EV Discussion thread

thevilla

Do you think you could stall an EV with manual gears?  It's another Toyota tactic to delay delay delay...

JKenH

How far can you go in an electric car?

No spoilers, you have to decide if it’s worth reading with that title and me posting it.

https://www.autotrader.co.uk/content/news/how-far-can-you-go-in-an-electric-car

Martyn1981

Grumpy_chap said:

JKenH said:

Lexus in development of a manual transmission for electric cars

I'm not sure why Lexus would bother developing a manual transmission for an electric car given their (and Toyota's) abject reluctance to actually develop a proper fully-EV range of vehicles.  They'll have this manual transmission but no EV's to fit that into.  Also an odd thing for Lexus to say is an important criteria for a car given all their hybrids are not (so far as I am aware) available with manual gearbox.  In fact, do Lexus even offer any cars with a manual transmission at present?

I am also rather confused as to why a manual transmission would be desirable or even appropriate for an EV.  

A conventional ICE is fitted with a gear box between the drive unit (engine) and the wheels, so there is a need to change gears and that gear-changing process can be manual or automatic.  There are alternatives that use CVT automatic gear boxes, but these are not the majority of ICE cars (though a lot of Toyota's, even those that are not hybrid).

As I understand it (with simplifications), though, an EV does not have a gear box in the same way as the electric motor is an inverter-driven variable speed drive and just runs faster or slower depending on the required wheel speed.  That means the motor can be direct-coupled to the drive.  That means that an EV motor is always at the optimum speed for the conditions.  Then, a "manual" EV would still have the same inverter-driven variable speed drive but instead of allowing that motor speed to vary continuously, to achieve "manual" would need the motor to have a range of set speeds that the motor operates at and a switch to select a higher set speed or a lower set speed.  Which would be introducing an inefficiency to the system where none needs to exist.  The result would be higher energy use, lower range in the EV compared to an EV that is just allowed to operate and take advantage of the full inverter-range.

Maybe my understanding is entirely wrong and someone will correct me.

I think you are right. I won't pretend to understand the impact on electric motors, torque and efficiency, but I've read loads of comments, and 'detailed' arguments (that I couldn't really follow) where gearing is less important for a BEV since torque is ~100% and a flat curve, until high speeds are reached then it starts to decline.

So with an ICE you are using gears to raise the rpm up to the sweetspot for efficiency, but of course being a curve that's a very narrow window (I think 1,300-1,500rpm for a HGV, hence the high number of gears (upto 16) to achieve this).

It doesn't mean that gears can't be a benefit to an EV, and a few have gears, the Taycan is quite famous for having two. The original Tesla Roadster is infamous for the problems and delays they had before dropping the 2 speed gearbox (during development) and going for a single speed. The Tesla S & X Plaid models avoid it by running the motors to even faster speeds - they wrap the motors in a carbon sleeve due to the forces involved.

I recall during the original Tesla Semi launch event, one eagle eyed spectator, whilst crawling under the truck, noticed that the two gearboxes (one on each rear axle, with two motors to each) had different ratios. This would seem to be for added torque on pull off, and higher efficiency at speed. Not sure if this is still the case, as they've moved to 3 Plaid motors, one permanently attached, and the other two kick in when more power is needed.

So, it seems that 2 gears may be slightly more efficient, v's a single gear direct drive (with reduction gear as the motors spin so fast), but adds mechanical complication and losses which can negate the savings.

I may have this wrong, but I don't think BEV's even have a reverse gear. ICE's need it as the engine only spins in one direction, so to reverse the drive an extra cog has to be introduced, but a BEV can reverse the spin of the motor.

Just thought, you also have the differential whose gear ratio will reduce rpm's and increase torque (as per my post about the Trans-Am with a 'racing rear diff', lowering top speed, and adding way too much torque/acceleration for wet British roads). I think EV's have an electric diff that operates in a different way, but again I'm way outside my level of understanding.


Regarding you comment about Toyota not developing a proper range of BEV's - I didn't post this news from about a month ago, as folk (like me) are waiting to get the full story and Toyota's response, but a Norwegian car 'magazine' raised huge concerns about the range of the BZ4X after testing. Toyota Europe couldn't explain, so asked Toyota Japan to investigate. There are suspicions that the stated useable battery capacity figure, is actually the whole battery capacity, but there's also a chance that the reviewers just got a vehicle with a problem. Hence waiting for the full story / Toyota's response.

Grumpy_chap

Martyn1981 said:

Regarding you comment about Toyota not developing a proper range of BEV's - I didn't post this news from about a month ago, as folk (like me) are waiting to get the full story and Toyota's response, but a Norwegian car 'magazine' raised huge concerns about the range of the BZ4X after testing. Toyota Europe couldn't explain, so asked Toyota Japan to investigate. There are suspicions that the stated useable battery capacity figure, is actually the whole battery capacity, but there's also a chance that the reviewers just got a vehicle with a problem. Hence waiting for the full story / Toyota's response.

I actually went to look at the BZ4X when it was first launched and the sales representative claimed that the miles range was not affected by weather etc., but 310 miles was guaranteed under all conditions.  Now, I charitably at the time put this down to poor staff training.  It could be, of course, that the range is minimum 310 miles under worst conditions and most of the time would better that.  OR, it could be as is suggested by the comment above that the battery and range is quoted with a certain amount of "spin" by Toyota.

I guess, either way, the car has a 70-ish kWh battery so a long range should be expected.  However, if the gap between whole and usable capacity is top be deducted from the quoted figure, what does that mean?  About 65 kWh battery?

