I have a 44 mile round-trip work commute with extended hilly uphill/down hill sections. On a fully charged battery, I can complete the commute with roughly 10 miles of EV range remaining at the end, using normal mode throughout. The commute is 50% city (where some of the hills occur, usually traffic free) and highway (flat). I think my current approach maximizes fuel economy and efficiency, but I am wondering if ending up with 20-25% remaining charge each day is good for the battery longer term. I am tempted to engage HV mode, not on the highway (which I would for longer highway trips) but before going up hills and using normal mode when not going up hills. Despite excellent regenerative braking- the car tends to lose more EV miles uphill then it gains going downhill. However, for some reason I am reluctant to do this. I could of course use HV mode on the highway- which would conserve charge- but also decrease overall mileage. Of course the same is true using HV mode for up hill. What are your thoughts on this? Also, if there is remaining EV charge, is normal mode generally running battery only- except perhaps when AC or heat is running? I am guessing if it is very hot or cold-I will be forced into HV mode during this commute.