Video Cameras and Batteries

I have two digital cameras: One old one that can't record sound and one bigger one that can record sound but still looks not-so-great in terms of quality and expends AA batteries like shotgun shells.

It'll do this thing where it quickly takes a new pair of AA batteries and within 15 minutes of use (at most) insists that these batteries are out of power. I take the batteries out for a while, put them back in, and they're full of power again according to the camera. This process repeats until the batteries actually are out of power, which doesn't take long.

Why does my camera do this? And is there a way I can modify my camera so I can plug it into an outlet instead?

That's just what they start doing. My old reject of a camera does the same thing.  No, you can't modify it, but if you really want you can just turn off and disable anything that'd eat up battery life (sound effects, the screen etc). I recommend upgrading to a more recent camera with a rechargeable battery.

Also, certain models of Powershot are known to eat through batteries really fast. It's supposedly a defect in the battery contacts. If you have one you're SOL.

A battery's voltage decreases as it discharges, and this is how a device guesses the capacity of a "dumb" battery. When you remove the battery it will "heal" up a little bit as it stabilizes chemically inside after discharging stops, meaning you'll get a slightly higher voltage again when reconnecting it.

I'd just get a camera that has its own rechargeable li-ion battery instead. Or just get a new phone. It's hard to find an android phone that can't record at least 1280x720 nowadays.

Wobbly mobile phone video can eat my poo.

A battery's voltage decreases as it discharges, and this is how a device guesses the capacity of a "dumb" battery. When you remove the battery it will "heal" up a little bit as it stabilizes chemically inside after discharging stops, meaning you'll get a slightly higher voltage again when reconnecting it.

I'd just get a camera that has its own rechargeable li-ion battery instead. Or just get a new phone. It's hard to find an android phone that can't record at least 1280x720 nowadays.

I always shake my batteries around, they last about 1/3 longer when I do.