Max Power vs State of Charge and Temp

[Old Man Mike]

I'll try to get you some data in the next few days Mike!

That would be great! If you could, please first get the battery up to temp by using Max Pwr ON and ready. Then switch Max Pwr OFF and collect the data for 95, 90, 80 and 75%. A few more points below 75% would be very useful but the top four should be the most interesting.

MarcG: I tried plotting your P85DL Max Pwr OFF data and it appears to be much lower than expected. Had the battery been previously warmed up by having it in Max Pwr ON and ready before switching to Max Pwr OFF? Normally a few launches in Max Pwr OFF will bring the battery up to a good temp but perhaps you need to first get it up to temp with Max Pwr ON.

 

[SDRick]

So once the battery is fully warmed up, does Max Battery add anything?

 

[Old Man Mike]

So once the battery is fully warmed up, does Max Battery add anything?

That's the question I hope to answer with the data. I suspect Max Battery On and Ready enables a much higher current in the v2 Battery compared to Max Battery OFF but fully warmed up. A few early data points suggested this.

 

[Tech_Guy]

took a spirited drive this morning with max power on and then headed to the supercharger, charged up to 97% with max battery power still on. When charged I turned off max battery and floored the car it delivered 480kw at 97% did a few full throttle runs and I got it up to 482kw at 95%SOC but I suspect the battery wasn't truly ready because the power stayed the same at 90%SOC 482kw after quite a few pulls in a short time.

To get better data at 95% Id guess a 100% charge with max battery power on and then some driving on max battery power till its around 95% will be necessary to get some good data at the 95% max battery off given what I saw today... even though it listed max battery as ready right off the supercharger at 97% when max power was off the power was still increaseing or staying the same with each pull from 97% - 90%

 

[MarcG]

MarcG: I tried plotting your P85DL Max Pwr OFF data and it appears to be much lower than expected. Had the battery been previously warmed up by having it in Max Pwr ON and ready before switching to Max Pwr OFF? Normally a few launches in Max Pwr OFF will bring the battery up to a good temp but perhaps you need to first get it up to temp with Max Pwr ON.

No, I had not previously warmed the battery. I personally view the Max Battery Off scenario as "just driving along normally but all of the sudden need to punch it".

So to me, having to warm up the battery first (by either supercharging, doing a few launches, or turning Max Battery Power ON for a while then turning it OFF) does not truly represent real life scenarios.

 

[MarcG]

... even though it listed max battery as ready right off the supercharger at 97% when max power was off the power was still increaseing or staying the same with each pull from 97% - 90%

There you go, proves my point.

 

[Old Man Mike]

Thanks for the data points, Tech Guy. Here is the updated chart:

Note how the dashed yellow line showing performance of the new V2 battery is a nearly constant 480kw from 75 to 95% SOC with Max Bat Pwr OFF. I am now fairly confident that Max Bat Pwr ON does more than just heating the battery. It also sets a higher current limit. As the SOC drops, Max Bat Pwr OFF performance converges to Max Bat Pwr ON and becomes the same around 70% SOC.

The above effect is rather minor but visible for a V1 battery (dashed purple line).

I would love to have the V2 battery performance in my non-refreshed P90DL and would gladly pay at least $5K if an upgrade was possible.

Marc: My suggestion of first turning Max Batt Pwr ON, waiting for Ready and the cutting it OFF was to get data points which prove that Max Batt Pwr is doing more than just heating the battery. It was not suggested as a normal driving scenario.

 

[MarcG]

Marc: My suggestion of first turning Max Batt Pwr ON, waiting for Ready and the cutting it OFF was to get data points which prove that Max Batt Pwr is doing more than just heating the battery. It was not suggested as a normal driving scenario.

I see what you're trying to do, but in my experience Max Battery just warms the battery up. If turn it off after it becomes "ready", the battery is still warm and will perform the same as with Max Battery on until the battery starts to cool. I believe Tech_Guy's post I quote above indicates just that.

 

[Old Man Mike]

... in my experience Max Battery just warms the battery up. If turn it off after it becomes "ready", the battery is still warm and will perform the same as with Max Battery on until the battery starts to cool..

Maybe true for P85DL

Probably not true for P90DL with V1 battery

Absolutely not true for P90DL with V2 battery. Data is clearly showing that no matter how warm the battery is, Max Battery OFF performance will be much lower than Max Battery ON performance.

 

[MarcG]

Absolutely not true for P90DL with V2 battery. Data is clearly showing that no matter how warm the battery is, Max Battery OFF performance will be much lower than Max Battery ON performance.

But that's not Tech_Guy's experience, and he definitely has a "v2" bettery since his car is very new.

