With leading goalscorer Glen Murray injured, Phillips stepped up in his fourth play-off final to send Palace back to the top flight against Watford.
Phillips is on loan from Blackpool, where his contract expires imminently, and Holloway would happily sign the striker once again.
"I'll keep signing him until he's nearly 50 or 60, if he keeps putting the ball in the net," the Palace boss said.
"The difficult thing for Kev is living in a hotel once or twice a week because he doesn't need to move his family any more. That's what you lose; you lose that desire.
"So I don't train him every day. My lads accept that because they know what he does when he does turn up.
"It's his enthusiasm that he needs to keep. It's that little spark inside him, that jiggle. That's what I want to keep.
"It's your soul inside you. That little vibe when you get up in the morning. I've still got mine. Hopefully he's still got his.
"I can't wait to see him again and thank him for how well he's played for me."