Big Question


New member
Dec 10, 2017
Ok so I have been working with and on recycled 18650 for a number of years. I work in the IT industry and have been able to source used laptop batteries on occasion. I have not build any packs or really decided what to do with the batteries that I have collected but I recently got and incredible opportunity to gain access to a huge quantity of used laptop batteries actually 1000 packs. Each pack has 9 18650 batteries within it. Here is my question for the community. The processing of 1000 packs is enormous on its own ha ha. What I would like to see if there is any opinions onleaving the cells in their three cell spot welded configuration. My thought is that these cell have already been together from there inception and it would allow me to process these faster. I know that there will be bad cells but they should show themselves in testing and then I can test to figure out which of the three is bad and deal with it. I would just treat them as 9000 mah cells. My intent with these cell is to build a large powerwall. I am currently charging them as sort packs on imax b6 with 4 packs at a time so a total of 12 cell at 5 amps. And this could be the issue of testing them on a opus at 1 amp discharge. I know this will not be testing each cell at 1amp draw but it would be testing each group of three with the same load to determine like cell packs. Any feedback would be much appreciated.


Staff member
Oct 8, 2016

I would say its perfectly fine to leave them spot welded and several people here does it. They have been used together and aged together and most likely will be working like that for some time more.
The Imax can though only test 1 pack/cell at a time so it will take some time.


Active member
Sep 2, 2017
Yes, you can leave them like that if you want. This saves you a lot of time. However, they won't fit in 18650 holders and you can't fuse individual cells. Not sure how bad that would be with 3p configurations though. Just something to consider.