The battery builders club

90+ amps, easily. Depending on the cells, they may be the limiting factor rather than the series connection.

Which is pretty much exactly what ShutterShock told you the last time you asked this exact same question.

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Lmao thank you for realizing this

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@ceasium

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Last time I asked about 30x0.2mm this time I was asking about 30x.15.

They are p42a

In that case, i’d be more inclined to do it like this

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Doesn’t really matter, because the nickel isn’t the bottleneck in either case.
See below.

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anyone know where to buy the white silicone stuff thats insulating the PCB of that BMS

I’m pretty sure this is it. I have been considering getting some for a while, to try my hand at sealing up a JST wiring harness the way they come from the factory.

@poastoast could you post some pics of those wiring harnesses that you sealed up, and maybe an explanation of what you used and how you got them so clean? I’m still super impressed by those pics.

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Oh that Kafuter company is the one that makes that horrible yellow hard glue stuff too

yeye! gimme a second, I might be able to recreate it

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here you go :wink:

in text, get the LET just about flowing a very slight amount and keep slight pressure on the tube, like barely any, just to keep ot going nice n slow as you drag along one side of the connector

it should do the wicking on its own, no need to force it through
then flip to the other side, do the same thing
and ethen let it rest vertically so the LET can form down to the wires more than soaking into the connector deeper

you can go back in and add a little more if it’s not enough, but a little can really go a long way!
it’s not factory perfect but it’s failry close with some practice


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Excellent! Thanks for posting that.
Something that has worked well for me, to neaten up things like this, is to place a wrap of painter’s tape around the wires just above the connector. When you finish you can peel off the tape and have a beautiful straight edge for the top of the goop on each wire.

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Just realised I have a nearly 2 years old pack with a D140 bms in it. At end of charge sits at a whopping 109 C.
Pack seems to be fine, a little out of whack though. But I wonder how much of that goodness it has sucked out of it during its time. :laughing:

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I have seen more of those bms fail than any other bms… except maybe the evolve ones :rofl: get rid of it! Its garbage!

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Yeah it sure is a nice space heater :grinning_face_with_smiling_eyes:
I dont have much love for that battery anymore, it has been collecting dust for the past few months.
Wanted to test out a few things and didn’t want to tare down any of my other boards. And realized it by burning the back of my fingers on the damn bms

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Funny though back in the days it used to be the most trusted bms. :laughing:

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I remember. Fuck knows why.

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Bookmarked, thanks poast!

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I’m sure the answer is here somewhere, but 19k replies… I just want to check my wiring before I plug everything in and burn the house down.

I have four 5s lipos and I want to wire them in 10s2p. As seen in the top image, I’d create two 5s2p and then wire them in series correct?

For the balance wires, I’d have the first balance wire from both packs (in the 5s2p that supplies the negative lead to vesc) connect to the first pin on the 10 pin connecter, and the the second balance wire from both packs to the second pin on the 10 pin connector, and so on.

Finally, I take the negative balance wire from each pack and wire those all to B-?

The series/parallel connections look fine.

The balance leads won’t work. You can’t take all the negatives and combine them because you have them in series. The voltage on the negative terminal of the first set of parallel packs is 0, while the voltage on the negative on the second set of parallel packs is ~18v. Putting those together will short circuit and burn up the balance wire.

After you configure the pack into 10s2p, route the balance wires as if it’s a 10s pack.

You will need an 11 pin balance connector and a 10s BMS.

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