EV general discussion

chanjy said:
Note how the Taycan gets pretty good efficiency at higher speed while every other car is a 1 speed and it's not as efficient at higher speeds
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is there much data on how much it helps the taycan ? tesla does have different ratios on the front/rear motors so can do something taycan like.

whether electric car could ever benefit from a much more traditional gearbox, peak efficiency in below ev example 6K rpm .. so if the efficiency/weight penalty of a nice zf gearbox was 5% or less could be the future ; I guess you need gearboxes for evlorries anyway so the R&D will continue until cars want them again;
formula-e doesn't have them ?
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b0rn2sk8 said:
When you say higher speed, isn’t that well above licence losing speeds?

I can’t say I’ve looked at ‘autobahn’ efficiency, I’d have thought a Tesla is still better, they start from a much higher base at lower speeds?
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Just 70mph compared to 30 for ice comparison.


If you mean higher speed in reference to BEV then Taycan the gear allows a higher top speed for paper spec without trading it against 0-60 but yes also helps autobahn efficiency with the motor running at a sweeter speed which is good for sustained high speed running by avoiding derating the power electronics through heat build up etc. 800V of course starts that off properly with the lower currents.

EDIT. Good graph shows it well. Multi speed gearbox gives you better efficient and better access to torque if the driver demands.

Formula E will be rules anyway and weight simplicity, first season has 5 gears.... I think now they can chose anywhere between. I’m sure more multi speed gearboxes will come but it’s the space constraints that make high power and multi speed gearbox fit in a car difficult.
 
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Bosch EV+CVT transmission prototype - insightful comment. ( https://www.greencarcongress.com/2021/07/20210710-bosch.html )

The most vulnerable part of an EV is the battery. Its total life is always too short and any means to prolong its life is always welcome.
High surge currents resulting from high torque demand (e. g. accelerating whilst towing) certainly make no contribution to enhance life expectancy. A transmission achieves exactly that. It is absolutely necessary to convert a small torque to high one without excessive harmful drain on the battery. I'm convinced that the best way to cope with such problems is by means of a tranny and what could be better suited for that purpose then a E-CVT with a metal band? Anyone?
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Jonnycoupe said:
I don’t think “exact same physics” is fair.

ICE tends to get more efficient with higher road load to meet that power demand. Unlike EV where the relationship is far more linear.
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Wait, are you claiming that the physics of fluid dynamics differ for an EV vs an ICE? What you are describing about gearing is not physics but engineering.

So if you take diesel VW Golf and a BEV Golf, both will lose a significant amount of efficiency when going from 55 to 75mph. While you are correct an ICE will be marginally better at higher speeds due to the way they are "engineered", but the revers is true for EVs at slower speeds.
 
Not quite, just the physics of how tractive effort to overcome aero load is generated in a fairly different way to avoid using 'exact'. The road load increases to increase consumption, efficiency isn't really the word as an ICE might well be more efficient at 75mph in terms of its BSFC (Brake Specific Fuel Consumption). :)
 
I'm not going to argue semantics, suffice to say we agree that increasing speed significantly increases air pressure resistance regardless of what powers the car.
 
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ICDP said:
Just wanted to add that so many ICE drivers bring up the old "the grid wouldn't cope if we all drove electric cars", because they mistakingly believe everyone charges their EV every night at the same time. I ask them if everone turns up at the fuel pump the same time as you do they?

The truth is the grid could handle that scenario just fine with some basic planning and incentives.

https://www.nationalgrid.com/storie...ries/can-grid-cope-extra-demand-electric-cars
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Yeah I hear this one from my parents a lot. I've never known anyone to suddenly start worrying about national grid before :) but there could be something more sinister there, if you get to the news source of where that headline came from I bet its was an oil/ICE industry elec car smear campaign fund.

