On Thu, 3 Dec 2009 11:41:14 -0000, tim.... wrote:

Trouble is, most clocks etc. seem to stop with voltage at about 1 - 1.2,
so
rechargeable cells at 1.2V... If a clock would run for a reasonable time
on
1.2V, hybrid cells would be needed to be practicable.

As it originally wasn't clear if the battery was flat or the clock broken I
tested the one I took out

it registered 0.7 volts (yes that surprised me as well)

They do vary. One clock pags out at about 1.1V but that cell will then run
another clock for 3 - 4 months.
My RF 'stat/prog. drops out at 1.4V so the 4 cells go in to a marked box
and are used for clocks.
--
Peter.
The head of a pin will hold more angels if
it's been flattened with an angel-grinder.