Ours have 3 settings, which is great as you don't get roasted, they just keep you slightly toasty.
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- Thread starter Ricochet J
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Ours have 3 settings, which is great as you don't get roasted, they just keep you slightly toasty.
Agreed as it’s also the only way to take into account the charging losses. Although this could change depending on how you charged it.
I skipped to the end and they all managed roughly 80% of their WLTP range which is in the ball park of what you’d expect in a relatively mild day in autumn, although the M1 speed limit is probably flattering this somewhat and it’s likely to be lower on a faster road.
It would drop to 70% on a cold winters day on another motorway what don’t have a 50mph limit for half its length and rise up to 85%ish for a typical summers day.
It’s the WLTP test setting unrealistic expectations rather that cars ‘only getting 80% of their quoted range’ as a few of their drivers said. 80% of WLTP is pretty good going in reality.
Soldato
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for
CLA today is a transverse engine install anyway!
It’s to balance launch acceleration with top speed without overspeeding the motor so it burst.
So asking the audience questions like you have the answers when it’s only ever your knowledge that’s lacking.
CLA today is a transverse engine install anyway!
It’s to balance launch acceleration with top speed without overspeeding the motor so it burst.
So asking the audience questions like you have the answers when it’s only ever your knowledge that’s lacking.
Soldato
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Question for EV drivers.
I used a public charge point for the first time yesterday as I need a bit of juice to complete a long trip.
According to the fast charger I added 10 kWh. My battery is 61 kWh so that is 16%.
According to the car I went from 23% to 36%, so that's only 13%.
But when I started driving again I lost 4% really really fast, like within a couple of miles.
Ergo the 10 kWh of charge I added got me only half the added range I expected.
Is fast charging less effective somehow than standard charging?
I used a public charge point for the first time yesterday as I need a bit of juice to complete a long trip.
According to the fast charger I added 10 kWh. My battery is 61 kWh so that is 16%.
According to the car I went from 23% to 36%, so that's only 13%.
But when I started driving again I lost 4% really really fast, like within a couple of miles.
Ergo the 10 kWh of charge I added got me only half the added range I expected.
Is fast charging less effective somehow than standard charging?
I agree, as you don't buy a car using quoted motorway range, WLTP isn't great but there no exact way to tell each and every person what to expect based on their own personal day to day use. I guess they need to start just using the EV database style, city/combined/highway figures to help people work out what range they should expect, along with the set for environmental differences.
to be more specific I thought the newer bearing tech meant motors could run faster which puts them in a more efficient range ...
so the low gear is for low speed take-off ... since motor burst possibility is now a lower risk ... so I thought it was opposite of what you said.
You pay for the total delivered to the car, and the losses due to heat etc.
The important bit of missing info is what % did you end up on and how many miles did you cover after the charge?
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3% difference between charger and car would be nearly 2 kWh out of 10 delivered, that's only 80% charging efficiency is that right? Seems really poor if so.
Re the miles, can't judge that as when I got home I was on 5% battery remaining but the miles range display had gone blank (it must do that on this model if it can't estimate how far is left?)
How does 3% = 20%?
He's referring to the difference in reported charge between charger and car - charger said 10kWh which should be 16% added, car only reported 13% added which would be nearer 8kWh
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Yes as Kenai says.
Full story if it helps.
I left house at 100% which was 196 miles according to the car.
I arrived at destination 96 miles away with 52% and 104 miles remaining. So I thought I'd done pretty well. 48% of 61 kWh for 96 miles is about 3.3 miles per kWh.
On the journey back it was windy so it soon became apparent I was short by about 10 miles on my range. I was only getting about 3.1 miles per kWh.
At about 40 miles range remaining, 23%, I stopped for charge. I still had 46 miles to go so 6 miles short.
I charged 10 kWh in about 20 minutes, charger reporting around 50 kW charge rate.
Battery is 61 kWh so 10 kWh should equal 16%.
Car only went from 23% to 36% which is 13%.
So yeah that means I'm short by 3% of 61 kWh or around 1.8 kWh. Making charger only 82% efficient.
But 8 kWh added charge at 3.1 miles per kWh should get me an extra 24 or so miles.
My range only increased by 19 miles when I first started driving, and then fell sharply very quickly so I only had a range about 10 miles more than before.
I finished trip on 5% but the range display had switch to '--' presumably it does this when the battery gets very low?
So I ended up doing my 192 mile trip from 61 kWh full battery plus 8 kWh mid trip charge and remaining on 5% which is 3 kWh so that is 61 + 8 - 3 = 66 kWh. For 192 miles that is 2.9 kWh per mile which is less than reported by the car.
Full story if it helps.
I left house at 100% which was 196 miles according to the car.
I arrived at destination 96 miles away with 52% and 104 miles remaining. So I thought I'd done pretty well. 48% of 61 kWh for 96 miles is about 3.3 miles per kWh.
On the journey back it was windy so it soon became apparent I was short by about 10 miles on my range. I was only getting about 3.1 miles per kWh.
At about 40 miles range remaining, 23%, I stopped for charge. I still had 46 miles to go so 6 miles short.
I charged 10 kWh in about 20 minutes, charger reporting around 50 kW charge rate.
Battery is 61 kWh so 10 kWh should equal 16%.
Car only went from 23% to 36% which is 13%.
