I didn’t weld them myself, but I’ll do it that way next time.
Who welded them?
The cathode of the cell is right in the center so this is frowned upon… other than these two criticisms I think you did just fine. Can’t learn everything all at once…
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Have you built your first battery yet?
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How many of these did you get Alex?
Welded by @Skyart
I did solder between them so they didn’t get heated as directly, but are you saying i should only solder to nickel over the sides of the cells?
I do whatever I can to keep heat away from cells… granted it’s going to happen regardless at times.
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Sounds good, thanks for the help.
you are ok to solder in-between those cells. That nickel will soak solder fast enough so you don’t have to worry about damaging the cell. But yeah generally you would want to solder onto a tab, I’ve done it both ways, and the packs are still out there pumping electrons into modors.
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Yeah, I’ve built a few 
If you’re forced to solder on top of cells as you’ve done, ideally you would do w smaller wires. 8awg is way overkill for the current that will be carried. For the cells you’re using and the spot you’re soldering to, you could’ve used multiple, smaller wires and transfered less heat to the cells as a result.
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I based the 8 AWG wire choice off of this chart, and I split the ends so that each joint was about the same size as a 12 AWG wire, which seems to be a popular size for serious connections. Where would you say I went wrong in that process?
I think 10awg would have handled your max load just fine, at the same time, people are kind of nitpicking here
Splitting the 8awg that way probably enabled much less time on top of the cells than the full wire being soldered.
It all depends on how good you are at soldering, done properly, I could probably solder a small 10awg joint onto nickel like that in under 20 seconds, whereas a person newer to the techniques and whatnot might take 30-50 seconds or more depending on how much they struggle
It’s all relative
Ultimately the goal is just to reduce heat soak into the cells
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Nothing per say “wrong” with what you did. You requested feedback amd that would be my comment. 1 x 12 awg would have been sufficient to carry that current. It’s really a consideration of continous current vs peak current. As @ShutterShock rightly points out, we’re a fickle bunch and this thread is all about the fine tuning of the craft of building batteries. Ultimately your pack will work just fine.
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Sure thing, in the future I could use 10 gauge for these short runs, and the heavier stuff for longer runs were it doesn’t connect to the cells.
Absolutely, the joint became completely flowed after three to five seconds of heating. Didn’t take too long to solidify either, I think.
Thanks for your two cents. So far I’m gathering that I definitely erred on the side of caution with respect to conductor amp capacity, I can get away with a little less in the future.
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Here are my first attempt at series solder joint, tried to be as fast as possible but I am not sure.
Would you rate my blobs?
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They’re definitely going to hold, my only suggestion would be to prep a little wider of a pool on the nickel, based on the dots I see on the left.
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I noticed that and after the first 2 I added solder to the tabs let them cool and soldered the cables. I need to re-prep all the tabs beforehand.
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I see a wavy pattern in the surface texture of a couple of them which means that the solder is melting and refreezing. You might need better thermal contact with the iron or slightly higher temps.
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Could also be that he just reheated that spot multiple times without letting it melt completely.
Personally not a fan of the solder spots:
Middle left
Bottom right.
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I would have just used a smaller size wire, but more than one piece.
A lot of times I will use two 16AWG into a 12AWG or three 16AWG into a 10AWG
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