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Sorry for all the noob questions! Just wondering why rapid chargers have such a varying degree of speed. I've only had my EV for a week (Kia eNiro) and I have tried a few chargers with varying results. This morning I charged at a Shell Allego charging station which is advertised as 50kw but I was only getting a rate of around 24kw. Is this an issue with the charge point or the vehicle?
 

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The car actually controls the charge rate and it limits it depending on factors like the battery temperature and current charge level.
You need to tell us more about that to get a reasonable answer.
Eg. It's cold out, so if you haven't worked the car hard for a while the battery will be cold.
 

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Hi. There are potentially lots of reasons, both car and charger related.

Car:
Cold battery.
High existing battery state of charge.

Charger:
Restricted hardware.
Restricted power input due to local grid or other rapid chargers sharing the same grid connection.
 

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Thanks. So it was early this morning, outside temp probably 4-6 degrees. Had only done around 5 miles before reaching the charger so I guess the battery would still be cold? Plus I dont think it took on much, if any, charge overnight on the basic 3 pin charger. Could this also be down to the weather?
 

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Cold battery, cold ambient temperature, and little mileage to charger (cold pack, again) would mean that the battery management system would limit the charge rate on a rapid to preserve the battery pack.
 

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The main reason is the chargers are Amp limited, and the battery has a set voltage (which varies depending on SOC).

The stated 50 kW is a theoretical maximum based on 500 volts (or whatever the design spec is). Most packs are well below this.

Add to that charger losses and maybe restrictions on the car wide due to cold/heat or SOC. As already pointed out.
 

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I have only had the MG ZS EV for two weeks and tried three local ChargePlace Scotland chargers.

In all cases the car has been driven for long enough to warm the batteries (its liquid glycol heated/cooled, not air regulated). Two charge at full rapid rate no mater the ambient temperature. The third at about half the rate. When I called the help line then made a note of this as they said there were no load balance limited applied to the charger at the time so should be charging at 50kW. So perhaps faulty.

Interestingly the two 'normal' chargers show three things during charging - time connected, kW delivered and the car's battery %. The third slower charger showed 20.83 kW delivered as soon as the car was plugged in. 45 minutes later it still showed 20.83 kW so may indeed have been faulty, or did not reset correctly after the last user. This third charger charged the car from 19% to 59%.

My local 'normal' charger charged the car recently from 59% to 90% in 47 minutes.
 

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Welcome to winter in an EV. Even under optimum conditions you aren't likely to get 40kW never mind 50kW.

Even long A-Road / Motorway driving may not be sufficient to get the pack to temperature. Other factors to consider are - are you sitting in the car with the cabin heater on? That will drain a significant proportion of the power that could be going to the battery.

I use a rapid on a Friday on my way home from work in my Model 3. Try to arrive with around 20% SOC and get around 38kW on a 50kW rapid. It will ramp up a little to 42kW before dropping back down as the pack reaches a higher state of charge.

Perhaps some other ZS owners can report back how their car behaves because we don't know how MG have set their BMS, they have it set relatively conservatively to avoid degradation.
 

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I use a rapid on a Friday on my way home from work in my Model 3. Try to arrive with around 20% SOC and get around 38kW on a 50kW rapid. It will ramp up a little to 42kW before dropping back down as the pack reaches a higher state of charge.
On these types of chargers you might get a faster charge at a higher SOC due to the fact the pack voltage will be higher.

Certainly on the Model S/X the Chademo can be faster than a Supercharger above 80% SOC or so.
 

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On these types of chargers you might get a faster charge at a higher SOC due to the fact the pack voltage will be higher.

Certainly on the Model S/X the Chademo can be faster than a Supercharger above 80% SOC or so.
Not seen it beat a supercharger yet - will see what Summer brings. Try to only charge to 80% anyway and be on my way again so someone else can jump on the rapid.
 

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Thanks. So it was early this morning, outside temp probably 4-6 degrees. Had only done around 5 miles before reaching the charger so I guess the battery would still be cold? Plus I dont think it took on much, if any, charge overnight on the basic 3 pin charger. Could this also be down to the weather?
What was the battery charge % when you plugged in?

The 3-pin charger (usually called the granny charger here) only delivers about 2.2kW, so the temp and SoC are unlikely to affect its rate. But allowing for losses it will only add about 20% (~50 miles) to a 64kWh pack in 8 hours.
 

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What was the battery charge % when you plugged in?

The 3-pin charger (usually called the granny charger here) only delivers about 2.2kW, so the temp and SoC are unlikely to affect its rate. But allowing for losses it will only add about 20% (~50 miles) to a 64kWh pack in 8 hours.
OP is talking about rapids.
 

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Thanks. So it was early this morning, outside temp probably 4-6 degrees. Had only done around 5 miles before reaching the charger so I guess the battery would still be cold? Plus I dont think it took on much, if any, charge overnight on the basic 3 pin charger. Could this also be down to the weather?
Cold battery and/or starting from a high SoC are why. Your trickle charger will not warm the battery much, nor will 5 miles.
 
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