The battery builders club

[Bindings_McGee]

Like, how much of the large strain relief could be cut off?

[glyphiks]

Oh, like all of it. But it doesn’t really matter… that would be the charger plug,

[Bindings_McGee]

Yeah, I was just curious if at bare bones it had potential for an external floating sensor connector

Narrator: It does not.

[Pedrodemio]

Any tip on making fish paper stick better? Or mine is just crap? Everything cleaned really well

[glyphiks]

It doesn’t like staying down around the curves. Stick it down with kapton to keep it from lifting.

Or shape it by rolling it tighter in that direction before you stick it

[Pedrodemio]

Thanks, will try that

[Darkie02]

@Pedrodemio

Any tip on making fish paper stick better?

@glyphiks

Stick it down with kapton to keep it from lifting.

You want the tape to go all the way around and stick to its self like a elastic band

[Pedrodemio]

That helps, will see if it’s needed when I stack all the packs, I’m trying to use as little as possible since I have to finish the board with what I have on hand

Thanks guys

[esk8manbabes]

It’s also the glue of the paper. I had a bunch from nkon before and they stick really well.
I ran out and bought 10meters from AliExpress and it hardly wants to stay stuck at all.

[ZachTetra]

So my 12s3p shorted out…chance of salvaging it?

Cells are still cold, voltage is still 41.4V

There was 0.25" of wire in the negative end I was soldering and I got solder splashed on my hand and dropped the lead…and then it poofed. Big spark, a bunch of soot, be the tinned but if wire is just gone, kinda melted into the other end of the connector

After wiping the soot down

[Skatardude10]

I’d personally check each P groups voltage, but I’m sure it’s still fine. Did you not isolate and only solder one lead at a time? Like, solder one lead then tape it to make sure it doesn’t short? this looks nasty, glad you’re okay.

Edit: those cells on the end look burned… scary… now that I see that I don’t know how I’d feel using at least that P group.

[ZachTetra]

Usually I wrap with shrink wrap but I forgot to do this one

I’ll check the voltages, one minute

[Skatardude10]

Do you have fish paper between each P group?

[ZachTetra]

Yes all parallel groups are isolated with fish paper, it’s siliconed between them so it holds as a giant block

All cells are 3.45V exactly

[Skatardude10]

Nice.

I won’t be the one to say use this pack after that… I’ll let someone with more experience chime in at some point.

[ZachTetra]

@Skatardude10

those cells on the end look burned

It’s just soot, I gave it a light rub with a paper towel, clean as new

[ZachTetra]

Okay so I put a new connector on and used shrink wrap this time…no evidence of it being damaged at all. It’s only gonna realistically be drawing 5A per cell and all the welds show no sign of damage from the high current spike.

This board will have a 100A fuse on it, packs will be rates for 105A when in parallel

Im not worried about capacity, just about if any of the cells will poof under light use

[tinp123]

Nah I wouldn’t worry. But ask @glyphiks, he likes to short batteries

[ZachTetra]

I really hope so, I can’t afford a fire, or new cells

[iamasalmon]