Hey guys new to the forum and flashlight hobby, I just bought a trustfire tr-3t6 (yeah i know alot of people bash on this light for some reason) but anyways they say to use 3×18650 batteries for it. I searched online for 18650 and there seems to be many different ones, and by different i mean the amount of mAh. From my understanding all i know is that the 18650 or any rechargable lithium ion batteries can blow up. I tried to google the differences about these 18650’s and none of the websites seemed to answer my question. So my question is which mAh 18650 should i use? What does the different number mAh in the 18650 do? i see anything from 2200 mAh to 3100 mAh. Any information or help would be highly appreciated!
Higher mAh is longer runtime for the light.
Check the "Rechargeable Battery Reviews and Tests" section for information about specific batteries, there is a lot of battery reviews and also a summary.
Welcome to the madness, xoutlawx!
My opinionated summary:
18650 batteries come in protected and unprotected versions. Generally speaking, protected offers protection from overcharging, undercharging and reverse charging (which is important in a light that has 3 batteries in series like what I think yours is).
mAh ratings are sometimes true and sometimes bull. Use HKJ’s tests to figure out which are true and which aren’t.
There are lots of crap recycled (then re-wrapped) cells on ebay, so buyer beware.
You’ll probably get safety and quality if you go with a known manufacturer’s cell — Sanyo, Panasonic, LG… this isn’t an exhaustive list — that’s sold by a reputable place.
As budget ones go, lots of people (self included) seem to be happy with Xtar 2600s.
To get a little more runtime, Panasonic 3100 based cells (AW, Redilast, Kallies Kustoms, Keepower, Orbtronic, and a few others I’ve probably forgotten) offer good bang with a slightly higher buck. There are clear-wrapped Panasonic 3100s out there as well, and at the moment, they seem to be genuine, but as HKJ noted, these might be an attractive target for counterfeiting, just as Trustfires are.
Good luck!
Thanks for the link!
Thanks man, I have been sucked into the hobby & I only have a small collection at the moment. Jetbeam rrt0 xml, eagletac p20c2
, fenix ld10, olight t15, trustfire tr3t6 and a few d cell and aa maglites. 
Thank you sir this is the answer I’ve been hoping someone would be kind enough to tell me. Its so hard to get answers especially on candle power forums(some of them are stuck up high end flashlight hoarding folks). But anyways thanks that was really helpful
Welcome xoutlawx. Yea, over at C*F ask a question & it can tun into the “inquisition”!
Keith
Buy good quality batteries. Don’t buy cheap ones. Avoid Ultrafire/Trustfire/Crapfire 3000 + myahrse batteries. Protected batteries are safer for multicell lights.
For the love of God… Dont buy any, XXXXFire battery…
You can find one Sanyo 2600mha for less than 6$
Are protected batteries safe from reverse charging as well?
Every Lithium battery (except for 14 x Brentronics/Saft BB-2590’s) I have bought in the last two years has been made by AW. Probably have 60-70 of them in various sizes/capacities. Have not had one fail on me yet. Yes they cost a few bucks more but the quality and the peace of mind that comes with it is worth every penny.
Do i have to fully charge the AW18650’s before using/testing them?
I think that in your case, your light uses 3 18650 batteries in series so they need to be within a few hundreth’s of a volt (up to 1/10v difference) of each other to operate safely. You should charge all of them up before you use them and check the voltage. If one measures at 3.9v and another measures at 4.2v, you could have a problem.
In theory, they should be. But I wouldnt count on that.. And AW cells are heavily overpriced.
This is what I think about the AW, I dont know why some people still buy them if others brands are almost the same, like obtronic.
If you want to be sure, check the compare chart of HJK.
People buy AW batteries because they have great quality control and work very well. Generally, they use top grade Panasonic cells (are there any better ones?) and the protection circuit, if you buy the protected flavor, also works well. AW also makes IMR batteries that are unprotected for heavier loads. I have a mixture of both. One mans “heavily overpriced” is another mans “few bucks more”. Batteries are the biggest danger of any light and I don’t cut corners when it comes to batteries I have in my pocket every day. Ultimately, it’s your choice. Be safe.
HJK has a lot of battery reviews. He is a good source of information for them.
In my opinion the reason to buy AW is peace of mind without having to search the Internet and learn about batteries. He has a very good track record on his batteries: they are safe and has good performance (But not necessary the best performance).
For this you pay a premium.
But remember that there does exist fake AW batteries, i.e. either buy them directly from AW or from a dealer you trust!
For people that does search the Internet it is possible to get batteries that are just as safe and with same or better performance at a lower price, but the risk of getting unsafe low quality batteries does also exist.
Oops! It’s HKJ - not HJK. That’s the second time I’ve gotten that wrong. Sorry.
I may be wrong, but I’m afraid that even a perfectly sound protection circuit can’t prevent the reverse charging that takes place while the “inferior” battery’s voltage is still above 2.7V (the deep-discharge tripping level).