Full Charge Below 80 miles?

I have had my eGolf just over 3 weeks now. It was in service for about a week and just got it back with JX1 module replaced and a software update. Since getting it, I have noticed that the battery is showing as fully charged while the mile range keeps dropping. At first when showing as fully charged, it showed a range in the low 80s, but that range has continually declined and is now showing a range of just 67 miles at a full charge. Can this be due to cold temperatures (the high here today was around 17 degrees)? The decline in range when showing fully charged has seemed to correspond to the deep freeze we are currently experiencing in the Northeast.

I noticed something the other day that might explain this. After a full charge, I watched my regen dial during braking and noticed that the left hand indicator wasn't moving as far into the green charge range as normal. I also noticed that for that trip, my average consumption number was in the 2-3 range where I am normally safely around 4mpKwh. In turn, my "remaining range" indicator started dropping quickly. When I thought about this, it might make sense for this reason: If the batteries are completely full, the car can't use the energy gained from braking (because there is no where to put it!), because it isn't using that power, the average consumption level isn't as good. Because the remaining range is based on your driving style, I assume it must use your recent average consumption number to calculate range, and thus that drops too. I noticed that after I drove maybe 20 miles, the range + "distance drove since last charge" were back up in the 90 range. So I believe this is a temporary condition that happens when the battery is fully charged. Honestly, it seems the system could be a bit smarter about this, but this little quirk is the least of my concerns with the car!

Having said all that, I do believe I've seen reports of significant range hits with cold outdoor temps. Lots of people reported the most success by setting the car to "pre-warm" when you're plugged in at home before you start driving in the morning. Then the energy needed to keep the car warm is a lot less than if it was warming from 0 degrees while also powering the car!

<<<Lots of people reported the most success by setting the car to "pre-warm" when you're plugged in at home before you start driving in the morning<<<

I've seen that too, but unless you're going to have a range problem for the days driving, which is almost never my case, it doesn't seem to be worth the trouble. The heater for the seats and the car come on so fast that having a warm car at the ready isn't needed either

Ron

svento said:

I noticed something the other day that might explain this. After a full charge, I watched my regen dial during braking and noticed that the left hand indicator wasn't moving as far into the green charge range as normal. I also noticed that for that trip, my average consumption number was in the 2-3 range where I am normally safely around 4mpKwh. In turn, my "remaining range" indicator started dropping quickly. When I thought about this, it might make sense for this reason: If the batteries are completely full, the car can't use the energy gained from braking (because there is no where to put it!)
...
Lots of people reported the most success by setting the car to "pre-warm" when you're plugged in at home before you start driving in the morning. Then the energy needed to keep the car warm is a lot less than if it was warming from 0 degrees while also powering the car!

Click to expand...

You are correct about the lack of regen on a full battery. Even knowing this, recently I got a full charge at a winery on top of a hill, and upon coasting down the steep, twisty road in B mode was still taken by surprise when there was no braking of any kind until I recovered from :shock: It's just not something I've had happen enough to think ahead for it -- I rarely charge to 100% -- so I believe this, and the potential to forget to set the usual regen mode each time you start the car (or even just put it in park IIRC,) is giving the gremlins way too many tools to work with.

IMO, not only should the regen level be remembered always (and the other things another poster aptly compared to a pilot checklist,) there should be a high-current sink that regen braking energy can be discharged into when it can't go into the battery. Or, at the very least, friction braking should approximate the level that would happen otherwise, but I bet that would be much harder to implement consistently.

Finally, I keep my house cold and have been guilty of setting a higher than normal temperature for pre-trip warming... like 82 degrees. It's incredible how much of that leaks out when I open the doors to slot in my gear and self. Anyway, I almost always forget to set the cabin temp accordingly (as if I knew exactly what it was by then, anyway -- damn the engineers who thought an interior temp readout was TMI.) Thus, the AC comes on and cools the cabin down to 72.

Either that situation, or the opposite for people like Ron who (must be part polar bear* and) think the car warms up fast enough while you're in it, causes mpkwh to be lower at first, while the climate control is reaching the set level.

* No offense intended, Ron... if I did, please feel free to call me a parrot or other temperature-wuss creature of choice. Also, I do agree that the seats warm up quite quickly and on level 3 give a very worthy demonstration of the phrase, "in the hot seat."

I must say I haven't driven much, with the snow and all, but the few times I took it out in 20 degree weather, the car heated up very rapidly. I had all the vents opened to max and the fan and seats on max. The heat was pouring out. Also, while I haven't done it, it appears you can dial the temperature to 88 (hi) which should really pour out the heat right from the get go

As soon as the snow clears, I'll keep a closer eye on it, but I suspect for the few minutes it takes warms up the cabin, I won't need to do battery conditioning unless I'm planning a long trip

Ron