EV general discussion

[b0rn2sk8]

Wonder what the practical limit is on charging power? We can manage 350kW already, so there may be more to come in time?

Tesla's Megacharger concept is supposed to be aiming for a MW or more, but that's for a truck.

One you start getting up to those sorts of numbers there are so many other factors to take in like needing on site energy storage to level out all the spikes of the chargers turning on and off.

The higher the load you intermittently put on the grid, the more expensive those KWhs become to service.

 

[Mercenary Keyboard Warrior]

You are miss interpreting it. You have stated I'm thinking we shouldn't progress. I have offered maybe that its the opposite and in turn offered some thoughts about battery thermal management

No need to get upset. Pretty clear that OEMs need fluids specific to cooling a battery... and work on cars of the future right now. What do you think Formula 1 batteries have to stay cool? Its not air cooling, you need to take heat away from the battery from inside, obviously water would be the best fluid for this, but it doesn't mix with electrons too well. Having a fluid cooling medium also increases the surface area you can interact with to take heat away, aswell as effectively turning the battery into many many cells rather than one pack. This is the way OEMs are going to manage thermal challenges. Not split the battery up in the car but split the battery up within its existing footprint (maybe a 5% increase for cell spacing)

So your original problem was right and solution was viable, but its not the way to industry have chosen to address it. Direct cooling is what the Porsche Taycan is using, which is why its a step change in terms of sustained performance and charge time.

I'm not getting upset and It wasnt me who brought up the battery cooling issue, so im not sure why this is even an issue, I know what they are doing and if you split the battery "pack" into two equal sizes and put them in two places at that scale its unlikely to change the heat issue at all. My point was that there is an increase in flexibility to distribute the batteries in the foot print than an ICE, its there even now already done, just right now that tends to be one point thats still in most cases really just influenced by ICE design, since the cars are ICE designed and converted into Ev design.
If you want to change the layout to use the same footprint as a now you can do it more efficiently or more creatively than with ICE. Move the engine in an ice car to the middle or back and we know it gets harder to cool, plus the hear from a mid engine is very very difficult to stop penetrating even separate cabins let alone if it was one large cabin.

Using a liquid is ideal, its not only a great mechanism to move the issue its also a good store as well, unlike heat to air be that active or passive the fact the liquid acts as a radiator means its dampening the spikes and the benefits that brings, such as if there is a detectable issue it gives time to react. I know you know this, just saying. Of course in the winter its likely you can benefit from this liquid being heated since its useful for preheating the batteries and interior, again youve added an energy store into the vehicle.

Im just thinking if you took a small people carrier size vehicle, and were able to have almost all that space available it would bring different options compared to the current one thats based on having an engine at the front, then 2 or 3 rows of seats.
You could be far more flexible in that configuration, particularly if you get to the point of not actually needing a driver.

Anyway appreciate your input, even though it may not come across that way

 

[[TW]Fox]

the petrol is a chore.

But why?

 

[jpaul]

Direct cooling is what the Porsche Taycan is using

... googles not telling me - what do they have versus a model3, fluid that is closer to the batteries ? ... PCB's would have been good.

The 800V of the teycan, seems to somehow help with faster charging ... why is that
I guess, the batteries internally, are more in series, than parallel, so they have a higher combined voltage, but the charger itself isn't negotiating a higher voltage (versus a model3), or is it ? I though 600V was the maximum.
if the charger is providing 800v, then obviously you'd be able to take a lower current through the (regular) charging cables, which presumably have the necessary insulation,
and, the plugs are ok when it's raining.

 

[jamoor]

But why?

As I said, you will never know how a car is to drive until you drive it yourself.

 

[[TW]Fox]

As I said, you will never know how a car is to drive until you drive it yourself.

You won't know what its like to 'live with an EV' until you actually buy one. Which is quite the commitment to make on the basis of someone on the internet saying it's fine.

That said I don't need to actually buy an eGolf to know it'll stop in the outside lane of the M5 if I try and drive it to Heathrow non stop.

 

[jamoor]

You won't know what its like to 'live with an EV' until you actually buy one. Which is quite the commitment to make on the basis of someone on the internet saying it's fine.

That said I don't need to actually buy an eGolf to know it'll stop in the outside lane of the M5 if I try and drive it to Heathrow non stop.

Any car will stop if it runs out of fuel...

oh and you can buy a Tesla drive it for a week Or 1,000 miles and return it no questions asked! See if it works for you

 

[[TW]Fox]

Any car will stop if it runs out of fuel...

But the car I drive has enough fuel to get me from my house to about Perth in Scotland (My personal record) before they do that...

Cars with short range - whatever the reason - are frustrating. It's one of the major issues that puts me off a 530e, for example. Who put a 40 litre fuel tank in a 2 litre petrol turbo? Great...

 

[jamoor]

Yeah if you’re driving From one end of the U.K. to the other regularly then I guess an ev isn’t for you. For 99% of the population who do on average 27 miles a day it’s much more suited.

 

[Vita]

I actually prefer hybrid at the moment. Use a little electric around town and for the longer journey you have the petrol.

I am interested in EV but I don’t think it’s viable at the moment for my needs.

