I use 18650 batteries with my Cree T6 torches. The batteries I have came with the torches and I have had no problems or concerns with them.
However, when looking on Amazon with a view to buying some more there are so many different brands claiming all sorts of different capacities and an equal number of negative reviews stating they are fakes, dangerous or do not hold the capacity claimed etc; etc; etc.
How does one know if one is buying a genuine and safe battery?
Apparently, according to one review, the maximum capacity a 18650 battery can hold is around 3400 mAH. Two of my batteries branded as 'Ultrafire' are stamped as having 4200 mAH and 4800 mAH. They seem to charge fine without getting hot and last quite a while but how do I know if they are safe?
------------- Hypercamp Alaska
Vango Force 10 mk3
Vango F10 Helium 1
Coleman Cobra Pro 3
Coleman Cobra 2
Naturehike Star River 2
Eureka! Solitaire
Dutch army goretex bivvy bag
I received two blue ones like those with my first torch I bought off Amazon and have had no problems. However, when I checked them out last night before writing this thread I realised all the black print had rubbed off them, so I haven't a clue what make or capacity they are. I would have thought the print shouldn't rub off batteries.
Another issue is that some of them are described as 'flat top' and are apparently used for vaping. I think the Samsung ones mentioned above may be flat tops. Does that make any difference in a torch or would a flat top not contact properly?
No the 18650 Lithium ion cell is around 25% larger than a AA (aka LR6) cell, also the voltage of the 18650 is just slightly more than double that of the AA at 3.6v.
No doubt as time moves on, the 18650 will become the new AA, although the new kid on the block is the 2170 Lithium ion cell that Tesla are churning out in there millions at the new Gigafactory.
The 2170 is around double the size of the AA, so larger again than the 18650.
The 2170 offers higher energy density than the 18650, but also at a lower cost to the tune of 30%.
I am predicting that the 2170 cell will take over the world, and will remain in that position for at least 20 years.
You need a button top for your Cree. As you said the flat tops are for vaping.
------------- Hypercamp Alaska
Vango Force 10 mk3
Vango F10 Helium 1
Coleman Cobra Pro 3
Coleman Cobra 2
Naturehike Star River 2
Eureka! Solitaire
Dutch army goretex bivvy bag
Quote: Originally posted by Francais on 30/4/2017
No the 18650 Lithium ion cell is around 25% larger than a AA (aka LR6) cell, also the voltage of the 18650 is just slightly more than double that of the AA at 3.6v.
No doubt as time moves on, the 18650 will become the new AA, although the new kid on the block is the 2170 Lithium ion cell that Tesla are churning out in there millions at the new Gigafactory.
The 2170 is around double the size of the AA, so larger again than the 18650.
The 2170 offers higher energy density than the 18650, but also at a lower cost to the tune of 30%.
I am predicting that the 2170 cell will take over the world, and will remain in that position for at least 20 years.
Does that mean I am now going to have to buy new torches and battery chargers or will the 2170 battery fit? I have just bought a new torch which is why I was looking at batteries
The original 18650's were, and I think still are, made by Ultrafire in China.
There are however a number of Chinese companies making cheap copies and selling them on Amazon Marketplace, these are the dangerous ones.
Quote: Originally posted by Bernie47 on 30/4/2017
The original 18650's were, and I think still are, made by Ultrafire in China.
There are however a number of Chinese companies making cheap copies and selling them on Amazon Marketplace, these are the dangerous ones.
Yes, that's the problem...no way of knowing. One reviewer said if it has 'fire' in the name it is probably a fake and another said if it claims higher than 3400 mAH it is probably a fake...mine have both
It's the same with the Cree XML-T6 torches. They come from many different makers with different prices and all are slightly different in some way. Of the 5 XML-T6 torches I have, the switches on 3 of them started playing up after awhile so I am guessing those are the fake ones.
I guess it doesn't matter if they are fake providing they don't burst into flames and that can't be happening very often or they wouldn't be allowed in the country.