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Discussion Starter #1
Ok....
When driving the Volt long distances you have three mode choices.
1. Normal which basically uses all your battery until it's gone and then turns on the generator.
2. Hold mode which holds your batt'ry at current level and turns on generator.
3. Mountain mode which uses up three-quarters of your battery and then turns on the generator. Or ...if you've used up all your battery and then you switch to Mountain mode the generator actually uses some of the power to recharge the battery ...from what I see about a quarter (I Know ...Less than 1/4) of a charge. And then just runs on generator and holds your battery at 1/4 charge.
So my thought was why didn't Chevy, in Mountain mode , allow you to use the generator to continue to bring the battery up to a full charge on long trips so that you could just run on pure battery for a while and then repeat?
Which brings me to my Title question... has anyone heard about some software hacking /Jail breaking for the Chevy Volt that would allow you to use different charge configurations then is programmed in the vehicle?
Lord knows Chevy is a not going to send us any software improvements for this vehicle since they gave up on the Volt.
 

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What would be more economical to do would be to get a 'slow depletion mode' which use the ICE at a constant speed. Then uses battery to help when more power is needed (small hills on highway). The way hold works is that is uses the electric to help stabilise the Ice but is refill what's taken after... Just an idea...

Envoyé de mon ONEPLUS A5010 en utilisant Tapatalk
 

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Two reasons - one technical and one political:
  1. It's less efficient to use the gas engine to charge the battery. This is also the reason Voltec II (2016 - 2019 Volts) use the gas generator to directly drive the transmission.
  2. If GM had done as you suggested, the Volt wouldn't qualify under either CARB or Federal rules as a PHEV. It would have been listed as a standard hybrid.
 

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The Volt has been around since Dec 2010. This has been tested. It takes more gas overall to propel the car with the gas generator AND run the gas engine at an even higher RPM to create excess energy to fill the battery all the way up.
 

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Re: #3: It seems to me that Mountain Mode was developed to allow the Gen 1 Volt to maintain performance under high power demand driving conditions, not to "recharge the battery." MM temporarily increases the "switch to gas" state of charge, establishing a larger buffer of "borrowable battery power" than is normally necessary for everyday range-extending driving conditions.

The Volt remains in Electric Mode when MM is selected if the SOC is above the MM-maintained level until the SOC drops to the modified "switch to gas" point. MM also includes a "feature" that enables the car to self-charge to the MM-maintained level if MM is engaged when the state of charge is below that level. This feature allows the driver to create this larger battery buffer while driving toward the mountains instead of requiring the driver to make a lengthy recharging stop.

Battery range is dependent on driving conditions... that’s why so many drivers use Hold Mode when cruising on the freeways, when gas mileage is good, and save the battery for slower speed suburban street stop-and-go driving.

If you charged your battery using Mountain Mode while driving down the highway and then switched to battery mode and continued down the highway running on MM-recharged battery power, your "gas mileage" would drop.

It takes a given amount of gas to MM-recharge a fully depleted battery to the MM-maintained level. At freeway speeds, you would get further down the road while driving in normal engine-is-running Extended Range Mode using that given amount of gas than by using that gas to recharge the battery and then driving on MM-recharged battery power.

On the other hand, in slower speed stop-and-go traffic, the same given amount of gas might get you further down the road while driving on MM-charged battery power than while driving on gas in normal engine-running Extended Range Mode.

The real question is, if you could use MM to fully recharge a fully depleted battery, how would you track Grid Electric Miles vs Non-Grid Battery Miles vs Engine is Running Miles? And would regen-powered miles have their own category, or would they be split three ways (i.e., obtained while MM was recharging vs while not recharging), or only two?
 

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The mountain mode also leaves about 2 bars from full charge to allow more room for regenerative braking on long descents. I'd battery is full, you can't benefit from that.
 

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The mountain mode also leaves about 2 bars from full charge to allow more room for regenerative braking on long descents. I'd battery is full, you can't benefit from that.
Using Mountain mode the Gen 2 Volt only charges to 2 bars from 0 bars (15 - 20% SOC.) The Gen 1 Volt charges the battery to 40% SOC using Mountain Mode.
 

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I vaguely recall a post about the engine starting when the hood is popped which also charges the battery. It was implied it kept running as long as it was open and didn't seem to matter the state of charge.