So yeah that means I'm short by 3% of 61 kWh or around 1.8 kWh. Making charger only 82% efficient.
But 8 kWh added charge at 3.1 miles per kWh should get me an extra 24 or so miles.
My range only increased by 19 miles when I first started driving, and then fell sharply very quickly so I only had a range about 10 miles more than before.
I finished trip on 5% but the range display had switch to '--' presumably it does this when the battery gets very low?
So I ended up doing my 192 mile trip from 61 kWh full battery plus 8 kWh mid trip charge and remaining on 5% which is 3 kWh so that is 61 + 8 - 3 = 66 kWh. For 192 miles that is 2.9 kWh per mile which is less than reported by the car.
you will find out whether 5% remaining was honest when you do a home recharge (of the lfp) to 100%
I thought LFP charge level was inherently not so accurate so the car is pessimistic/sand-bagging on charge remaining to make sure you get home, and also on the increased range from the 10Kwh refill, for which
82% efficiency seems low .. should be 90s.
(aren't cars reading the cell voltages as an indication of charge%, but LFP's have some parasitic losses that are hard to model, when you recharge to 100%, model is refined for subsequent trips)
I thought LFP charge level was inherently not so accurate so the car is pessimistic/sand-bagging on charge remaining to make sure you get home, and also on the increased range from the 10Kwh refill, for which
82% efficiency seems low .. should be 90s.
(aren't cars reading the cell voltages as an indication of charge%, but LFP's have some parasitic losses that are hard to model, when you recharge to 100%, model is refined for subsequent trips)
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Parasitic losses? Huh?
LFP just has a very flat voltage /SoC curve until nearly full. Measuring voltage is a guess, much like your postings in this thread. Word soup full of guesses.
Model is refined? No the BMS knows the cells were full so can use the current counters for a few more hours of use with confidence they are accurate.
LFP just has a very flat voltage /SoC curve until nearly full. Measuring voltage is a guess, much like your postings in this thread. Word soup full of guesses.
Model is refined? No the BMS knows the cells were full so can use the current counters for a few more hours of use with confidence they are accurate.
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Part of the equation is the charger is billing you for the AC input, not the DC that end up in your battery.
There are losses in the charger and car which you’ll have to pay for.
Also are you sure the cars usable capacity is 61kwh? You’ve got an MG5 right, quick google suggests the gross capacity is 61.1kwh but the bit you can actually use is only 57.4kwh.
[
battery losses where you don't get out the electrons you put in is obviously what lfp are renown for, so need to recharge to tally up
all battery packs in same cars are different and a learning model refined for performance on future discharge cycles, logical,
it's even driver specific, if your style is periodic heavy acceleration/discharge calls, say.
what's you explanation then for the inconsistent data dan has ?
if the % were with respect to net capacity you'd expect mftr/mg wouldn't obfuscate the figures.
]
ok that's an electronic engineering term I'm familiar with - ask your mates - but an analogous term for losses in lfp batteries is logical
battery losses where you don't get out the electrons you put in is obviously what lfp are renown for, so need to recharge to tally up
all battery packs in same cars are different and a learning model refined for performance on future discharge cycles, logical,
it's even driver specific, if your style is periodic heavy acceleration/discharge calls, say.
what's you explanation then for the inconsistent data dan has ?
if the % were with respect to net capacity you'd expect mftr/mg wouldn't obfuscate the figures.
]
Soldato
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I didn't expect 80% efficiency though. High 90s I'd have expected from a simple AC to DC conversion and charging a battery. 20% losses is massive.
You're correct the gross battery is 61 kWh and the usable is lower. Is the car percentage charge based on gross or usable? If usable then a 13% gain on 57 kWh is even lower, only 7.5 kWh of the 10 kWh I input making 75% charging efficiency.
It *should* be based on the useable capacity but I'm pretty sure MG and some other Chinese manufactures do funny things with their readouts like the % charge not actually being linear.
Likewise I wouldn't take any stock of the gasometers data, it's at best a guess based on your past driving, it has no idea how much power you are about to use going forward. For example, if the last 10 miles of your drive pre-charge were slightly downhill, and the first 5 miles of charge post charge were slightly up hill, get through your 'remaining miles' far faster than the car would have estimated.
As for charging efficiency and where its going, I doubt you'll really know from just looking at the readouts on the screen, you'll need far better datalogging equipment.
Likewise I wouldn't take any stock of the gasometers data, it's at best a guess based on your past driving, it has no idea how much power you are about to use going forward. For example, if the last 10 miles of your drive pre-charge were slightly downhill, and the first 5 miles of charge post charge were slightly up hill, get through your 'remaining miles' far faster than the car would have estimated.
As for charging efficiency and where its going, I doubt you'll really know from just looking at the readouts on the screen, you'll need far better datalogging equipment.
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Got a few issues with the ID7, including windscreen wipers juddering like crazy and not clearing the screen, HUD stopped working and a seatbelt twisted from factory
Contacted 2 VW dealerships to get this sorted and they charge for a loan car.
Pretty shocked about this on a brand new car with issues.
Contacted 2 VW dealerships to get this sorted and they charge for a loan car.
Pretty shocked about this on a brand new car with issues.
They charge for the loan car? Oof
Although thinking about it, the times I've had when I wanted a loan car from other dealerships they've often meant something like a month extra wait compared to booking it in without a loaner so it might be a good rationing system to make sure people really need one