I've noticed lately with my 2014 C-Max Energi (27K miles) that the remaining battery percentage decreases overnight while sitting. I've suspected this for a while so started keeping closer track of it. Here's an example of what happened yesterday.
Drove to work in the morning and parked it. It had 82% of the charge remaining. Came out 8 hours later and still had 82%. Drove it to my next destination on EV mode and parked it with 72% charge remaining. It sat for approximately 14 hours overnight (unplugged) and when I got in this morning - only 65% charge remaining. The daytime high yesterday was 64 F and the overnight low was 54 F. I'm sure the battery may have heated up a little and the fan had to engage some but would it pull that much power?
I'm going to keep watching this to make sure I'm not losing my mind. I'm baffled as to why 8 hours of sitting during the day there is no loss of battery yet 14 hours overnight, I lose 10% of what is left.
any thoughts or ideas? I don't see any indication that anything is being left "on" (it doesn't seem you can "leave the lights on" with this car, anyway).
This is my first plug-in hybrid so I'm sure there are things about it that I do not yet know...