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Discussion Starter · #1 ·
Hi,
I note that when I charge at home I get a max range of 230, however if I use CCS (50kW) charger i get on average 270+ (based on last few months).

Has anyone else noticed any patterns?
 

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I assume that is at the same battery percentage? Also was the trip calculator showing the same kwh useage? It seems bizzare but my first thought is simply whether the car is reacting to a different driving pattern immediately before the charge? What power is your home charger?
 

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Discussion Starter · #3 ·
Home charger gives me 6.8kW (forgot to mention that). It’s odd. In London I get higher range on a full charge than I do in the midlands. No change in anything (ie driving style)
 

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so you charge at home in the midlands ( I also get 6.7kw from my home charger) and 50kw in london? Is the difference a one off or every time? I still think it is likely a diff in the efficiency achieved in the trips before the charge. so if locally you are mainly doing town stop start driving and then do a london trip with a better efficiency and then charge the suggested km from the state of charge will be affected.

So lets say in the midlands you av 22.5 kwh/100km a 100% charge would show a range of 355km (80 div 22.5 = 3.55 x100 = 355). If before the london charge the trip meter shows say 20.5kwh/100km then 100% would be 390km. Sorry for using km but it is how my car is set up but it shows the thinking….temperatures also affect efficiency so say a journey in the early morning where it is say 10deg C v the same journey in the afternoon at 25deg c may give a different efficiency but generally I think it is the much colder temps that causes losses though high do as well. But the midlands is not that far from london🤣

I went on a 32km trip today and achieved 19.2kwh/100km. The return was 22.9kwh the difference being it is more uphill coming back. The av between the 2 is 21.2kwh/100km. The car has 32% SOC and a stated range of 121km. Theoretically 100% charge is 80kw so each kw is .8. At 32% SOC the battery has 25.6 kwh (.8x32). 25.6 div by 21.2 (kw divided by the last average trip efficiency reading) = 1.2075 so rounded up 121km range. If I go back on my outward journey at 19.2kwh the range would be 133km.

To achieve the advertised range of 414km given under the WLTP regs I need to achieve a kwh/100km figure of 19.32kwh/100km ( 80kw divided by 414 x 100) and I have seen figures near that and lower so the car does have the ability if the driving conditions (traffic, terrain, and weather) allow.

I strongly suspect thinking this through it is all done to the consumption at the start of the charge that is altering the range not how quickly the power goes in, the car is either charged or not and 80kw battery cannot have 90kw squashed into it as far as I am aware🤔 would be very pleased to get others views on my thinking.
 

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I read somewhere that MB calculate your range based on your average consumption over the last 200 miles, for both EVs and ICE vehicles.
 

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I read somewhere that MB calculate your range based on your average consumption over the last 200 miles, for both EVs and ICE vehicles.
Just checked my car after a short trip today when I had hoped to charge the car at a public charger (Lidl which is free) only to find the borne was not working😱it connected but would not start a charge. One side was out of order and the door would not open the other you could open it and plug in but no charge…..great experience why I am pleased to have a home wallbox! Anyway the battery is now at 20% SOC so 16kw and is showing 74km range. At todays trip figure of 20.5kwh/100km it works out at 15.17kw needed to cover 74km. Using the overall since last reset figure (over 717 km) of 21,6kwh/@100km it needs 15.98kw so the car is certanly using trip data but which one is perhaps still not entirely clear but if I look at the last journeys over 210km the average is 22.79kwh/100km which gives a figure for 74 km in 16.8kw I shall keep on crunching the numbers to see if I can find an answer😉
 

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It's not easy to keep a rolling consumption average like the onboard computer does, but looking back over my data I can believe it's using the last ~300km in its average.

If you want to get into a detailed analysis, keep in mind there's a bit of quantization error in the SoC percentage; you only get 2 significant digits there, but 3 in range and consumption. That's most evident if you compare SoC/Range at the beginning and end of a charge. Presumably the computer is using the same consumption figure before and after the charge because the vehicle hasn't been anywhere, but you'll find a discrepancy. If you're really keen, you can even use that discrepancy to tease out a bit more resolution in the SoC percentage:

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