If the hood is popped while the vehicle is in drive does it also run the gas engine? I'm not saying to actually open the hood but if the hood switch had a bypass to make the car THINK it is open would that force a recharge similar to mountain mode but letting it run until a higher charge state?
 

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Common newbie idea and question. Thinking about it though, if you're going to fully charge the battery with the engine why bother having a plug-in? It would make more sense to have a regular hybrid or a gas car. Charging the battery up with the gas engine is the least efficient use of the fuel. The intent of mountain mode is building up a reserve to maintain momentum up a long steep grade. The intent of hold mode is saving the battery charge to use at a later portion of a long trip.
 

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Common newbie idea and question. Thinking about it though, if you're going to fully charge the battery with the engine why bother having a plug-in? It would make more sense to have a regular hybrid or a gas car. Charging the battery up with the gas engine is the least efficient use of the fuel...
If you could fully charge your fully depleted Gen 1 battery via Mountain Mode in ~40 minutes using only 1 gallon of gas, and you could then drive your Volt in stop-and-go traffic and on slower suburban streets for 40+ battery miles using that MM-recharged battery, rather than the less than 37 gas miles you might get driving the same car on the same routes using 1 gallon of gas with the engine running...

...and if you had no place to charge at home or at work (e.g., on street parking only, or you live on the fifth floor of an apartment building, or your electricity costs you $0.40/kWh) but you did most of your driving around town...

Wouldn’t you prefer to buy a car that you could drive around town on quiet battery power, even if you had no place to plug it into the wall?
 

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What would be more economical to do would be to get a 'slow depletion mode' which use the ICE at a constant speed. Then uses battery to help when more power is needed (small hills on highway). The way hold works is that is uses the electric to help stabilise the Ice but is refill what's taken after... Just an idea...

Envoyé de mon ONEPLUS A5010 en utilisant Tapatalk
Hold mode is pretty "slippery" in that it allows the car to dip into the battery to increase efficiency when you hit a hill on the highway or need to pass someone. The problem is that eventually, the car will try to replace some of those electrons and that "forced regen" is a big efficiency hit.

If GM were to continue developing Votec, I could imagine an endurance mode where the car analyzes the navigation data on longer trips and meters out the battery power so as to keep the ICE running in its most efficient range. Sadly, we won't see that if all the indications of GM's abandonment of Votlec prove accurate.

For now, I continue to reset the Hold point on longer trips to avoid forced regen and if my Voltstats are accurate, it results in a measurable mileage gain.
 

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[*]It's less efficient to use the gas engine to charge the battery. This is also the reason Voltec II (2016 - 2019 Volts) use the gas generator to directly drive the transmission.
[*] If GM had done as you suggested, the Volt wouldn't qualify under either CARB or Federal rules as a PHEV. It would have been listed as a standard hybrid.
[/LIST]
Great points.

Charging the battery from the generator would be beyond inefficient and would put the car in super-pollution/hyper-expense mode. It's more inefficient/expensive than charging the battery from a wall charger. (for most people) It's also more inefficient/expensive than driving the car directly from the generator. (Due to charging losses.) To do this would be equivalent to stacking dollar bills on the roof and lighting them on fire as we drive down the road.

I think this is a normal thing to contemplate and I thought about it when I first started driving the car. The GOM and energy display seems to have a physiological effect on people and I find myself being emotionally "tugged" by it at times. It makes us want the battery bars to be "full" and instills a bit of panic when the battery "miles" go to zero; even though there may be plenty of gas. The way the display is laid out, it seems natural that we would want to trade gas miles for battery miles in the display to "fill up" those missing bars.
 

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An easy way to think about the Volt's energy usage is the battery holds enough charge for an equivalent one gallon of gas (a little more with Gen 2) so charging the battery from zero is the same as putting one gallon of gas in the tank. The difference (an benefit of the Voltec) is it only costs about half the cost for electricity that the price of gas so over time you save a lot of money, especially if you take advantage of free charging at some public or work charging stations.

On long trips on the highway, if you use the battery alone, you would only be able to go about 30'ish miles on a charge compared to about 40'ish mpg on gas, so it make sense to use the engine on long highway trips and save the electrons for city driving. I usually can get about 60 miles on a charge in city driving. That's way Chevy added the Hold mode in 2013. Back int he day, we early adopters used mountain mode as sort of a Hold mode to save some charge for city driving after a long trip to Disney World.

