change the battery in the light when it dies...
Well, the whole idea was to avoid ever changing the batteries again, since i got sick of recharging them every month.
Once a year is kinda neither here, nor there in that regard...
Ideally, i would have gone for nuclear power - they make tritium lights of that brightness and size that would last for decades, but it would cost $150 apiece.
As a matter of fact, trying to reproduce such a light for cheap was what started the whole project years ago.
so we're going to need a bigger battery
Sounds like it.
As a matter of fact, these LiSOCl2 cells are actually rather cheap (1/100th of the nuclear option), have minimal self-discharge, and the right kind of capacity.
I should be able to get 4-5 years out of an AA one even without the uC tricks.
And a 1/2AA one makes the thing only double the size of LIR2032 version, without sides of the disc sticking out - a cute little brick.
That with some tricks Fungus suggested might get me the same 4-5 years.
All in all, thanks for pointing these out.