In an illustrative embodiment, a direct current (DC) fast charger (DCFC) controller unit includes a controller. The controller includes a processor and computer-readable media. The computer-readable media is configured to store computer-executable instructions configured to cause the processor to: receive a maximum charge time duration to charge at least one battery to a desired state of charge responsive to an increased efficiency charge mode being enabled; determine an amount of energy used in a plurality of charge cycles for charging the at least one battery to the desired state of charge with charge time durations no longer than the maximum charge time duration; select a charge cycle for charging the at least one battery to the desired state of charge with a lowest amount of energy used; and cause the at least one battery to be charged with the selected charge cycle.