80%Soc Still charging at 90KW

[Mattzz]

Chevron Chargers
Here in Canada chevron chargers has batteries in their chargers and one of the charger’s batteries was out of juice and charging very slow so I switched to another charger. And I have never seen this car charging at 93kw at 80soc that kinda worries me

 

[LoudMusic]

That does seem high ...

 

[kimwin]

And I have never seen this car charging at 93kw at 80soc that kinda worries me

You set charging limit at 90%, the battery is only at 79% so it will continue to charge to 90%.
So why 93kW charging is strange? Is it due to supercharging ? Please educate me, I am still learning about Tesla car.
At home , my 2023 M3SR is charged at 32A , 240V (7.68kW) and the charging rate is linear. Every 10% increase takes about the same number of minutes up to 100%.

I read on the Web that supercharger can charge at 150kW or 250kW rate. Have not used one though.

 

[Rocky_H]

So why 93kW charging is strange? Is it due to supercharging ? Please educate me, I am still learning about Tesla car.

Yes, that is kind of why it is strange. It's in the nature of battery charging, that they can't just blast huge high power charging into them non-stop from empty all the way to full. We refer to it as "tapering", where the power rate has to slow down as the battery gets more and more full. In a very general ballpark, the amount of time going from 0% to 80% was around the same amount of time as that top 80% to 100% when Supercharging. It will start out at 250+ kW, but after a while, that's going to have to come down to 200 and then toward 150, 100, 60, etc. So seeing a high power level of 97kW when the car is nearly to 80% seems a little unusual, except for the very newest cars.

At home , my 2023 M3SR is charged at 32A , 240V (7.68kW) and the charging rate is linear. Every 10% increase takes about the same number of minutes up to 100%.

The tapering effect is still there, but the charging power from your home connection is so low power that it's not anywhere near where that limiting would be. 7kW is hardly anything from the battery's perspective, so it wouldn't have to reduce from that 7kW until it's up around 98 or 99%. It will eventually slow down very near the end though.

 

[RayK]

I read on the Web that supercharger can charge at 150kW or 250kW rate. Have not used one though.

There's also an Urban Supercharger which is limited to 72kW. They are popular around shopping centers as a "full charge" (from near empty to 90%) will take about an hour; plenty of time for shopping or maybe a quick meal. If you used one of the higher power Superchargers, your shopping time would decrease by almost a half. You can identify an Urban Supercharger as they have a monolithic design; about 4' tall with no hole in the middle:

as opposed to the V2/V3

The new V4 Superchargers have the same overall look of the Urban Supercharger but is about 6' tall. If you are familiar with the Bass Pro outlet at 85 and Almaden Expy., those are Urban Superchargers. I believe that there are also some near the southeast corner of Oakridge Mall parking lot. I use the ones near OSH on Meridian and Blossom Hill (Princeton Plaza Mall).

 

[Mattzz]

So I have the half of the first charge logged (don’t know why the second and the other half of the full charge not logged) the first one started at 40kw then went up to 70 very slowly due to cold weather up noth in Canada. Second charge jumped to 90KW and did drop to approx 60 instantly at around 87or so Soc and continued to drop slowly after that. It’s weird cause normally we see a steady curve not something like this. 2023 Shanghai RWD LFP

 

[Mattzz]

Yes, that is kind of why it is strange. It's in the nature of battery charging, that they can't just blast huge high power charging into them non-stop from empty all the way to full. We refer to it as "tapering", where the power rate has to slow down as the battery gets more and more full. In a very general ballpark, the amount of time going from 0% to 80% was around the same amount of time as that top 80% to 100% when Supercharging. It will start out at 250+ kW, but after a while, that's going to have to come down to 200 and then toward 150, 100, 60, etc. So seeing a high power level of 97kW when the car is nearly to 80% seems a little unusual, except for the very newest cars.

The tapering effect is still there, but the charging power from your home connection is so low power that it's not anywhere near where that limiting would be. 7kW is hardly anything from the battery's perspective, so it wouldn't have to reduce from that 7kW until it's up around 98 or 99%. It will eventually slow down very near the end though.

For the newest and cars with bigger batteries from what I recall around 80 Soc the safe limit should be 1c so around 60kw for my car. 90Kw at 80soc should match a performance or 90D&P for older tesla. Possibly software? No way….

 

[KenC]

View attachment 992585
Chevron Chargers
Here in Canada chevron chargers has batteries in their chargers and one of the charger’s batteries was out of juice and charging very slow so I switched to another charger. And I have never seen this car charging at 93kw at 80soc that kinda worries me

Interesting. At 80%, you'd typically see it at around 70kW. A tiny bit of an outlier.

Edit, just noticed you mentioned it's a LFP. I have no idea what LFP charge rates look like.

Okay, I went to Teslalogger.de to look at charge curves, and this is what it shows for LFP. According to their data, on a supercharger, the average is about 61kW, but the variation is quite high, since there are dots up over 100kW.

 

[AlanSubie4Life]

Can do some of your own research on how the display works and exact constant for your vehicle, which is easy to determine. I just don’t know how it works for yours.

Anyway, I think it is something like 60.5kWh degradation threshold for 439km for LFP RWD.

So 60.5kWh/439km = 138Wh/km.

So 635km/hr*138Wh/km = 87.6kW

So probably that 93kW was the energy to the pack and cabin climate control (again, some investigation needed on how these displays are done - easy to do, just haven’t paid any attention for a while). I am fairly sure the display includes pack heating in the value for kW (hence reports of 256kW or whatever), but presumably not in the charge rate (I am less sure of that, though observation would clarify), since that would not make sense.

As usual these numbers are related by the vehicle constant (but have to correct the charging kW, in instances where there is pack heating - presumably).

Still, a high rate regardless. LFPs I think tend to taper a bit less?