First Harvest

Got my first harvest of batteries today, I had to take the lot i couldn't just pick what i wanted but i do notmind ill send the ones i do notuse back to the recycler.
Got a couple of UPS's im pretty sure they are lead acid batteriesas they are heavy - Will pull them apart and have a look as i might be able to use one of the units for my 24/7 NAS if its still working.

I haven'ttested any of the cells yet as i gotta find my old fluke in the shed. I also got a pack with some bad leaking Samsung cells 4 out of the 6 look visually stuffed but i kept them all in a separate tub and will test the 2 that look half decent. Also the 2 tubs on the far right of the group pic either are heard to read or have nothing on them at all, Im thinking maybe cheap knock off cells??

I am also waiting for my Opus BT-C3100 to charge my Eneloops up as my kids useso many throw away batteries i decided to buy bulk Eneloops as i get them at cost price but read that it can also charge 18650's!! The Panasonic Basic charger has no information on it other than a green light that stays on forever.

Im still not sure what i want to do with the 18650's yet, A DIY Powerwall for my Solar would be ideal but ill just start the collection & testing process first & keep reading & researching.


Questions:
1. How do you guys clean the little sharp bits on the ends of the cells left behindfrom the spot welder? Tap them flat, file them down, fine emery paper or just leave them.

2. Can any one link a 18650 cell holder that i can hook my Swallow Charger to. It says it can charge 1-5 cells @ 5 amp so i should be able to hook more than 5 cells to it as i do notwant to charge them at 1 amp correct?

Good haul. The UPS's should still work. Most people throw them away when the batteries die. However they will most likely be 12v and not suited to LiIon conversion. If you could source LiFe batteries 4s works for 12v.

I have attached large batteries to my UPS for my modem. But it is advisable to add a fan, as home/office type UPS are not designed to run any longer than the original battery would last.

Answers to your questions:

1. I don't try too hard to remove the 'sharp bits'. If you file/sand/use an abrasive on a cell it will most likely lead to corrosion. It is best to simply grip the strip and try roll it off. Side cutters or flush cutters are the tool of choice for this. For high discharge packs (often found in power tools or e-bikes) often the spot welds are so strong that the nickel will tear a hole in the cell when removing it. The best option is to cut off as cleanly as you can, and leave behind what you cannot.

2. If you use the Swallow Charger to charge multiple cells they have to be hooked in parallel. You can hook as many as you like. If you hook up 5 then you can charge at 1a per cell. Hook up 10, that would be half an amp per cell. Also don't parallel cells with a voltage difference that is greater than about 0.1v, otherwise current will rapidly flow from the more charged cells to the less charged cells. This will damage the cells, generate heat, and potentially cause a cell to vent.

Another handy tip with charging batteries. If you have a 4 cell holder you can charge 8 cells at a time. When I remove the cells from laptop packs, I leave the strips attached to the 2s groups, you can charge them while they are still attached. Makes voltage checking go a little quicker too.

Aliexpress battery holder 18650