Charging Curves

[Smitty79]

I've watched many watched many videos that show how fast different electric cars charge. The key seems to be how fast the the charging rate drops off, rather than peak rate, as long as the peak rate is over 150kW.

The current Teslas, seem to be much better than the new, likely high volume, competitors (ID4 and Mach E). But I don't see people talking about this when they are comparing the cars.

Does anyone have a good link to charging curves for current and either high volume or likely to be high volume EVs? I'm looking for charge rate vs state of charge or time to charge to a given SOC.

 

[GtiMart]

I haven't seen manufacturers publish this. In the case of Tesla for example, I believe the curve has changed over time so you need to be careful what data you get your hands on. These curves are theoretical maximums but there are other factors that affect the effective speed, like battery temperature. Another is effective charger output, affected by power sharing.

I understand why Tesla and other manufacturers are choosing to hide a lot of the data. Too much information, optimization strategies etc can (and will) discourage most people to move to an EV. Keeping it simple, "it always works", makes it more palatable. Techies and geeks like me (and you?) will want all the data. I still think there's a way to show more information in the UI when charging, without blurting out graphs and numbers, but that's another debate.

You also need to remember that this really only affects people that do road trips. As such, fast DC charging speed might be low on the priority list for a significant amount of people. I have used superchargers like a handful of times in 18 months of ownership...

You could say this is somewhat similar to horsepower numbers for ICE cars... manufacturers will give you the peak, they won't say much about what happens all over the power band. You need to research for dyno graphs. On EVs manufacturers tend to say two things: max kW for charging, and sometimes "x minutes to go from 20% to 80%" for example. Really, if you get that second value, you cover a lot of ground. This may be a lot more palatable for the masses than a charging curve. Mind you, I personally want the graph but I recognize I'm in a minority.

 

[mark95476]

TeslaBjorn has a bunch of videos where he compares charging rates, curves, best practices, ...etc...

 

[Candleflame]

Also these curves all have to be voltage standardized. Theres a lot of marketing going on.

I.e. tesla has a 4.5% bottom buffer but charges to true 100%.

Audi i think has a 2% buffer but they chose to set 100% to 90%.

What sounds better?

Audi etron 320km real world range with 0 to 80% charge in 18min or audi etron with 350km real world range with 0 to 80% charge in 30min.

Especially looking the topend and extending the bottomend makes a huge difference to charge time.

There needs to be regulations for this but this is all new stuff for all of us. I reckon voltage should be standardized and hence recharge time should be advertised as 20% to 80% true soc.... (So for a model 3 that would be displayed 16% to 79% or smth....)