The proper way to solder 18650 cells!

Your Mom’s deflecting!! :rofl:

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Hey psychotiller speaking of the same topic. Would you be willing to weld my “lightly used cells?” :rofl::rofl::sunglasses:

Jk

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Umm I have 4 working packs all made by soldering buswire to cells and then to brass busbars and havent had any issues after 1.5 years. Used 3d printed cases to keep cells separate and used plenty of flux but the solder joints are quite strong. Not sure why you say never solder…

@barajabali take on it

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I’ve never had good results just using the flux built into the solder, no matter how good the solder. Just not aggressive enough to quickly tin nickel plated steel. A non-rosin-based flux (I use Ruby Fluid liquid flux for copper plumbing) is much more aggressive and faster.

Also, I’ve never met a rosin based flux that either isopropyl alcohol or acetone didn’t take right off.

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I’m just going to leave this here. Everything is quoted directly from samsung in their datasheets.

“Don’t heat partial area of the battery with heated objects such as soldering iron.”

“Don’t solder on the battery directly.”

“The cell should not be soldered directly with other cells. Namely, the cell should be welded with leads on its terminal and then be soldered with wire or leads to solder.”

And consequently:

“Otherwise, it may cause damage of component, such as separator and insulator, by heat generation.”

Keep in mind that there is plastic directly in contact with these components you solder and giving excessive heat WILL cause damage. That is undeniable. There is potential to melt the separator and cause an internal short no matter how brief you solder cells.

These are NOT like soldering lipos, as those have heatsinks temporarily placed between the tabs and the cell during soldering to prevent damage.

Normally I would advise against soldering cells but its not as bad as people think it is. i recall watching a video about someone measuring capacity lost after soldering for an extended time. It only really affects the negative terminal and the loss is negligible if you do it correctly.

You need a high power iron and tin all parts first.

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this has happened to me before, a little solder bead got caught inside the positive terminal cap. jiggled it around in there, and POP! mini solder explosion when it shorted.

my biggest issue with soldering onto cells is NEVER being able to salvage them. like, weld tabs can be ground off. solder bead isn’t coming off.

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Did someone say channel trucks?

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Lol why would you want to salvage these kind of cells? :smile:

As you can see in the video the only time the solder pops is when it’s applied to the iron in the first place… When the chemicals burn from the solder and the smoking stops the substance is stable.

you had to say something didn’t you

He just wants to see the world on fire

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P groups die frequently…so one P group dies, may need to rebuild the pack. or…pack comes to end of life but still has some viable cells inside. you going to throw those out too?

i’ve salvaged a number of 25r cells from before 30q’s came into favor…using the 25r cells for all manner of non-esk8 related stuff around the house.

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How frequently are we talking?

Obviously it’s not quantifiable in the # of days it will take, but what’s your estimate?

I’m having my battery built by a professional but I’m still terrified of failiure rate

12s7p btw

I salvaged a very poorly built 10s3p (raptor space cell) with HG2 cells and use the cells on my main esk8 light. I carry a few cells in my backpack so I never have to worry about having to charge my light I always have extra cells.

With that rational I shouldn’t have a failiure ever! :joy:

What’s a good indicator or a failing pack? I’ve been assured that it’s going to be relatively difficult to pull a 12s7p out of balance, especially when I’ll be using lower amounts of amps per motor (40, 45 maybe? I’m not looking for a rocket)

That being said, would you think that I should balance once a week? Once every two weeks? :thinking:

I’ll be using a metr module as well as a DieBieMS to look at the technical numbers of my pack, so I think I’ll have a good suite of software

Thank you so so so much for your response. It’s exactly what I needed to hear/wanted to know :slight_smile:

I’ve got one more question… But I’ll come back tomorrow if I can’t find the answer out on my own. :slight_smile:

Thank you!

E: I guess I could set my cutoff to 40/39v and never worry about it :thinking::thinking: not saying I would disregard taking care of it… I just figure that would significantly lower my chances of failiure by undervolting

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I going to pm you an additional question, sorry to keep adding onto the pile of questions :joy:

It’s a quick one, I would think :thinking: