On the 07 Prius...driving like a normal car, the HV battery would usually be in a partially depleted state, unless you've just got off an expressway... then you'd have a "green" battery... The Prime, with drive it like a car driving in HV mode, seems to keep the HV portion of the battery full. Some of that may be a difference between the Prime and the old car, some of it may just be the way I drive. But for my last trip of the day, with no EV miles left, where I know I'm headed for time for a full charge... my strategy is to deplete the HV portion of the battery as much as possible.. You would not do this on a non-plugin prius, because it would take gas on a cold engine to recharge the battery the next drive, but on a plugin... it seems that you'd want to end up home with as little charge as possible (saving gas by driving as EV in HV mode) since in reality there is only one battery and the wall charger will charge it up with "cheap" electricity. To be sure, not depleted enough that the ICE kicks on to charge it though. My routes back to my house end in a few miles of street driving after expressway driving... and it's fairly easy to run it off the battery on 35mph streets leading to my house. Does this make sense? or am I missing a hidden cost here?
That's how I would plan it. I even think the Ford Energi's will use the battery more to run it down once they've learned were home is.
A possible hidden cost is from dipping deep into the HV reserve frequently leading to more battery degradation. In the older generation Prii we have most information about, battery degradation was faster for people who lived in the mountains. This was attributed to frequent deep excursions into the HV reserve. I mention this to say that you should not be entirely confident that Toyota is protecting you against your worse instincts to try and game the system.
Just to clarify, the extra range that the Energi design (called EV+) uses doesn't come from digging deeper into the pack. Rather it lets the driver use ALL of the HV portion of the pack without starting the ICE if they are in the EV+ zone (work, home, etc). If you run out of that, it starts the ICE. As the OP said, this works very well for the plug-in Ford owners who can use wall power to recharge that HV portion deficit but the hybrid model owners will still need to make up the deficit with the ICE on the next start. That's fine if the next start is the next morning or a period long enough for the ICE to cool off so a warmup cycle is needed anyways.
Yeah but I think @Oniki meant the HV portion. Just like the regular Prius, you don't want to go into 2, 3 or 4 bars too often.
my 07 prius battery lasted 196k miles. still going strong when i traded the car. i did not baby that battery and i liked ev driving on it on a couple legs of my routes. i dont expect the prime to perform worse than 10 year old technology
