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I have started to create the "Voltipedia," an entry-level guide for people who are thinking about buying, or who have recently bought, a used Volt. It is in very rough shape at the moment, and it requires a lot of fact-checking and new content. I'm hoping that members of this group will contribute to it. Perhaps someday it will be a web site. For now it's just a Google Doc. Anyone with this link can comment on it, and I will incorporate suggestions as best I can.

 

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I have started to create the "Voltipedia," an entry-level guide for people who are thinking about buying, or who have recently bought, a used Volt. It is in very rough shape at the moment, and it requires a lot of fact-checking and new content. I'm hoping that members of this group will contribute to it. Perhaps someday it will be a web site. For now it's just a Google Doc. Anyone with this link can comment on it, and I will incorporate suggestions as best I can.

You might distinguish between different generations?

In the category of why not to get a Volt, the fact that they're discontinued, it's getting harder to find parts, it's getting harder to find technicians, there's a lot more to go wrong than either a pure ICE or pure BEV so on average they're more expensive over time, and if there's a serious battery issue the value of the car can immediately plummet to zero all seem like they should be mentioned.
 

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I agree with niccolo. It’s very important to distinguish between the Gen 1 and the Gen 2 Volts. I say this in part because your opening paragraph on How It Works is simply wrong. In a Gen 2 Volt, the gasoline engine CAN power the car’s drivetrain directly by itself. That’s a significant difference between the generations - when the battery is depleted, the Gen 1 continues to be propelled by its electric motor, using battery power for acceleration and generator output for cruising, and the Gen 2 becomes a gas hybrid car using an automobile engine for propulsion.
 

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... when the battery is depleted, the Gen 1 continues to be propelled by its electric motor, using battery power for acceleration and generator output for cruising, and the Gen 2 becomes a gas hybrid car using an automobile engine for propulsion.
Well, gen1 has both serial and parallel modes once battery is depleted. Parallel (power split) is Prius-like in operation and does result in some engine torque going to the wheels (just less than gen2 can do).
 

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Well, gen1 has both serial and parallel modes once battery is depleted. Parallel (power split) is Prius-like in operation and does result in some engine torque going to the wheels (just less than gen2 can do).
I thought Gen1 never sent torque to the wheels, maybe power directly to the electric motor driving the wheels, rather than through the battery?

Gen2 can send torque to the wheels, but the battery is still critical, i.e. at most it's driving like a hybrid where both the battery, via a motor, and engine, are contributing torque.
 

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AFAIK, the Gen 1 petrol engine torque does mechanically make it to the wheels under certain conditions. It's not the preferred mode until highway speeds are reached though.
 

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I thought Gen1 never sent torque to the wheels, maybe power directly to the electric motor driving the wheels, rather than through the battery?

Gen2 can send torque to the wheels, but the battery is still critical, i.e. at most it's driving like a hybrid where both the battery, via a motor, and engine, are contributing torque.
Common misconception (that refuses to die, even on enthusiast forums). Power-split mode happens above 36mph whenever large torque isn't demanded. So pretty much all the time, unless you're hill climbing of accelerating heavily, when it will shift to series mode (and then back to parallel once demand reduces). If you're cruising on a 40mph road or 70mph highway, you're in power-split. Some of the engine torque is consumed by the generator, but some is also physically transmitted through the generator's shaft into the ring gear. Just in gen1, this alone cannot drive the car, you need MGB also providing reaction torque in this mode for the car to work. So the engine alone can never physically drive the car, but it can (and very often does) physically assist.
 

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Discussion Starter · #8 ·
I agree with niccolo. It’s very important to distinguish between the Gen 1 and the Gen 2 Volts. I say this in part because your opening paragraph on How It Works is simply wrong. In a Gen 2 Volt, the gasoline engine CAN power the car’s drivetrain directly by itself. That’s a significant difference between the generations - when the battery is depleted, the Gen 1 continues to be propelled by its electric motor, using battery power for acceleration and generator output for cruising, and the Gen 2 becomes a gas hybrid car using an automobile engine for propulsion.
Thanks. I can't remember where I got my original info but like you said, it was wrong. I have rewritten the intro and referred people to Wikipedia for the technical details.
 

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Discussion Starter · #9 ·
You might distinguish between different generations?

In the category of why not to get a Volt, the fact that they're discontinued, it's getting harder to find parts, it's getting harder to find technicians, there's a lot more to go wrong than either a pure ICE or pure BEV so on average they're more expensive over time, and if there's a serious battery issue the value of the car can immediately plummet to zero all seem like they should be mentioned.
Thanks, Niccolo. I have pointed out the difference between Gen1 and Gen2 in the "Shopping" section. Are there other places where the differences need to be called out? I don't even own a Gen2 yet (I'll get it Saturday) and I'll probably never own a Gen1, so it's hard for me to know exactly where Gen1 and Gen2 experiences diverge.

I've added a couple notes on the "why not to." Do you have a reference for the total lifetime cost of ownership vs. other cars?
 

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Dave, I sent you a PM!
 

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Well, gen1 has both serial and parallel modes once battery is depleted. Parallel (power split) is Prius-like in operation and does result in some engine torque going to the wheels (just less than gen2 can do).
I agree the Gen 1 Volt has serial and parallel modes when the car is in Charge Sustaining Mode (in Hold or Mountain Mode or fully depleted battery) but my understanding is the parallel mode is engaged to improve efficiency (i.e., better "gas mileage"). Power split configuration provides no performance improvement. If you could flip a switch to prevent the system from using 2-motor configuration, you could drive a Gen 1 Volt hundreds of non-stop "electric" miles before the generator ran out of fuel. When you are extending the range at highway speeds in a Gen 2 Volt, you are using an automobile engine as the primary, if not sole, source of propulsion.

My point is that there is a significant difference between the Gen 1 and Gen 2 Volts. The Gen 1 Volt can obtain full performance using only the larger electric motor MGB, which makes it possible to "extend the range" using electric propulsion only (with fuel provided by the battery and the generator output). The Gen 2 Volt is engineered to blend the operation of the 2 electric motors in Electric Mode, and thus when the range is being extended, the system uses the ICE to fill the role of the second motor, adding an automobile engine component to the propulsion configuration. The Gen 1 Volt uses the battery as the source of the fuel that enables the motor to accelerate the car when the range is being extended. The Gen 2 Volt uses the gas tank as the source of the fuel that enables the ICE to accelerate the car when the range is being extended.
 

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I thought Gen1 never sent torque to the wheels, maybe power directly to the electric motor driving the wheels, rather than through the battery?

Gen2 can send torque to the wheels, but the battery is still critical, i.e. at most it's driving like a hybrid where both the battery, via a motor, and engine, are contributing torque.
AFAIK, the Gen 1 petrol engine torque does mechanically make it to the wheels under certain conditions. It's not the preferred mode until highway speeds are reached though.
Thanks. I can't remember where I got my original info but like you said, it was wrong. I have rewritten the intro and referred people to Wikipedia for the technical details.
Details here: Text description for each; pictures in articles; etc.

Voltec drive unit has four basic modes of operation
 

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Discussion Starter · #13 ·
Details here: Text description for each; pictures in articles; etc.

Voltec drive unit has four basic modes of operation
Thanks ... added a link to this thread in the Voltipedia.
 
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