Electric vehicles (EVs), their emissions, and future viability

[oilhammer]

The Volt is a plug-in hybrid. There were C-maxes that were like that, and there are Prius models like that, and there are a bunch more I cannot think of right now. They typically have an extra "fuel" door in the left front fender ahead of the driver's door. May have even been a Fusion like that.

In the coming years, the badging of "hybrid" is likely to fade away, as it will sort of become a normal thing. The new Audi A7 is like that. It is a mild hybrid, but it is pretty transparent as to its operation, and has no badges to denote this. Kind of like things like "fuel injection" and "overdrive" used to be common badges affixed to cars when that was a "new" thing.

The thing I find interesting as that the new Sienna minivan will be sold as ONLY a hybrid, which makes me wonder if it will have a badge on it or not. Toyota decades ago said that within 10 years (it was 1996 at the time) they'd have a hybrid version of every model they sold, and in 20 years, they would ONLY be selling hybrids. Well 2006 came and went, and now 2016 came and went... still hasn't happened. I think they've as of yet been unable to keep the costs under control to be competitive. The hybrid option on the Corolla adds $4k to its base price. Although it does claim a ~10 MPG improvement.... making it about what my 20 year old ALH does. Not sure if that means the hybrid version is great or the non-hybrid version is abysmal.

 

[AntonLargiader]

FWIW the Volt is pure EV until the battery runs down. It sounds like the Pacifica is close... if you go "well past 50%" power demand the ICE will kick in, but that you can do pretty normal driving without hitting that. However it would be a bummer if you can't drive at freeway speed on battery only. That article makes it sound like that tipping point is a little bit under 80 MPH. The local dealer is supposed to let us know when there's one available for a test drive, but they are in pretty short supply.

That said, if you're going to have an ICE drivetrain then it's really not the end of the world for it to run now and then. The whole point of having it is that the overall drivetrain is designed to make good use of it.

 

[IndigoBlueWagon]

The whole point of having it is that the overall drivetrain is designed to make good use of it.

This is where you get off track. The whole point of an EV is to build a vehicle that doesn't require ICE of any kind. Hence the name. ICE merely makes up for deficiencies in battery capability.

My understanding is the ICE in a Volt never directly propels the car, although there seems to be some debate about this. That's what I see as a difference between the definition of EV vs. Hybrid, at least as Wiki describes it.

 

[oilhammer]

The myth of the Volt has been debunked. They have a direct mechanical linkage to the wheels when the engine is running and you are driving down the highway. It is NOT like a diesel-electric locomotive, which do not have any direct mechanical linkage (because there simply isn't a feasible way to make a transmission work for that sort of thing).

There is a youtube video about it somewhere, as well as several automotive magazine articles. Not sure where the misinformation started, though, but it was pretty common early on until finally someone actually took one apart. Not sure if GM leaked the wrong information accidentally or what.

 

[SilverGhost]

The myth of the Volt has been debunked. They have a direct mechanical linkage to the wheels when the engine is running and you are driving down the highway. It is NOT like a diesel-electric locomotive, which do not have any direct mechanical linkage (because there simply isn't a feasible way to make a transmission work for that sort of thing).

There is a youtube video about it somewhere, as well as several automotive magazine articles. Not sure where the misinformation started, though, but it was pretty common early on until finally someone actually took one apart. Not sure if GM leaked the wrong information accidentally or what.

But if I understand correctly - a Volt has no transmission. It can be directly coupled to the wheels (vs a diesel locomotive) but has no gearing beyond what is provided for the electric motors. So it needs the motor to get moving and to back up, but can use the engine at hiway speeds if needed. It also can start the engine and just run as a genset.

I was just talking to one of our GM techs that gets all of the Volts and Bolts.

Jason

 

[oilhammer]

But there is a direct-to-the-wheels engagement of the crankshaft for cruising down the road. I didn't think it was a fixed ratio, though, but maybe it is.

 

[bl00tdi]

This is where you get off track. The whole point of an EV is to build a vehicle that doesn't require ICE of any kind. Hence the name. ICE merely makes up for deficiencies in battery capability.



My understanding is the ICE in a Volt never directly propels the car, although there seems to be some debate about this. That's what I see as a difference between the definition of EV vs. Hybrid, at least as Wiki describes it.

An EV is an EV based on its operation, not its range. It's obviously not a pure EV, but it operates as one so long as its battery has charge remaining, hence range-extended EV.

 

[turbobrick240]

Yeah, there is a direct mechanical linkage via planetary gears of the Volt's ICE to the transaxle. I believe it is single speed and only used at higher speeds. It's a PHEV, no doubt about it. It is both an EV and an ICEV. But I suspect most Volt owners do the majority of their driving in pure electric mode.

