Odd behavior with my L2D/batteries

[jxwhadley]

Last night, I had my Fenix L2D set on medium, standing on its tail end. It had been there for a few minutes when from across the room, I heard it fall over. :thinking: I went over, picked it up and the rubber clicky had swollen up and caused the light to topple! I turned it off and took out the batteries and they were only a little warm but barely. They were low on power though, as I put the batteries back in, turned it on and waited to see if this would happen again. Turbo wasn't any brighter than high and it looked like the beam was getting dimmer. The rubber clicky was swelling again so I turned the light off. I'm now charging the batteries back up in a LaCrosse BC-900U ('test' mode, where it'll charge, discharge, then charge them back up again). The batteries are (2) AA Energizer 2500 mAh and are pretty new yet; they've only been charged 2 or 3 times. The charger didn't reject them; if a battery is bad, the battery terminal readout will still say 'null' after you've put the battery in.
Does this sound familiar to anyone? Any danger here maybe?

Thanks in advance!

 

[Stereodude]

I've seen other threads on this. The batteries are venting some, which is causing the tailcap to swell.

 

[mighty82]

If you use the batteries till they are empty in the L2D, and they are not perfectly matched. One will empty out before the other, get reverse charged, and vent. That battery is now useless, and should not be charged, this can be dangerous . This have happened to a lot of people, and it's the reason I only use matched pairs of eneloops in my L2D.