# Identify the nominal voltage of your battery. In the case of the Black & Decker 20V MAX Lithium-Ion Battery, this should be around 20V.
# Using a variable voltage power supply, manually charge the battery at a voltage slightly higher than its nominal voltage. The idea is to boost the battery’s nominal voltage closer to its desired value.
# Continue charging for around 10-15 minutes. This should be enough to bring up the battery to a level where your drill power supplies can recognize and charge it again.
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