I've noticed a lot more electric cars on the road lately. Range be damned, elec cars are just better, I want one :)

Fully Charged news is that Tesla are opening up their charging network to all cars.. so thats nice.
 
keyser said:
I've noticed a lot more electric cars on the road lately. Range be damned, elec cars are just better, I want one :)

Fully Charged news is that Tesla are opening up their charging network to all cars.. so thats nice.
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A year ago I had serious range anxiety with my Audi E-Tron 50. But after a year of owning it and realising it is fine for the 99% trips and only takes a small bit of planning for longer ones. This thing is Zen on wheels and I feel more relaxed getting out of it than when I get in. :)

As for the Tesla thing it is a business decision because Norway (and I think Germany) basically told Tesla they would not get any government grant money to install their chargers until they were open to all makes of EV. So don't read this as Elon Musk being all generous and kind and doing it for the good of all human kind.

https://electrek.co/2021/06/24/tesl...ercharger-network-other-automakers-next-year/
 
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Be interesting how the Tesla opening up works, they've already talked about charging more for slow charging cars clogging up their stalls. Be interesting to see what their definition of slow charging will be, 75kw, 100kw, 125kw? And then what kind of prices they'll be charging to non Tesla people, their speeds will be comparable to Ionity all be it only 400v so i wouldn't be surprised if for a non Tesla slower <100kw car it could be like 70-80p+ a kwh

But even if it is like that it's still a massive win for EV drivers as most only need to rapid charge up very very infrequently so i'd be happy to pay the equivalent of petrol costs for the couple of times a year i actually needed it for the reliability and quantity of the Tesla chargers.
 
It’s an interesting one to watch . Other issue is first comments on it suggest Tesla want IP in exchange for access. Will need a dedicated app to Atleast handshake the VIN to the Tesla network to try repeating the plug and charge experience and then of course the charger will have to deal with the myriad CCS protocol executions to maintain that reliability.
 
I can’t imagine the other car makers will be happy with Tesla charging their customers 70-80p if they also need to hand over IP.

I also can’t imagine Tesla or Tesla owners being happy that a load of BMW i3s or Hyundai Ionics are hogging the super chargers, particularly at MSAs where there are few other CCS chargers but a load of Tesla chargers which are already busy like South Mimms (A1/M25).
 
Do i3s and Ioniqs even have CCS chargers that could use the Tesla supercharger?

I expect there will be some sensible limits to it (eg. additional cost per minute if charging below a certain speed)
 
chanjy said:
Do i3s and Ioniqs even have CCS chargers that could use the Tesla supercharger?

I expect there will be some sensible limits to it (eg. additional cost per minute if charging below a certain speed)
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They certainly do and most ‘gen 1’ EVs only pull 38-42kw from the plug and there are tens of thousands of them out there now.
 
chanjy said:
Do i3s and Ioniqs even have CCS chargers that could use the Tesla supercharger?

I expect there will be some sensible limits to it (eg. additional cost per minute if charging below a certain speed)
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Yes CCS, its only really the Zoe which is the odd ball with only Type2 AC for all its charging, don't forget the Model S uses the Type 2 plug but modified standard for both AC & DC rather than J1772. Which is why when i went to Rugby services in a Model S I clearly didn't realise all 12 chargers were only CCS so couldn't charge and had to use the big bulky CHadeMO adaptor :cry:
 
sovietspybob said:
Be interesting how the Tesla opening up works, they've already talked about charging more for slow charging cars clogging up their stalls.
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I thought tesla in the usa ca have penalties at peak/holiday times if you want to top off the tank.

ICDP said:
As for the Tesla thing it is a business decision because Norway (and I think Germany) basically told Tesla they would not get any government grant money to install their chargers until they were open to all makes of EV.
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if tesla have been getting uk grant money then the tax payer could, too, feel justifiably annoyed, I don't recall that recent motorway charger monopoly report discussing tesla,
otherwise that would have been in the news.
 
b0rn2sk8 said:
They certainly do and most ‘gen 1’ EVs only pull 38-42kw from the plug and there are tens of thousands of them out there now.
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Jonnycoupe said:
Yes CCS, its only really the Zoe which is the odd ball with only Type2 AC for all its charging, don't forget the Model S uses the Type 2 plug but modified standard for both AC & DC rather than J1772. Which is why when i went to Rugby services in a Model S I clearly didn't realise all 12 chargers were only CCS so couldn't charge and had to use the big bulky CHadeMO adaptor :cry:
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Poverty Zoe owner here without a CCS port lol

Although I think the newer ones do have it.

I'd still be shocked if Tesla allowed a free for all on the superchargers. I'm sure there would be limits or conditions around use to avoid ******* off all the Tesla fanboys :D
 
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