Chanced onto a dell laptop at work today.Pulled apart the battery and got 9 CGR18650EA’s, my first laptop pulls!It was a 3s3p pack, two three groups were at 3.2 volts and the other group is at 2.75.I brought two home and am charging them on my new VC4 from RMM.They are charging well at .5 amps, showing almost 2000 mah. at 4 volts.So my question is, what is there rated capacity, and how old are they?The code on the bottom of the cells is Ey.Below that is 8z20.I am going to charge the others at work tommorow with my XP6.I think I was missing the boat on these laptop cells? :quest:
The batteries might be these : http://www.houseofbatteries.com/documents/CGR18650E.pdf
I had really good luck with a pack once: https://budgetlightforum.com/t/-/19326
Historically I seem to get a run of bad packs, followed by a few good packs, probably about a third of the packs I find have good batteries.
By good I mean retaining voltage over time and doing more than 75% of original capacity when discharged at 1amp down to 3 volts on a hobby charger.
Best so far was 9 cells with 2600mah.
Here's the quick battery qualification procedure I use, put together from the experience of others.
1. measure cell voltage. if it's less than 2.2v, dispose.
2. charge the cell. if it gets hot during charging, dispose.
3. measure cell voltage off the charger after 60 minutes, if not 4.2v +/- .05, dispose,
4. let sit for 24 hours and check again, if it drops by more than .1 volt, dispose.
5. discharge at 1 amp with hobby charger - if capacity < 75% of marked capacity, dispose.
Well I finished charging the other cells at work and they all seem to be good.Charging from 3.2 up to 4.18 they all took right around 2350 mah. or so.They all terminated charge at about the same time and didn’t get warm charging at .5 amps.I took one cell and tryed it in my S6 and got right at 2.8 amps at the tailcap, same as the 18650B that was in the light!Now I am going to let the other 8 cells sit for a few days and see if the hold voltage.One question I have is what is the best way to remove the sharp pieces left over from the tabs?
A twisting action works well with long nose pliers.
This kind of action
re: Removing leftover tab pieces
Try a Dremel or some other brand of rotary tool.
Some folks also use small files.
A dremel or similar as 202bigmike said
Although I tend to now leave some of the tab on and round off the sharp corners of the tab and fold it back over
That way I can use them in flashlights that won’t work with flat top batteries
And I don’t have to resort to using magnets or a blob of solder
One, you could use the points (since they’ll heat up very quickly) to stick solder to (cooling the end after each point), then get the tip close & push solder into the tip until it starts to drip, and let that drip bridge the little point-solder blobs… I would if I needed a protruding end…
I am lucky to have a set of needle-nose pliers that meet perfectly at the tip. Yes it took some grinding and work on a diamond hone to get that way, but that’s because I’m too cheap to buy “the good stuff”! 
Anyway, here’s what helps me: First I remove the buss bar (that strip of metal) by grasping it as near a pair of solder joints as possible with the tip of some pliers & rocking the pliers back like pulling a nail. That will often pull the welds clear without leaving the tips. Okay YMMV on “often”, but it’s worth the trouble IMNERHO.
As to the tips, I look at them as a weld and a point. I grab the point with the fitted needle-nose pliers & rock it back onto the weld (like opening an old beer pull-tab) to peel the weld away from the battery. I tried Flush Cutters to ‘filet’ the welds off, but that didn’t work for me — although they do work to clean up the last bits the needle-noses leave behind sometimes. And when I try to file off the points it usually cuts the wrapper somewhere. I have a Ball cutter for my Dremel which I am working up the courage to try…
Lastly, welcome to the secret world of FREE POWER!!! Nyah-ha-haaaaa! Your CGR18650EA’s are ostensibly from Panasonic and seem to be rated at 2550 mAh, meaning you’re close to “like new” with yours. No offense, but as to your question re: capacity, I’d have to ask “Who Cares?” They’re free, carry spares. You’ll soon be busting a pack with 6 or 9 more better batteries & these will be pushed back anyway. Whenever you do, Google the string with 18650 in it for details. If you’re any bit like me, before you know it, you’ll have charged 18650s stashed away in every squirrel hole “just in case”, and be looking for more holes to put them in. But that’s just me.
HTH…
Dim
1+
I don’t quite understand the need to rip the tabs off then grind down the remaining sharp bits. Only to what, add a lose magnet or ugly and soft solder blob?
Trim, fold, burnish (smooth edges by rubbing metal pliers handle over it).
Its quite flat and smooth, despite how the close picture and reflections might make it look.
Anyone else do this?
OMG! I could see the edge of that tab catching the end of a spring on a Nanjg 101 and twisting it right off the PBC while screwing the flashlight together. Tell me I’m wrong please.
The tab metal is very thin so the edges are very low profile. And the edges are burnished, feels smooth.
Even if I make a hook out of it designed to catch the Nanjg spring, a battery can spin freely in all my lights. H) I’ve checked them for catching. The tail tabs aren’t folded over.