In article ,
says...
My Bosch cordless 14.4v drill/driver has provided about 2 years fairly
heavy use and lately it is noticeable the batteries charge life is
getting much shorter and i assume will shortly need replacing. I
haven't shopped around much but noticed the cost of these are around
£70 - is this right? It doesn't add up to me, pay £140 for replacement
and spare when i could get a new one with 2 batteries for around the
same price. Is this something us cordless users have to put up with,
or are there cheaper outlets - i've looked in Screwfix but couldn't
find them?

You might check out

http://www.geocities.com/powerbatteries/powertool.html

--
Mike