Q about A123 solder tabs

[pinkpanda3310]

I got a hold of some disfunctional dewalt batteries the other day. 3 cells out of the 30 are no good. The rest i'll reconfigure but I want to know if the existing tabs are sufficient for the purpose? They are kind of crimp welded (i don't know the tech. term)

[whitrzac]

rip them off...

were did you get the batts???

[pinkpanda3310]

I got the batteries from a tool shop. So you recomend I solder all the joints?

[MetalMan]

From my experience the tabs are fine, except for the one skinny tab in the pack that was meant to act like a fuse. All of my A123 cells came from Dewalt packs and for the majority of them I cut the tabs apart, and soldered the cells together using the tabs.

If you pull the tabs off, you have to be careful not to remove aluminum chunks from the cells. And when the tabs are off, if you solder them you have to use aluminum solder. Those who have dealt with it know why it's not fun, especially with that many cells.

[BrianG]

If the thin tab is too small, couldn't you solder a ~16GA wire along it to "beef it up"? The combination of existing metal, solder, and wire should provide at least the same amount of wire cross-section of a 12GA wire or more...

[JThiessen]

I used some "desoldering" mesh wire when I did mine. Dont know if it was something that will last, but battery performance was fine afterwards.

[snellemin]

I put battery bars with regular solder and a 40W weller iron(fat tip). I either removed the stock tabs or solder the battery bars directly on top of the stock tabs.

[pinkpanda3310]

So it's not the actual connection but the tab itself that can be improved. I may just solder over top of them as suggested. Thanks for the help.