The same discussion happened awhile ago, when I posted about some new Fujitsu pack. I don’t remember all the details, but you can try to look for that. Someone else said the same thing, that really “new” packs would have batteries with low voltages, and I think that I did find some website that said the same thing, but I don’t remember if it was posted on that earlier thread.
On the earlier Fujitsu pack, I was about to dump all of the gray CGR18650s until I found that info and someone posted confirming about the low voltages, so I kept all of them and charged them as I mentioned above (put them in a charger that doesn’t check for low voltage for a few minutes, then fully charge them in a normal charger), and they all work fine as of today.
If I bought a used pack, and it came out with all batteries with low-voltage, I’d be dumping them like everyone recommends, but at least personally and from my experience, new packs, if you can get some assurance that they are really new, are different.
Not recommending anything, but check the info out for yourself and decide.
EDIT: Here’s a link to one of the posts from that older thread about the Fujitsu pack:
Thanks ohaya, very interesting reading that seems to raise more questions than it answers. Anecdotally it seems the cells in that thread have been fine under a variety of tests.
It's great to see you posting so much useful information on this topic.
The key would seem to be NEW, NEVER USED packs if such a thing can be guaranteed. At the right price and with the current shipping and postage issues, laptop pack salvage may become a much more attractive proposition for many of us.
At least from what I can tell (cosmetically and electrically), the ones in the OP are really new. I took the risk of getting one, and am reporting what I found, to try to mitigate (but not totally eliminate) the risk in case anyone else is interested.
I’m still charging the batteries, and will:
Measure voltages off of the chargers, and report something like an average, and if any are significantly different from 4.20 +/- 0.05V (FYI, my i4 and TF 4-bay chargers seem to tend to terminate over 4.20V in general)
Report if any of them lose significant voltage over some undetermined period of time
Run some discharge tests on random fully-charged batteries, and report my results
This is what I’ve done with other packs that I got that I found and that would be “generally available” after my initial purchase, but that’s about the best that I can do.
This post has made me curious. What is the highest mAh for 18650 cells anyone has reported finding while harvesting, anyone remember some figures around 2600 or above?
Thanks for the updates everyone. If harvesting is going to become more popular, makes me wonder if it would be worth it to renew and get behind the spreadsheet that Aftrburnr floated in August?
I was the “OP” in that thread also, but couldn’t remember how we ended up and didn’t go through the entire thread. I think that you are correct though :)…
Still charging batteries. One came off of a TF 1 bay charger about 3 hours ago at 4.22V, and is now 4.20V. Waiting to get more of them fully charged, running 5 different chargers simultaneously, including 1 battery on my Accucel 6, which is now at 1965 mAh and still going :)!
EDIT: One of the batteries came off the Accucel charging - 2043 mAH - 4.18V - 167 minutes. For some reason, when I charge batteries on my Accucel, they always terminate at slightly less than 4.20V. I’m waiting for a couple more to complete, then will run a discharge test.
So, so far:
- Battery1: Off TF 1 bay charger at 4.22V - currently (3+ hours) 4.20V
Battery2: Off Accucel charger at 4.18V - 2043 mAh charging
Gonna be a long night (may not complete the 12 batteries tonight :laughing:…
EDIT 2: I started a discharge test on Battery1. It’s already at 2364 mAh and 152+ minutes and still going on my Accucel!
What is “Li-lo mode”? I am using an Accucell 6, and it was set for LiPo (which is what Accucell calls the 3.7V batteries) and cutoff voltage 3.00V.
EDIT: Ahh - re-read the manual, and there’s “LiIo” mode, 3.6V. Is that what you mean? Also, if I set that, does it automatically change the cutoff voltage for the discharge, or do I need to change the cutoff voltage manually?
I don’t know about your Accucell, but my iCharger has a lower cut-off and reconfigurable minimum voltage that can be set. I think yours can do such a thing too. Yes, the “lilo’ mode it is.
You didn’t answer the other question: You’re thinking that these batteries might have more than 2420 mAh capacity (that’d be good, right?)? I’ll try that, but not tonight since it’s 02:45 now :).
Also, BTW, every battery I’ve taken off the chargers after termination has been 4.20V - 4.22V so far.
And, also, I want to do a test later that I did before with another set of battery pulls, run an XM-L2 DD with a clamp meter. The last batch I tried got 7.9 amps when I did that (just really, really briefly).
Seems like ok batteries?
The one thing I noted that I don’t like is that the wrappers seem kind of flimsy.
