Will EV's get even more efficient?
Discussion
Yes increased battery density reduces weight which will improve efficiency.
Small gains might still be possible in terms of the motors but they're already highly efficient, seriously limited returns left for the investment to further improve any of the powertrain really.
Improvement of aero modelling, wind tunnel and CFD use will continue to improve higher speed efficiency, but again, only so much is possible.
Cars are also getting simpler to assemble which starts to reduce manufacturing efficiency.
Lots of little improvements here and there then. But the next big leap is definitely higher density batteries!
Small gains might still be possible in terms of the motors but they're already highly efficient, seriously limited returns left for the investment to further improve any of the powertrain really.
Improvement of aero modelling, wind tunnel and CFD use will continue to improve higher speed efficiency, but again, only so much is possible.
Cars are also getting simpler to assemble which starts to reduce manufacturing efficiency.
Lots of little improvements here and there then. But the next big leap is definitely higher density batteries!
Self driving tech should increase efficiency on long journeys by allowing cars to directly communicate with each other and allow very close following or drafting. Of course this is theoretically possible with ICE too, but it seems to be more welcome in more computerised EVs. It will need manufacturers to agree on several standards, for networking etc. I think if you could draft behind a large lorry for a long section of motorway there would be huge efficiency savings to be made.
J4CKO said:
As designs and batteries improve, or are we pretty much at the peak of efficiency ?
If, for example battery tech halves the weight, would that make a huge difference ?
Suppose then the whole car can be lighter if its maybe 150/200 kilos less batteries.
They make what will sell. If, for example battery tech halves the weight, would that make a huge difference ?
Suppose then the whole car can be lighter if its maybe 150/200 kilos less batteries.
Imagine an EV mk1 Honda Insight. I'd imagine with a small battery and motor 10 miles per Kwh would be entirely possible.
People want conventional looking crossovers or retro superminis with atleast 200hp and 500 litres of boot space.
ChocolateFrog said:
J4CKO said:
As designs and batteries improve, or are we pretty much at the peak of efficiency ?
If, for example battery tech halves the weight, would that make a huge difference ?
Suppose then the whole car can be lighter if its maybe 150/200 kilos less batteries.
They make what will sell. If, for example battery tech halves the weight, would that make a huge difference ?
Suppose then the whole car can be lighter if its maybe 150/200 kilos less batteries.
Imagine an EV mk1 Honda Insight. I'd imagine with a small battery and motor 10 miles per Kwh would be entirely possible.
People want conventional looking crossovers or retro superminis with atleast 200hp and 500 litres of boot space.
I think we could be in the market for a small hatchback EV at some point, they are getting there but in no rush and can wait until the offerings are so compelling we cant ignore them any longer.
No, not to any great degree.
Regarding weight, EVs have bidirectional motors so the majority of energy consumed through acceleration of a large mass is returned to the system through regeneration braking.
Regarding component efficiency, they're already very efficient across the power train. There are also losses in the charging interface to be considered and other effects like battery heating and cooling in winter/summer and when rapid charging. So you're more likely to see efficiency improvements at the wall meter than on the dashboard.
There are fleet-wide savings to be made as compromised designs sharing platforms with ICE are phased out. But even that isn't clean cut, with cars like Niro/Kona performing well on efficiency despite being shared with Hybrid models. Tesla obviously don't suffer this issue and have some of the most efficient models.
The biggest impact to efficiency is seen on both ICE and EV. Large SUV-esque vehicles are not aerodynamically efficient. So especially at motorway speeds you will see poor performance across all cars. Kia have even put in the 'blade' feature on the new Niro.
Regarding weight, EVs have bidirectional motors so the majority of energy consumed through acceleration of a large mass is returned to the system through regeneration braking.
Regarding component efficiency, they're already very efficient across the power train. There are also losses in the charging interface to be considered and other effects like battery heating and cooling in winter/summer and when rapid charging. So you're more likely to see efficiency improvements at the wall meter than on the dashboard.
