Electronic device's only lines disconnected by discharge (5,4)
I believe the answer is:
solar cell
'electronic device's' is the definition.
'solar cell' can be an answer for 'device's' (solar cell is a kind of device). I am not sure about the 'electronic' bit.
'only lines disconnected by discharge' is the wordplay.
I cannot really understand how this works, but
'lines' could be 'll' (two abbreviations for line) and 'll' is located in the answer.
'discharge' could be 'arc' (electrical discharge) and 'arc' is present in the answer.
'only' could be 'sole' (synonyms) and 'sole' is present in the leftover letters.
No letters remain.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for solar cell that I've seen before include "Producer of electricity from sunlight" , "source of power" , "source of electricity" , "Device converting sunlight to power" , "Converter of sunlight to electric power" .)