Understanding Prime Reported MPG With EV Mode Capacity

in my pip, the car tries to retain most of the wall charge at the level it is when you hit hv. has that changed?

 

It takes a while to see how that %EV - trip distance - trip time or Drive Monitor 2 (in the gen 4) gauge works.
the time is the amount of the the car is ON (it doesn't matter if the car is moving or not)
The %EV is another anomaly. It's hard to understand how the computer calculates the %.
As soon as the engine starts that gauge goes from 100% EV to 99% EV in seconds and drops quickly from there, than slowly leveling out. The distance just mirrors the trip odometer. It's not intuitive at all.

 

Isn't that just 'percentage of time engine not running'?

 

There's EV mode and then there's EV Driving. Two different things. EV Mode is when you are using EV exclusively. When you're using HV, the ICE will turn on and off as needed. Going up a hill, ICE on, going down a hill, ICE off. Long flat area at moderate speed, ICE off, stop at a light, ICE off. That's where the EV Driving Ratio is coming from.

For the Prime, I have my EV capacity set to percentages not range. If you put it in HV mode and you have a full charge it will tend to use EV Driving more often at least initially because it has the spare battery power. This gives you better mileage. When we did a long trip, once the EV battery got down to 85% it seemed to stop using the extra power and stabilized.

If you use both EV and HV mode in the same trip, the trip stats seem to give an inflated MPG because it doesn't seem to take into account the time spent in EV mode and doesn't differentiate between EV driving in HV mode and pure EV mode.

 

There a lot of methods for getting more EV percentage while in HV mode. With No traffic driving sessions, if you can stay in the Hybrid System Monitor (screens) EV range while in HV mode (really slow speeds especially going up an incline - 35 Amps max for Gen4 according to DrPrius ) the engine will stay off much longer and shut down much quicker when it does automatically switch on.
MPG isn't the only metric that plays into HV modes efficiency, but along with distance driven and percentage of engine on time the efficiency is easier to get closer to reel life calculation of the Primes efficiency in HV mode.
Is there EV Auto mode in the Gen 5 as well?

The screenshot in post #1 didn't make a lot of sense to me without knowing how you're driving while testing.
I was wondering why on 50 MPG with the other indicators 10 miles in half an hour and 75% EV.

 

I suspect we are of a similar mindset (Gods help both of us) because I've tried a lot of the same things!

If you have a full charge, you will definitely get a higher MPG in HV mode as it draws down the battery to 85% and it stabilizes. So you might get 60 instead of 55 or something like that.

If you run in EV then click over to HV (or run out of charge and it clicks over automatically), it will give a wildly wrong MPG because it will count the entire trip, including the part you spent in EV range. Usually that ends up being 99mpg, which is as high as it goes.

There is. I haven't played with it, but from other people's reports, it remains almost completely on EV. I'll run a few days in that mode to check it out!

 

So a question: let's assume you are going to do a trip that goes well above the EV range, and do not plan to recharge; and that at the beginning and most of the trip you will drive on highways, at speed (a few hundred miles), and then arrive in a city where you will do city driving - then, is the best way to do this trip to put the car in HV mode until you reach the city, to preserve the EV range for city driving? I think that would be my approach, but curious for more knowledgeable people to weigh in.

 

The European version also has 'Predictive EV Drive' which plans when to use battery charge along a route. Works when in Auto EV/HV mode and you have a navigation route set, if enabled. Presumably lets the car plot to save charge for later, and maybe use it up sooner?

 

It may be because of the 20 trips. On the Gen 4 it seems to hold pretty close to the soc on one trip. I think it has to be looked at on each trip. 35% loss over 20 trips is 1.75% per trip average. Using 11 kwh battery capacity that’s about .19 kwh loss per trip average, not much. Probably within the range of error of turning off and on and what the car sees as soc each cycle is my guess.

 

Except going up known hills with known descent to recharge, I leave it in ev mode. It has a lot of zip, even berated gen 4 Prime, in ev up the hill. Then save that for city driving later.
Ford had an ev now and ev later selection, don’t need to think too much about what it means.

 

I've noticed our Prime doing that too. It switched modes on me once 2 years ago just as a cop drove by in the other direction. I think that was the first time I noticed, and it was shocking. - Just a few days ago on out way to market, it switched on the A/C. I asked the misses if she turned it on and she said no, I commented that the car must have wanted the A/C on and couldn't wait for us, so it did it its self.

thinking about losses, if watching close enough, it might take at least a few months of history data before it can be noticed, but I've seen the Prime reset it's estimates after it gets turned off, sometimes noticeably on the next On press, espeically if counting on remaing charge to get to destination before engine switches on.

I don't know how EV Auto works either. I really should at least switch it on a few times so I can compare how it behaves with my driving style with what I've seen while driving HV the last two winters and EV almost exclusively for the first couple of years, except for trips 100 miles or longer. If a trip was under 100 miles or so I'd plan in advance where to stop and charge, than see if I could actually make the route as planned.
plugshare.com
free to use, add a charger to their list with a pic if you've taken on and / or comment on chargers if broken or blocked

That sounds really interesting to me. I'd suspect the route planner is either a subscription feature or only available in the upper trims or trim. I've been toying with learning how to grade and incline, since I have my choide of 6 ways to get out of my neighborhood and all of them have a steep grade between 1 and 2 tenths of a mile before I get out onto the rolling downhjll in one direction and a slight incline for 2 miles the other direction, with another mile (3 in total) of a steep incline before I can get onto a wavy flat.

That is how I always at least begin longer trips. Sometimes I've been known to forget to swttch out of EV after stopping while on a long trip and not notice until we are out or EV miles, the misses has done that a few times too. Switching on Charge Mode if only for a few miles just to get some EV range back into the pack, Sometimes it will get used right up and other times it will build into a decent EV range.

Now I understand at least a little bit better, I've never tried to force engine on and especially not in near 100 F temps, when I'm always trying to lower the traction pack temps in anyway I can think up. A./C helps to keep the engine on longer and so does the defroster.

 

The only thing I know about is Predictive Efficient Drive, which I believe requires the navigation package, and will start to learn your regular routes and do things like start applying braking early so you maximize regeneration when coming up to a stop sign. I haven't tried this at all and don't have the nav package because Android Auto is so much better and free. The traffic jam assist also requires the nav package and I could never figure out how to turn it on during the month I had nav active.

 

We've got nav in our 2017 Prime Plus (base model). The misses has her phone paired to the car so she gets hands free calls (really loud and I don't know if there's a way to turn the volume of calls lower). I think that is how the nav got to it's current state casue I still have the original nav micro USB card. The nav works fine as far as I'm concerned and the audible directions are nice on long trips, but I never count of the cars nav alone. I always save the route to my phone and have misses do the same (most of the time). Ya just never know these days and my phone cellular service is real slow when I'm not near any wifi, or I'm just spoiled.

Two hours after posting above I found the cars phone call volume slider right on the MFD right in front of my face. But I was parked when the phone call paired with the car as I drove up to pick the misses up and she was on a call. It was nice to finally turn that damned volume down.