Charging an Electric Battery with Gas (a car does this)

austin2359

10 mW
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I was googling around and found this : https://www.cnet.com/roadshow/news/nissan-e-power-combines-gas-and-electric-but-not-like-a-typical-hybrid/

the new Nissan system, called e-Power, only uses the gasoline engine to charge the battery pack, not to drive the wheels.

I wonder if I could find a 52v configuration like this, that would allow me to essentially not have to worry about range but not have a gas motor just a gas generator.
 
I dont follow the EV stuff much but I thought there are hybrid cars out there that power the vehicle on gas, and electric as well as use the gas engine to power a generator to charge the battery while in motion not just regen braking.
While other EV's are purely electric, needing a charging station and running out of juice when driving your s.o.l.

Your talking about 52V so what is your vehicle? an ebike, an emotorcycle?

A quick google search
https://x-engineer.org/automotive-engineering/vehicle/hybrid/types-hybrid-electric-vehicles-hev/
 
This is different. the e-power system just charges the battery. it's not a normal hybrid. i have an ebike.
 
austin2359 said:
I wonder if I could find a 52v configuration like this, that would allow me to essentially not have to worry about range but not have a gas motor just a gas generator.
Gas motor on a trailer is a lot easier. Trailer pushes you, and you don't need any extra connection to the battery. Regen charges the battery.
 
JackFlorey said:
Gas motor on a trailer is a lot easier. Trailer pushes you, and you don't need any extra connection to the battery. Regen charges the battery.
This would be terribly inefficient and subject to failure.
 
fatty said:
This would be terribly inefficient and subject to failure.
?? Would be way simpler than adding a generator and charge controller to the mix. Gas engine driving a wheel is something that go-karts, mopeds and motorcycles do every day, and they are pretty robust. The design is, as they say, mature.

And it's MORE efficient. Gas engine -> wheel is way more efficient than gas engine -> generator -> charge controller -> battery -> motor controller -> motor -> wheel. The only time you will use the ebike system is when you want to go faster or climb a hill (then you will add more power) or when you want to charge your battery (via regen.) Other than that, you use the power as-is.
 
austin2359 said:
I wonder if I could find a 52v configuration like this, that would allow me to essentially not have to worry about range but not have a gas motor just a gas generator.
Probably not 52V, but plenty of 48V gas generators for charging
 
JackFlorey said:
?? Would be way simpler than adding a generator and charge controller to the mix.
Generator = motor, so this is added either way
Direct DC generators are available with integrated chargers

JackFlorey said:
And it's MORE efficient. Gas engine -> wheel is way more efficient than gas engine -> generator -> charge controller -> battery -> motor controller -> motor -> wheel. The only time you will use the ebike system is when you want to go faster or climb a hill (then you will add more power) or when you want to charge your battery (via regen.) Other than that, you use the power as-is.
It's not more efficient, hence the adoption of series hybrids. Running the ICE at peak efficiency as a generator more than offsets the conversion losses if you're already carrying an EV powertrain. This is readily apparent when comparing a DC generator against a kit bike motor.
Keep in mind, your regen charging requires a highly-lossy conversion to mechanical energy as well.
 
fatty said:
Generator = motor, so this is added either way
Nope. With direct drive, you only have one generator/motor - the bike's hub motor.
It's not more efficient, hence the adoption of series hybrids.
There are very few pure series hybrids. The Prius line are all parallel. The Volt claimed to be a series hybrid for years, then finally admitted they were series-parallel. This is due to efficiency considerations. From Green Car Reports:

"Today, the thing that has driven most automakers to series-parallel hybrids rather than pure series hybrids is a common scenario in U.S. driving: high-speed freeway driving. In such environments, multiple engineering teams over multiple decades have concluded that a mechanical connection to the engine offers better efficiency."

The only pure serial hybrid I know of in regular production is the BMW i3 series, which actually has a completely separate motor/generator. (They call it a 'range extender'.)
Keep in mind, your regen charging requires a highly-lossy conversion to mechanical energy as well.
Nope. Regen charging converts to electrical energy, not mechanical energy.

