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Has anyone been able to test rapid charge speed through from low SoC to near full?

I tested Ioniq 38kwh this weekend which is advertised at more than 50kW, and it didn't get close.

(My Leaf 40 is faster after 400 miles than the Ioniq on its first charge - so much for rapidgate!)

So very interested in real world experience...
 

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TeslaBjorn tested around 58kW, @Miles Roberts tested at 66kW. James Coates of James & Kate tested at around 56kW. Nobody to my knowledge has tested from a very, very low SoC yet and reported it.
MG claim 43 minutes from 0-80% on a 50kW charger. The European website mentioned 85kW but that has been taken down I have been told!
 

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James Coates suggests at 80% it drops to 24kW then tapers down til finishing at 100% taking 6-7kW.

This suggests an unusable buffer which will protect cell life.

I expect at least a couple of kWh as regen apparently works even at full battery.
 

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I'd be surprised if regen works with a full battery, the charge produced needs to go somewhere.
All EVs have a SOC buffer above 100% displayed - albeit very small in Tesla. Some cars allow the actual SOC to go above 100% displayed for regen. My Zoe does - as can be seen in CANze.
 

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This is a very pertinent question and something that should be considered carefully by a prospective purchaser. In truth it will depend upon a number of factors including specification of charger, battery and ambient temperature. Miles has reported higher, but from what other including Bjorn Nyland and James Coates have posted, the maximum charging speed where supported by charger is as follows:
25% - 58 kW
36% - 54 kW
58% - 40 kW
67% - 37 kW
75% - 36 kW
82% - 17 kW
90% - 7 kW

This suggests that most efficient progress likely by charging when you get down to about 20% up to about 80%.

I though we knew that usable capacity of battery would be 44.5kWh with less than 1kWh as buffer most of which will be at the bottom end, which was a concern from those that would prefer a bit more headroom but couldn't manage it with timers or apps.
 

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This is a very pertinent question and something that should be considered carefully by a prospective purchaser. In truth it will depend upon a number of factors including specification of charger, battery and ambient temperature. Miles has reported higher, but from what other including Bjorn Nyland and James Coates have posted, the maximum charging speed where supported by charger is as follows:
25% - 58 kW
36% - 54 kW
58% - 40 kW
67% - 37 kW
75% - 36 kW
82% - 17 kW
90% - 7 kW

This suggests that most efficient progress likely by charging when you get down to about 20% up to about 80%.

I though we knew that usable capacity of battery would be 44.5kWh with less than 1kWh as buffer most of which will be at the bottom end, which was a concern from those that would prefer a bit more headroom but couldn't manage it with timers or apps.

What it definitely proves is that no one has been brave enough to get down to a genuine low SOC (25% isn't low). 1% SOC I'd consider low, 0% perfect for testing the ultimate charging speed from low SOC. ;)
 

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What it definitely proves is that no one has been brave enough to get down to a genuine low SOC (25% isn't low). 1% SOC I'd consider low, 0% perfect for testing the ultimate charging speed from low SOC. ;)
James did on his long distance range test but didn't record charge speed afterwards. Not really surprising since it was silly o'clock in the morning, he'd just driven 140 miles in one go and was by his own admission 'flapping' at fear of running flat.

The other point that James raised was that the first power bar (of 8) could mean 25% charged, so it takes a brave driver to go much lower.
 

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James did on his long distance range test but didn't record charge speed afterwards. Not really surprising since it was silly o'clock in the morning, he'd just driven 140 miles in one go and was by his own admission 'flapping' at fear of running flat.

The other point that James raised was that the first power bar (of 8) could mean 25% charged, so it takes a brave driver to go much lower.

Takes time for bravery to set in, I guess when there is an app that can show the SOC when below that 25% appears we will have loads of folk racing to a 0% charge. I run my Zoe down to low performance mode often, necessity based.
 

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Regen is heavily throttled on a full charge (you get "regen limited" message on a dashboard). MG has a very small battery buffer, around 2% or so.
We have no ‘official’ figures from MG regarding the buffers top and bottom. It is all pure speculation based on one Chinese report long before the ZS EV came out.
 

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We have no ‘official’ figures from MG regarding the top and bottom of the buffer. It is all pure speculation based on one Chinese report long before the ZS EV came out.
well, this came from a UK presentation and shared on youtube and FB. There is a very good reason it is either true or very very close. Rapid charge degradation is so huge, around 100% indication it is only around 6-7kW. It indirectly confirms there is almost no buffer. RC speed degradation is always a good indication of battery buffer.
 

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As per James's run - 0 miles left on the car equalled 4% SOC on the rapid charger.
Missed that, is that 4% as quoted on the charger screen? Or in car? I'm a bit confused by this the last "graticule" equals 25% of the available charge. So when its gone is it really gone? Does the MG accurately go down to 0 miles, and that means zero, turtle mode? Or is it like in most cars where "---" equals a few miles at normal speed but trying to scare you into plugging in?

well, this came from a UK presentation and shared on youtube and FB. There is a very good reason it is either true or very very close. Rapid charge degradation is so huge, around 100% indication it is only around 6-7kW. It indirectly confirms there is almost no buffer. RC speed degradation is always a good indication of battery buffer.
So what would you prefer? A big buffer to maximise charging speed, but capacity you'll never be able to use. Or minimum safe buffer but allow you more capacity to use time and again.

Thinking of Zoe, the buffer on the 22kwh Zoe is big, so can rapid charge until high SOC (at least before BMS update), but buffer on 41kwh Zoe is much lower?
 

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Missed that, is that 4% as quoted on the charger screen? Or in car? I'm a bit confused by this the last "graticule" equals 25% of the available charge. So when its gone is it really gone? Does the MG accurately go down to 0 miles, and that means zero, turtle mode? Or is it like in most cars where "---" equals a few miles at normal speed but trying to scare you into plugging in?



So what would you prefer? A big buffer to maximise charging speed, but capacity you'll never be able to use. Or minimum safe buffer but allow you more capacity to use time and again.

Thinking of Zoe, the buffer on the 22kwh Zoe is big, so can rapid charge until high SOC (at least before BMS update), but buffer on 41kwh Zoe is much lower?
I'd prefer it to have the ability to limit the charging level... in a car...

PS. TBH it sounds like a bit of trickery from MG side to get the range advantage at the price of more rapid battery degradation and slow charging. Where other manufacturers are trying to put a proper buffer, MG allowing almost all capacity to be used.
 

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I'd prefer it to have the ability to limit the charging level... in a car...

PS. TBH it sounds like a bit of trickery from MG side to get the range advantage at the price of more rapid battery degradation and slow charging. Where other manufacturers are trying to put a proper buffer, MG allowing almost all capacity to be used.
But the buffer is getting less and less on new batteries... everyone is doing it.
 

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According to reports by James Coates there is some regen available at 100% SOC, which implies that there is a bigger buffer at the top than my leaf 40 which has none.
Keyword is "some". We don't know if he charged to 100% or it was just dash indicator showing all bars. With 100% there will be heavily capped regen in pretty much any car. MG is no exception:
124067
 

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Keyword is "some". We don't know if he charged to 100% or it was just dash indicator showing all bars. With 100% there will be heavily capped regen in pretty much any car. MG is no exception:
View attachment 124067
But my Leaf 40 has none. Some is better than none....
 
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