Again, I quote what he wrote above:

... even though it listed max battery as ready right off the supercharger at 97% when max power was off the power was still increaseing or staying the same with each pull from 97% - 90%

So in his case, which has a clearly detailed procedure, as well as mine, turning Max Battery OFF did NOT reduce power delivery, which goes against your theory that it does.

By the way, I'm not trying to argue just for the sake of it - I'm just trying to understand the behavior of the car based on observations.

 

[Tech_Guy]

But that's not Tech_Guy's experience, and he definitely has a "v2" bettery since his car is very new.

Again, I quote what he wrote above:



So in his case, which has a clearly detailed procedure, as well as mine, turning Max Battery OFF did NOT reduce power delivery, which goes against your theory that it does.

By the way, I'm not trying to argue just for the sake of it - I'm just trying to understand the behavior of the car based on observations.

With max battery on the car makes more power I did not test / record any of the power numbers with max power on yesterday

 

[Old Man Mike]

By the way, I'm not trying to argue just for the sake of it - I'm just trying to understand the behavior of the car based on observations.

Look again at the graph. The maximum power anyone has ever obtained with Max battery off, even when the battery is hot, is 482 kw. With Max battery ON levels are well above 500 kw.

With Max battery OFF, the software limits the current even though the battery can deliver more. In fact, the V2 battery has enough margin that unlike previous batteries, the current limit results in the car having a constant max power level from 70 to 100%. The older P90D battery has just a little bit of margin which is why the effect is much less and converges around 85%.

Max Battery ON does two things:

1) It brings the battery up to the optimum temp.
2) It increase the max current limit to a higher level.

 

[MarcG]

With max battery on the car makes more power I did not test / record any of the power numbers with max power on yesterday

Ah ok, I thought you were saying that your car was producing the same power numbers with or without Max Battery. I think punctuation might help understand your posts better

 

[MarcG]

Look again at the graph. The maximum power anyone has ever obtained with Max battery off, even when the battery is hot, is 482 kw. With Max battery ON levels are well above 500 kw

Do you have data from the same v2 car with and without Max Battery during the same sessions? I guess Tech_Guy should be able to provide us some in his next run.
Just want to make sure data sets are valid for the same battery in the same environment (that's how you can scientifically derive proper conclusions.)

 

[Old Man Mike]

Do you have data from the same v2 car with and without Max Battery during the same sessions? ...

On the graph, the right most point for Max Batt Pwr ON is 511 kw and is from Tech_Guy's v2 car. That's why I considered his Max Batt Pwr OFF data with preheated battery so significant. As for scientific methods, I try to be very careful in collecting and graphing data. 50 years in the engineering field has pushed me toward that objective but I can still make mistakes and will always listen to opposing opinions.

 

[MarcG]

On the graph, the right most point for Max Batt Pwr ON is 511 kw and is from Tech_Guy's v2 car. That's why I considered his Max Batt Pwr OFF data with preheated battery so significant. As for scientific methods, I try to be very careful in collecting and graphing data. 50 years in the engineering field has pushed me toward that objective but I can still make mistakes and will always listen to opposing opinions.

Good to hear! I would definitely be interested in seeing Tech_Guy's results with the methodology you described.

 

[jerjozwik]

hmmm. i thought i posted on this thread with my info... i have yet to get to max battery ready with higher than 90% SoC. but still my car seems to be between the lines of the newer battery and the old one.

best Kw i have seen yet are 472 and 483. 80% and 90%.

i did get a lot of blinking orange ! triangle when doing max battery heating, so i dont think ill be running anymore high SoC max battery heating.

 

[Old Man Mike]

hmmm. i thought i posted on this thread with my info... i have yet to get to max battery ready with higher than 90% SoC. but still my car seems to be between the lines of the newer battery and the old one.

best Kw i have seen yet are 472 and 483. 80% and 90%.

i did get a lot of blinking orange ! triangle when doing max battery heating, so i dont think ill be running anymore high SoC max battery heating.

Your results are exactly what I would expect if you have the V2 battery but your Max Batt Pwr function is not working. In that case you would be limited to the power of Max Batt Pwr OFF which is just over 480 kw. Since you are getting a blinking orange triangle when you have Max Batt Pwr ON, it certainly suggest that also.

Sounds like you need to talk to service.

 

[jerjozwik]

max power on, but not ready.

 

[Old Man Mike]

I have three data points on the new P100DL S model and have made an abbreviated graph showing just the P90DLs and P100DL:

Note: I added an estimated point to produce a curve that is similar to previous batteries. This point will be replaced once additional data is obtained (hopefully in a couple of days).