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Discussion Starter · #1 ·
Well, does size really matter?
Is big really not best and is a smaller one used more often a better choice?

Good guidance for choosing battery size for your EV needs are few and far between and are in my experience, rubbish.

There are no rules of thumb i can find either and any attempt to guage battery requirements ignore OEM requirements or usage patterns or degredation.

I am 2 months in with EV ownership. I couldn't afford a 80+kw battery so had to settle for a 60ish kw version instead.

The experience has been enlightening.

Not only do i not need a bigger battery, but the smaller battery is both better for the car and the environment (and my wallet).

I think that a rule of thimb is that your battery should give you twice the range of either your high daily median mileage or your singular long distance trips if they are are your norm.

So, if you do 3000m pa and your car is parked up for most of its life, just get the smallest battery version of the car you are considering. For the odd long trip, get used to the public charging network,

If you do 30000 miles a year by frequently using the car on medium trips, again buy the smallest battery that fits the above rule of thumb. A 60kw battery can easily give you a annual mileage of 30k.

Big batteries are only needed for high power usage between charging. For example:
  • If you are time sensitive and do long distance.
  • You have no private charging capabilities and can only use public chargers.
  • You live in a region which requires high power for heating/cooling.
*Your name is Nigel Mansell.
 

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i agree i have a ZE40 and i want a ZE50 but another £5-10k for extra range i wont use seems a bit pointless however here is where the man maths kicks in.......(try and convince myself due to CCS etc)
 

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I agree and disagree. I have the enyaq 60 as I couldn't stretch to the 80. The longest journey I frequently do is Manchester to Central Scotland - 220 miles - which is a smidge outside the range I can get from the car. So far no technical issues besides passengers huffing that we have to stop for 20 minutes for a quick top up. Though if I could do the drive without charging it would make my life easier, so the larger battery would have been welcome.

But for typical use the 60 is plenty as a single charge per week is sufficient.

Given the current charging services at motorways I can see this might change as queues get longer and chargers get busier. We'll see I suppose!
 

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Discussion Starter · #4 ·
i agree i have a ZE40 and i want a ZE50 but another £5-10k for extra range i wont use seems a bit pointless however here is where the man maths kicks in.......(try and convince myself due to CCS etc)
My post is poorly worded, but it makes valid points.

I'm doing 4000km per month on a small battery with the odd 500km round trip and i have zero problems at the moment.
I think as the public charging stations get real (as in become deliberate rather than an add-on) then range issues will just stop being problematic.

The cost differences are not insignificant,, especially when you cross grant boundaries. you can be looking at many 000's £ for something you don't need and additional weight and manufacturing which is not needed. EV's are supposed to be for the enviroment.

also, it isn't just the price delta, you need to factor in interest rates on that addition as well,
 

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Discussion Starter · #5 ·
I agree and disagree. I have the enyaq 60 as I couldn't stretch to the 80. The longest journey I frequently do is Manchester to Central Scotland - 220 miles - which is a smidge outside the range I can get from the car. So far no technical issues besides passengers huffing that we have to stop for 20 minutes for a quick top up. Though if I could do the drive without charging it would make my life easier, so the larger battery would have been welcome.

But for typical use the 60 is plenty as a single charge per week is sufficient.

Given the current charging services at motorways I can see this might change as queues get longer and chargers get busier. We'll see I suppose!
Good example.

Your battery is perhaps on the small size for regular trips of that distance, although doable, the bigger battery would be better. If you are getting week out of a charge, then you've the right size battery imho and it shows just how good battery technolgy is now.
That said, 220 miles in one run is impressive. A mid way toilet/coffee break isn't unreasonable for that distance and 20 mins to get you over the line is not a big sacrifice.
 

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My Ioniq with 38 kWh useable battery can do 200 miles easily in summer, and also in winter going gently. The much larger and heavier Ioniq 5 just-about does about 20 miles more if you opt for the 58 kWh battery that's 50% bigger! So you have to go for the massive 72 kWh one to get significantly better range. I'm seeing mention in here of 3.something_small miles/kWh for this latest & greatest offering, while I & others manage 4.7 easily in the small-but-nimble original coupe.

There's a lot to be said for a small, lightweight & aerodynamic EV over the large clunky SUVs & smaller-but-still-clunky Crossovers. :)
(I'l get my tin hat ready for the barrage coming any moment now ...)
 

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Well, does size really matter?
Is big really not best and is a smaller one used more often a better choice?