For various reasons, I was not that impressed by the car when I saw it as a suitable vehicle for my needs.  I think I put some notes higher up in this thread at the time.  However, my younger Brother has ordered one back in August and expects delivery in April, so we may have some feed-back on how the car performs in the real world if my Brother shares any details.  

Martyn1981

HI GC. Yes I recall you mentioning you'd gone to see it, but completely forgot you mentioning your brother*. At the time I think I said the stated range was OK (not good, a bit inefficient), but I was surprised at the max charging speed of 150kW, and more so the AWD which was 100kW, despite being less efficient. But, big BUT, that's not too bad, first world problems, just a bit low if you really wanted to 'splash and dash'.

Of course all this was overtaken by the issue of wheelnuts!

*I think I've made it clear that I'm extremely underwhelmed by Toyota, especially Mr Toyoda their Head, and Head of the Japan Automobile Manufacturers Association, when it comes to BEV's. But, this is their first real adventure into the modern BEV game (other than the RAV4 EV whose production ended in 2014), so mistakes will happen. Hence why I've been waiting with interest to find out what is (or isn't) wrong with the 'busyforks' and its range, but didn't post the news from just over a month ago.

However, if your brother is still getting one, then might be worth a read, but don't jump to any conclusions yet, and beware any dodgy translation issues:

Elbil24 article

Now it is finally ready to drive, and we have driven the car through our thorough tests, which also include our 100-0% range test, our consumption test, as well as our 0-100% charge test.

I can reveal that this is the very first time we have had to run the tests multiple times, as the initial results gave us results we hardly believed were true.

Actual range

To make a long drive very short, we finally rolled up to the charger with 0 kilometers of range remaining, which we just have to assume is also 0 percent, as a percentage display does not exist in the car. Incidentally, it is sorely missed among experienced electric drivers.

The field that indicated the distance traveled said that we had rolled 307 kilometers since we started, while the consumption meter said that we had used 1.91 kWh per mile.

[Note - I had do some checking on that 1.91kWh/mile claim, as it made no sense to me. It's a mistranslation from the article of 1.91kWh/mil, and that turns out to be 10km's (also confusingly, or jokingly known as a Scandinavian mile).]

BTW - My guess, and it's not a strong guess, would be that Toyota have set some overly harsh restrictions in the software, to protect the battery from overuse, or overheating when charging. So it may simply be that more is 'unlocked' as they gain confidence?

70sbudgie

I have been using the preheat function on my Zoe rather a lot in the last week. It is a lot easier to get the children out of the house if I'm asking them to go and sit in a warm car. I have noticed that it can use between 1kWhr and 2kWhrs. Obviously there is some benefit to preheating the batteries, but in these times of being conscious of each kWhr, do the benefits outweigh the cost? I am interested how many EVs have the preheat function, how much do people use it and generally what people think of it (other than the luxurious comfort!).

Grumpy_chap

Martyn1981 said:

HI GC. Yes I recall you mentioning you'd gone to see it, but completely forgot you mentioning your brother*. 

Of course all this was overtaken by the issue of wheelnuts!

However, if your brother is still getting one

Aaah, yes, I remember the wheelnuts being spun by some sectors of the press as an EV-issue when it was nothing of the sort.  

I saw the BZ4x when it was first launched (with the radio marketing campaign) and then found out a short while afterwards that my Brother had ordered one even though he'd not been able to see or test drive one at his local Dealership.  I suggested he popped into our local Dealership while visiting Mum to have a look-see.

I suspect my younger Brother will still go ahead with the car.  He has ordered it on an SS scheme through work with some "fudge" that means it will operate like a PCP rather than lease - others explained how this works (either here or the motoring forum) even though it is not how the SS schemes are meant to operate.  Being through an SS scheme, the cost to acquire should work out very favourably.

My younger Brother is quite different to me in that he doesn't have a house (and moans about renting) yet drives his way through brand new cars at a fantastic rate.  Flash cars would be nice, but I prefer my security of a (recently) mortgage-free house and can now choose to get a better car than the mostly-bangernomics approach that got me to this point.  

QrizB

JKenH said:

How far can you go in an electric car?

No spoilers, you have to decide if it’s worth reading with that title and me posting it.

https://www.autotrader.co.uk/content/news/how-far-can-you-go-in-an-electric-car

Wow, that's a long way - although at the speed they mention, it's also a long time!

JKenH

Drop in demand for electric cars as cost of living crisis bites

Auto Trader said EVs accounted for fewer than a fifth (19%) of new car inquiries sent to retailers through its online marketplace last month.

That is down from 27% in June.

https://www.standard.co.uk/business/business-news/drop-in-demand-for-electric-cars-as-cost-of-living-crisis-bites-b1046733.html

Grumpy_chap

JKenH said:

Drop in demand for electric cars as cost of living crisis bites

Auto Trader said EVs accounted for fewer than a fifth (19%) of new car inquiries sent to retailers through its online marketplace last month.

That is down from 27% in June.

https://www.standard.co.uk/business/business-news/drop-in-demand-for-electric-cars-as-cost-of-living-crisis-bites-b1046733.html

That may well be linked to the general media stuff about EV's now being expensive to run because electric prices have risen.
It is true, but petrol prices have also risen, so the comparison needs to be on current-day to current-day prices, not (as some media seem to compare) today's price for electricity and a previous price for petrol.
It still seems favourable as far as I can tell to go for an EV if only considering running (fuel / energy) costs.
Some can also benefit from reduced cost electricity (solar or free destination / workplace charging).

Costs to acquire a new EV remain high but I am sure will correct themselves.