Going Electric.. present small car options.. confusing

[Most Easterly Pandas]

A lot is being said about fast charging in just a few hours but I'm wondering, with most batteries, if you push high rates of charge into them they degrade much more quickly than if you "trickle charge" them. Does the same rational apply to these EV car batteries or are they completely different "animals" altogether?

Won’t cause an issue. At the end of the day a fast charger is 7kw.

The battery will have significantly higher draws in and out when driven under full acceleration or regenerative braking.

What does cause issues is high temperatures (not an issue on modern EVs as most now have active thermal battery management, but an issue with the Nissan Leaf which still doesn’t) and leaving the battery at very high or low states of charge for extended periods of time when not needed.

 

[StevenRB45]

Not sure I’ve seen the E-Golf being capable of 180 miles however.

There was a later version that came out shortly before the car was canned to make way for the ID3 that had an official 180 mile range and is meant to do about 150 real world.

 

[Didge3]

A lot is being said about fast charging in just a few hours but I'm wondering, with most batteries, if you push high rates of charge into them they degrade much more quickly than if you "trickle charge" them. Does the same rational apply to these EV car batteries or are they completely different "animals" altogether?

I also came across an article about electric cars where someone was saying they would charge the battery fully whenever they returned to home regardless of whether they might use the car within the next day or so or not. The author of the article was pointing out that it's not good practice to do this - fully charge the battery and then not use it for some time - and it's much better practice to let one of these batteries stand at part charged, which I seem to remember being the recommendation for the Li-ion batteries that came with my boy's new drill?

By most batteries are you referring to lithium batteries in phones/laptops etc? Whilst in principle they are the same tech as an EV traction battery a phone battery is usually just 1 cell, laptops 3-6 depending on size. An EV has upward of 100 cells, my car has 288 individual cells. Charging is split evenly across these cells so where charging a 1 cell phone at 18W (most modern phones are capable of this and seems to be the standard) an EV is splitting that 7kW by its number of cells resulting in not a lot of stress on each cell.
Rapid charging can see upwards of 100kW dependant on the cars capability, this is where you're likely to stress a battery, 7kW or even 22kW at a fast charger isn't going to hurt it.

As for storing at a full charge it kind of varies from manufacturer to manufacturer, some advise (Tesla and I think Hyundai) you charge to 80% (this can be set in the car to automatically stop the charge) unless you need the full 100% range. Others like BMW tell you to always charge to full and leave it plugged in.
This is another difference from phone/laptop batteries where EV's don't actually charge to 100%, a lithium cell at full charge is around 4.2v, an EV will typically charge to something like 3.9v and report that as 100%. This prevents some of that degradation that occurs at a high state of charge.

 

[AndyRKett]

By most batteries are you referring to lithium batteries in phones/laptops etc? Whilst in principle they are the same tech as an EV traction battery a phone battery is usually just 1 cell, laptops 3-6 depending on size. An EV has upward of 100 cells, my car has 288 individual cells. Charging is split evenly across these cells so where charging a 1 cell phone at 18W (most modern phones are capable of this and seems to be the standard) an EV is splitting that 7kW by its number of cells resulting in not a lot of stress on each cell.
Rapid charging can see upwards of 100kW dependant on the cars capability, this is where you're likely to stress a battery, 7kW or even 22kW at a fast charger isn't going to hurt it.

As for storing at a full charge it kind of varies from manufacturer to manufacturer, some advise (Tesla and I think Hyundai) you charge to 80% (this can be set in the car to automatically stop the charge) unless you need the full 100% range. Others like BMW tell you to always charge to full and leave it plugged in.
This is another difference from phone/laptop batteries where EV's don't actually charge to 100%, a lithium cell at full charge is around 4.2v, an EV will typically charge to something like 3.9v and report that as 100%. This prevents some of that degradation that occurs at a high state of charge.

All a valid point. If you take something like your car the battery is quite small something like a Tesla has upward of 7000 cells. So if you push 100kw into a 7000 cell battery it only equates to about 14w per cell, it’s just all that power generates a lot of heat so the thermal management becomes important. You can get some worrying noises with high powered fans running at high charge rates on electric cars.

But in essence, the batteries don’t actually get massively stressed even at high charge rates.

 

[Didge3]

All a valid point. If you take something like your car the battery is quite small something like a Tesla has upward of 7000 cells. So if you push 100kw into a 7000 cell battery it only equates to about 14w per cell, it’s just all that power generates a lot of heat so the thermal management becomes important. You can get some worrying noises with high powered fans running at high charge rates on electric cars.

