I understand what the function of a joule thief is - to allow a device like an LED to be powered by a dying battery. But recently I've been wondering what is the purpose of one exactly?
Isn't it possible to substitute a larger number of old batteries for a certain number of fresh ones? For example, if I needed a 3V power source, I could use 2 fresh AA batteries, or also 8 old ones that provide 0.375V each, right?
The only benefit I can think of that a joule thief would provide is that it allows the power source to be much smaller. A single AA battery with a joule thief can fit in a pocket flashlight easily, while 4 old AAs can't. But I would think there must be more of a benefit than this?
Isn't it possible to substitute a larger number of old batteries for a certain number of fresh ones? For example, if I needed a 3V power source, I could use 2 fresh AA batteries, or also 8 old ones that provide 0.375V each, right?
The only benefit I can think of that a joule thief would provide is that it allows the power source to be much smaller. A single AA battery with a joule thief can fit in a pocket flashlight easily, while 4 old AAs can't. But I would think there must be more of a benefit than this?