OffGridInTheCity said:@Daromer did a youtube on recovering 'really low' volt cells - ones that are too low for OPUS to even begin to charge.
Its simple, and I used it successfully myself. See this video -https://youtu.be/n_MKDta9M_I - and in particular I did the resistor approach detailed at @4:10... in the video.
In my specificcase - I was processing 2,000NCR18650A(s) of which many were 0v when I got them- and unfortunately a fairnumber that seemed to recoverturned out to be heaters as they got past 4.0v. So just because you get them to charge it doesn't mean they will actually be suitable - just make sure you follow a good protocol (check for heaters, let sit for couple of weeks to find self-discharge, etc).
I give it a try with a battery with 0.13v at first reading from harvesting... and used the EBL single charger.... and start with a green light like it's fully charge... after 10 mins... turn to red... I will keep you posted...jonyjoe505 said:I looked at the reviews of the ebl and didnt see too much info on recovering batteries.
The one I myself recommend is the foxnovo 4s. That one is my go to charger to recover 18650. If this charger can't revover it, the battery is totally dead. You put the battery in the slot and it checks it and tries to put a charge in it, if its too low it will stop, you remove cell, put it back in, sometimes you repeat several times until the battery is jumpstarted and starts taking a charge.Anything above 1.5 volts will probably be good, anything below 1.5 volts even if recovered will self discharge or be low capacity. Anything above 2 volts is usually a good cell that wont give you problems. I have 2 opus and they won't recover anything.
Recently I had about 140 cells, about 40 were below 2.5 volts, 10 were about 0 volts, I didn't bother with the "0" volts, they rarely work good after recovering, but the foxnovo was able to recover all the rest of the low cells.
If you can find one of foxnovo 4s, its a great charger for cell recovery, and it also does capacity test.
Overmind said:On the Way 18650 3.7V 5000mah ?
I was expecting a serious top.
I agree with Samsung 30Q being #1 from what's there, but what are the junks doing in the top ?
in parallel with B+ & B- ?kc8adu said:i use a tp4056 with about 13k iirc.
it starts low anyway and i limit the charge to 100ma with that config.
i have been surprised at some of the 0v cells i have treated with this.
mostly newer cells that have not sat dead long.
old junk is still old junk though and most are poor if they do anything at all.
gotta choose your battles.