Tesla batteries are a bit different compared to the majority, maybe the higher number of smaller cells is specifically to allow faster charging?
A model 3 LR has approx a 75kWh battery
A 2020 Kia Soul 62kWh has 294 cells
A Nissan Leaf 62kWh has 288 cells
A Renault Zoe 50kWh has 192 cells
Don't cell shame my Ampera!
It's got a similar number of cells to many EVs just they're a much lower density as a result of being 11 year old tech

 

[Pugglt Auld Jock]

Hmm. The above conversations make me reflect that:

1) An awful lot of us - the general public - as yet, know next to nothing about how to properly treat this new technology. I think it would be best if the manufacturers build then so they can't be damaged by ignoramuses - like me. I'm sure they could invent controlling programs which would do this?

2) I'd assumed, in my naive ignorance, that electric cars were going to be much more simple - no IC engine, no complicated gearboxes, no fueling system, etc, etc. However the more I read the more I learn that they are full of complicated electronics which, whilst probably more reliable than the old technology, is going to be unfixable by the likes of us and could cost plenty to fix. Also I'm learning there's now to be lots of other ancillary "stuff", like these battery cooling systems, so the "simplicity" argument seems to be rapidly disappearing down the drain.

So what I feel at this time is: a) Considerably more expensive to buy. b) Much will be "untouchable" for driveway mechanics like me so running costs are going to rise compared to me looking after our present cars. c) Big learning curve for us to go up in terms of how we use them with fueling, range for stuff like annual holidays etc, problems with accessing charging when away from home, The list goes on. No doubt all this just requires dinosaurs like me to think outside our little boxes though and the problem won't exist for the next generation because they will grow up with it!

Finally they cost a lot more, are going to be less durable - what's a 20 year old one going to be like (that's the age a lot of my cars get to - or thereabouts, some older - before I give up on them) and the batteries seem to be using up quite large amounts of rare and polluting ingredients - I saw they are to be mining the sea bed because they can't find enough of the stuff on land? Hey, this is an interesting subject about which I know very little compared to my knowledge of IC powered vehicles. Now there's a good subject for my personal research. Think I might try to get a test drive in one just to get a close up look and see what the experience is like - For sure I'm going to be doing a lot more "digging". Anyone care to suggest a particular vehicle for my test drive?

 

[AndyRKett]

They are well kitted out with control systems to prevent the owner/driver from causing damage, certainly no more than someone could with an internal combustion engine.

The technology is simple. Battery, motor, switch. The complication comes from adding in the control systems to make it safe, controlled and also robust. The large motor and battery could send you flying down the road a scary fast acceleration (the lastest model S Tesla has a sub 2 second 0-60) so they want normal cars to drive and feel familiar to regular users.

This technology is very simple but if you’re not an electronics engineer then no it’s probably beyond fixing yourself... at the moment. But as time goes buy the information will be out there for people to work on their own cars, it’s however unlikely that you’ll need to other than maybe brakes and suspension type problems.

The battery is not something you can work on, the motor is not something that you’ll be able to or need to work on. The electronics are not really that far removed from all the electronics in any other car. So there is honestly nothing mysterious about them. As far as longevity they should last longer than normal cars as engines(motors) won’t wear out, people will not be as concerned with a 100,000 mile electric motor as far less moving parts and little to wear.

This is why people are still paying thousands of pounds to keep there Nissan leafs from 2011 on the road or have the battery upgraded because they just keep going and need very little input.

They don’t even really require any servicing just an annual inspection and grease anything that doesn’t move like it should.

Yes they are expensive at the moment. We’re currently in a transition but prices will drop, I don’t think they will drop that much because firstly cars have become too cheap and manufacturers are struggling to keep in profit, and secondly these cars will last longer so people will not replace them as often

 

[Most Easterly Pandas]

Tesla batteries are a bit different compared to the majority, maybe the higher number of smaller cells is specifically to allow faster charging?
A model 3 LR has approx a 75kWh battery
A 2020 Kia Soul 62kWh has 294 cells
A Nissan Leaf 62kWh has 288 cells
A Renault Zoe 50kWh has 192 cells
Don't cell shame my Ampera!
It's got a similar number of cells to many EVs just they're a much lower density as a result of being 11 year old tech

Soul is 64kWh

I'll get my coat

Hmm. The above conversations make me reflect that:

1) An awful lot of us - the general public - as yet, know next to nothing about how to properly treat this new technology. I think it would be best if the manufacturers build then so they can't be damaged by ignoramuses - like me. I'm sure they could invent controlling programs which would do this?

2) However the more I read the more I learn that they are full of complicated electronics

So what I feel at this time is: a) Considerably more expensive to buy. b) Much will be "untouchable" for driveway mechanics like me

1) How many other than us petrol heads actually know how to properly treat an ICE car? Not many IMO. Most just use them as an appliance to get from A-B.

