My destination northbound is north Lake Tahoe. Southbound from Tahoe, destination is Huntington Beach. Maybe it has some algorithm to ignore short hops, but no matter, Nav should not force a long supercharge to high SOC at Mammoth lakes in order to skip a SC 90 miles away. When I sit at Mammoth lakes and press the lightning icon Nav does not show Gardnerville/Topaz Lake as one of the available SC, although it does show Hawthorne, NV and one west of Yosemite.
Aim to arrive at a Super Charger with no less than 10% and charge to no more than 80% unless absolutely necessary. It is a faster charge, reduces down time and is better for the battery.
Do you mean "arrive at ... no more than 10%"? If I can safely roll in at 3% I will. That's possible where the land is flat and the weather is consistent just by adjusting speed toward the end of the leg.
When I arrive with <10% it is my experience that charging starts relatively slowly and ramps up above 10% or so. So it doesn’t save time to charge less full and arrive that low. I presume that is done to protect nearly empty cells, and it may be different with newer batteries. Then there is the issue with headwind. We ran into this recently heading out of central Colorado north and then west on I80 in Wyoming. Speed limit is mostly 80 and we could see the arrival range clicking down from close to 20% to below 10% over 1-1/2 hrs. If I would have listened to the Tesla plan and charged less before leaving we would have had to slow down to <50 mph for quite a stretch, which can be dangerous in Wyoming with semi trucks passing you at 80+. I’ve learned to plan to arrive with 15% left, which is only a little over 30 miles range in our X90D. That way we can afford a small detour get a decent coffee before heading to the SC.
It should still charge pretty fast on your 90kW Tesla from 6-12%, but you are correct with that it does speed up. Here's an article on ABRP about the Supercharging speeds with various battery packs at different SOC%. Tesla Supercharging - Summer 2019 Update Here's your 90kW pack: I try to arrive at a SuC with 8-20% SOC and typically leave before I hit 75% on our old S85. My time is better spent driving towards my destination rather than waiting to charge at below 40kW...unless there's eating/drinking/shopping/site-seeing/conference call to be had.
Below 10% is a slower charge rate and also harder on the battery. Aim to arrive with approx. 10% . It is also less stressful than worrying about making it with 3% or less.
There's an anti-bricking buffer at the low end, so as far as the battery chemistry is concerned it's something like 8%. I have my car to use it, not to baby the battery, so that lowest % is there to use if I need it. Now keeping the battery sitting at 3% for long periods is definitely abuse, not use. Just my perspective. FWIW, 2015 S70, 31k miles with about 15% of that road trips,and zero degradation.
I run the battery down that low (3%) about 6 days a year, roughly 4 times each day, for the last 3 years, for a total of 72 times during 50,000 miles of driving. Current degradation on the S70D battery is 3.75%, if you can trust the Tesla 'range miles' that the car reports. I'm expecting 0.5% annual degradation over the next 10 years. I also keep the battery at an average of around 72% SOC over a continuous 12 month period, rarely charging above 80%, and chiefly relying on 1.0 kW charging.