Is there a way to reference one variable with another? Preferably by name.

Another way to do the same thing would be to make your file like this:

     - Battery Status -
Voltage:          [%1]V
Temperature:  [%2]C

Set up a 2d array of char and when you see %, send the nth row to the LCD. Of course, you'll need to populate the array appropriately, which effectively means you're replicating the mapping functionality.