Tesla plans to sell Model S and Model X electric cars with a battery pack option that squeezes more energy into the vehicles, giving them a longer driving range than previously offered and helping the cars accelerate more quickly.
The electric car company announced on Tuesday that it would sell a 100 kilowatt-hour battery pack for the high end Model S and Model X cars that would increase the distance they could travel on a single charge to 315 miles and 289 miles respectively.
With the new batteries, the high performance Model S is “the third fastest accelerating production car ever produced,” said Tesla. This version of the Model S is also “the longest range production electric vehicle by far,” Tesla added in an online post.
The news shows how Tesla is continuously trying to improve its current electric cars, and is also looking to make more higher-end versions that can bring the company more revenue before it introduces new models.
For an inside look at Tesla’s battery factory watch our video.
Previously, Tesla’s most energy-dense car battery was 90 kilowatt-hours that gave the high-end Model S a driving range of nearly 300 miles on a single charge.
While Tesla plans to offer the more energy-dense battery packs initially only for high-end versions of the Model S and Model X cars with “ludicrous mode”—now called the P100D, the company also plans to eventually make the 100-kilowatt hour batteries for its basic Model S and Model X cars.
On a call, Tesla CEO Elon Musk said that it would be “several months” before Tesla could offer the 100 kilowatt-hour battery pack for the basic versions of its cars. That’s because the 100 kilowatt-hour battery pack currently costs more to make and is in limited production.
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Musk and Tesla chief technology officer JB Straubel said on a call that the 100 kilowatt-hour battery pack was the same size as the less powerful version and that it used the same types of battery cells. But he said that the battery pack’s design is new, including a new way to cool the battery cells as they discharge energy.
The new battery pack has been “quite a challenging development,” and “the manufacturing complexity is significantly greater” than the less-energy dense battery packs, said Musk.
For Tesla’s Model 3, the company plans to use new bigger battery cells that are produced at its battery factory outside of Reno, Nev. Tesla plans to start shipping the Model 3 at the end of 2017.
The company has been investing heavily this year in building its battery factory and getting ready to produce the Model 3. This quarter, Tesla has $1.1 billion in cash requirements for payments and planned expenditures.
For customers that have already ordered a Model S or Model X P90D with Ludicrous mode, but haven’t yet received the car, Tesla will sell the 100 kilowatt battery upgrade for $10,000. Customers that already have received a P90D from Tesla can get the upgrade for $20,000.