If its a Lithium, then you need a special charger. I'm not sure what tech
they use but even nickel metal hydrides need a constant current and when
fully charged just a pulse of very low current if they stay in the charger
to keep them from overheating. Most batteries seem to charge better as
single cells as capacities vary as the age and one cell being low gets
reverse charged by the others in use in series.
Brian

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"John Rumm" wrote in message
o.uk...
On 21/10/2020 18:01, pdworley wrote:
What polarity should I use to charge the cordless battery on my Black &
Decker 9.6v drill. I lost the adapter that came with it. I have a multi
volt adapter with a polarity switch. What polarity should I set it on?
Thanks

Why not test the voltage on the connector with a multimeter and copy that?


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Cheers,

John.

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