When does ICE drive the wheels

[saghost]

We don't get all in a twit about using the CS mode in our Volt. When this car was new in March of 2011 we would get 40 to 41 mpg when driving 70mph in CS mode.I suppose that some of this driving is with the engine clutched up to assist the motor, but I sure can't tell. This year we get between 42 and 46 mpg all the time in CS mode. That is awesome. I will bet that only the Prius and the Jetta diesel do better. I guess our engine is getting broken in now. We drive all week electrically but do about 100 miles in CS mode commuting to and from our cottage on weekends.

Actually, when you consider that diesel has 10% more energy per gallon, and the way newer diesels are handicapped by emissions controls, you're neck and neck with TDIs on the highway... (I averaged 49.8 mpg over six years and 85k miles in an earlier TDI (2003 Jetta 5-speed) - 15% lighter, with barely over half the power.)

I've been noticing an improving trend, too - though changing driving habits make it hard to quantify. With 4100 gas miles now (8600 total,) I got 46 EV miles and 47 MPGcs from a ~200 mile round trip simply by following the (mostly 55, occasionally 65) speed limit. I think the part in the manual about not needing a break-in is more like 'there's no way to perform one, so don't worry about it.' it also makes me think the early first oil change discussed in another thread (from MT's oil analysis) might not be a bad idea.

[kj7]

This is mistaken. All 288 cells, 96 parallel triplets arranged in series, are charged and discharged together at all times. The capacity/degradation thing is about how much you charge them. The Volt never pushes the battery past ~85% charged, and never discharges it below 15% charged (the engine comes on somewhere around 22%, and it is unusual to get the pack much below that point.)

Since battery wear and tear almost entirely occurs at the upper and lower ends of the charge and at high temps, the combination of the limited window and thermal management keep the battery from wearing down for a long time.

I'm still waiting to see as far as opening the window to keep range goes - Frank Weber (line manager/chief engineer for a lot of the Volt development) made a statement in about 2009 that GM had to provide the same range at end of life ad at the beginning, which (possibly with some unofficial comments from GM) has been interpreted by many here to mean GM will open the window as the battery degrades. I still think it is a rather foolish idea on an EREV (better a battery with 10 miles left than one that failed totally do to range extension,) and am waiting to see if GM did it in the production cars. As well designed and tested as the Volt is, it'll likely be a long wait.

Thanks so much for the informative reply. Much appreciated. I obviously had a fundamental misunderstanding.

[banadictaustin]

I think It's also wise to add studded tires to your car when expecting ice, You can bring the car back into the right lane by simply pointing the wheels.