Here is the command for smcli to expand an existing Logical Drive. I had to mix documentation from Dell, IBM, and SANtricity to get a working command line. The ; at the end of the line is required. i just ran smcli localhost and pasted the below command.
This is not the same as add capacity in the GUI.
set logicaldrive["name or label of logical drive"] addCapacity=SizeinBytes;