2) Current ICE vehicles are also full of complicated electronics. None of which you
touch as a driveway mechanic. You'll just have just of the normal servicing stuff to do. I cleaned up the brakes on my Soul EV on the drive, still some jobs to do

 

[Pugglt Auld Jock]

Soul is 64kWh

I'll get my coat



1) How many other than us petrol heads actually know how to properly treat an ICE car? Not many IMO. Most just use them as an appliance to get from A-B.

2) Current ICE vehicles are also full of complicated electronics. None of which you
touch as a driveway mechanic. You'll just have just of the normal servicing stuff to do. I cleaned up the brakes on my Soul EV on the drive, still some jobs to do

On your No 1 I think you are absolutely right.

On your No 2 I'll have a go at most "stuff" except Electronic control units themselves which I would send to someone like ECU Testing or BBA Reman for checking out after I'd tried everything else. I also have a problem with Can Bus in that I think I understand the concept behind it but don't really know how to fault find effectively - I've seen the mirrored waveforms but it's all a bit of a mystery as to what it's telling me. Sensors, actuators, relays, etc and, very often, continuity of wiring I'm relatively "happy" messing about with.

 

[Didge3]

I think one of the bigger constraints on EV servicing is not the owner servicing themselves but the dealerships! You'd be surprised at how many main dealers simply don't want to touch an EV even though they sell them...
A true story from around 6 months ago a MG ZS was dropped off at the MG dealership it was originally purchased from to get a software update. The owner went to collect the car at the end of the day and they said the car hadn't been looked at yet. Obviously owner somewhat annoyed given they had booked the car in asked why and they were told the car had to be left for at least 2 hours before they could open the bonnet because of the high voltage electricity!
Now I would hope they genuinely didn't actually think that was the case and were rather making an excuse as to why it hadn't been done but not what you expect from a main dealer. These are the professionals who we are supposed to trust and if an owner was none the wiser could now be scared of actually opening their bonnet in the future for no reason. Admittedly this is the most extreme example I've heard but it is far from the only time a dealership hasn't had a clue when diagnosing issues with EVs.
VW are having a lot of issues with the software on its ID.3s, the dealerships had no idea what to do when they first started coming in with bizzare issues, ultimately there wasn't anything they could do until VW issued a software update but an average owner wouldn't be best pleased taking their car in and being told we don't know.

 

[varesecrazy]

Servicing knlowledge will take time..
The fella who my employer got in to show us 'the basics'.. on 400+V systems

Said he often attends dealerships.. and fault finds in a matter of minutes

Coats in rear footwells blocking airflow
Battery temp rises.. alarm on dash

He bills £500 for the days call..

you would HOPE things get understood fairly quickly..

But looking how many ECUs still get swapped needlessly .. I am not so optimistic

 

[Most Easterly Pandas]

Well the EV specific side of things simply don't need servicing. At the moment so little goes wrong with them even their basic training they should be able to cover most issues. Dealers need to buck up their ideas quickly otherwise they'll soon be bust without seriously modifying their business models for servicing.

Kia has it right IMO, £69 and £89 for a Minor / Major service on my Soul, reflects what little they do, IE no oils and filters to change. Nissan on the other hand iirc £150 and £300 for minor / major. And they do nothing differently on the Leaf to what my dealer does with my Soul.

At the prices I pay I don't mind sticking with the main dealer to get a stamp in the book, I mean £99 for MOT and service I can't moan at when some places charge of £50 for the MOT alone.

VWs issue was releasing a car before it's been fully designed and built, and more fool anyone that was silly enough to buy one knowing this - it's been very well documented before they even hit the UK!

 

[AndyRKett]

VWs issue was releasing a car before it's been fully designed and built, and more fool anyone that was silly enough to buy one knowing this - it's been very well documented before they even hit the UK!

This is only half the story. At the moment and in the last couple of years there has been a explosion is the technology that's out there, everything from home smart devices which didn't really exist 6-7 years ago, to cars having smarter and smarter technology as well as machine learning and now even a basic kettle has some sort of smart tech in it.

As a result when VW turned there entire R&D efforts over to electric cars after the Diesel gate scandal they where seriously lacking the people they needed to develop software for cars they had never made before.
This is why the software on the ID cars has been so lacking, At one point VW were offering 6 figure salaries to anyone who remotely knew how to program a line of code, which in turn probably lead to them employing substandard programmers and then chasing their own tails(bugs) cars sat built but unable to deliver for ages till they could get things more usable and as time is going by they are beginning to get things in order.

Other companies probably developed a lot more R&D time and resources over a much longer period to getting things in order, like the soul being around for years, also Nissan and other companies playing about with at least 1 electric car model for a longer period. VW jumped in with both feet and found they didn't really know how to swim in that pool.

Even now if you work in programming/coding and you've got even a sligh idea what you're doing and you can show off your skills then you can easily find a well paying job.

