Not being an expert on batteries (definition: "ex" meaning "has-been" and "spurt" meaning "a little drip under pressure"), I have used 'em a lot. I've found that if I'm using a battery to run machinery, such as a portable cassette recorder, such devices tend to suck the batteries dry a lot quicker than a flashlight would. But when they no longer have enough juice to run the recorder, they still have enough to power a flashlight, at least for awhile—or actuate a battery tester, pushing the needle at least partway into the green, if not all the way up like a fresh battery.

FWIW.

Don Firth