Someone just posted a list recently in a different thread. Liionwarehouse, IMRbatteries, MTN, 18650something, etc.

“Counterfeit” can be decent if the cells are in fact decent. Crap cells are those that are pulled from ancient laptop batteries and rewrapped as “new”. I got “genuine Liitokala” cells for <3bux a pop, knowing full well they were LiShen or equivalent. And they all clocked in at close to their rated capacity. Close enough, I still gave them 4 stars for trying. For the price, though, they were okay.

Prime cells, expect to pay maybe 4-5bux each. I got 30Qs from Fasttech without issue. Still using ’em in my Q8 (BTs) and in other lights (FTs).

The US-based companies that’ll be mentioned will pretty much guarantee legit cells.