New Battery Build: 12s5p Lishen LR2170LA


Glued 9 out of 12 p-groups so far. Waiting on the last 15 cells to charge.

Charged each cell individually to 4.2 so they should all be even when soldering into parallels.

Now to cut some Nickel… How should I do it? I wish I had a die to stamp my shapes out with.


Well there’s 24 tabs cut.
Next is welding the groups, will get on that tomorrow.

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Not nessesary, in fact, don’t do this. If the cells arrive at different voltages you should be concerned. They be should be within 0.001v. This makes it less safe to build as any short will now be stronger.

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CANARY Heavy Duty Aviation Snips Spring Loaded Tin and Metal Cutting Scissors for Straight Cut and Wire Cut (Arm Wrestler Hard Snips Long) Amazon.com

Use this. Make sure there are no sharp corners and that anything remotely sharp has fishpaper under it (whether it’s an insulator ring or just a piece of fishpaper.)

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I don’t have anything that tests cells that low, my nitecore d4 showed all cells going in at within 0.01v of eachother. Once I solder together the p-groups I can discharge each group to an appropriate level.

I charged them all to 4.2 as that’s what my bay charger automatically stops at and I wanted a way to make sure they were all as even as possible.

There is quite literally a battery builders thread for this type of post mate…

Zero reason you should ever need to do this. And if anything this is a bad idea because you’ve now raised the potential for hazard when handling the pack. Touching the ends of a fully charged 12S pack will be noticeable. If you haven’t finished the build, or were to ship this pack you now need discharge back down to storage.

Generally scissors work, but you’ll wreck the scissors over time so don’t use your moms favorite or anything. An upgrade would be non serrated shears.

Don’t bother, buy a good multimeter asap.

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Neither do I. This is perfectly ok. They’re so close that nothing bad will happen and it’s perfect to build with these.

Probe all of your cells before you use them and make sure they’re within 0.01v in your case. Any outliers should not be used.

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I’ve got some flush cutters and industrial scissors I’ll use. I’ve been practicing making rounded cuts in the nickle (concaves are still hard)

You do you, but those metal shears will change your life.

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Might try them for my next battery, or if my current tools annoy me too much.

I have a cheap DMM, the good one comes when I can afford it.

Sure I can totally do that, I plan to after welding on the nickel. I’ve read that a light bulb is an easy way?

The main purpose of the charge was to ensure the cells were as close as possible when going into p-groups

If the cells were purchased new from a reputable dealer, then that’s not a concern. They’re shipped at storage voltage and in most cases, should be built into a pack in the same state.

Oh well, I’ll just have to discharge them and lose half a cycle. Any reccomendations on discharging back to storage voltage? I’ve read about using a light bulb.

If they’re already glued or welded, not really aside from using them.

As you said you currently can’t afford a better multimeter, I’m assuming an electronic load isn’t something in your budget.

I use an electronic load to discharge packs, after charge testing completed builds.

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In the future I plan to acquire an oscilloscope, an variable load and a CC/CV power supply, but currently I’m just trying to gather and master my necessities for assembling packs.

Better tools will come as I gain experience.

I understand that pre-charging the cells makes this more dangerous to work with, but if I’m worried about that then the pack isn’t safe enough. Nothing should short or spark if this is assembled well.

Anyway, after a dozen posts about that, back to useful content.

Anyone have suggestions on what shape I should cut my nickel? I’ll be doing wiring on top as I have the enclosure space to do so.

Dodecahedron
Aka

Uhh, really?

And yes, I have read and continue to read that thread.

If you’re going to troll and not be helpful you really don’t need to comment.

If you did read the thread you wouldnt have needed to make this one :thinking:

The point is, questions like these are better asked in the battery builders thread so that any assistance given is localised for future reference.

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I’m documenting my build, what’s wrong with that? I thought that was what people did here.

You should do that in the battery builder’s thread. That’s what it’s there for.