Good guidance for choosing battery size for your EV needs are few and far between and are in my experience, rubbish.

There are no rules of thumb i can find either and any attempt to guage battery requirements ignore OEM requirements or usage patterns or degredation.

I am 2 months in with EV ownership. I couldn't afford a 80+kw battery so had to settle for a 60ish kw version instead.
If your BEV was efficiently designed you wouldn't need such big batteries, 50kw is plenty for medium range, 250 miles, 75kw is all you need to do up to 360 miles. I can think of at least one brand that can manage this.
 

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Good discussion. The magic 200 miles seems to be forcing manufacturers to release models that are enormously heavy. Coming from a 24kWh Leaf and doing about 5000 miles a year, I wrestled between a newer (much) larger battery but the weight and overall drive experience of most cars felt poor. Settled on 40kWh Leaf for the next 2 years, by which time we should see some more compact, ground up designed, properly efficient options.
 

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I also can't understand the obsession with SUV style cars, they just aren't aerodynamic a fundamental requirement for motorway driving efficiency. Slab fronted and slab backed vehicles have the aero efficiency of a brick yet the majority of manufacturers offerings are these. I'm sure something like a Skoda Octavia Hatchback which surely must be a better shape would sell like he proverbial hot cake, what do we get the chunky Enyaq !
 

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It is the same as the big engined ICE cars really but of course moving to BEV one is less sure until you have had the onwership experience. I did not want an SUV I wanted an estate, all that was on offer was an SUV which is a beast of a thing weighing 2555kg therefore to meet the magic range it has a large battery and as yet there is no choice in the range. I am pleased with it’s efficiency ie it does what mercedes say it will but efficient it is not and that needs addressing in the future.
I am generally only charging it to 50% using 20% in my normal day to day trips before charging it again usually every other day sometimes everyday depending on diary. So I agree in my day to day life a smaller battery would be fine. My medium trips do need more charge up to 80% charge but that will allow me to get there and back. I am avoiding thus far public charging but I will need to get to grips with it soon. Maybe a 65 or 70kwh battery would be ok not the 80kwh it has. Mercedes will no doubt learn from all the data they are collecting from the car and adjust things in the future but the OP comments have merit.
In essence when buying a BEV car you need to look at your normal mileage, how you will charge and then you can decide. The long rare trips will just need planning and if you are not a person who normally stops a bit of adjustment. Those of us who do like a regular wee and coffee break to refill for the next wee stop🙄 wil I think see hardly any travel time difference it certainly seemed that way when I checked timings on my last long trip in my ICE e class.
 

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I also can't understand the obsession with SUV style cars, they just aren't aerodynamic a fundamental requirement for motorway driving efficiency. Slab fronted and slab backed vehicles have the aero efficiency of a brick yet the majority of manufacturers offerings are these. I'm sure something like a Skoda Octavia Hatchback which surely must be a better shape would sell like he proverbial hot cake, what do we get the chunky Enyaq !
I want a passat estate sized ev. I went for the enyaq as I needed the boot capacity for camping and work. But no estate with large enough boot available yet, I had looked at the MG models. Totally agree on the pointless SUV styling dragging down efficiency.
 

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Discussion Starter · #12 ·
I also can't understand the obsession with SUV style cars, they just aren't aerodynamic a fundamental requirement for motorway driving efficiency. Slab fronted and slab backed vehicles have the aero efficiency of a brick yet the majority of manufacturers offerings are these. I'm sure something like a Skoda Octavia Hatchback which surely must be a better shape would sell like he proverbial hot cake, what do we get the chunky Enyaq !
The C.O.D. of the Passat estate is 0.3
The C.O.D. of the Enyaq is 0.28.

The design of the Passat is stuck in an era where cars were styled to be long and low to aid aerodynamics and to mitigate the long bonnets and wheel overhangs required for horizontal mounted engines. Power unit size was constantly under pressure to be as small as possible to reduce weight and emmisions.

The EV suffers none of that.

Wheels are in the corners of the vehicle where they should be. Powerplants are now modular and can be spread throughout the vehicle floorplan.

High speed travel is becoming less important as speed limits are becoming more rational and roads busier. The Autobahn in Germany is the only place where high power. Low slung vehicles have any justification.

Because the old design considerations have been eliminated with EVs, they are free to explore what a car really should be, which is, ultimately, practical and efficient.

