Self discharging batteries. Feedback appreciated!

[xirrious]

I have a laser; 532nm, advertised as 1w but does more near .1w or 100mW, and the thing to note is the key lock tail cap security feature. No LED indicator. Now it takes a single 18650 so ~500mW pump diode, not sure what amperage an 808nm diode would use for 500mW, let's say 1.5, which is close as that figure matches real battery life using 3400mAh. Anyway so I thought it'd broken somehow when it didn't turn on one day, took me a minute to realize the battery was dead, so I replaced it and turned the key to the OFF position this time before putting it up. Still killed the battery. This is with the laser off and the key was tried off and on. Even while on it only connects two parts of a circuit together not complete it when the switch is off.

So is the problem simply somehow it completes a circuit with a small draw simply because the batteries drain when they whore their energy out in any possible way available such as a poorly made circuit?

OR is there something about DPSS lasers I clearly am not aware of? I've never had this problem with similar 532nm keyed lasers or any laser for that matter. Any info on why this is happening is appreciated. Don't tell me "cuz the tail caps on man," only actual articulate replies please.

Thanks! Pictures-

One of my 589nm, it's just soo se><y

 

[Marco Polo]

Are the cells protected? Perhaps there is some fault with the protection PCB.

Maybe the cell itself is at fault. What kind of battery is it? Is it an Ultrafire, or similar bad-quality cell? You mention 3400mAh, so that suggests Panasonic to me (a good brand) but we've all seen bad-quality cells (mis)labelled as 3400mAh.

Maybe see if you can measure any current draw from the battery with the laser powered off and key switch off. "Tailcap key switch" suggests something like a 301. Maybe there is some kind of current leakage through the switch mechanism.

Maybe the driver somehow allows current to leak through it although it is supposed to be "off".

 

[Cyparagon]

Use a DMM to meter the current when it's "off". If you don't have a DMM by now, you should be ashamed of yourself

 

[Pi R Squared]

Damn right, no business even owning a laser if you don't own a DMM. I would test both the current without the tail cap, and test the resistance of the tail cap by itself when turned off, Marco may be on to something there.

I have the same problem with a camera, its damn annoying to put new batteries in it (4 AA) and take a few photos and go to use it 10 days later only to find them drained.

Alan