 

[IndigoBlueWagon]

An EV is an EV based on its operation, not its range. It's obviously not a pure EV, but it operates as one so long as its battery has charge remaining, hence range-extended EV.

Based on these definitions the BMW i3 with a range extender is an EV. But a Volt is a hybrid.

 

[bl00tdi]

The myth of the Volt has been debunked. They have a direct mechanical linkage to the wheels when the engine is running and you are driving down the highway. It is NOT like a diesel-electric locomotive, which do not have any direct mechanical linkage (because there simply isn't a feasible way to make a transmission work for that sort of thing).

There is a youtube video about it somewhere, as well as several automotive magazine articles. Not sure where the misinformation started, though, but it was pretty common early on until finally someone actually took one apart. Not sure if GM leaked the wrong information accidentally or what.

Which myth is that precisely? There are three clutches along with a planetary gearset that allow for 4 primary modes of propulsion:


1. Single motor EV mode (primary traction motor MGB splined into sun gear, which turns planetary carrier - - > output to diff, clutch C1 locks ring gear in place)

2. Dual motor EV mode (same as before, except clutch C1 is released allowing the ring gear to rotate. Clutch C2 is applied connecting the secondary motor/generator MGA to the ring gear, which spins up allowing the sun/primary motor to spin slower, increasing overall efficiency.

3. Series hybrid mode (clutch C3 is applied to allow MGA to start ICE, which then turns MGA to generate electricity to replenish battery charge as MGB draws from the battery for propulsion with ring gear locked by C1. Clutch C2 is open so no torque from either ICE or MGA is driving the ring gear.)

4. Power split mode (clutches C3 and C2 are applied so that the ICE can turn the ring gear exclusively while MGA charges the battery, or both the ICE and MGA can do so in parallel. MGB exists here primarily in this mode to adjust the ring gear output ratio by varying sun gear RPM.


All of this I've confirmed myself using MDI/GD2 GM software to monitor transmission operations. I've seen the YouTube videos, and even Weber Auto was somewhat confused as to how it worked certain modes, which he admitted in the comment sections. The other animation videos and most articles are kind of a mess as well, as they lean on GM's poorly-worded descriptions. What makes it a range-extended EV is that it has a pure EV mode, unlike its competitors. Plug in hybrid connotes EV-only operation across all loads and speeds is not possible. In the end, is it a matter of semantics? Probably. Just wanted to clear some things up though.


Edit: Now I see which "myth" you were referring to. Didn't take the proper time to read through the string of posts you were replying to. My apologies.

 

[bl00tdi]

Based on these definitions the BMW i3 with a range extender is an EV. But a Volt is a hybrid.

Forgive me, I'm honestly not really familiar with how the i3 works. Marketing lingo aside, how are they different?

 

[IndigoBlueWagon]

The i3 with a range extender has a small engine in the back that charges the batteries. The engine cannot propel the vehicle directly.

 

[turbobrick240]

Which myth is that precisely? There are three clutches along with a planetary gearset that allow for 4 primary modes of propulsion:


1. Single motor EV mode (primary traction motor MGB splined into sun gear, which turns planetary carrier - - > output to diff, clutch C1 locks ring gear in place)

2. Dual motor EV mode (same as before, except clutch C1 is released allowing the ring gear to rotate. Clutch C2 is applied connecting the secondary motor/generator MGA to the ring gear, which spins up allowing the sun/primary motor to spin slower, increasing overall efficiency.

3. Series hybrid mode (clutch C3 is applied to allow MGA to start ICE, which then turns MGA to generate electricity to replenish battery charge as MGB draws from the battery for propulsion with ring gear locked by C1. Clutch C2 is open so no torque from either ICE or MGA is driving to the ring gear.)

4. Output split mode (clutches C3 and C2 are applied so that the ICE can turn the ring gear exclusive while MGA charges the battery, or both the ICE and MGA can do so in parallel. MGB exists here primarily in this mode to adjust the ring gear output ratio by varying sun gear RPM.


All of this I've confirmed myself using MDI/GD2 GM software to monitor transmission operations. I've seen the YouTube videos, and even Weber Auto was somewhat confused as to how it worked certain modes, which he admitted in the comment sections. The other animation videos and most articles are kind of a mess as well, as they lean on GM's poorly-worded descriptions. What makes it a range-extended EV is that it has a pure EV mode, unlike its competitors. Plug in hybrid connotes EV-only operation across all loads and speeds is not possible. In the end, is it a matter of semantics? Probably. Just wanted to clear some things up though.

That sounds like a pretty good description. I would argue that the range extended EV title is just GM marketing garbage. The Volt is a PHEV.

