85 vs 90 kw battery - is the 90 worth the $3k cost?

Brunton said:

I've ordered a 90D, and it will confirm on Sunday. But I've been reading that the 90kwh battery apparently degrades a bit faster than the 85 does. That's left me wondering if the 90 is worth the additional cost.

How long can I expect to get the extra 14-15 mile range from the 90? How fast will it degrade to the equivalent 85? And is the degradation really a steeper curve than the 85? If so, how long before a 90 has less range than an equivalent-aged / used 85?

Anybody done any data collection on this?

Click to expand...

Tesla has indicated that it's a software error in measuring the 90kWh pack and not a true drop in capacity.

Until Tesla fixes the software, no one really knows what the degradation is really like. I suspect it will be fine once the software is updated.

+1 should be fine and Tesla backs it up.

Always get the bigger battery.

6% range increase (Tesla claims) is not worth it to me but my use case is likely different than yours. I basically drive to and from the airport each week and around town. I purchased my BMW in Dec 2013 and I just turned 13K miles. My car has never been outside of the greater Nashville area.

Get the larger battery. The resale bump alone will cover the $3K.

Honestly - after the P85D scandal I find it harder to trust Tesla when they say "no problem, it`s just software".
Maybe it`s just a software glitch. But reported usable kWh from the battery seems to be in line with the range drop, which could mean it`s not only a calculation issue.
But we won`t know for sure until Tesla fixes it, or months down the road with no fix and it becomes obvious that no fix will mend the problem.

Until they fix the potential initial plummet in 90D range I wouldn`t feel safe that the 6% range stays 6% better for more than a few months.
I have a 90D in production, so nothing I can do about it but trust Tesla to be truthful and fix the problem.
And at the same time hopefully fix the hvac which they ruined for cold places in the 7.0 sw.

On the bright side - The S85D seems to have very stable range numbers! Much more stable than my 2013 S85 had!

Oyvind.H said:

Maybe it`s just a software glitch. But reported usable kWh from the battery seems to be in line with the range drop, which could mean it`s not only a calculation issue.

Click to expand...

Oyvind, please provide your source for this. As you know I'm pretty on top of this myself and have never seen data to support this statement. Lots of speculation but no repeatable, specific and understandable data for the 90D.

I decided to go with the tried and true chemistry of the 85D rather than 90D. I believe the 90D is technically an 85kwh battery but they eeked out an additional 5Kwh with the new silicon anode chemistry. Only time will tell if the perceived/calculated rapid degradation in the 90D is real or not. The additional 6% range wasn't worth it to me. However, if there was a performance boost like the upgrade from 70 to 85, my decision would have been harder!

Anyway, once the silicon anode battery has been around longer, I'll upgrade to that P100DL