Use a pliers and pull the nickel up, then turn the pliers curling the nickel, now pull across the stop so the angle is close to 0* backwards. It will put more sheer force on the welds and should mitigate the damage to the cell vs pulling upwards.
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How smooth does it have to be, Like perfectly flat or just no nubs of nickel ?
Flatter is better, but as long as the little weld nuggets are gone that should be fine.
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I tried to remove to bottoms, but each time it went less than ideal. So I think that I am just going to weld around the old strip( and some welds on the old one too) I did all the tops they came off way nicer. When I was originally welding the batteries I decided to put a butt ton of welds on the bottom.
I know you should never reuse nickel strips. Just cut a new fresh strip.
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You and I have very different definitions of “rarely”.
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when I mean “old” I mean the nickel already on the battery
what do you think?
I know they are not the cleanest, but they were pretty clean in the begging before I went overly cautious and added like 1000 more welds
The welds, both in their numbers, and inconsistency of temperature, are a bit concerning.
Also their spread. Looks like they’ve hit cell shoulders, the centers, and in some cases are either cold or nearly blowing through.
Which welder are you using? I didn’t see if it was mentioned earlier.
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Yeah don’t do that. AVOID THE CENTER OF THE NEGATIVE TERMINAL. There’s an internal cell connection that can break.
You only need 3 sets of welds (6 dots) as each dot conducts ~5 amps cont.
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thank you.
try to avoid the dead center (3mm diameter circle) on the negative side of the cells when welding
also you dont need that many welds. I do about 4 per cell. You rather have a smaller number of strong welds than a really large number of weak ones.
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The sunko 738a
I put a lot because I thought would be better, but now I know less can be more. The reason the welds are inconsistent is because I raised the power level for the last few weld to make them stronger, or so I think.
Is this cell groups still safe to use or should redo it (I really hope I don’t have to redo it)
you dont need to redo it,
just try to follow our advice for the next p groups
this is what my welds look like, 3-5 per cell is what I do
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OK great, and I will 100% follow your guys advise
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When working with any welder, but especially a lower quality one like many of the Sunkko units, it’s important to just make the sacrifice of some cells and nickel in order to learn the proper operating range for the pack you’re building.
One can get consistent results with a low end welder, but it has to happen through a spectrum of power levels and then doing destructive pull tests to see which sticks properly. Not destructive of the cells, but the nickel.
Only when the weld quality for that power level is found and known, would it be wise to proceed with welding groups in what you are assuming is a permanent assembly.
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I actually bought some test cells that are just empty cell, I have been practicing on them for a while and I think I found the right settings
Thats a good idea to get you in the ball park, but different cells accept welds differently. You really should practice on the actual cells you will be using
In addition to this, I find that the positive and negative ends of the cell accept welds differently as well. I use different power settings for each end of the cell
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