problem with battery percentage estimation display on 2021

[Waynebo20]

I just took about a 200 mile trip and used 71.2 kW of my 88 kW battery. I left at around 92 % and returned home with a 20% charge. I was doing the calculations and I think the display has a 10% discrepancy. The problem is that I wonder if the lower range and battery % is reliable. Was my car actually at 20% or could it have been much lower. This is very concerning because I would hate to get stranded running out of power from erroneous displays.
I have charged to 100% about once a month to calibrate the display as suggested for the type of battery in the car.

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[Billyk24]

Get an orb2 reader and car scanner pro app to read more information and answer your question

 

[RickMachE]

I just took about a 200 mile trip and used 71.2 kW of my 88 kW battery. I left at around 92 % and returned home with a 20% charge. I was doing the calculations and I think the display has a 10% discrepancy. The problem is that I wonder if the lower range and battery % is reliable. Was my car actually at 20% or could it have been much lower. This is very concerning because I would hate to get stranded running out of power from erroneous displays.
I have charged to 100% about once a month to calibrate the display as suggested for the type of battery in the car.

Your issue is 100% a math one.

92 - 20% = 72%. .72 x 88 = 63.36kWh. You think you used 71.2. Why?

 

[Mach-Lee]

I just took about a 200 mile trip and used 71.2 kW of my 88 kW battery. I left at around 92 % and returned home with a 20% charge. I was doing the calculations and I think the display has a 10% discrepancy. The problem is that I wonder if the lower range and battery % is reliable. Was my car actually at 20% or could it have been much lower. This is very concerning because I would hate to get stranded running out of power from erroneous displays.
I have charged to 100% about once a month to calibrate the display as suggested for the type of battery in the car.

Where did you get the 71.2 kWh figure? If it's from an EVSE, did you account for charger losses (charging is only about 90% efficient, so it takes more power from the wall than the battery will accept)?

 

[Teslaeata]

Haha

The GOM, harshly called so but is for a reason, displays a real time estimate of range valid only at any time of viewing remaining range that is calculated using all sorts of constantly changing variables so its starting point cannot be taken as an accurate prediction of range for a journey because things change during a run which is my experience of over 5 yrs and 127,000miles driving Stangy

 

[New2EV]

100% charge for calibration is only for cars with LFP batteries. Which your 2021 does not have. LFP was not an option until 2023.

 

[OH2AZ2OH]

I find the range estimate at the lower end of the battery range to be more accurate than at the upper end.

 

[rreddy3]

You might want to read through @Mach-Lee ‘s excellent post snd other following comments to learn more about the range and % capacity estimate accuracy. I think you’ll find it interesting and helpful.

https://www.macheforum.com/site/threads/hv-battery-calibration-procedure.23815/

 

[Makiato]

Battery % and range are only tangentially related. Your Range is based on how you HAVE been driving. For instance: putt around at 35-50 MPH for a few nice sunny days, then charge to 100%. 312MILES!!!!!! now go drive on the freeway, up hill into the wind, with a full car in cold weather. call the tow truck at mile 200.

 

[sglewiswl]

A lot of the BS and FUD would be cured by having an advanced screen that shows you actual battery kWh left in the native software. We shouldn't have to do this with Car Scanner and dongle. Drivers have never had to deal with a change in how a car is powered and until charging is ubiquitous most of the FUD will be driven by these differences. I've driven BEVs long enough now that I really don't need to care, but most drivers will need to bridge this gap to feel comfortable.

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