I have a few lights, nothing special, and they all seem to need a new battery as the charge in the 4 I have drains fairly quickly. I bought a charger and 4-6 cells from a member a couple years ago. I believe they came from a laptop battery.
I do not mod lights and I don’t get into the specs and details of them. I don’t know which 18650 cells would be good and which would be inadequate. Should I get protected cells or not?
If anyone has any to sell that are good or are thinking of placing an order but don’t need all that are in the “deal” or special, I’d be willing to buy a few with you if the price isn’t so much.
I haven’t tested or used every cell out there yet but, if I am using a light at less than 1500 lumens or so and I want a nice long runtime I normally use LG MJ1’s. 10amp 3500mah cells that are so far doing very well for me. I also have a bunch of Samsung 30Q’s and Sony VTC6’s for my more power hungry lights. I bought a boat load of LG M26 10amp 2500mah cells not too long ago for lights that I gift, giveaway, or for the kids lights. They work well too, you just loose some of the runtime. Upside is they are dirt cheap. I think if you stick to any Samsung, LG, Sony, Sanyo, Panasonic, and a few others I am forgetting, and you buy from a reputable seller, you will be more than happy.
Unprotected cells are better if you need higher current and they are shorter so they fit most flashlights.
Protected cells are longer so you need to check if they fit in your lights, but they are more foolproof because of shortcircuit and overdischarge protection. Their max. discharge current is limited by the protection circuit, often to less than the cell continuos discharge rating, so they can’t be used in high current flashlights like the Emissar (or any other light that would burn your pockets if turned on accidentaly)
The best cells for most flashlights are the Panasonic/Sanyo 18650GA and the Samsung 35E. The LG MJ1 is only slightly worse, so it’s a good choice if cheaper.
IMHO a good price/quality tradeoff for protected cells would be the protected MJ1 at Illumn if they fit your lights, you can get them at $6.50 + shipping. Zeroair tested their current limit and found it’s more like 7A than the 8A stated, but that’s enough for most lights.
You can get protected cells with a better current rating at Mtn Electronics or Liion Wholesale for about $2 more.
Edit: please don’t measure your current batteries with a metal caliper because it would shortcircuit them.