Charge new batteries. It's not necessary to charge over 12 hours when first used. When a device powered by batteries is purchased, sellers will usually tell us the batteries must first be charged 12 hours before using.Actually, this is unnecessary.harge new batteries. It's not necessary to charge over 12 hours when first used. When a device powered by batteries is purchased, sellers will usually tell us the batteries must first be charged 12 hours before using.