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Does anyone know of a way to reprogram the mountain mode to fully charge the battery instead of stopping at 1/2 charge? I would like the option because I have discovered that if I leave town and deplete the battery on the interstate, I get better economy if the engine is fully utilized while running instead of doing the up & down thing on a depleted battery. With 1 mile left on the battery, I switch to mountain mode. After about 35 miles at 75 mph, the battery is at 1/2 charge and the engine is only matching the need for power, I switch to "Normal" mode and run off the battery for the next 16-18 miles. At 1 mile left on the battery, I switch back to the mountain mode again for the recharge. Example of economy: I left for a round trip on Thanksgiving day with 37 miles range on the battery and 180 miles in the gas tank. I drove 244 miles round trip. When I plugged it in on return, I had 2 miles on the battery, and 47 miles left in the gas tank. Before I used the Mountain/Normal switch, the actual combined battery and tank range was always real close to the gauge estimate. I would have had to stop at a gas station before I got back.
 

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I don't know of a way to do what you want.But why would you? Between charging from the wall and using MM, MM is less efficient (costs more).
 

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Does anyone know of a way to reprogram the mountain mode to fully charge the battery instead of stopping at 1/2 charge? I would like the option because I have discovered that if I leave town and deplete the battery on the interstate, I get better economy if the engine is fully utilized while running instead of doing the up & down thing on a depleted battery.
It doesn't work that way.

And I'd like to see some numbers showing that you get better economy that way because ... I don't. I get about 38 "MPG" from the fuel burned to charge up the battery from "depleted" to the 14 miles it puts on before shutting off in my driveway, and the "up and down thing" gets me about mid 40s MPG in the summer @ 60ish MPH and about 40 in the depths of winter with the snow tires on. That's a HUGE improvement the other direction than you're asserting.
 

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Does anyone know of a way to reprogram the mountain mode to fully charge the battery instead of stopping at 1/2 charge?
Mountain Mode was developed so the Gen 1 Volt could maintain performance while driving up roads of the type that have "pass" in the name (e.g., the Siskiyou Pass, the Snoqualmie Pass). In effect, switching into MM increases the "switch to gas" state of charge from a no bar soc to a ~4 bar soc so you have an increased buffer of borrowable power to use for high power demand conditions in Extended Range Mode. MM’s "recharging feature" allows you to build this battery buffer quickly while driving toward the area where it would be needed, rather than requiring you to stop and plug in the recharge before heading into the mountains.

Many would like to see a "self-charging" feature that could fully recharge the battery. The car could then be marketed as a self-charging electric car to drivers who lived in apartments or had on-street parking and had no charging facilities. GM has chosen not to do this, but then, it could be that frequent "fast charging" the Volt battery would significantly shorten battery life (I’m not sure if this topic has ever been discussed).

You haven’t really provided us with much information regarding your performance when using MM. Estimated ranges at the start and at the end of a long trip are highly unreliable indicators of anything. At the end of your 244 mile trip, what numbers were showing on the energy usage display for Electric miles/kWh Used and Gas miles/Gas used?
 

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I don't know of a way to do what you want.But why would you? Between charging from the wall and using MM, MM is less efficient (costs more).
Although one might think that using Mountain Mode to recharge the Gen 1 battery during a trip would make the trip more expensive, it’s easy to forget that MM charges the battery only to the ~4 bar level. If you arrive home with the battery still charged to that 4 bar level, you’ve added about $1.08 to your trip’s fuel costs for the gas to put that charge into the battery, and now you only need to add 6 bars for a full charge, saving you $0.58 in recharging costs, a difference of about $0.50.

The numbers: for a 2011/2012 Volt, MM recharging uses 0.36 gallons of gas, slightly more for later models, which, at $3/gallon, is only $1.08. The "from the wall" cost of those ~4 bars of power is, at $0.12/kWh, about $.58.

The OP has chosen to recharge via MM, then drive on that power, then recharge via MM, then drive on that power during the trip instead of just driving in Extended Range Mode. The question then is whether or not one of the two methods uses more gas.

Seems to me the OP has mentioned something about MM recharging that is easily overlooked. When driving in Extended Range Mode, the engine is turned off and on as needed to minimize fuel use while meeting the power needs of the motor. When MM is recharging the battery, the engine is running full out until the battery is charged to the MM-maintained level. This provides better fuel economy during the recharging of the battery. The end result is that, if MM could fully recharge the 2011/2012 battery, it would use ~0.94 gallons of gas to do so. Later models would undoubtedly also use just under 1 gallon to do so.

One could then drive 35-38 battery powered miles (depending on model year) in a Gen 1 using a battery that was fully recharged via MM by using ~1 gallon of gas in the generator, or about the same distance you could drive in normal Extended Range Mode using 1 gallon of gas in a car rated at 37 mpg.

IOW, if you use MM to recharge the battery, and then use that MM-recharged battery power to drive "Gas" miles (and then, if desired, repeat the cycle as you drive), your total Gas Miles is more or less where it should be for the quantity of gas used, and so is your MPGcs "gas mileage."

Of course, driving conditions are variable, and the conditions actually experienced will determine if using MM to cycle "engine running" miles with "MM-battery powered miles" or just normal Extended Range Mode driving produces the better trip gas mileage.

Note: the results would be confusing with a 2011/2012 Volt because those models count MM-recharged battery powered distances as "Electric" miles (without increasing the kWh Used), which then deflates the total gas miles to produce lousy gas mileage numbers but inflates the total electric miles to produce great miles/kWh numbers.
 

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No one pays 12 cents / KwH when all the electrical costs , including distribution (which you pay per KwH too) is accounted for.
my power bill.jpg

I pay 7.63¢ per KWH. There is a $25 "base charge" on the bill, but I don't figure that into my cost per mile calculations. That base charge was there before I was even aware what a Chevy Volt was. I am figuring only what charging the car adds to my bill. As the weather has warmed up my cost per mile has gone down from 2.5¢ to 2¢.
 
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