an interesting forum here and no doubt there are many others,

https://www.quora.com/What-is-the-maximum-capacity-of-a-18650-battery 

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Fenix currently have a 3,500mAh 18650, which is a genuine capacity.

It's not cheap, though.

If eBay has a 5,000mAh 18650 and it's £2, then it's going to be junk.

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Although directed at Vapes/Ecigs, a chap called "Mooch" has some very good, detailed information.

In short, anything good for an ecig is more than adequate for a Torch/lamp. The current requirements of those things are, well, batshit crazy.

I'm currently using Samsung 30Q's. Not particularly cheap, but very, very good. If you're buying on ebay, then use the sellers Torchy (big_f_d_d) or Ecolux only. Most other sellers are peddling over-exaggerated or recycled cells.

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Panasonic and Sanyo are now same manufacturer.

High capacity means a lower possible maximum discharge rate.

A lot of other high quality Li Ion cells are above manufacturer re-branded.

Although still expensive they are not as bad as they could be due to high manufacture rate.

Sanyo UR18650ZY 2600mAh cells are now available at a low cost which makes JunkFire brands not worth bothering with.

Fasttech are selling them for $7.56 USD for a pack of 2, but they unprotected. A lot of torches though will go out before the voltage drops below the point where damage could occur, and a good dedicated charger will not overcharge them.

Later high capacity or high discharge cells are double that price.

The Sanyo and Panasonic cells on offer are unlabelled being Original Equipment Manufacturer (OEM), although Panasonic do offer retail wrapped as well.

Issue with the latest ultra high discharge is that the protection PCBs currently fitted to protected cells would not support the max discharge rate of the cell, so basically only useful to equipment manufacturers.
I tried 4 of these in my cheap eBay 'silly output claim' 6 LED torch and trashed the PCB.

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Although directed at Vapes/Ecigs, a chap called "Mooch" has some very good, detailed information.

In short, anything good for an ecig is more than adequate for a Torch/lamp. The current requirements of those things are, well, batshit crazy.

I'm currently using Samsung 30Q's. Not particularly cheap, but very, very good. If you're buying on ebay, then use the sellers Torchy (big_f_d_d) or Ecolux only. Most other sellers are peddling over-exaggerated or recycled cells.

Ecolux is a good bloke, recommended.

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I recently broke up the powerpack from an old laptop for its cells;they're unbranded, purple wrap and marked made in Japan.They seem to take a charge OK off my charger (an i4), should I consider using them or should I ditch them?:flowers:

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Fenix currently have a 3,500mAh 18650, which is a genuine capacity.

It's not cheap, though.

If eBay has a 5,000mAh 18650 and it's £2, then it's going to be junk.

ive seen 9000mAh ultrafire on ebay ..how I did laugh!

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I recently broke up the powerpack from an old laptop for its cells;they're unbranded, purple wrap and marked made in Japan.They seem to take a charge OK off my charger (an i4), should I consider using them or should I ditch them?:flowers:

Be wary, and monitor them. Any unusual heating or smells, then dispose of them.

Chances they are an ICR (LiCo) type, and as such, less suited to high discharge rates. Pop me a picture of the writing on the wrapper, and I'll dig out some specs for you. I'd be honest, for the money (under £15) and peace of mind, I'd buy decent, new ones. Samsung 30Q's or 32E's. These are an INR (LiMn) type, and suited far better for high discharges, with decent capacity.

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I kept checking them for heating up when they were on the charger but they behaved on that score. Here's a pic:

[photo]108153[/photo]

I'm quite happy to ditch them if they won't do well for lights since I didn't pay anything for them, but I thought I'd ask here...

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They are 2.45A constant current discharge. A single XM-L driven properly will want more than they can supply. They are indeed and ICR type of cell, most don't get above 5A or so, but these are particularly low, and likely worse given the age and use (laptop) they have had.

I'd recycle them to be honest.

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Thanks for the info. I don't know the exact age of the laptop they came from but it was several years old, so I probably will ditch them given this.

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