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Has anyone tested the decline of power on the P3 with the decline in total battery?
- Thread starter AndrewAllen
- Start date
Watts_Up
Well-Known Member
I'm not too much into drag racing but when watching some of them on Youtube, having a top SOC was always mentionned as a must.
Which make sense for a given max current, more voltage would give more power.
However, unless you are in a energy saving turtle mode, I wonder if it's something really noticeable?
Which make sense for a given max current, more voltage would give more power.
However, unless you are in a energy saving turtle mode, I wonder if it's something really noticeable?
Adrien
Member
I would be noticeable. Like you said Volts*Amps= Watts. Current is going to be hard limited at the top end. Voltage is basically the SOC. 4.15V at he top end quickly scaling back to 3.8V or so around 80% and then down from there fairly linearly. An S curve. Do the math and you're down 10% just at 80% and in the lower voltage levels down 25 even 30%. So yeah, to the OP, it should be noticeable.
Capacity and power are two different things. I can fill a 5 gallon bucket from a 1 gal/min tap or fill it from a 5 gal/min tap. Power in batteries is measured in watts, capacity in Ah or Wh which are related by the battery voltage.
It is to a small extent, but at the track a small difference matters. The wattage of the battery is the current times the voltage. The current available changes only a bit over most of the charge range, but the voltage changes more. When peak charged the voltage is perhaps 5% higher. The combined effect is noticeable when timing a run.
StealthP3D
Well-Known Member
I have a P3 and there is a barely discernible decline in acceleration at progressively lower charge levels. But it's really subtle because even at 20 % state of charge, the car is ungodly fast and will still take just about any combustion car off the line. By the time it gets down to 10% it's definitely noticeable (although it's still faster than most V-8's).
There's some good information and test results in this thread: P3D+ Acceleration
My experience on track suggess the P3D+ in track mode performs in a very similar way from 90% all the way to 10% at least. Looking at data I logged last time I tracked it, there was very little difference in top speeds at the end of the fastest straight (2-3mph tops) between 80% and 10%.
My experience on track suggess the P3D+ in track mode performs in a very similar way from 90% all the way to 10% at least. Looking at data I logged last time I tracked it, there was very little difference in top speeds at the end of the fastest straight (2-3mph tops) between 80% and 10%.
destructure00
Active Member
I've noticed significant drop in acceleration at the track below 30%. Below I think about 15% it really falls on its face.
Have you measured it with a data logger or are you going by feel?
What was the ambient temperature at the time?
I ran mine down to 10% a couple of weeks ago (chasing a F488 around) and the only way I knew I was so low was when I glanced at the display. The data I've got bears me out too.
There must be another difference between your experience and mine rather than just SOC alone.
destructure00
Active Member
Feel...number of people I pass and the ease at which I pass them. 2 track days with same results. Ambient temp probably around 90. I don't have any data to back it up but I'm 100% confident power is down quite a bit below 20%....30 may be too high. Below 10% the car is a complete dog.
Can't find the link but I did find this on reddit today Model 3 Performance Power vs. Speed per SOC (FW 2019.32.12.2) : teslamotors