There are fleet-wide savings to be made as compromised designs sharing platforms with ICE are phased out. But even that isn't clean cut, with cars like Niro/Kona performing well on efficiency despite being shared with Hybrid models. Tesla obviously don't suffer this issue and have some of the most efficient models.
The biggest impact to efficiency is seen on both ICE and EV. Large SUV-esque vehicles are not aerodynamically efficient. So especially at motorway speeds you will see poor performance across all cars. Kia have even put in the 'blade' feature on the new Niro.
ChocolateFrog said:
They make what will sell.
Imagine an EV mk1 Honda Insight. I'd imagine with a small battery and motor 10 miles per Kwh would be entirely possible.
People want conventional looking crossovers or retro superminis with atleast 200hp and 500 litres of boot space.
No, the Aptera was making claims of 10miles/kWh and that's a full year drop pod. The Insight mk1 is timid in comparison.Imagine an EV mk1 Honda Insight. I'd imagine with a small battery and motor 10 miles per Kwh would be entirely possible.
People want conventional looking crossovers or retro superminis with atleast 200hp and 500 litres of boot space.
J4CKO said:
As designs and batteries improve, or are we pretty much at the peak of efficiency ?
If, for example battery tech halves the weight, would that make a huge difference ?
Suppose then the whole car can be lighter if its maybe 150/200 kilos less batteries.
The most obvious example to draw conclusions from is the Merc EQXX concept car. If, for example battery tech halves the weight, would that make a huge difference ?
Suppose then the whole car can be lighter if its maybe 150/200 kilos less batteries.
That is a 4-seater (only just) car that achieves better than 620 miles or 1000 km real-world range from its 100 kWh battery.
Which is pretty astounding if you ask me.
OK, it probably cost 100 million something or others to design and build it, but it exists as a road legal 4-seater luxury car, and showcases what can be achieved.
First and foremost on the list of things that they improved is the aero.
Combining active aero, a 0.17 drag coefficient and a relatively low frontal area is probably not yet feasible for a production car, but it does show the direction manufacturers should be heading in, and if Hyundai's recent effort is anything to go by, it looks like they are listening.
The teardrop shape, narrower rear track, skinny, ultra low resistance tyres and flat, enclosed faced wheels, whilst not to everyone's taste looks-wise, are a result of the function over form design approach. In the knowledge that the car looks the way it does because that's what nature requires it to look like makes it all the more attractive to my eyes.
Second on the list was to eliminate as many different parasitic losses in the car's electrical system as possible.
Starting with the battery, they adopted a novel arrangement by using controllable airflow under/through the car to cool the battery, thus eliminating liquid-cooling which in turn decreased energy lost to cooling, as well as significantly reducing both the volume and weight of the battery, which then has a knock-on effect to the rest of the car.
Efficiency of the motor and its controller was also pushed as high as possible with motorsport grade materials and pushing battery voltage up to 900V. Solar panels on the roof were used for an additional 25 km of range.
Thirdly, they stripped weight form everything else they possibly could, particular the metallic materials all over the car. Things like aluminium brake discs, composite suspension springs, organic aluminium castings, composite doors, etc, were used. Kerb weight was reduced to around 1750 kg, still not a lightweight car by any stretch, put pretty impressive for a 100 kWh 4-seater EV, although it's fair to say that durability of some of these weight reduction measures may not make them applicable to a production car.
To answer your question then, there is seemingly plenty more to come in incremental improvements towards reducing energy consumption.
It's interesting to consider how little there is left to do to increase EV efficiency, even after just a decade of having EV's. I suppose it's because they were born out a need to be more efficient, and had to hit that target on day one to justify the politicians and auto makers to head down the EV route.
Compared to the ICE car, that was born from a fairly carefree desire for mass personal transport, with no initial thought about efficiency.
