Band's crew is full of energy and on the way (7)
I believe the answer is:
roadies
'band's crew' is the definition.
(I've seen this in another clue)
'is full of energy and on the way' is the wordplay.
'full of' is an insertion indicator.
'energy' becomes 'e' (physics symbol as in E=mco).
'and' says to put letters next to each other.
'on the way' becomes 'road' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'is' enclosing 'e' is 'ies'.
'ies' after 'road' is 'ROADIES'.
Can you help me to learn more?
(Other definitions for roadies that I've seen before include "Band tour crew" , "Transport managers" , "Pop group's tour assistants" , "They handle the equipment for entertainers" .)