Which end terminal battery solder is better?

[frk1206]

I’m building my battery using the copper / nickel sandwich method. I did the negative side wire solder like this which is kinda yucky:



Then I had a idea and did the positive side directly on copper. Way neater since I was able to do the solder prior to welding:


should I redo the negative one like this? Or are they both okay? Not going to draw more than 40-50amp continuous from the battery.

 

[liveforphysics]

Whatever thermal damage that may have occurred has already happened. Watch for abnormal self-discharge behavior from that cell group for a few days with no BMS attached.

 

[frk1206]

Whatever thermal damage that may have occurred has already happened. Watch for abnormal self-discharge behavior from that cell group for a few days with no BMS attached.

Oh no you think it’s that bad? I thought some quick soldering not directly on the top of the battery was okay. I can take these cells out and replace with new ones so all is not lost.

 

[chuyskywalker]

Sidenote: In the future, don't do this. You run the risk of missing and welding through the side of the cell creating a weld from negative to positive on that cell.

 

[frk1206]

2022-09-20 09_57_55-Which end terminal battery solder is better_ - Endless Sphere.png

Sidenote: In the future, don't do this. You run the risk of missing and welding through the side of the cell creating a weld from negative to positive on that cell.

Yup thanks that was a dumb idea. I was trying to make it look pretty

 

[docw009]

2022-09-20 09_57_55-Which end terminal battery solder is better_ - Endless Sphere.png

Sidenote: In the future, don't do this. You run the risk of missing and welding through the side of the cell creating a weld from negative to positive on that cell.

Yup thanks that was a dumb idea. I was trying to make it look pretty

The fishpaper washers on the positive terminal will add a little insurance against an errant weld hitting the edge of the can.

 

[amberwolf]

Sidenote: In the future, don't do this. You run the risk of missing and welding through the side of the cell creating a weld from negative to positive on that cell.

Would that make a new turn of the old "hits the fan" phrase, as "when welds hit the can"?