I have a digital LCD clock, a giveaway by NTT from a trade fair, that still works with the same single Maxell AA battery since 1998. The battery quality must have been amazing at the time, or the clock uses almost no power. I honestly don't know how that's possible. :D
Ine the same way designers discussed above try and big dick their designs, clocks when through some EE big dicking on trying to minimize battery usage. Same thing with LCDs.
They got them to really low power usage. Some of the ones today would basically last your whole life on a single button cell.