 

[[TW]Fox]

Yeah if you’re driving From one end of the U.K. to the other regularly then I guess an ev isn’t for you. For 99% of the population who do on average 27 miles a day it’s much more suited.

As I say I'm not anti EV - infact the only reason I'm not ordering an Electric Mini is because we've only just bought a petrol one - but for many people they just don't work yet. It would be more hassle than its worth for my car use.

 

[Jonnycoupe]

OK i get it those cables cant be used for anything else.
So we do have HV cables in teh car, if only someone could think how to utilise them to spread out the batteries abit.

But nope we have already reached the end point.
We already have optimised, battery density, cooling, distribution, vehicle layout etc
Its job done no need to change anything at all

That was the e-Golf and not even to the extreme you have described with a odd shaped module array in an existing body. VW has had to the thought to go to a new MEB EV platform, centralised uniform battery pack for the ID range of cars citing price parity on the ID3 with a golf around 2025. I think that gives enough clue of the elegant way to do it.

 

[Jonnycoupe]

Jesus not as the only source of cooling no, and possibly never.
But its easier to cool something with a larger surface area than a smaller one.
However that could be detrimental in the car world i agree, ie more heat leakage

The surface area you refer to is a liquid to air heat exchanger. It automotive terms thats a radiator or condenser.

 

[Jonnycoupe]

You've got to pull into a Tesla supercharger area too though?

I'm specially angling at people who do long trips here. If I only do local running around a tank of fuel lasts a month anyway so time taken to fill is an irrelevance when it's so infrequently done.

I don’t think that’s the everyday/week event though. The point is you can do that at home with an EV once you park for the evening 95% of the time.

 

[Jonnycoupe]

... googles not telling me - what do they have versus a model3, fluid that is closer to the batteries ? ... PCB's would have been good.

The 800V of the teycan, seems to somehow help with faster charging ... why is that
I guess, the batteries internally, are more in series, than parallel, so they have a higher combined voltage, but the charger itself isn't negotiating a higher voltage (versus a model3), or is it ? I though 600V was the maximum.
if the charger is providing 800v, then obviously you'd be able to take a lower current through the (regular) charging cables, which presumably have the necessary insulation,
and, the plugs are ok when it's raining.

current is halved, less heat. For charging it splits the pack into two 400V modules so if each take 130kW you have 260kW charging. Then after charging just close the HV contactor bridge to bring 800V online and off you go.

warm cable? Just water cool them. Sorted.

EDIT: must work on my multi quite use!

 

[Russinating]

There are so many benefits to EVs I can't understand why you're trying to cling to the how amazingly convenient having to stop and charge for half an hour is versus a quick petrol stop. Because thats one of the few obvious drawbacks. Filling up with petrol isn't a chore, doesn't take very long and isn't done very often unless you drive a V10 M5. It's just not an issue, so the EV is never going to win the how long it takes to fill up argument.

Pick one I can't argue with, like the smoothness and refinement around town or something.

Or the zero company tax which is the real reason why everyone suddenly wants one

I know what you mean - it's not a benefit as such - it's more that the drawback isn't as severe as people think it might be. Who's not stopping for a break on a 7 hour drive anyway for example? They're pretty well placed as well (Tesla this is) that stops are often at the half way point or thereabouts.

It's reducing a negative, rather than creating a positive.

 

[jamoor]

As I say I'm not anti EV - infact the only reason I'm not ordering an Electric Mini is because we've only just bought a petrol one - but for many people they just don't work yet. It would be more hassle than its worth for my car use.

You can probably pick one of those up cheaply in a few years as the residuals will be terrible imo.

 

[Mercenary Keyboard Warrior]

That was the e-Golf and not even to the extreme you have described with a odd shaped module array in an existing body. VW has had to the thought to go to a new MEB EV platform, centralised uniform battery pack for the ID range of cars citing price parity on the ID3 with a golf around 2025. I think that gives enough clue of the elegant way to do it.

Thanks I hadn't heard of it, and boom exactly what I was envisioning the batteries spread across the whole floor rather than all stacked up (in effect) in a small area.
And a nice base plate with cooling system right at the bottom thats really quite impressive.

So its seems the ID Buzz was what I was really sort of thinking about, never heard of it before but sounds really interesting
That would make a wicked camper

 

[ianh]

Nope, not yet, touch wood. I'm sure I will - not because of EV, just idiots gonna idiot. I generally only charge overnight so it gets plugged in at ~11pm and unplugged at ~7am, with a security light and camera looking on it, and Sentry Mode enabled on the car. Most people I catch on cam are just interested and curious. Cable is locked into the car so all anyone could do would be to unplug it from the wall which would technically be trespassing as well.

When I'm in Stoke I live in a particularly "scroate central" part so I'd always be worried about someone either just unplugging it from either the car or house (don't know if it possible) because they're being stupid or, more worryingly, some moron trying to damage the cable for "reasons" - yeah, some parts of Stoke are fun

Driveway charging seems to be a much better way of dealing with EV's but we can't all live in houses with driveways so on-road charging of Terraces and Flats (currently 30%+ of all housing) is something that will need a really serious thinking about from the power that be if they want 100% EV by 2050.

 

[Nasher]

There was an incident a few years ago where someone stuffed cream eggs in to charging sockets. Which made them unusable.

This kind stuff will become more common in future.