The Enyaq has a better COD than its outdated predecessors. It has much better practicality. Its space footprint is more efficient due to its height and it is far, far easier to enter and exit with its higher roof line. It doesn't need a huge powerplant to move it as electric motors have a substantially better torque and power range than any ICE.

The design basis for cars has utterly changed. The old rules are in the bin.

New EV cars should look nothing like old ICE cars. It is a bugbear of mine atm that some manufacturers are still stuck in the past ICE mould.

If you want to see the future for EV car design, look at the Citroen Ami for clues. Highly practical and a design not handicapped by speed considerations alone.

SUV is a bad name. There is nothing "Sports" about these cars. They are just General/multi purpose vehicles designed as such.

As i get older, my days of contortionist flexation to get into the previous generation of "Cars" is over. Give me a "SUV" access profile anyday.
 

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The C.O.D. of the Passat estate is 0.3
The C.O.D. of the Enyaq is 0.28.

The design of the Passat is stuck in an era where cars were styled to be long and low to aid aerodynamics and to mitigate the long bonnets and wheel overhangs required for horizontal mounted engines. Power unit size was constantly under pressure to be as small as possible to reduce weight and emmisions.

The EV suffers none of that.

Wheels are in the corners of the vehicle where they should be. Powerplants are now modular and can be spread throughout the vehicle floorplan.

High speed travel is becoming less important as speed limits are becoming more rational and roads busier. The Autobahn in Germany is the only place where high power. Low slung vehicles have any justification.

Because the old design considerations have been eliminated with EVs, they are free to explore what a car really should be, which is, ultimately, practical and efficient.

The Enyaq has a better COD than its outdated predecessors. It has much better practicality. Its space footprint is more efficient due to its height and it is far, far easier to enter and exit with its higher roof line. It doesn't need a huge powerplant to move it as electric motors have a substantially better torque and power range than any ICE.

The design basis for cars has utterly changed. The old rules are in the bin.

New EV cars should look nothing like old ICE cars. It is a bugbear of mine atm that some manufacturers are still stuck in the past ICE mould.

If you want to see the future for EV car design, look at the Citroen Ami for clues. Highly practical and a design not handicapped by speed considerations alone.

SUV is a bad name. There is nothing "Sports" about these cars. They are just General/multi purpose vehicles designed as such.

As i get older, my days of contortionist flexation to get into the previous generation of "Cars" is over. Give me a "SUV" access profile anyday.
Don't forget frontal area. The drag force is proportiona to Cd x A. I'll bet that the frontal area of a Passat is less than an Enyaq.

I entirely agree with you about the design of EVs needing to be freed-up from historic convention. However, I believe that high speed performance (legal UK motorway speeds) is important if you are trying to design a generally useful car and not just a niche city runabout.

I too have to consider the getting in and out issue. For me the slightly more upright hatchback shape of the ID3 is a perfect hight. SUVs are too high!. I suppose it dependes on the length of your legs.
 

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Discussion Starter · #14 ·
Don't forget frontal area. The drag force is proportiona to Cd x A. I'll bet that the frontal area of a Passat is less than an Enyaq.

I entirely agree with you about the design of EVs needing to be freed-up from historic convention. However, I believe that high speed performance (legal UK motorway speeds) is important if you are trying to design a generally useful car and not just a niche city runabout.

I too have to consider the getting in and out issue. For me the slightly more upright hatchback shape of the ID3 is a perfect hight. SUVs are too high!. I suppose it dependes on the length of your legs.
Good points, its the speed (^2) that kills you.

I can't find data for the frontal area of the MEB platform cars.

But, they are not intended for high speed driving. You want the Porsche Taycan for that :)

Is 70mph really "high speed"?
I don't think it is. It's certainly going to hurt your ev range though.
Oddly enough, the MEB SUVs rate higher for efficiency on the EV database than some of the more traditional lower slung cars. I believe the efficiency values are rated at TEH? (References on the EV database are poor, ).
 

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Good points, its the speed (^2) that kills you.

I can't find data for the frontal area of the MEB platform cars.

But, they are not intended for high speed driving. You want the Porsche Taycan for that :)

Is 70mph really "high speed"?
I don't think it is. It's certainly going to hurt your ev range though.
Oddly enough, the MEB SUVs rate higher for efficiency on the EV database than some of the more traditional lower slung cars. I believe the efficiency values are rated at TEH? (References on the EV database are poor, ).
70 mph is the highest speed that the man-in-the-street needs for his car. Anything more is only for bragging rights down the pub or maybe to scare yourself on the occassional holiday in Germany.
 

