Necessary tools for battery building - tips?

Im thinking of venturing into building my own batteries but with the amount of tools and contradicting info i find out there i was curious to see what this forum would recommend.

So, any recommendations on the tools i would need?
I need everything to make a battery. (Apart from typical tools like screw drivers, drill etc…all of which i think are not needed in battery making)

Spot welder?
Good solder kit? (There is some at like 20$ 30$ but from what i read it could/would be better to go with a 60amp one which is closer to 70$ to 100$ if i saw correctly)
Etc…

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you could try looking through the battery builders thread. I’ve seen a number of builders using the Boss Spot welder. Also check for reputable sources of Nickel strips. There are also PCB’s that you can look up by @akhlut if I recall. Jigs to hold the cells also help alot from what I’ve seen.

That’s what I’ve basically read through and I haven’t even been intentionally reading up about build batteries lol

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Check out the boss level spot welder.

I have a sunkko that worked pretty well, but my next one will be on a boss.

Maybe I’ll sell my sunkko…but it wasn’t $20

If you are building a “space cell” Tools required: duct tape and hammer

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Tools are pretty basic outside of a spot welder. The most important tool you will need for battery building is knowledge. Make sure to read alot because battery failures can cost you alot of money. Do it right take your time and never cut corners.

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  • A multimeter - An absolute MUST. No ifs, ands, or buts. Doesn’t have to be a $200+ Fluke, but you GOTTA have one, and know how to measure basic stuff with it.
  • Spot welder
  • Soldering iron - You want one that’s got temperature control, and ideally one with the heater and tip integrated together: Greatly improves performance. The cheapest option would probably be one of the chinese knockoff T12 kits.
  • Solder: Don’t use the lead free crap - it’s crap. 60/40 or 63/37 lead/tin with a rosin core.
  • Nickel strip: You want pure nickel, not plated steel. Either the salt water scratch test, or the grinder spark test will reveal any steel.
  • Fish paper - An absolute must. Kapton and others are great for heat resistance, this is great for abrasion.
  • Adhesive fish paper rings - Keep you from shorting the nickel across cells.
  • Kapton tape - Very heat resistant, not very abrasion resistant.
  • Heat shrink
  • Silicone - You want neutral cure 100% silicone.
  • A heat gun to shrink the heat shrink
  • Conformal coating - Ask @b264
  • Connectors of all types. The balance leads are usually JST of some flavor.
  • Wire. Silicone is best for heat resistance.
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i’d like to take this opportunity to stoke this controversy up again, if possible :heart:

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Always cut corners! It will save you trying to defend yourself against the battery trolls and it just looks so much better. And you will feel better. And there is the possibility that it could prevent a fire.

The tool is called a corner chomper

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A dremel is also a handy tool to have, I use the dremel to rough up nickel strips before I solder to them, but you could get away with just scratching up with something sharp or some sand paper…

But if you fuck something up and need to salvage cells, a dremel is pretty much a must.

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Nice! I’ll add:

  • good flux
  • good solder wick
  • sharp knife
  • jst crimper, terminals, housings
  • hot glue
  • sillycone
  • thin foam
  • painters tape to cover contacts while building
  • solvent to clean contacts
  • filament tape
  • 3D printer
  • fire extinguisher or bucket of sand
  • zip ties
  • lab psu
  • electronic load
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Everything but the 3d printer, PSU and electronic load I would classify as “not absolutely required but very, very helpful”

The 3d printer, PSU and electronic load, I would call “nice to have.” (I have a 3d printer, and used it to make spacers/holders for one battery pack. My design was terrible and it sucked really bad and took forever.) From now on, I’ll stick to either the plastic snap-together holders, or regular old tape/silicone/shrink/fishpaper construction.

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Lab PSU can be used to charge a single p-group or multiple p-groups. Electronic load can be used to discharge test to some extent, discharge high p groups, measure capacity. If building packs (more than 1), hmmm it’s pretty close to necessary. Lab PSU can be substituted with the DPS units (I like the DPH5005, 50v 5a buck boost). Electronic load, you can kind of work around by discharging the whole pack.

I used the electronic load and PSU to test balance lead fuses and charge port fuses.

3D printer, I put there kind of jokingly, but…

  • mock cells and p groups for mock layout of packs and enclosure check
  • jigs to align cells during assembly
  • jigs to align nickel on cells and guide weld probes
  • wire combs to keep balance leads organized and protect from impact/friction
  • cell holders if you have space
  • standoffs and enclosures for bms or other random electronics
  • makeshift mechanically robust insulation
  • fuse holders for charge port inline fuse (LittelFuse Pico series)

I’m sure I forgot a few. Very useful!

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Fair enough. I took this thread as “what are the things I need to safely build one pack for myself, and avoid burning my house down?” and you can get away without a lot of stuff there.

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Yeah no big deal, I’m not being that serious, if you couldn’t tell. But also trying to be helpful and provoke some thought.

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AU $113.36 5%OFF | EBD-A20H electronic load, battery capacity tester, power supply test, model power battery discharge AC
https://a.aliexpress.com/nNrxFiDE

I use this guy. Only tests up to 20a but provides a full discharge graph and all the useful information about the cell in question. I test a few cells from each batch I receive to ensure they are legit.

As I really can only get 30qs for a decent price, the 20a is enough, but I kinda wish I had’ve got something that would do at least 35.

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Nice! That one is 0-30v? Ah I see a ton of similar models with different capabilities, like 12-72v 20a $220 or 0-5v 40a $190. hmmm.

I usually recommend this one at 0-60v 10a 150w one with numeric control, about $30. I haven’t stepped up to more serious units. Link in this post

You can use that little one to drain a pack (slowly) down to storage charge, among other things.

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Yeah 0-30v, 200w, 20a.

I thought that the watt rating might be the true limiting factor, but it appears I was wrong, 20a is definitely a limit.

That 0-5v 40a one sounds good… maybe I’ll sell mine to my mate and buy that one instead…

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Hehe nice strategy.

Here’s another janky angle. I’m not actually knowledgeable so I asked an engineer if it might be okay to use those $30 loads in parallel.

We dug up the schematic, and he thought it might not blow up. :slight_smile: It’s probably a bad idea, but 4 in parallel will do 40a. It has 4 wire sense so you can get accurate voltage readings.

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Hahaha, i’m happy to pay the money… if I start a fire in my studio there’s a lot of firepower in there :grimacing:

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This is weld bullying.

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Eeehehehe install a security camera so you can post the epic video if it goes off.

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