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Is the 10% degradation per scanmytesla and teslafi after only 7000 miles real?

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MY-Y

Active Member
Mar 4, 2020
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I've read many posts on this, including the tricks to help the BMS recalibrate. Both scanmytesla and teslafi say I've degraded 10% in just 7000 miles. I'm gentle on the battery, only charged above 90% a few times for a short period when it was cool out. I'm not worried, but am a little confused. Many folks seem to have minimal reported degradation. One more observation. The max charge my phone app lets me set is between 93% and 99% depending on how low I am. It will show a 100% max when I hit ~90% or so.

When I do the battery capacity calculation from the energy screen, I got ~72 kWh a couple of weeks ago before that sharp drop shown on Teslafi. Its a little below 70kWh right now.
Thoughts?
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I highly doubt your pack is experiencing that level of degradation, especially with such little DC charging.

I have a hunch that this is more related to how the BMS calculation of remaining capacity is effected by colder temperatures. It is already proven that cold temperatures will temporarily reduce the capacity, so I think it’s safe to assume that after months at cold temperatures, the BMS may lose calibration with the pack’s true capacity. After all, the new capacity is only achieved at a specific temperature range.
 
I’m showing 9% degradation after 9k miles and 5 months. I think it’s because I regularly cruise at 80mph with the AC on max. There was another thread of a guy living on top a hill that degraded fast. I’m suspecting these cars don’t do well if you require sustained high discharge loads. Do you drive lead footed?
 
That only takes about 35kW, or 0.5C. That’s not a high discharge load and not the cause of any significant degradation.
I did some quick math:

i use 15% of my batt in 30min. At that rate it would be fully discharged in 3.3hrs, which is about 3x the rate I charge it with a 220v 50amp circuit. Might not be as fast as supercharging but it’s getting close. I realize I’m mixing charging and discharging but it’s the best way I have to compare.
 
I admit I occasionally mash the pedal but even when I’m driving normally I feel like I have excess degradation. My 9% loss has been pretty evenly spread across the months I’ve owned it regardless of how much I use the acceleration.