With a number of new upgrades announced today, Tesla's Model S is now the third-fastest car in the world, going from 0 to 60 MPH in just 2.5 seconds. That's only just slower than the Ferrari LaFerrari and the Porsche 918 Spyder — both million-dollar hypercars. The Model X goes faster too, from 0-60MPH in 2.9 seconds, down from 3.2 seconds.

The added speed is thanks to a long-rumored 100kWh battery option, available for order today in its Model S and Model X cars. The new battery, which includes an additional 10kWh of storage over the previous top-of-the-line model, will deliver 315 miles of EPA-estimated range in the Model S P100D version, up from 294 miles when equipped with the 90kWh battery, and an increase of around seven percent. The Model X P100D rates 289 miles, up from 250 miles. The battery will only be available in the performance, all-wheel-drive model with the Ludicrous Mode option.

Tesla Model S can go from 0-60MPH in 2.5 seconds

Tesla said there were some upgrades made to the wiring harness and other small differences, but the drivetrain remains the same. The improvements to Ludicrous Mode acceleration are basically entirely due to the improvements in the battery pack. The biggest differences in day-to-day driving, says Tesla, is in highway-passing speeds where the car is typically limited by power.

The 100kWh battery will, naturally, come at a price. The Model S P100D with Ludicrous Mode will start at $134,500, an increase of $9,500 over the old P90D. It will be available for order immediately with the first deliveries beginning next month. A similarly equipped Model X starts at $135,500. Tesla said that the initial production run will be "limited" to around 200 packs per week, around 10 percent of total Tesla volume, and production will be increased going forward. It will likely be "several months" until Tesla offers the 100kWh battery pack in other trim levels.

This means Tesla’s current lineup includes Model S and Model X cars with 60kWh, 75kWh, 90kWh, and 100kWh battery options. Depending on which battery is purchased, base model pricing ranges from $66,000 to $134,500 on the Model S, and $74,000 to $135,500 on the Model X.

Tesla noted in its blog post that while the P100D Ludicrous "is obviously an expensive vehicle," sales will help pay for Model 3 development.

sales will help pay for development of the Model 3

Though the new battery pack uses the same cell technology, Tesla executives touted the advancements in the battery pack technology itself as significant. "It's a pretty big change in the battery module and pack technology," said JB Straubel, CTO of Tesla, on a call with reporters. "It's a complete redo on the cooling architecture."

The 90kWh pack was introduced a little more than a year ago, while a 75kWh battery pack was launched earlier this year. That 75kWh battery is especially interesting because it’s actually identical to the battery available in the 60kWh Tesla Model S, but the additional cells are locked by the vehicle’s software. Customers can pay to "unlock" that additional battery capacity after they buy the car. The 100kWh pack is not an unlockable upgrade, but an entirely new piece of hardware.

Tesla buyers who have ordered a P90D with Ludicrous Mode but not taken delivery will be able to upgrade to the P100D for $10,000, while owners of current P90D vehicles with Ludicrous Mode will be able to replace their existing battery pack for $20,000. In that case, the old pack will be recycled.

Along with the new battery, Tesla is also bringing the Premium Seats, currently available in the Model X to performance builds of the Model S.

Tesla Model X hands on