i charged up a lipo (unbalanced) and the readings said one cell was a little over 4.26v and the other cell was about 3.88v. the automatic shut off on the passport ultra is 4.26v. the total of the two cells was about 8.4v, which i'm assuming it cut off at. however, i thought the charger would have cut off at the 4.26v the one cell had reached, preventing damage to that cell.