EC 8064 then EC 8515 at Gatwick
Barcelona → London → Lisbon
Timetable, London time
15:00EC 8064 from Barcelona at the gate
09:20EC 8515 to Lisbon leaves the gate
18 h 20 apart on the timetable, overnight
EC 8515 leaves 18 h 20 after EC 8064 arrives on the timetable: more than half a day, so not a connection we count.