Purcell's in-close deflection at 9:25 of the third came shortly after the Lightning killed off a short-handed situation.
Ondrej Palat, Tom Pyatt and Steven Stamkos also scored for Tampa Bay, which improved to 12-1 when leading after the first period. Stamkos scored his 21st goal this season into an empty net with 3 seconds to play.
Maxime Talbot and Claude Giroux had goals as Philadelphia fell to 0-11 when trailing entering the second period.
Flyers defenseman Kimmo Timonen played in his 1,000th NHL game on his 38th birthday. He is the 282nd NHL player, and sixth from Finland, to reach the milestone.
Pyatt put the Lightning up 2-1 after skating down the slot and redirecting Tyler Johnson's pass past Ilya Bryzgalov with 2:57 left in the first.
Giroux got the Flyers even at 2 from the left circle at 15:21 of the second.
Tampa Bay took a 1-0 lead when Palat scored from the low right circle 6:38 into the game. The rookie scored his first NHL goal in Saturday night's 4-1 victory over the Carolina Hurricanes.
Talbot tied it at 1 at 13:55 of the first. The center made a nifty move to get past two Lightning defenders and then slip a backhander past Anders Lindback. Jakub Voracek hit the post with 2 seconds remaining in the period.
Philadelphia's Matt Read hit the crossbar 6 minutes into the third.
NOTES: 39 players that have reached 1,000 NHL games played spent at least part of their career with the Flyers. ... Johnson has a goal and two assists over his first three NHL games. He was recalled March 14 from Syracuse of the AHL. ... Tampa Bay D Keith Aulie stopped a 22-game point drought with an assist on Purcell's goal.