Again, it's all in the number of conversion steps, because each step costs you energy. Hence the parallel hybrid approach for efficiency.
 
JackFlorey said:
Nope. With direct drive, you only have one generator/motor - the bike's hub motor.
No, I mean ICE generator / ICE traction motor
Either design requires both a electric motor and ICE, so that point was a wash

JackFlorey said:
There are very few pure series hybrids. The Prius line are all parallel. The Volt claimed to be a series hybrid for years, then finally admitted they were series-parallel. This is due to efficiency considerations. From Green Car Reports:

"Today, the thing that has driven most automakers to series-parallel hybrids rather than pure series hybrids is a common scenario in U.S. driving: high-speed freeway driving. In such environments, multiple engineering teams over multiple decades have concluded that a mechanical connection to the engine offers better efficiency."
Only with inefficient traction ICEs coupled with early (underpowered) EV powertrains at the high power (density) required for freeway driving.

JackFlorey said:
The only pure serial hybrid I know of in regular production is the BMW i3 series, which actually has a completely separate motor/generator. (They call it a 'range extender'.)
Also the Nissan e-POWER platform as subject of this thread, Mazda rotary RE, etc.

JackFlorey said:
Nope. Regen charging converts to electrical energy, not mechanical energy.
No, I mean regen converts mechanical energy to electrical energy, same as an ICE generator, so this point would likewise be a wash, except that a generator is far more efficient than traction ICE > regen.

JackFlorey said:
Again, it's all in the number of conversion steps, because each step costs you energy. Hence the parallel hybrid approach for efficiency.
Conversion steps are certainly important, but again, it's not all in the number of conversion steps. A modern small gas generator is easily twice as efficient (g/kWh) as a bike kit motor, and the ICE itself is the overwhelming determinant of overall efficiency.

JackFlorey said:
Gas engine -> wheel is way more efficient than gas engine -> generator -> charge controller -> battery -> motor controller -> motor -> wheel. The only time you will use the ebike system is when you want to go faster or climb a hill (then you will add more power) or when you want to charge your battery (via regen.) Other than that, you use the power as-is.
This isn't accurate, as you're missing all the intermediate mechanical conversion steps between gas engine > wheel. As above, you're also missing that all those same generator steps apply for regen -- except again, charging via traction ICE > regen is a fraction of the efficiency of a gas generator. I get why you're not including it though, as below..

But I don't fundamentally disagree with you, because we're assuming different use cases. If you're using a traction ICE with mechanical linkage, it's a motorized bicycle (restricted) and it doesn't make sense to bring an EV powertrain at all -- just size the traction ICE appropriately. Which is the same argument against non-plug-in parallel hybrids -- they're not attractive on their merits in any way, and only become competitive with external incentives (tax breaks, HO vehicle lane access, wokeness, etc).

But this thread stipulates an EV powertrain. If you're already paying that penalty, you might as well make the most of it with a gas generator.

The future is series-hybrid with Atkinson cycle generators and then FPLGs.
 
I hate one liners, but an important thing to consider is legally this is still an ebike, not a gas bike. If the gas only regenerates the battery it's not a gas bike and you won't have the police contact that you might get from a gas bike.
 
austin2359 said:
I hate one liners, but an important thing to consider is legally this is still an ebike, not a gas bike. If the gas only regenerates the battery it's not a gas bike and you won't have the police contact that you might get from a gas bike.

You hope! It's really not up to you to decide. I think any local judge would be very likely to decide you're riding an unsafe, unregistered, uninsured motorcycle, and dispose of your case accordingly.

Pusher trailers are inherently hokey-- I did build one for myself-- but I would not tease the dragon to ride something as goofy as a stinking noisy gasoline generator trailer rig, when I could simply ride a legit motorcycle or tuk tuk instead. What's your motivation here?
 
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