Portable lithium battery has some dodgy terminals

I pulled apart a powergorilla 21,000mah lithium battery today because it was obvious some connector had broken.

look at these two videos and let me know if what we are seeing on the inside of this unit is what youd expect? Because I think this unit was manufactured poorly. every single cell has the same single terminal with a very flimsy connection and orange tape over it in the same place. One connection was already clearly broken on disassebly and after closer inspection they had all split at exactly the same point.

this video is a little clearer on the issue

ignore my gibberish about conductive tape, thinking without speaking :slight_smile:

the connectors appear to be soldered into the board, so maybe if it isn’t too dangerous I could solder them back. Possible? or should i forget about it?

inside the cell there are two plates, of dissimilar metals, and sometimes these are hard to solder metals like aluminium, other times they are copper. Sonetimes the tabs coming out the battery are a continuation of this metal, sometimes they are a diffErent metal entirely, like stainless.
Id speculate that the manufacturer has chosen to use Cells where one side of each cell is made of a material that does not take solder, so the construction is more of a “press fit” , with the pressure from the case being intended to keep the tab and pcb in contact.
I personally think its a shit idea, but I don’t design batteries. Normally these tabs would be spot-welded , making a secure and non-soldered joint to the cell.


Thanks Buzz! I’m guessing its to prevent the risk of a short or something from an impact. after impact it would just disconnect and a short would be unlikely.

In any case, those tabs wont have solder sticking to them, they seem too rigid for aluminium, I think they are stainless. Any ideas on how I could bond those connections together? they sell these batteries for a lot brand new, and I love the thing, its lasted 4 years and I’m sure the cells are still good.