One thing that always puzzled me was how the gas engines in hybrids were so efficient. Technology Connections has a great video explainer: https://www.youtube.com/watch?v=KnUFH5GX_fI
tl;dw: constant RPM and a weird stroke geometry where the power stroke is longer than the other strokes to extract more energy from the expanding gasses.
I'm surprised there isn't more effort to create hybrids in reverse--an electric car with optional gas generator. The gas generator could run at constant speed, never changing RMP, while the battery handles constant changes in acceleration. The idea is not mine. I've heard about it in China
That is exactly what ePOWER is, that configuration is called a series hybrid and is more commonly seen in heavy industry like diesel trains or trucks in the mines (for better or worse).
More recently effort is also going into series hybrids for public road haulers, which I personally think is a great application for it since you can potentially put a lot of the equipment into a hot-swappable dolly.
I drove a Nissan Note (Nismo esition) with ePower and it could happily spin the wheels when taking off, not something you normally get out of a tiny economy hatchback. I think it has 140kw electric drivetrain? 140kw is pretty sporty when delivered instantly.
Range extender EVs made a lot more sense a decade a go when batteries were much more expensive, and fast chargers were not yet ubiquitous. Then range extenders were more affordable than EVs and could go to places EVs couldn't.
Now these EREVs are mostly luxury niche of big cars (where extra space taken by two power trains doesn't matter) for people who don't want to spend 20 minutes at rapid chargers on that yearly long trip they do. Or for people who live in some global warming ignoring backwater[1] that hasn't built out rapid charger yet.
[1] even China has ubiquitous fast charging network now
The volt was never popular enough, unfortunately. Right around the time we were looking to buy a new car, and had the Volt high on our list, the retired the product line.
It seems to me you’re talking about a range extender, which lots of Chinese EV makers use. Many do buy them but sometimes you get the worst of both worlds: weighty like an EV and the heat, vibration, exhaust of a petro car. For most people the extended range is only needed very occasionally but you have to carry the ICE system the whole time.
Depending on the compromises you're willing to make, a small gas engine that doesn't run very often isn't a lot of excess weight, and it's not going to make heat, vibration, and exhaust except when it's running ... which could be 30 minutes a month (to keep it healthy) plus whenever you actually need the extended range.
Since it's just for range extension, you could maybe stuff the engine in the rear, so you don't have to pipe exhaust under the whole car. Although then you probably want to pipe coolant to a radiator in the front and have to protect that piping... but at least it's only coolant hot and not exhaust hot. The engine noise would be away from the driver at least.
You said you didn't want the heat of a gas car, but you might choose to run it a little bit more in the cold to help warm the interior on cold days (especially at startup).
Potentially, but not really likely, you could try to make it modular-ish... attach it when you need it, leave it in your garage otherwise. But I think it's going to be too heavy ... I have a 7200 W portable generator which is roughly half of what an EV uses at cruising speeds, and it takes two people to lift it. Automotive engineers do amazing things, but I don't think they're getting twice the power and less weight and easier to move...
I really love what Edison are doing, I have no skin in the game I just think it's a great business ethos.
Feom a fictional perspective I also dig the rugged blend of electric industrial equipment and utilitarian design. Like a mad-max solar punk, rather than a utopian one.
I picture them pulling up to a makeshift solar outpost en-route, in the middle of the wasteland desert, covered in red dust, the thick sheet metal scarred from raiders...
You may be interested to read / watch videos of Audi's RS Q e-tron they raced in the Dakar Rally and even won with this type of powertrain - https://en.wikipedia.org/wiki/Audi_RS_Q_e-tron
Yup, my friends had one and loved it despite the... unique styling.
They live in the Puget Sound area, and both work at the same place. It worked out to where they could do their commute, and ordinary errands entirely on battery, and only needed the range extender if they were going into downtown Seattle or on a road trip or such.
There were several of them: the first and second generations of Chevy Volt, Fisker Karma, BMW i3, and a couple of Chinese brands.
They're less efficient than parallel hybrids at high speeds (on a freeway). And you also need a fairly sizeable engine to keep up with the consumption at freeway speed, so at this point you might as well just throw in a planetary gearbox.
The Chevy Volt (and it's predecessor the GM 2-mode hybrid, and the Allison power-split hybrid) was a work of art. It is fundamentally a planetary gearbox, with 2 motor-generators.
In ICE mode, under 35 MPH, it worked as a series hybrid. Above 35, the engine mechanically connected to the wheels. One motor-gen extracted power and fed it to the other, acting as a CVT in parallel. This provided the ratio changes needed for the small engine.
