Drove away and broke down over a period of time (9)

'drove away' is the definition.
('dispel' can be a synonym of 'drive away')

'broke down over a period of time' is the wordplay.
'broke down' becomes 'died' (dying is a kind of breaking down).
'over' indicates putting letters inside.
'a period of time' becomes 'spell' (spell is a kind of period of time).
'died' going around 'spell' is 'DISPELLED'.

'and' acts as a link.