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Last night, myself and Jake @MG ZS EV WEST YORKSHIRE took the Chorley Group Burnley demonstrator on a journey to test the real-world rapid charging capabilities.
I picked up Jake around 7pm from Oakworth, and we headed to the Ionity chargers at Leeds Skelton Lake Services. I used the "Battery Heater" option to ensure that we had warm batteries on arrival. This appears to use around 7kW (20A@360V) at peak, although once the batteries had heated up (after 40 mins), the battery heaters automatically switched off.
On the way there, the "Low Battery Warning, Please Charge" message came up at 24% (46 miles indicated) remaining.
Unfortunately, when we arrived there just after 8pm, there were 4 cars charging (2 Porsche Taycans, and MG5, and a DPD delivery van, with 2 other DPD drivers queuing to use them. Faced with a potential delay of over an hour (the DPD vans needed 90%+ to be able to do their deliveries the next day), we checked on Zap-Map, and found there were some 100kW+ Instavolt Rapid Chargers in Barnsley, 26 miles away.
We had 15% battery.... and it was mainly motorway, but were showing 30 miles range on the GoM, so figured we might as well go for it.
At 14% (24 miles remaining), another "Low State of Charge, Please Charge" warning came up on the dashboard.
At 7%, the GoM went to "---", and power was restricted - we were on the M1 going up a hill past Woolley Edge services, and our speed (with foot flat to the floor) wouldn't exceed 50mph. We started to get a little bit nervous. We decided to come off the M1 at the next junction, and go on the A/B roads to Barnsley, as we didn't want to be a hazard for anyone.
We finally got to the chargers (next to McDonalds) with 3% battery remaining. Thankfully, the chargers were both available and working (not ICEd).
We started the charge, and recorded the Amps & Volts from inside the car, to calculate the charging power. The charge was started at 20:56 (nice round number... should have waited a few minutes I guess!).
Initially, the charge started quite slowly, as the charger and car decided what power was best. At 4%, it was delivering 181A @344V (61kW). By 6%, the current had increased to 200A, where it stayed fairly consistently (did drop to 199A for a bit) until it got to 60% SoC. As the battery voltage rose, so the total kW increased, peaking at 76kW at 59/60% SoC.
From 61-71%, it continued at 179/180A, then from 72% it dropped to 151A, where it remained until 82%. At 83% (21:41 - 45 minutes after we started), it then dropped off quite quickly to 67A, stepping down to 61A by 89%. At 90% it dropped to 52A, and at 91% it was at 40A@403V (16kW). This is where we decided to disconnect the charger (it was 21:56, so exactly one hour from when we started).
For reference, it got to 22% after 10 minutes, 41% after 20 mins, 58% after 30 mins, and 83% after 45 mins. This compares very favourably to MG's own stated charge times of 42 minutes to 80% when using a 100kW rapid charger.
Graphs showing the Volts/Amps, and then the calculated kW Power are below:
In conclusion, the new ZS EV has a great charging curve, where it draws 70kW+ from 7% to 60%, and then maintains 60kW+ up to 80% SoC. The battery heater works well (but bear in mind that the heater will draw up to 7kW, so if you're already low on power, you're going to lose another 20-30 miles of range by using the battery heater). It decimates your efficiency - whilst it was working, I was getting 1.5-2m/kWh rather than 3m/kWh!
The battery heater switches itself off when you turn the car off, so it's not something you can accidentally leave switched on and drain all the battery - you need to actively turn it on for each journey.
I would not recommend running the car down below 10% SoC. The charging speed doesn't benefit, and the reduced power (particularly on a motorway) is not a pleasant experience. It might not be too bad around an urban environment, but hills become an issue when it's limiting you to around 25kW (33bhp!). We struggled up a hill in Barnsley town centre with foot flat to the floor, and scraping to 24mph.
We've got loads of photos etc, but I don't want to make this any more difficult to read than it already is
I've added my excel sheet with the values for Volts/Amps that we saw.
I picked up Jake around 7pm from Oakworth, and we headed to the Ionity chargers at Leeds Skelton Lake Services. I used the "Battery Heater" option to ensure that we had warm batteries on arrival. This appears to use around 7kW (20A@360V) at peak, although once the batteries had heated up (after 40 mins), the battery heaters automatically switched off.
On the way there, the "Low Battery Warning, Please Charge" message came up at 24% (46 miles indicated) remaining.
Unfortunately, when we arrived there just after 8pm, there were 4 cars charging (2 Porsche Taycans, and MG5, and a DPD delivery van, with 2 other DPD drivers queuing to use them. Faced with a potential delay of over an hour (the DPD vans needed 90%+ to be able to do their deliveries the next day), we checked on Zap-Map, and found there were some 100kW+ Instavolt Rapid Chargers in Barnsley, 26 miles away.
We had 15% battery.... and it was mainly motorway, but were showing 30 miles range on the GoM, so figured we might as well go for it.
At 14% (24 miles remaining), another "Low State of Charge, Please Charge" warning came up on the dashboard.
At 7%, the GoM went to "---", and power was restricted - we were on the M1 going up a hill past Woolley Edge services, and our speed (with foot flat to the floor) wouldn't exceed 50mph. We started to get a little bit nervous. We decided to come off the M1 at the next junction, and go on the A/B roads to Barnsley, as we didn't want to be a hazard for anyone.
We finally got to the chargers (next to McDonalds) with 3% battery remaining. Thankfully, the chargers were both available and working (not ICEd).
We started the charge, and recorded the Amps & Volts from inside the car, to calculate the charging power. The charge was started at 20:56 (nice round number... should have waited a few minutes I guess!).
Initially, the charge started quite slowly, as the charger and car decided what power was best. At 4%, it was delivering 181A @344V (61kW). By 6%, the current had increased to 200A, where it stayed fairly consistently (did drop to 199A for a bit) until it got to 60% SoC. As the battery voltage rose, so the total kW increased, peaking at 76kW at 59/60% SoC.
From 61-71%, it continued at 179/180A, then from 72% it dropped to 151A, where it remained until 82%. At 83% (21:41 - 45 minutes after we started), it then dropped off quite quickly to 67A, stepping down to 61A by 89%. At 90% it dropped to 52A, and at 91% it was at 40A@403V (16kW). This is where we decided to disconnect the charger (it was 21:56, so exactly one hour from when we started).
For reference, it got to 22% after 10 minutes, 41% after 20 mins, 58% after 30 mins, and 83% after 45 mins. This compares very favourably to MG's own stated charge times of 42 minutes to 80% when using a 100kW rapid charger.
Graphs showing the Volts/Amps, and then the calculated kW Power are below:
In conclusion, the new ZS EV has a great charging curve, where it draws 70kW+ from 7% to 60%, and then maintains 60kW+ up to 80% SoC. The battery heater works well (but bear in mind that the heater will draw up to 7kW, so if you're already low on power, you're going to lose another 20-30 miles of range by using the battery heater). It decimates your efficiency - whilst it was working, I was getting 1.5-2m/kWh rather than 3m/kWh!
The battery heater switches itself off when you turn the car off, so it's not something you can accidentally leave switched on and drain all the battery - you need to actively turn it on for each journey.
I would not recommend running the car down below 10% SoC. The charging speed doesn't benefit, and the reduced power (particularly on a motorway) is not a pleasant experience. It might not be too bad around an urban environment, but hills become an issue when it's limiting you to around 25kW (33bhp!). We struggled up a hill in Barnsley town centre with foot flat to the floor, and scraping to 24mph.
We've got loads of photos etc, but I don't want to make this any more difficult to read than it already is

I've added my excel sheet with the values for Volts/Amps that we saw.
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