I have been thinking about buying a advanced flashlight and apparently the two popular battery types here are 18650 and CR123. Which is easiest to find? Do manufacturers like Duracell or Rayovac make 18650 cells? Do they come with the charger or do I have to buy that separately? Which would be the best value? How expensive are the batteries?
A good vape shop should carry decent 18650's. The closest one to me had nice LG brand 18650's (brown wrapper). However, you might want to verify whether the flashlight requires non-protected, protected, high discharge (amps), or even proprietary versions (like
some of the newer Olights and NiteCore's).
If you plan on using it every day or two, rechargeables are the way to go. If you keep one stored for emergencies, CR123's are a great option. Some flashlight's will take both, and some of those comes with an adapter so the CR123's don't rattle, or to allow CR123's with the proprietary battery design they made for their flashlights (i.e. NiteCore's P#i line - alhtough they use 21700's instead of 18650's). You might check to see if the manufacturer lists different outputs when using CR123's in their 18650 flashlight.
Generally speaking, I can pickup a pack of 12 CR123's directly from SF for about $25 before tax and shipping. That's less expensive than the 2 pack's of CR123's from Duracell, Energizer, and Streamlight at my local shops. They list a ten year storage life, and often have a "suggested use by" date printed on the battery.
A good unprotected 18650, (I would consider tbe brown LG I have just fine - rated 20A continuous discharge) should be prety inexpensive online, or at a vape shop that doesn't price gouge. Some reputable battery sites list ones for around $6, and it should last a number of years with daily use. However, some of the newer flashlights with higher lumen numbers might require "button top" cells, or the longer protected cells, or even cells with a higher Amp rating, i.e. Acebeam X10 requires 30A continuous for Turbo). Many times this is just a different branded flat top cell overwrapped with a protection circuit, charging adapter, and/or other wiring added on for specific flashlight designed for propietary batteries.
Keep in mind, that there are dangers with Li rechargeables, and you might need to pay more attention to your flashlight usage when using unprotected 18650's (or any Li rechargeable). For the record, you should use the same safe practices even if the 18650 comes with protection circuitry. I'd also NOT skimp on a good charger. However, if money's tight, some flashlights have USB charging built in (just remember not to do it when you are using the CR123's), until you can afford a good charger.
