John Rumm wrote in message ...
Dave Plowman wrote:

They all seem to use the same sized cells - called sub C size. So the only
way to increase capacity is to increase the voltage - you can't parallel
these types of cells.

The capacity of the sub c cells can vary by quite a margin however.
Cheap and nasty ones as found it the budget tools may only be good for
1.2Ah. The better end of the market can offer twice that capacity not to
mention closer cell matching, and lower internal resistance, better
cycle life and discharge characteristics.

Not all battery packs are equal - and to an extent you get what you pay
for.

Got it in one.

Cheap battery tools equals cheap battery and cheap charger. Either the
charger fails to charge or boils the battery, sooner or later. More
expensive tools tend to work until battery fatigue.

Either way though buying a complete new machine is cheaper than
replacing parts.