We have a solar powered alarm clock which automatically synchronises with
the terrestrial time signal. The clock is marked 'PRECISION', 'SOLAR
POWER' and 'RADIO CONTROLLED'.

The display became faint and eventually it stopped working. I took a look
inside. There was an unmarked AA size battery (leaking blue liquid which I
cleaned up). I measured the battery's voltage which was 1.6V, well above
that of a normal rechargeable (1.2V?).

I presume the battery is the source of the problem. I tried replacing the
battery with both rechargeable and non-reachargeable AA ones, but the unit
still didn't work.

I suspect that the original battery was much more than 1.6V - maybe 3V? But
I can't find any references to
rechargeable AA-sized 3V batteries. Can anyone suggest where to get a
replacement battery (or other ideas)?

Cheers.