Really have no complaints with battery life so far - knock wood!
2017 Tesla Model S P100D - 9 years on the road, 202155 miles (purchased at 50K miles), range 86% of nominal. 270/315 miles
2015 Tesla Model S 85D - 11 years on the road, 125251 miles (purchased at 16K miles), range 90% of nominal. 244/270 miles
Both vehicles have free Supercharging, and that gets used a fair amount. Both now have home charging, but the 2015 was almost exclusively supercharged for about 3 years.
These battery packs have active cooling and heating, and an exceptionally good level of cell balancing, which doubtless helps with the longevity.
Also, in the 250K+ miles we've driven, we've had one unscheduled stop - a damaged tire. Biggest maintenance item so far was a failed cabin heater and leaking coolant valve on the P100D, that required them to drop the battery to fix it, the rest were several minor warranty repairs, a cracked suspension bushing on the 2015, replacing a rock-damaged windshield, and between the two vehicles there were some door handles and a trunk cinch actuator repaired or replaced. Most of the service work was done by "Tesla Rangers" in the driveway.
The P100D looks and drives like a two-or-three-year-old vehicle which has had a couple of curbside parking dings, the 85D looks and drives even better. I remember my first automobile - a 1970 Plymouth Duster, slant 6 engine, which had the engine's top end rebuilt at 75K miles and died utterly at 150K miles. Obviously a different class of vehicle, but it was thought of at the time as a vehicle which was so reliable it would outlast the owner - in comparison, it seemed to have been manufactured from empty soup cans and bailing wire - even the paint was mostly gone by 150K miles.