In article ,
William Sommerwerck wrote:
Just to add, it's sometimes cheaper to buy a different make of
battery that may be on offer and rob it of its cells to fix another.

This is not generally a good idea. Replacing the bad cells in one
battery with new, good cells, is likely to cause cell reversal during
operation. You should generally replace all the cells.

Well, yes. I wasn't suggesting otherwise. The majority of cordless tools
use sub-C sizes of different types and capacities - and of course number
according to the voltage. If you can buy one on special offer it might be
able to supply a set of cells to replace those in the faulty unit at a
lower cost than buying individual tagged replacement cells. I've done just
this a few times. For example, with the move to LI cells some are selling
off their NiMH cells at discount. Same with NiCads.

It's also useful to have some way of measuring each cell's capacity while
discharging it, so you can roughly match the cells' capacities.

Usually on the battery case or tool spec if not the individual cells.

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*The more I learn about women, the more I love my car

Dave Plowman London SW
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