Discharges current that's even (7)
I believe the answer is:
acquits
'discharges' is the definition.
('acquit' can be a synonym of 'discharge')
'current that's even' is the wordplay.
'current' becomes 'ac' (alternating current).
'that's even' becomes 'quits' (as in 'call it quits').
'ac'+'quits'='ACQUITS'
(Other definitions for acquits that I've seen before include "Clears" , "Pronounces not guilty" , "Finds not guilty and discharges" .)