Awesome, thanks! I got the keyboard used with my Mac, it worked perfectly for 6+ months with near to no light... and then suddenly gave me trouble. Battery would not charge enough anymore, even charging under direct sun would only hold for an hour or so, I ended up having my cell phone flash light atop the keyboard. Ordered the right battery, forced open the battery thing (what a dumb mechanism), and... it is at 100%. And so far so good - seems to like me again. :)
Now off to somehow improve general lighting here.