It was way too complicated and expensive the two times they tried it (2008, then the Volt). It was successful and lives on to this day in its original application: city buses.
Planetary gear plus 2 motor-generators is 'Toyota Synergy Drive' and also used by Ford and Stellantis in some hybrid models. At least the Ford C-Max and Chrysler Pacifica hybrids use this style drive train. I'm not on top of all the hybrids, but I'd guess if 4 car makers do it, there's others to be found.
It makes a lot of sense, works well, and is very durable... as long as Ford didn't forget to heat treat a bearing or whatever they messed up in early C-Maxes.
Nice to see the packaging improvements, but the modularity of the original leaf motor enabled them to be come a budget staple motor choice for ev conversion
Hopefully it’s better than the second gen. Gas engine front only puts power to one wheel and electric rear only puts power to one wheel while the other two sit idle.
Bad state for a mild 4x4 unless you keep it on pavement.
Exactly, as owner of one of the latest versions of Nissan cars with e-Power, I just can say that it is extremely inefficient, especially during winter, plus it isn't recognised at all as hybrid vehicle in Germany (it misses the "E" at the end of the car plate).
For comparison, the full classic gasoline engine with manual gearbox consumes less gasoline than the e-Power one. This is just some pure greenwashing, that isn't even explained at car dealerships and people can't say anything about it, when you ask for information.
tl;dw: constant RPM and a weird stroke geometry where the power stroke is longer than the other strokes to extract more energy from the expanding gasses.
A.k.a. Atkinson-cycle (1882): https://en.wikipedia.org/wiki/Atkinson_cycle
And yes the Atkinson cycle helps
More recently effort is also going into series hybrids for public road haulers, which I personally think is a great application for it since you can potentially put a lot of the equipment into a hot-swappable dolly.
I drove a Nissan Note (Nismo esition) with ePower and it could happily spin the wheels when taking off, not something you normally get out of a tiny economy hatchback. I think it has 140kw electric drivetrain? 140kw is pretty sporty when delivered instantly.
Now these EREVs are mostly luxury niche of big cars (where extra space taken by two power trains doesn't matter) for people who don't want to spend 20 minutes at rapid chargers on that yearly long trip they do. Or for people who live in some global warming ignoring backwater[1] that hasn't built out rapid charger yet.
[1] even China has ubiquitous fast charging network now
Since it's just for range extension, you could maybe stuff the engine in the rear, so you don't have to pipe exhaust under the whole car. Although then you probably want to pipe coolant to a radiator in the front and have to protect that piping... but at least it's only coolant hot and not exhaust hot. The engine noise would be away from the driver at least.
You said you didn't want the heat of a gas car, but you might choose to run it a little bit more in the cold to help warm the interior on cold days (especially at startup).
Potentially, but not really likely, you could try to make it modular-ish... attach it when you need it, leave it in your garage otherwise. But I think it's going to be too heavy ... I have a 7200 W portable generator which is roughly half of what an EV uses at cruising speeds, and it takes two people to lift it. Automotive engineers do amazing things, but I don't think they're getting twice the power and less weight and easier to move...
Disclosure: I have a small investment in them.
Feom a fictional perspective I also dig the rugged blend of electric industrial equipment and utilitarian design. Like a mad-max solar punk, rather than a utopian one.
I picture them pulling up to a makeshift solar outpost en-route, in the middle of the wasteland desert, covered in red dust, the thick sheet metal scarred from raiders...
https://www.motortrend.com/features/what-is-an-erev-extended...
the ICE extender was an option.
They live in the Puget Sound area, and both work at the same place. It worked out to where they could do their commute, and ordinary errands entirely on battery, and only needed the range extender if they were going into downtown Seattle or on a road trip or such.
They're less efficient than parallel hybrids at high speeds (on a freeway). And you also need a fairly sizeable engine to keep up with the consumption at freeway speed, so at this point you might as well just throw in a planetary gearbox.
In ICE mode, under 35 MPH, it worked as a series hybrid. Above 35, the engine mechanically connected to the wheels. One motor-gen extracted power and fed it to the other, acting as a CVT in parallel. This provided the ratio changes needed for the small engine.
It was way too complicated and expensive the two times they tried it (2008, then the Volt). It was successful and lives on to this day in its original application: city buses.
It makes a lot of sense, works well, and is very durable... as long as Ford didn't forget to heat treat a bearing or whatever they messed up in early C-Maxes.
For comparison, the full classic gasoline engine with manual gearbox consumes less gasoline than the e-Power one. This is just some pure greenwashing, that isn't even explained at car dealerships and people can't say anything about it, when you ask for information.
Works like (?) an EV, it isn't an EV.