Liven up a new current friend (7)
I believe the answer is:
animate
'liven up' is the definition.
('animate' can be a synonym of 'liven up')
'a new current friend' is the wordplay.
'a new' becomes 'an' (I've seen this in other clues).
'current' becomes 'i' (symbol for electric current).
'friend' becomes 'mate' (mate is a kind of friend**).
'an'+'i'+'mate'='ANIMATE'
(Other definitions for animate that I've seen before include "Enliven, inject energy into" , "Invigorate; alive" , "Enliven, alive" , "Liven up" , "Inject life into, as with cartoon" .)