Hi. What do you guys use to lay the batterypack on to in the enclosure? Like foam, or rubber thing?
Thinking about vibrations etc.
Many people add a layer of foam on top and bottom of their battery that sandwiches it between their deck as it will dampen vibrations and protect it. (at least this is what I’ve done)
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Is there some material of foam/rubber i should stay away from for this purpose?
Unsure, I just used whatever I found. I wouldn’t think there is, but someone else should give you a definite answer
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Closed cell foam would be the preference as opposed to open. It will do a better job.
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got some pure nickel foil if anyone needs it
I realize I am about 6 hours too late at this point, but just to reiterate for anyone reading this thread in the future:
My whole suggestion for how to fix your pack earlier was focused on not putting anymore heat into the cells. That’s why I suggested soldering up your series connections to the nickel and THEN welding the nickel on. That way, none of the heat from your soldering can be transferred to your cells.
Anyway, like I said I’m just putting this info here for others to hopefully learn from.
Shua, I am glad that you are determined enough to make a safe pack that you would go the extra mile to address your earlier mistakes. I hope that this pack is safer now than when you started, and I hope you have learned a thing or two that will make your next pack even safer.
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Yeah I had an old pack that I wanted to salvage cells from for a portable charger, I didn’t feel safe using cells with rounded negative ends. I have a brick of like 40 brand new M35A that are pretty much useless. I took like 20 welds off and gave up after an hour and scary prying.
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Neoprene with adhesive is nice to work with.
https://www.amazon.com/Sponge-Neoprene-Adhesive-Thick-Wide/dp/B001G8E114
It’s nice to have different thicknesses. 1/8" and 1/16" is also useful.
And this is not gonna be a thermal problem for the esc, or batteries? Make the esc hotter or something.
Also, the esc will be ok inside the enclosure, without cutouts and stuff like that?
The ESCs we use pretty much all have good thermal protections built in, that decrease power output as they get close to the maximum allowable temperature. They won’t just cut off suddenly from heat, but rather simply limit the maximum power until they cool down.
If you are consistently getting thermal throttling though, you can either mount the ESC(s) externally, or mount some external heatsinks or something to get the heat out.
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yep im going to do that
first solder and then weld.
i wont put anymore heat in and the sanding will be done today
didnt do last night as was getting late and i didnt need any sparks
thanks for the help
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Happy to hear nothing blew up 
Like @BenjaminF said, for god sake don’t put more heat into that battery! 
How exactly are you planning to do this connection? I don’t really think we’re on the same boat…
When sanding, make sure you cover up ANYTHING that’s not what you’re sanding. You don’t want that dust inside your battery… I’m sure you already know this, but make sure you clean the ends of the cells with some alcohol once you’re finished sanding 
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Hello guys! I have a problem, maybe professionals have idea.
I bought a 12s6p 30q battery.
There are burned points at the end of my battery, what almost new (used total 40kms). I made a diy board and some happenings were before i realised the burnings…
One time the charge port was bad, it is also burned (shortcircuit)
Then one of my vesc dead (also shortcircuit).
The bms was discharged that time, it was 40a.
The cells still good, but i have to sure i fixed the problems, i dont want to burn it.
I changed bms to bypassed, but i will use fuses.
I made stronger the end of the battery, because the wire started to melt down.
So do you think it caused any other parts shortcircuit, or the battery construction is weak and can’t hande 40 amps. (I’d like to use it with 120a already now with bypassed bms).
What do you recommend, and how can i test it?
Thank you very much for your helps!!
10a81b3951d6780a27d13a0cf599d260|375x500
The way how that looks is as if something got in and caused it to short circuit. But that nickel looks weak. Make sure not to add a fuse to the discharge wires… only for the charge port. And lastly, where did you purchase that pack? Usually that’s a sign of “bad work” doing. But you can probe your discharge wire with a multimeter and measure the voltage and see if it still gives you the 12s voltage.
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Thank you for your answer. The short circuit was fixed, i changed the dc port, and the vesc came with factory error, replaced it too…
Voltage is 43 volts now, but it is on 10%. We mesaured all series, it balanced…
I bought it from china, but not was the cheapest.
My other battery from there works perfect, but it is only 10s2p.
Vesc company recommended me to put fuse to discharge wire, one 120a fuse per vesc (240a total).
Is it possible, the battery construction can’t handle 20-30a and then burned? I think i didn’t drown more than when i tested…
No, It looks as if the burnt was from the nickel. But I do not recommend adding the fuse. If that broke during your ride, let’s just say this would be our final conversation. The battery construction looks iffy, however, if you can charge it and then do a quick test with a different vesc-based esc, you can check whether or not it can do 120A. Although, that only does 90 amps max.
I think a second opinion would be helpful here as well.
Those pieces of nickel may not be enough for the load you’ve got on them there.
What size is it? How much current was going through it?
That battery is built poorly. They only used one thin nickel strip for the series connctions. At 20-30A that tiny strip just can’t handle the current and get’s super hot. That’s probably why it melted the heatshrink.
The best option would be to have a decent battery builder rebuild that pack.
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the plan is to take a 25mm nickel strip (largest i have atm) and fold it over the edge of the p group then solder to it.
the other option is to solder first and then weld
edit: also for alcohol is there something else i can use (dont have any atm) maybe acetone or something similar