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Well, does size really matter?
Is big really not best and is a smaller one used more often a better choice?

Good guidance for choosing battery size for your EV needs are few and far between and are in my experience, rubbish.

There are no rules of thumb i can find either and any attempt to guage battery requirements ignore OEM requirements or usage patterns or degredation.

I am 2 months in with EV ownership. I couldn't afford a 80+kw battery so had to settle for a 60ish kw version instead.

The experience has been enlightening.

Not only do i not need a bigger battery, but the smaller battery is both better for the car and the environment (and my wallet).

I think that a rule of thimb is that your battery should give you twice the range of either your high daily median mileage or your singular long distance trips if they are are your norm.

So, if you do 3000m pa and your car is parked up for most of its life, just get the smallest battery version of the car you are considering. For the odd long trip, get used to the public charging network,

If you do 30000 miles a year by frequently using the car on medium trips, again buy the smallest battery that fits the above rule of thumb. A 60kw battery can easily give you a annual mileage of 30k.

Big batteries are only needed for high power usage between charging. For example:
  • If you are time sensitive and do long distance.
  • You have no private charging capabilities and can only use public chargers.
  • You live in a region which requires high power for heating/cooling.
*Your name is Nigel Mansell.
Good call, and something I often try to reflect on too.
 

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Discussion Starter · #17 ·
70 mph is the highest speed that the man-in-the-street needs for his car. Anything more is only for bragging rights down the pub or maybe to scare yourself on the occassional holiday in Germany.
"I bought the biggest, fastest, most powerful EV because i love the planet"

Doesn't really work, does it?!

The MEB platform is limited to 160kmh which is more than fast enough for me. The sub 10s 0-60 time is also more than enough for me.

What is interesting is that owners now, more than ever, will be more conscious of the performance profile they will be buying into with an EV over Ice as really, even the lower powered EVs are more than capable for legal use.
 

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"I bought the biggest, fastest, most powerful EV because i love the planet"

Doesn't really work, does it?!

The MEB platform is limited to 160kmh which is more than fast enough for me. The sub 10s 0-60 time is also more than enough for me.

What is interesting is that owners now, more than ever, will be more conscious of the performance profile they will be buying into with an EV over Ice as really, even the lower powered EVs are more than capable for legal use.
If "more than capable for legal use" is the scope of the relevant metrics, and the world really is in danger, let's bring national speed limits down to 65mph and put speed limiters on all new cars.

Let's go! Do it!
 

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The C.O.D. of the Passat estate is 0.3
The C.O.D. of the Enyaq is 0.28.
This
Don't forget frontal area. The drag force is proportiona to Cd x A. I'll bet that the frontal area of a Passat is less than an Enyaq.
and the fact that the Passat was designed to cool a 5.0 litre V10. Internal airflow is really inefficient.
Call them what you like, cars with big frontal areas are bad for the environment. Whilst it may not be the case for you, a lot of people are buying Crossover SUVs for a misguided sense of power. If you need a tall car then a tall but narrow car like an i3 is a better answer than a brick like SUV. They are also encouraging the proliferation of stupid size batteries so that people don't have to compromise their range and performance in comparison to ICE. :devilish: Wrong, we need to consume less.

If "more than capable for legal use" is the scope of the relevant metrics, and the world really is in danger, let's bring national speed limits down to 65mph and put speed limiters on all new cars.

Let's go! Do it!
Yes Brother!

Of course I'm entitled not to as some scrote somewhere will bypass the restrictions and gain an advantage, and if she's doing it well why not me? :cool::devilish::rolleyes:
 

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Discussion Starter · #20 ·
This

and the fact that the Passat was designed to cool a 5.0 litre V10. Internal airflow is really inefficient.
Call them what you like, cars with big frontal areas are bad for the environment. Whilst it may not be the case for you, a lot of people are buying Crossover SUVs for a misguided sense of power. If you need a tall car then a tall but narrow car like an i3 is a better answer than a brick like SUV. They are also encouraging the proliferation of stupid size batteries so that people don't have to compromise their range and performance in comparison to ICE. :devilish: Wrong, we need to consume less.


Yes Brother!

Of course I'm entitled not to as some scrote somewhere will bypass the restrictions and gain an advantage, and if she's doing it well why not me? :cool::devilish::rolleyes:
I should add that i don't really consider the MEB platform to be SUV hence my points.
If you are talking about full 4wd Chelsea tractors then i would agree with you.
 
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