Some Li-ion chargers, when presented with a dead battery, will sit there, apparently doing nothing, when they're actually conditioning the battery with brief pulses, before starting main charge. The process may take minutes to hours.
I tested it and each cell is showing 3.6v
This young and nearly new looking genuine M18 battery was in my other garage on a Milwaukee torch unused for months. I went to use it this morning and it was completely discharged. Milwaukee charger won't recognise it so I'm trying this. Amps are steadily going down which would suggest it's accepting a charge?
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The battery status indicator still appears dead though.