i bought two “crap lights” on clearance, will probably pick a few more up to stash away… they have half decent aspherical lenses and a aluminum screw in plate for the emitter and driver… lens moves not the emitter.
naturally, the “plot line” initially was to use them to learn to swap out the press in driver and emitter, but… you know, cant resist PLAYING with them, you know?
they are 3-D bodies… i went 4-c, and the amps went up, still a ho hum minor improvement for a very underdriven crap-light… but… since i REALLY didnt care if i BLEW the thing? i pulled the aluminum chunk out with driver and emitter… and started with 2xAA and my DMM on amp reading… then added a AA… then added another, lol…
when i finally got brave with it, i tried TWO unprotected 18650’s in series? 8 volts… this netted me 1600ma on “hi”, which was a little more like it…
i had to “hold” a little piece of copper between the two 650’s, to get the to run in series… unprotected flat tops? flat top is a mis-nomer… more like a recessed top, lol…
whats the quickest, easiest, go-to method to plop those 2 650’s into a TUBE to get them runnign the light to see what its like on 1600ma? I dont wanna get TOO intto fabbing for it, since the orginal (and still best, lol) plan was to replace the driver and pill…
A little magnet will be fine as long as it cannot short onto the flashlight body. Some will suggest a solder blob done very quickly to the positive end so as to not get to much heat into the cell.
I have soldered a small “button” of solder on many of my flat-top cells to work in some lights, and would work in series too. ( though i refrain from using un-protected cells in series for saftey reasons.
For safeties sake, center the magnet on + pole and apply superglue around the periphery. Don't try to put glue under the magnet. will not stick (for long).
i only use a little one bay 18650 charger that came with my one light… it had a protected cell came with it. Generic little one bay charger…
i took 2 unprotected out of another device, and use themon that little charger… i have to use a magnet to get connection, lol. shrugs I just watch with my DMM in parallel and when the voltage hits 4.1 or 4.2, i take them off.
now for the cringe?
I saw 2 LiFePO4 18500’s in a pack at the home improvement store. I wanted to try them in series in a 2-c cell body? they worked… but charging? again to the little generic one bay charger… and a couple neodymium magnets and a little spring…
when the voltage gets 4.0 or 4.1, i take them off.
I dont know, i am sitting there watching the voltage, and none of the cells ever gets anywhere near warm. They never really heat up.
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when i fooled around trying the 2 unprotected in series? I made sure both were within a couple 1/100ths of a volt of each other.
yeah, when i get the 2 18650’s in series build going? i will ick up 2 protected to dedicate to that light… but for just now working on stuff? it works okay, i guess.
It would be a VERY good idea to use PROTECTED lithium batterys in series.