My cells got hot before 2/6 cells died on me over a month ago. I still didn't get my replacement from SMC btw. I think the new batch of IB cells are only good for like 10 charges until it becomes unstable. I used the remaining cells on my 4cell brushless, and those are starting to vent at 5amps. I discharge my cells to 1V/cell and finish it on a equalizer to 0.9V. I hear there might be a new batch, and hope those are more stable. Until then, I'm happy with my EPs.