 

[DaveMcT]

A big problem for legacy car builders is their "parts bin". They have boxes for everything that do the job and were bought at low cost. Fiat have done extremely well with the "if its not broken" philosophy. The snag now is those benefits are not translating well into EVs. The multiplicity of boxes with ordinary fuses and huge wiring systems are creating failure points and hence warranty issues and costs for future owners. The VW ID is extremely well built but the under bonnet is stuffed with stuff. The clean sheet approach at Tesla allowed far more efficient use of space and hopefully better reliability.

Check out this from Sandy.

https://youtu.be/ZRkm6-bBk4U

 

[DaveMcT]

I think brakes will become problems for electric cars. They get far less use than in an ICE car so corrosion will be a problem not found in ICE cars. The iron discs may well have to be moved to stainless with aluminium calipers and maybe stainless liners to avoid the galvanic corrosion that bedevils many motorbike brakes. I personally think there is a good place for Citroen style mineral oil based hydraulics but traditionalism within the industry will focus on 1980s problems and ignore the benefits.

 

[Most Easterly Pandas]

I think brakes will become problems for electric cars. They get far less use than in an ICE car so corrosion will be a problem not found in ICE cars. The iron discs may well have to be moved to stainless with aluminium calipers and maybe stainless liners to avoid the galvanic corrosion that bedevils many motorbike brakes. I personally think there is a good place for Citroen style mineral oil based hydraulics but traditionalism within the industry will focus on 1980s problems and ignore the benefits.

I’m not so sure. While there have been some issues, with the way most people drive they’ll get enough use to keep them ticking over. The issue will likely be with those doing very few miles and / or driven so well that the friction brakes get little use.

The odd hard hit should be enough to keep them going well, and tbh I’ve had some normal cars sit for extended periods of time and never had to change brake disks due to corrosion etc.

 

[DaveMcT]

Hopefully friction brake disuse wont be an issue. I raise it because the back discs on my Citroen BX would be pitted long before they wore out. The self levelling suspension put most of the braking demands on the front end. That rears hardly did anything. They were especially vulnerable, because the hand brakes worked on the front axle.

Long term, we might see low cost individual motors on all wheels providing power and braking. Outside the legal demands, there might be no need for mechanical brakes.

 

[StevenRB45]

Hopefully friction brake disuse wont be an issue. I raise it because the back discs on my Citroen BX would be pitted long before they wore out. The self levelling suspension put most of the braking demands on the front end. That rears hardly did anything. They were especially vulnerable, because the hand brakes worked on the front axle.

Long term, we might see low cost individual motors on all wheels providing power and braking. Outside the legal demands, there might be no need for mechanical brakes.

Maybe that's just a Citroën set up thing, rear brakes on the C3 look like I found them on the bottom of the sea...it's done 15k miles I fully expect them to need changing shortly.

Possibly something to do with it weighing slightly over 1000kg but having rather large brakes. None turbo has drums on the back but has reasonably meaty vented discs on the front and solid discs rear which clearly do very little day to day.

When I get the new set must remember to pull the handbrake while moving occasionally.

Heavier Mazda rear discs are original after 10 years and 86k.

 

[AndyRKett]

Maybe that's just a Citroën set up thing, rear brakes on the C3 look like I found them on the bottom of the sea...it's done 15k miles I fully expect them to need changing shortly.

Possibly something to do with it weighing slightly over 1000kg but having rather large brakes. None turbo has drums on the back but has reasonably meaty vented discs on the front and solid discs rear which clearly do very little day to day.

When I get the new set must remember to pull the handbrake while moving occasionally.

Heavier Mazda rear discs are original after 10 years and 86k.

I think the way that old hydro pneumatic suspension worked it would always load up the front wheels, and push the back up.

Rear brakes really only aid stability the hard work is always done at the front but newer cars are all much heavier than they were in the 80s and 90s.

I’m not sure why anyone would compare something like an old Citroen from the 80s to a new electric car

 

[StevenRB45]

I think the way that old hydro pneumatic suspension worked it would always load up the front wheels, and push the back up.

Rear brakes really only aid stability the hard work is always done at the front but newer cars are all much heavier than they were in the 80s and 90s.

I’m not sure why anyone would compare something like an old Citroen from the 80s to a new electric car

God knows..

I'd imagine the reason for the ones on the current Citroën is to do with weight distribution fairly good chance on something that size with turbo and ancillaries under the front it's pushing at least 60/40 weight distribution. The fronts are actually surprisingly heavily worn for their miles so wouldn't be surprised if they did 90% of the work.

Electric car though the weight distribution is unlikely to be as uneven so if it needed friction brakes they could be set towards more rear bias than a conventional vehicle as the rear should have a bit more traction.