Venting incident on AAA alkaline

At least I believe that's what I experienced.

I had a Duracell AAA in my Maratac stainless steel light and as I thought the battery was running down and needed to be replaced I started to unscrew the head. But the head was so tight that I could hardly twist it off. This wasn't normal for this light and actually I had lubricated the o-ring with Krytox about a week before. Anyway, I finally wrestled the head off, at which point there was a distinct "pop" sound.

First time I've experienced this in an alkaline. I suppose venting is not uncommon as alkalines leak all the time, but I guess users don't experience anything because the lights aren't airtight.

Alkalines makes noise all the time, once I had an energizer sitting on the table and it started chirping away loudly like a cicada, emitting this low pitched hissing sound that went on for over a minute. During this time I grabbed it with an insulated pair of tongs and carried it out in a parts tray and rested in the garage. The next day I went to check it emptied some of its contents all over the tray, which the leading edge had begin to crystallize.

NIMH are known to vent hydrogen, most of my "pop" experience have occurred from using eneloops. Oddly enough they haven't leaked. I'm not exactly sure how the gas is vented if the cylinder itself is not compromised.

Interesting.

I figured it was pretty common, just haven't experienced it much myself.