Think it is 3 lives per round, just had a go at the solo 4 vs 4 ranked queue.
Had a death match in that tiny arena with the lava terrain damage effect, we lost the first match, I died early on didn't know about the limited number of lives so charged into the ring, didn't help we lost a member right as the match countdown was starting.
The rest of the team won the second match I died slightly less early on, managed some assists.
Tie breaker match, once again died relatively early on managed some assists even a kill, near the end the last two members of the other team decided to sit in their spawn point and shoot down with ranged attacks, eventually the rest of the team managed to kill them in the spawn point.
All throughout the 3 rounds, kept getting the system message that I would be kicked for inactivity, if a player is dead and has no option to revive they should not be threatened with being kicked from a match, I could have understood if I was purposely avoiding reviving.
Should be some sort of way to force people out of their spawn points or prevent them from being able to attack/be attacked while in the spawn points.