Minn Kota On-Board Precision Charger MK-550 PCL 5 Bank x 10 AMP LI Optimized Charger [1835500]On Board Precision Charger MK 550 PCL 5 Bank x 10 AMP LI Optimized Charger Longer run times. Shorter charge times. That's the precision difference that keeps anglers on the water longer and puts more fish in the boat. Now, the next generation of this legendary line of chargers has been optimized for 12 volt lithium (LiFePO4) batteries. Precision chargers feature battery type selection by the bank, which now includes charge curves specially formulated