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I thought I would 'test' rapid charging using a nearby Instavolt. I am sure before starting it 'informed' that it was a 75kW charger, yet during charge it maxed at 39kW. Is the first rapid charge constrained? Am I missing something? At least it worked!
 

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Instavolt chargers are nominally 50kW maximum. You are unlikely to see even 50kW in a typical EV because by the time the pack voltage gets high enough to hit 50kW, the car is throttling the charge current.

I don't know enough about the Niro to be sure about throttling.
 

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A typical 50kW CCS charger is 125Amps maximum, 500Volts maximum and 50kW maximum.


Power in Watts = Amps * Volts.

50kW = 125A * x Volts. Solve for x.


x = 50kW / 125A = 400Volts.

Your car's battery needs to get to 400Volts without tapering the charge current to see a 50kW peak charge. I don't know if the Niro can do that.
 

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I thought I would 'test' rapid charging using a nearby Instavolt. I am sure before starting it 'informed' that it was a 75kW charger, yet during charge it maxed at 39kW. Is the first rapid charge constrained? Am I missing something? At least it worked!
How low was your battery SOC when you started charging?
It seems with some cars/ chargers that a high rate will occur when the battery SOC is low but this can tail off during the charging process as the SOC climbs...
 

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Fastned have pubished charging curves for the e-Niro. On their 50kW charger, the 64kWh e-Niro car briefly hits 48 or 49kW around 70% charge.

123959



See here:
 

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Discussion Starter #8
OK, so the power might have increased if I had charged to a higher %? I only charged to 20%. I certainly hope it increases.
 

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If I use a rapid charger (generally Podpoints) generally I will start the charge at around 20% and I get a charge rate of something like 42 kW. This slowly increases during the charge to around 48/49kW at around 69/70% and keeps this rate until about 75% when it drops to around 35kW, it then drops to 23kW at around 78%. I have never charged to over 80% on a DC as
1. It ain't good for the battery if charged to 100% regularly
2. It simply takes too long to go to 100% from that point - if you need more it would be a lot quicker to drive to another charger 200 miles further on and charge up to 80% again from there.
 

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If I use a rapid charger (generally Podpoints) generally I will start the charge at around 20% and I get a charge rate of something like 42 kW. This slowly increases during the charge to around 48/49kW at around 69/70% and keeps this rate until about 75% when it drops to around 35kW, it then drops to 23kW at around 78%. I have never charged to over 80% on a DC as
I regularly use a BP chargemaster rapid and get the exact same trend as Devon dumpling, charging 20% - - > 80%
 

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The conclusion is that what you experienced is perfectly normal if starting at 10% soc when you plug into a 50kW rapid charger.
If you want to see a faster speed you'll need to find a 150kW rapid, and charge up to 50-55% soc, iirc, to see 70kW charging.

I did try the Ionity 150kW chargers at Maidstone once as I was passing and did see 70kW+ but mostly rapids are 50kW so 40-45kW is a normal charge rate.
 

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After a drive in excess of 200 miles I plugged into Ionity (Gretna) at 10% SOC, got 45-47kw up to mid 30's SOC then charger ramped up to 70kw, maxed out at 78kw in low 50's SOC, the usual slow down points then ensued as described earlier. DC Rapid Charging will not harm the battery as the BMS slows the charge to completion.
 

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  • It slows the charge because the BMS is operating on cell voltage control, as the charge goes up the cell charging voltage including the voltage due to internal resistance increases. Do you have any battery cell voltage monitoring app?
 

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I have been trying the new 150kW Polar chargers at Colchester BP services. I've turned up with 33%, 41% and 56%, never got over 56kW out of them. I'm beginning to wonder if they're really putting out 150..
 

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I have been trying the new 150kW Polar chargers at Colchester BP services. I've turned up with 33%, 41% and 56%, never got over 56kW out of them. I'm beginning to wonder if they're really putting out 150..
150kW is just a nameplate. Any DC charger output volts and amps. The volts is a function of the cell number and design. Record volts and amps and see if it achieving the vehicle limits
 

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I'm not overly up on the technical side but I did expect to see 70kW or so on an e-Niro at some point in the charging process.
 

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I saw about 75kW on the Niro when charging on the Ionity 150kW rapid at Maidstone a few months back. You should be seeing similar on the Polar chargers if it is rated at 150kW
I'm wondering if they have an issue with the Colchester 150kWs as the guy in the shop said they keep coming back to sort the charging speed.
 
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