Comment 9 for bug 496221

Hi, GNUbee40, I've managed to partially solve the issue. Open Configuration editor and go: apps → gnome-power-manager → thresholds and change the time values. "time_action" is the time remaining in seconds when it hibernates (or anything else u set it to do). This works for me:
time_action = 600
time_critical = 900
time_low = 1200

Or, if u want it to work according to the battery percentage remaining, go: apps → gnome-power-manager → general and untick "use_time_for_policy" and then set the values for percentage again in "thresholds".

However, it still doesn't solve the bug itself, so I believe ubuntu should come with default values like this until they manage to solve the problem.