 

[bl00tdi]

That sounds like a pretty good description. I would argue that the range extended EV title is just GM marketing garbage. The Volt is a PHEV.

Fair enough. The distinction I made may be important if you're cross-shopping, though. Many people love the Volt because they are in much greater control over when the ICE runs versus the competition.

 

[El Dobro]

In the Gen 1 GM animation, the part where the ICE is linked in to the rest of the drivetrain is called 70 MPH Grade Driving. That's the only condition where the ICE is tied in.

 

[bl00tdi]

In the Gen 1 GM animation, the part where the ICE is linked in to the rest of the drivetrain is called 70 MPH Grade Driving. That's the only condition where the ICE is tied in.

The ICE can be tied in at much lower speeds than that. This entire discussion is proof positive of how poorly GM initially described the 4ET50's operation, and then spent years revising its message. The gouge on that is the misdirection was on purpose for competitive advantage.

 

[bl00tdi]

The i3 with a range extender has a small engine in the back that charges the batteries. The engine cannot propel the vehicle directly.

Sounds like series hybrid operation to me, just like mode #3 that I posted earlier. The real question is, can the driver demand maximum acceleration up to top speed in pure EV mode, or does it need the boost from the "range extender" to do so?

 

[IndigoBlueWagon]

Don't think it is. Here's a description:

The small and quiet two-cylinder petrol engine powers a generator that maintains the charge level of the high-voltage battery at a constant level so that the BMW i3 can continue to drive purely electrically. The Range Extender switches on automatically when the battery level is low.

 

[AntonLargiader]

As far as I know, both the i3 Rex and the Volt behave the same as far as the ICE goes; it only kicks in when the battery is dead and not for added power during operation. I've driven a fair number of miles in each. The operation of the i3 Rex was adapted a bit to the US market for regulatory reasons so it has either no HSOC or a very limited one. Many owners reflash the ECU for a deeper HSOC if they are heading toward the mountains.


To be classified in an advantageous way (I forget the exact term) the gas range had to be less than the battery range, and you had to deplete the battery first. Roughly speaking.

 

[bl00tdi]

Don't think it is. Here's a description:
The small and quiet two-cylinder petrol engine powers a generator that maintains the charge level of the high-voltage battery at a constant level so that the BMW i3 can continue to drive purely electrically.

The Range Extender switches on automatically when the battery level is low.

That's actually no different from the Volt when the battery is low (see mode #3 of my previous post). That production/conversion/consumption of energy in a serial setup is by definition serial hybrid operation. It's actually more efficient to tie the ICE in at some point due to the losses involved though, which is why mode #4 exists. The i3 presumably can't do it due to packaging limitations and there's actually a class-action lawsuit due to the "range-extender" not being able to keep up in a high load demand/low battery scenarios, with a dangerous and sudden loss of propulsion ensuing. Imagine chugging up a mountain pass or accelerating hard in a merge lane and suddenly losing half of your output....yea.....


P.S. "Purely electrically" is marketing drivel since the electrons are sourced from petrol.

 

[bl00tdi]

As far as I know, both the i3 Rex and the Volt behave the same as far as the ICE goes; it only kicks in when the battery is dead and not for added power during operation.

This is correct. However, with the Volt you can force the ICE on to maintain electric range for later, or use mountain mode to actually charge the battery up to make parallel output possible up steep grades. Very versatile.

And I see your bigger point too. Cars like the Clarity turn the ICE on for torque fill at higher loads, even if battery is full. Cars like the Prii plugins must turn the ICE on at high road speeds due to transaxle design limitations (max EV speed is admittedly higher than before, but still shy of top speed), again even with full batteries.

 

[oilhammer]

The i3 is not like a Volt. The i3-Rex is more like a Bolt with a little genset in the trunk.

 

[bl00tdi]

The i3 is not like a Volt. The i3-Rex is more like a Bolt with a little genset in the trunk.

Now we're talking about form-factor and packaging versus actual operation. Serial and parallel hybrid modes are what they are regardless of how big the ICE is or where its placed. The fact is that the Volt ICE can maintain battery charge without directly propelling the vehicle, just like the i3. It isn't limited to just that, however. It's a more complete and versatile solution to overall efficiency.

 

[oilhammer]

We're talking semantics, and definition. The Volt is, was, and always has been, a plug in hybrid. A pretty decent one, once you get past the GM rental car interior bits. The i3 is not. Not in anyone's "normal" definition of a "hybrid", which is the ability to operate the vehicle by electric or fuel directly, be it in series or parallel. The i3 is unique in that it is, to my knowledge, the only EV with [the option of] a standalone generator carried onboard. And they (BMW) purposely nerfed the size of the fuel tank specifically to discourage people from just driving it around with the generator running flat out to keep the batteries topped up enough to operate the car. In Europe, you can get a larger fuel tank for them supposedly. 3.5 gal instead of 2.1 or something like that.