If gas prices ever go back to where they were in 2008, everyone's Volt would go way up in value since not a lot of cars sold give you what the Volt does (no range anxiety). Oil producers miraculously keep finding more and more oil so that may not happen for a while.
 

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It would be an interesting comparison. It might seem less efficient to use the engine to recharge but engines are usually most efficient when fully loaded. Letting it keep full load and just splitting that load between charging and propulsion for interstate driving may end up being slightly more efficient than the gas side just being used for propulsion alone.

Anyone ever paid attention their gas MPG when the car is recharging in mountain mode? If you only lose 2-3 mpg but gain 10 miles of electric out of that same gallon it seems like an overall gain. If it drops into the high 20's or low 30's then forget it. That's just a waste.
 

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It would be an interesting comparison. It might seem less efficient to use the engine to recharge but engines are usually most efficient when fully loaded. Letting it keep full load and just splitting that load between charging and propulsion for interstate driving may end up being slightly more efficient than the gas side just being used for propulsion alone.

Anyone ever paid attention their gas MPG when the car is recharging in mountain mode? If you only lose 2-3 mpg but gain 10 miles of electric out of that same gallon it seems like an overall gain. If it drops into the high 20's or low 30's then forget it. That's just a waste.
That's assuming a constant rpm (engine loading vs. not). If the engine isn't loading the rpm will drop (I believe I read 1500 rpm) or it will turn off all together (going down hill or coasting up to a stop light). If the engine loading is higher, the rpm will increase. What seems to happen in MM is that the engine turns at a consistent higher rpm to maximum charge the battery as quick as possible up to limit set. You would have to carefully take note of miles driven under MM while charging battery then immediately switch to EV and back again then take note of mileage vs. reported gasoline usage at end of trip (easier to do with Gen1 with it's larger battery charging capability). Easier to do as a two man job, one to drive one to record as you are flipping between the different drive modes and even then it may be more complex than that as this is a simplified way to get MM mileage and the computers might not make it that simple..
 

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I was thinking just use the energy meter as a rough calculator. Deplete the battery then switch to mountain mode on a fixed loop. Once you consume 1-gallon of gas switch back to hold and drive until the battery is empty again. Note your total distance traveled.

Now drive in straight hold mode on the same loop. Note your miles driven when the energy meter shows another gallon used.

It's been so long since I've looked at that energy meter I can't remember got detailed it is. Did it show gas used in tenths of a gallon or hundredths?
 

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If I couldn't plug in at home, I don't think I would even consider a plug in car.
Many share that thinking, which is likely one of the reasons why GM chose not to provide the Volt with the ability to fully recharge the battery via self-charging, a feature that may have enabled them to market the Volt as an electric car for central city dwellers and the host of others who have no at-home charging capabilities.

It would be foolish to purchase an electric vehicle without considering where you could refuel it. On the other hand, Nissan says their Note e-Power electric car, a plug-less series hybrid using the Gen 1 Volt range-extending concept (a gas generator fuels the motor and recharges the battery) was the best-selling registered non-minicar in Japan for the first half of 2018.
 

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Many share that thinking, which is likely one of the reasons why GM chose not to provide the Volt with the ability to fully recharge the battery via self-charging, a feature that may have enabled them to market the Volt as an electric car for central city dwellers and the host of others who have no at-home charging capabilities.

It would be foolish to purchase an electric vehicle without considering where you could refuel it. On the other hand, Nissan says their Note e-Power electric car, a plug-less series hybrid using the Gen 1 Volt range-extending concept (a gas generator fuels the motor and recharges the battery) was the best-selling registered non-minicar in Japan for the first half of 2018.
Sort of re-enforces my point. If plugging in is impractical, it makes more sense to buy an ICE or hybrid vehicle.
 

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Irrespective of any efficiency arguments, it may be possible to charge the battery to full with the engine running by making the car think that the hood is popped. When the hood is popped the engine charges the battery ( even though the manual says it doesn’t). Not sure how the car knows the hood is popped, assume some interlock or switch near the latch is involved. Let us know if you are able to do this without driving with the hood latch released ( dangerous), would be interesting to know.
 
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