Any way to WELD to Aluminium tabs of LiPo cells?

[izeman]

Is there a way to properly weld nickel tabs to the aluminium tabs of these LiPos cells?
I tried soldering them with different special alumnium flux, but it never lasted very long.
Is a spot welder capable of this? Afaik the nickel tabs are welded with ultrasonic welder, which obviously I don't have.

 

[amberwolf]

This might be relevant
https://endless-sphere.com/forums/viewtopic.php?t=74917


There are also some threads I remember but haven't found (JonesCG?) about nickel-plating aluminum busbars and such so they could then be soldered or welded. Tabs should be plateable too; only need to plate the part you're going to connect to.


Cell-man refers specifically to welding nickel tabs to aluminum tabs, saying that "many" do this, but I couldn't find a reference to a procedure.
https://www.endless-sphere.com/forums/viewtopic.php?t=21519#p314109

 

[izeman]

Thanks amberwolf. I've already read those two threads. I know chances are like zero, but i was hoping that in the mean time (since I last tried some years ago) someone invented some crazy new stuff
It's a shame.
My 150 cell 15s10p build made of 30Q cells SUCKS badly after 4 years. It hasn't seen a lot of cycles, but still some cells are just dying. They see massive self discharge with no real reason. The cells next to them are super fine.
Then I swapped out 10 cells of the pack (was a nightmare to do, as the pack is not serviceable at all) and now some other cells started to sag.

But I still got about a dozen Turnigy/Hobbyking 5000mAh 6s packs that are like 10 years old now and still show storage voltage. Maybe I will reinstall those. Was happy to move away from LiPo, but it seems even those high quality brand named LiIon cells can fail badly

Any prices per cell went up dramatically. I remember having paid around 2.5 per 30Q cell. Now it's more than double that price - well, I wouldn't buy them anyway