 

[bl00tdi]

We're talking semantics, and definition. The Volt is, was, and always has been, a plug in hybrid. A pretty decent one, once you get past the GM rental car interior bits. The i3 is not. Not in anyone's "normal" definition of a "hybrid", which is the ability to operate the vehicle by electric or fuel directly, be it in series or parallel. The i3 is unique in that it is, to my knowledge, the only EV with [the option of] a standalone generator carried onboard. And they (BMW) purposely nerfed the size of the fuel tank specifically to discourage people from just driving it around with the generator running flat out to keep the batteries topped up enough to operate the car. In Europe, you can get a larger fuel tank for them supposedly. 3.5 gal instead of 2.1 or something like that.

A diesel-electric locomotive is technically a series hybrid vehicle because it generates torque (from an ICE) which is converted to electricity to turn traction motors without being directly coupled. This is a universally accepted definition (at least in automotive terms) and no different from the i3. Size, form-factor, and range don't really change anything. An EV is an EV whether the range is 40 miles or 400 miles, and a range extender (which is hybrid operation) is a range extender, whether the fuel tank holds 2 gallons or 20 gallons. We have to stick to actual operating principles or else the goalposts will keep moving, and arbitrary terms and definition will be used like, "It's not a real EV because it can only go 40-60 miles" "or this IS an EV because the wheels are never powered by the ICE". That's marketing talk, not actual nuts and bolts.

 

[IndigoBlueWagon]

So by your definition both the Volt and i3 with range extender are series hybrids, not EVs. Right?

 

[bl00tdi]

So by your definition both the Volt and i3 with range extender are series hybrids, not EVs. Right?

So first off, I didn't realize that there was a pure EV version of the i3 without the range extender. Like I said, I wasn't well-versed. With that said, let me take a step back and share what I would consider to be a basic definition of an EV, which is:


Can it achieve maximum acceleration and top vehicle speed using stored electricity alone, long enough to be useful (we're obviously not talking 800 feet of range here).


Teslas, Taycan, Leaf, i3 (both EV and rex version), Volt, Bolt etc can all do this. I would consider these all EV's. If my Volt's ICE had spun bearings, a seized water pump, and zero fuel in the tank, it would still be able to accomplish that. The fact that there's range-extending equipment on board is irrelevant to this.


The Prii, Pacifica, Cayenne hybrid, and Clarity, to name a few, can't. At some point the ICE must come on by design, even if the battery has charge remaining. So to answer your question, I would consider them both EV's until the battery is depleted, at which point range-extending equipment operates in hybrid mode (i3 in series, Volt in series/parallel). No mental gymnastics or arbitrary lines of delineation required.

 

[IndigoBlueWagon]

You're parsing this too much to be useful as a definition. I was looking for a clear industry definition. And based on what you've offered any vehicle with an iCE, whether connected to the drive wheels or not, is a hybrid. Which is where I started.

 

[oilhammer]

Yeah I'm with IBW on this one. An EV is all electric all the time. But whatever. I'll still be driving my diesels.

 

[bl00tdi]

You're parsing this too much to be useful as a definition. I was looking for a clear industry definition. And based on what you've offered any vehicle with an iCE, whether connected to the drive wheels or not, is a hybrid. Which is where I started.

I wanted to make a distinction between equipage and operation. But let me circle back to one of your original points which was that a i3 rex was an EV but a Volt was not. My contention was that they're both EREV's (extended range EV's) because they don't rely on the ICE at all so long as there's sufficient charge remaining and they both have range-extending mechanisms. And I'm not parsing, I'm trying to focus the discussion and highlight some common elements between these cars which can help with some understanding the differences between marketing speak and getting down to brass tacks. As I already stated, my Volt's ICE could blow tomorrow and I'd still be able to use the EV side of things in all conditions, all loads, at all speeds. What do you call that? I feel like I'm repeating myself though, so we'll just have to agree to disagree.


In this electrified space the Volt is a bit of an oddball because it's obviously not a pure EV, nor is it solely a PHEV (because it does have a pure EV mode unlike others), but it's not 100% an EREV either because the ICE can drive the wheels. It can utilize all of the above to maximize efficiency and flexibility. This is also part of the reason that it never really took off in sales; too complex to explain in a TV commercial or magazine ad and eventually was just lumped in with the other hybrids of the day (at a much higher cost, to boot). So I can understand why someone might be dismissive and just say that "all these plugins are the same" but it's is misguided at best and ignorant at worst, all due respect. There are enough subtle differences between all these vehicles for prospective owners to really appreciate if they do some digging while cross-shopping.