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More aggressive (sooner) supercharge taper on latest firmware?

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First time supercharging on the latest firmware, and I saw a pretty steep taper kick in much sooner than on previous versions. Used to hold 115 kW to 30%, this time it began dropping shortly after I connected at 20%. Good news is that the handle did not overheat, and there was no abrupt decline to 60 kW as experienced by many (including myself). Taper seemed consistent with prior experiences after 40%. Are other 85s experiencing this as well on the latest firmware?

FW: 17.34.xxx
Max battery temp: 42 C

Both front louvers actuated, and the condenser fans began running at a low speed about 10 minutes after I began charging. I conclude, therefore, that the battery was not thermal limited.

Data attached below. Black points are from previous firmware collected anywhere between 2 years ago and 3 months ago. Red data points are from the most recent session where I experienced the early taper.

taper.png
 
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My last software update was in early August, I think--might have been in July. Two weeks ago I charged at Petaluma and Eureka. On both occasions the ambient temperature was at or below seventy degrees. Here are my results:

Eureka: Initial battery level was 23%---116kW
26%---113kW
53%---- 70kW
56%---- 66kW
82%---- 38kW

Petaluma: Initial battery level was 11%---118kW
30%---100kW
50%--- 73kW
65%--- 56kW

Sorry but I do not know how to make nifty graphs and such. I just recorded my information with a pencil and paper.
 
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Last time I charged from 7% to 75%, it held at 115KW until around 35%, and then started tapering down to hit 45% at about 85KW. From there, it was basically tapering 2KW for every 1% until 60% where it would level out around 50KW for the rest of the charge to 75%.

This is a 2014 P85 running firmware 2017.34 2448cfc. Worth noting is that i haven't supercharged ONCE below 90F ambient temperature since I got the car, and usually within 10 minutes both fans are at full speed, compressor is at 100%, and if it's over 95F, AC in the cabin is almost non-existent until above 35% SOC.
 
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Is it just me... or has the initial draw from the SC dropped as well?

I seem to recall (but have not dutifully logged data) that pulling up to a SC with anything less than about 20% SOC would kick into the high one hundred teens and maybe 120.. .and I swear at very low SOC I even saw 130-ish initial draw.

Now it seems not to want to start at much over mid-90's regardless of how low the initial SOC is.

I have not used that much SC in the life of the car...

Any other old 85's noticing this on the latest sofware? (Or is it just my car ... for some reason??)
 
Hmm. You should be getting 110+ from the low SOC start. I've never seen anything over 118 kw even when the pack was brand new. In theory, you can push over 120 kw if you have the cabin HVAC drawing lots of current but I've never taken the oppotunity to try it. Overall, I'm disappointed that Tesla hasn't done anything to improve the taper with the 85 kWh variants (and in fact they may have weakened it or at least restricted the situations where it will perform at max potential).
 
Hmm. You should be getting 110+ from the low SOC start. I've never seen anything over 118 kw even when the pack was brand new. In theory, you can push over 120 kw if you have the cabin HVAC drawing lots of current but I've never taken the oppotunity to try it. Overall, I'm disappointed that Tesla hasn't done anything to improve the taper with the 85 kWh variants (and in fact they may have weakened it or at least restricted the situations where it will perform at max potential).

I know, right?

I will drive the car down to sub-10% SOC and be real observant on next SC cycle.
 
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I own a late 2015 vintage p90d. I've never seen over 113kw. I consider 110+ kw a good charge rate at low soc, say when start charging from about 60 or 70 miles range. Earlier in the spring, I've always had a good taper rate, including charging at over 100 degrees in needles and Yuma.

During the last month, I seem to have had a somewhat more aggressive taper. It was particularly bad last week in gilroy, where it tapered rapidly down to 60 kw or so. Switching chargers didn't help (I was sole vehicle on paired charger). Temperatures were in 60s or 70s, and I started charging when I had about 60 miles range.

Not as scientific as some other folks here, but thought I'd throw in my 2 cents.
 
Have a few new data points for this... arrived at 33% SOC.

At 75kw and 52% SOC right now, and doesn’t seem to be tapering any further. I’ll update if it slows down considerably before 60%.
 

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Last time I charged from 7% to 75%, it held at 115KW until around 35%, and then started tapering down to hit 45% at about 85KW. From there, it was basically tapering 2KW for every 1% until 60% where it would level out around 50KW for the rest of the charge to 75%.

This is a 2014 P85 running firmware 2017.34 2448cfc. Worth noting is that i haven't supercharged ONCE below 90F ambient temperature since I got the car, and usually within 10 minutes both fans are at full speed, compressor is at 100%, and if it's over 95F, AC in the cabin is almost non-existent until above 35% SOC.

That's how my car was when it was new. Mine is also a 2014 85. What is your total mileage on your car?
 
My 2013 S85 with 152.000km on clock now starts tapering at 20-22%. Used to hold it`s own to 28-30% Cant for a fact say when this happend. I dont supercharge that often.

On a 2000km roadtrip I had in august I didnt spend more time than I actually needed to hit the next charger with as low SOC as I dared without compromising my excessive speeding. I charged on average all sessions combined 400km/h. So I suppose not half bad still.
 
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I have a feeling that the aggressive taper is sometimes tied to resistance in the connection between the SC and the car, and of course many of the other parameters that have been mentioned too. Long ago I don't remember seeing the SC power do a partial ramp up ~20kW or so and then drop to 0 before actually kicking in to a full SC charge rate. I was wondering if that is some sort of resistance or load test? or did the SC's always do that? Pretty sure I never recorded that data in the past while I had a data logger connected for charging. I'll try and hook it back up sometime soon when I get to a lower SOC and can do a SC charge
 
That's how my car was when it was new. Mine is also a 2014 85. What is your total mileage on your car?

When I made that post, about 52,000 Miles. I'm at 55,000 miles now (I drive, a lot!) and see it holding 116KW from 7% to about 25%, and then it starts to taper down about 2KW per minute until it finishes charging. This works out to about 108KW at 30% and 45KW at 80% with an almost perfectly smooth curve between the two points.

I have a feeling that the aggressive taper is sometimes tied to resistance in the connection between the SC and the car, and of course many of the other parameters that have been mentioned too. Long ago I don't remember seeing the SC power do a partial ramp up ~20kW or so and then drop to 0 before actually kicking in to a full SC charge rate. I was wondering if that is some sort of resistance or load test? or did the SC's always do that? Pretty sure I never recorded that data in the past while I had a data logger connected for charging. I'll try and hook it back up sometime soon when I get to a lower SOC and can do a SC charge

Hot handles tend to start at 100KW and then quickly fall to 75KW, and then there's another "notch" at 60KW that it'll fall down to if the handle doesn't cool off fast enough. I heard from a birdie that there was a bad revision of the handles that was supposed to fix one issue (water leaking in around the gasket on the aluminum handle with the separate button) and created the hot handle issue... These are now all being replaced, as the techs service them. An extremely dirty charge port on the car can create the same issue, though.

I don't remember seeing the ramp up on the P100DL i test drove in March, but I see it every time now. I also see the same behavior when charging at home... a ramp up to 12amps, a pause, a fall, and then it'll roll up to 40 and sit there.