Battery degradation is a common concern for electric vehicle (EV) owners, but recent research suggests that modern batteries may outlast the lifespan of the vehicle itself. To put this theory to the test, Out of Spec Testing conducted a range test with a 2019 Tesla Model S with over 250,000 miles on the odometer.
Despite being less than 10 years old, this particular Tesla Model S has already racked up an impressive 250,000 miles. The car, equipped with a 75 kilowatt-hour battery pack and an EPA-rated range of 285 miles when new, is still running on what is believed to be its original battery pack.
Purchased used for just $9,000, including incentives, this high-mileage Tesla Model S is quite the bargain. What sets it apart from other high-mileage vehicles is the fact that it still has a battery warranty from Tesla. Pre-2020 Model S EVs came with an eight-year, unlimited mileage warranty for models with a battery pack larger than 70 kWh, providing the new owner with two more years of coverage.
For the range test, the Tesla Model S was fully charged and prepared for optimal efficiency. The car was equipped with the manufacturer’s recommended tire pressure, set to the lowest suspension height, and had the A/C set between 68 and 72 degrees. Additionally, Range Mode was activated, disconnecting the rear motor to make the car front-wheel drive for increased efficiency.
During the test, the car faced ambient temperatures ranging from 43 to 62 degrees, with 20 mph winds along the route. The car maintained a speed of 71 mph (70 mph on GPS) until it could no longer accelerate past 67 mph after 203 miles. The test concluded at 206 miles, using 57.8 kWh of energy at an average efficiency of 3.6 miles/kWh. For comparison, a 2023 Tesla Model 3 Long Range achieved 3.9 miles/kWh on the same test, showcasing the Model S’s efficiency despite its higher mileage.
The test revealed approximately 23% battery degradation after 250,000 miles, although the exact degradation rate is challenging to determine without knowledge of the original usable battery capacity. Nevertheless, the range loss observed in the Model S after 250,000 miles is not significant, highlighting the durability and longevity of modern EV batteries.