EV efficiency will improve, pretty much all things improve over time. But I really don't think there is headroom for any major (or interesting..) leap forward other than battery density. My car has a 600kg battery, if battery density were doubled as it will be with solid state cells (might be a long wait) then it could maintain it's current more than adequate range and be 300kg lighter. That's the same weight difference as four adults! - or an adult, if you're reading this in America. Anyone that has driven a family car with four additional adults on board will know that the weight is easy to feel and has a tangible performance hit. I can't imagine anything else in EV world that could have as greater effect on efficiency.
Compared to the ICE car, that was born from a fairly carefree desire for mass personal transport, with no initial thought about efficiency.
EV efficiency will improve, pretty much all things improve over time. But I really don't think there is headroom for any major (or interesting..) leap forward other than battery density. My car has a 600kg battery, if battery density were doubled as it will be with solid state cells (might be a long wait) then it could maintain it's current more than adequate range and be 300kg lighter. That's the same weight difference as four adults! - or an adult, if you're reading this in America. Anyone that has driven a family car with four additional adults on board will know that the weight is easy to feel and has a tangible performance hit. I can't imagine anything else in EV world that could have as greater effect on efficiency.
EV will diverge from cars as we know it... the structure and layout can be altered as no engine to take care of, better space utilisation,
as auto driving comes in and gets better there may be no need to actually drive, that function taken over by the car. so that lets the interior be redesigned and better utilised.
Functionality of the motor drive and battery efficiency - range and charge times improve - battery being able to absorb huge charge rates quickly and with no issue. range up into 500 miles or more...
internal combustion was at its peak, now we have to develop electric drive trains.
20 or 30 years from now the car scene will be completely different. thats for sure
as auto driving comes in and gets better there may be no need to actually drive, that function taken over by the car. so that lets the interior be redesigned and better utilised.
Functionality of the motor drive and battery efficiency - range and charge times improve - battery being able to absorb huge charge rates quickly and with no issue. range up into 500 miles or more...
internal combustion was at its peak, now we have to develop electric drive trains.
20 or 30 years from now the car scene will be completely different. thats for sure
They will eventually become more and more expensive to run due to evener increasing electricity costs once fuel becomes less of a thing all that profit will be drawn away into home and work charging to recoup that revenue, so that there will be markets like there are now for very light, cheap economical vehicles with less frills, and good mileage and then the stuff most rich people will buy ike Tesals and family cars that will be very dear but not so good on mileage and range
J4CKO said:
As designs and batteries improve, or are we pretty much at the peak of efficiency ?
If, for example battery tech halves the weight, would that make a huge difference ?
Suppose then the whole car can be lighter if its maybe 150/200 kilos less batteries.
This is the start of the curve unlike ice which is towards its end. Things will only speed up development wise as the market for ice shrinks and bev take over. Once the big boys and everyone else are fully focused 100% on bev it’ll take off. If, for example battery tech halves the weight, would that make a huge difference ?
Suppose then the whole car can be lighter if its maybe 150/200 kilos less batteries.
bmwmike said:
Evanivitch said:
Regarding weight, EVs have bidirectional motors so the majority of energy consumed through acceleration of a large mass is returned to the system through regeneration braking.
My bold - majority? Are you sure about that? But you don't net more in real terms because the car is heavier. A lighter car will be more efficient in every regard.
Griff74 said:
Yes less weight, better efficiency from the motors (motors directly inside each driven wheel for less friction looses etc), better aerodynamics, better battery and power control systems etc etc.
Wouldn't motors in the wheels greatly increase the unsprung weight & have an impact on ride quality? How much does a (say) 120hp electric motor (for 2 wheel drive) weigh?Glosphil said:
Wouldn't motors in the wheels greatly increase the unsprung weight & have an impact on ride quality? How much does a (say) 120hp electric motor (for 2 wheel drive) weigh?
Not to mention it being an incredibly harsh environment for a high power precision electric motor to operate in. Extreme vibration, shock, heat, cold, water, salt, dust, dirt, the lot.bmwmike said:
Evanivitch said:
Regarding weight, EVs have bidirectional motors so the majority of energy consumed through acceleration of a large mass is returned to the system through regeneration braking.
My bold - majority? Are you sure about that? Don't confuse acceleration of mass with other losses.
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