s. It requires bridging pads on the PCB but isn’t super difficult.
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