I had to do my first full charge from zero (forced Hv mode) today at work, where our charge system reports data. This is on a 13 month old Prime. As you can see, the depleted battery absorbed 6,333Wh from the grid in 7,670 seconds (2 hours, 7 minutes, 50 seconds). This is on a 208V charger so it would be a bit faster on a 240V charge system.
The Prime charger just does that. My guess is that it's to update the open-circuit battery model by measuring float voltage.
Just had to do another one of these - at 36 degrees F this time, and after 22 months and 24,000 miles of use. New full charge = 5,867Wh That's a loss of 7.4% from the one posted above, which was after 13 months.
Is there some variation based on how much you've used HV mode? For example, if you drive in HV mode for a while it will fluctuate between 1-2 bars of battery on the gauge. You'll have more room to charge if you stop at the minimum of the "1 bar" range just before it starts the engine to charge again. And if it's cold, I think HV mode will start sooner to save more energy to drive the car while the engine warms up.
It's interesting to see the graph but it would take several before and after to draw a real conclusion in my opinion. kind of like saying my car is getting X mpg after 100 miles is not realistic over more time and more tanks.
What was the temperature back in May? I would think that if it was warm then and only 36 this time, that that would make a considerable difference. Another variable would be how deep you were into the HV part of the SOC when you plugged it in.
When I charged in 2018, it was 48F. I was not deep into HV either time but I could have been a tiny bit more in 2018.
Interesting. I rarely fully drain the EV range and then fully charge. I've been consuming about 70-72% of my EV range on the way to work every morning when the temperature is what it is today (just above freezing). Today, after the above-mentioned full charge, I consumed 63%. I don't think this is an improvement in battery performance, just a change in the battery model.
Not knowing what the exact HV level was when starting the charge adds a lot to the margin-of-error. Nonetheless, it provides the basics of what to look for and a means of measuring change. How often do you opportunity recharge (immediate start, rather than hours of cold soak) ?
Most days I do that, but I rarely cold soak since my garage is attached and insulated. When it was 13F out it was 52F in my garage.
Interesting...I just did a full charge, after 29 months and 32,000 miles, and it took 6.3kWh - the same as when new. Maybe the capacity is more temperature or battery management system dependent than I thought.
I should be more clear. I stopped with an estimated charge showing of 6%. The charge took 5,949Wh. 5,949Wh/(100%-6%) = 6,329Wh and it was 6,333Wh after 13 months, as shown in the OP.
Good to know. I just saw Björn’s test of a 2016 Ioniq EV (it’ll be 2017 for us since we use model years) with 96,000km. It may or may not have 10% degradation lol. It was inconclusive but at worse it was 10% and at best, nearly no degradation. Pretty good for 96,000km
