On Sun, 22 Oct 2017 21:07:22 +0100, "Ian Field"
wrote:

All my 18650s were rescued from discarded laptop packs - if I get any duds,
there's no point complaining to anyone.

I have a small collection of such batteries. The problem is that the
spot welded + terminal is flat and is missing the "button top" used in
most removable 18650 cells. I had to buy a few magnetic "button tops"
which work well enough, but are easily lost or misplaced:
https://www.ebay.com/itm/282578704173
My testing, using a West Mountain Radio CBA-II discharge tester,
showed that the cells market 2200 ma-hr delivered 2000 ma-hr at 1.5A.
Good enough.

The 3W Tesco headlamp uses one, but my biggest application is my e
cigarette. That's been in service well over 5yrs and I've only had to swap
out a couple of battery sets.

Between the eCigarettes, eBikes, LED lighting enthusiasts, power
tools, and radio geeks, it's a wonder that one can find 18650 cells.

The one that came with the Tesco unit is only 1800mAh - I get a lot more
running time from salvaged cells.

I recently bought a few of the lowest priced 18650 on eBay. Garbage
in, lumens out. These were suppose to be 5800 and 5000 ma-hr but
delivered 1000 and 880 ma-hr:
http://802.11junk.com/jeffl/battery-tests/18650.jpg
After about 10 charge/discharge cycles, the 5000 ma-hr cell is showing
signs impending failure.



--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558