I have a friend how has accumulated some old laptop 18650’s.
He has asked to me to recommend a 2x18650 light to use them in.
I know that previously the FandyFire STL-V2 and the TrustFire X8 were good suggestions.
Is this still the case or is there anything newer out there under $50?
I’ll just reiterate, using old laptop pulls in a series light strikes me as a terminally bad idea, are they a matched set? matched capacity and internal resistance? are they even from the same packs or are they all mixed up?
I’d really suggest using them in single cell lights, it strikes me he only wants a 2s light to use more cells up at once, why not suggest he gives a few single cell lights a try out? say an edc nanjg based tube light, an xintd c8, maybe since he seems handy, he might enjoy building a few lights for himself?
but using recycled unprotected pack pulls in a series configuration could really end badly.
I use laptop pulls in series, and it can be done safely if you know the dangers and follow the do’s and don’ts religiously. I don’t recommend using them in applications where you use the light for extended periods. And I don’t recommend using them at all unless you’re willing to be careful about how you treat them.
Does your friend have a DMM? Can he tell you the do’s and don’ts? Does he know how to match cells for capacity and internal resistance? Does he have a hobby charger to keep them balanced? If not, I don’t recommend using them in series.
I’ll have to agree with gords1001. I must bee a wimp or something, I even only use protected cells in singles, over careful maybe but less chance of a “pipe bomb” situation.