Tesla's Model S Breaks the 400-Mile Range Barrier for the First Time

author: FutureCar Staff    

The 400 mile range target is considered a significant milestone for automakers around the world developing electric vehicles. Tesla announced it made a number of small improvements to the Long Range Tesla Model S and announced it achieved the elusive 400-mile range target.

Electric automaker Tesla announced that the latest version of the Model S sedan achieved an official EPA estimated range of 402 miles, which is 20% higher than the Model S 100D with the same battery pack design. 

The 402-mile EPA range estimate is the highest for any version of the Model S since its introduction in 2012 and the upgrade over the years are significant. The original Model S introduced in 2012 had an EPA estimated range of 265 miles. The previous Long Range Model S received an EPA estimated range of 391 miles.

The Model S becomes the world's first production EV with an EPA estimated range of over 400 miles.

Over the years Tesla has been steadily making range improvements across its lineup, including OTA software upgrades in 2016 to boost the original 70 kWh Model S battery pack to 75 kWh. 

Tesla wrote in a blog post on Monday, "This significant achievement reflects Tesla's obsession with efficiency and energy frugality, and is realized through several changes, both iterative and transformational, in core hardware and system architecture development by the Tesla engineering, design and production teams." 

Tesla said the design changes went into production earlier this year at the company's Fremont California assembly plant. All Model S Long Range Plus vehicles will now receive the new 402-mile EPA rating.

Tesla announced that improvements in engineering, design and manufacturing of the Model 3 and Model Y crossover have now been carried over to Model S and Model X production. 

Among the improvements contributing to the longer range are significant reductions in weight. The Long Range Model S uses lighter weight materials in the battery pack and electric drive units, as well as in the seats, aided by what Tesla calls "the standardization of Tesla's in-house seat manufacturing." 

Tesla also improved its "Aero Wheels." The automaker's new "Tempest" Aero Wheels and tires reduce aerodynamic drag compared to the previous wheels on the Model S Long Range. When combined with low rolling resistance tires, the Aero Wheels add a 2% improvement to the overall range, Tesla said.

Among the engineering improvements not visible are to the Model S rear AC-induction drive unit. Tesla replaced the original mechanical oil pump with an electric one, which optimizes lubrication independent of vehicle speed to reduce friction. 

Further improvements to the gearbox in the Model S front permanent magnet synchronous reluctance motors have resulted in a further increase of 2% more range while driving on the highway. These improvements to the gearbox are shared with the Model 3 and Model Y. 

Another way automakers gain additional range from their EVs is the use of regenerative braking, which uses the resistance of the electric motors to slow the car and provide additional charge to the battery while braking. 

Tesla also developed a new feature called "HOLD", which combines the motor's regenerative braking with mechanical brakes to bring the Model S to a stop smoothly by a driver simply taking their foot off of the accelerator pedal. The regenerative braking in the Long Range Plus Model S now works at a lower speeds and deceleration rates, thereby sending more energy back to the battery pack, then the previous version.

The updated regenerative braking system can significantly extend the life of the mechanical braking setup, since there is less wear and tear on the friction materials.

While each of these system changes adds around 2% gain in efficiency, when combined together they add up, increasing the efficiency of Tesla's vehicles.

Model S Long Range Plus has also recently received a price reduction of $5,000. The version now starts at $74,990 in the U.S.

FutureCar Staff