Where do you have the LVC set?

Five minutes with an Eflite 46 on a 13x8APC with judicious throttle control is roughly where I'd expect the battery to be at the LVC point.

Why do you say "Plenty of battery left"? What does that mean?
Assuming a 5S1P set up you were more than likely out of 'juice'. As a matter of fact I'm surprised you got that far, I would have expected no more than 3 minutes with the set up shown here (lots of open ends).