In January 2007, the American automaker
Tesla Motors opened a facility in
Rochester Hills, Michigan, employing sixty people to work on new projects, including a four-door
sedan. Beginning development under the
codename WhiteStar, Tesla planned for the car to have two powertrain options. The first would be a battery-electric version with an
all-electric range of . The second was to be a
hybrid electric vehicle with a
range extender, capable of traveling between on electric power before a small
gasoline engine would recharge its batteries and power the vehicle, giving it a total range of . However, at the GoingGreen conference in September 2008,
Elon Musk—the
chief executive officer of Tesla—announced that the company would exclusively produce battery-electric vehicles. In 2007, Musk appointed
Henrik Fisker, known for his work with
Aston Martin, as the lead designer of the WhiteStar project. Fisker signed a US$875,000 contract to design the car. The company requested that he design a "sleek, four-door sedan" priced from $50,000–$70,000 (equivalent to $–$ in ), and that it be ready between late 2009 and early 2010. Fisker owned a design studio in
Orange County, California, which Tesla employees visited to view his designs. Their reactions were generally negative; Ron Lloyd, the vice president of the WhiteStar project, described the designs as "terrible [...] some of the early styles were like a giant egg". When Musk rejected his designs, Fisker attributed the decision to the project's physical constraints, saying, "they wouldn't let me make the car sexy". Shortly after the meetings, Fisker started
his own eponymous company and debuted the
Fisker Karma in 2008 at the
North American International Auto Show. Musk
filed a lawsuit against Fisker, accusing him of stealing Tesla's design ideas and using the $875,000 to launch his own company. Fisker won the lawsuit in November 2008, and an
arbitrator declared Tesla's claims to be without merit and ordered Tesla to reimburse Fisker's legal fees. A small team of Tesla engineers went to a
Mercedes-Benz car dealership where they test-drove a
CLS and an
E-Class. Both cars shared a
chassis, and the engineers assessed different aspects of the two vehicles, evaluating their positives and negatives. They ultimately preferred the CLS's styling and used it as the baseline for the Model S. After purchasing a CLS, they disassembled it, modified the
battery pack of a
Tesla Roadster, cut out the CLS's floor, and integrated it with the battery pack. They subsequently put all of its electronics and systems in the CLS's
trunk and replaced the interior. After three months of development, the engineers completed a battery-electric version of the CLS. They frequently tested the car on public roads. It had of all-electric range per charge and weighed more than the Roadster. In August 2008, Musk hired
Franz von Holzhausen—who formerly designed for
Mazda—as project WhiteStar's lead designer. Von Holzhausen reviewed Fisker's sketches and
clay models but was unimpressed with what he saw, stating that "it was clear[...] that the people [who] had been working on this were novices". To save money, Tesla established its design center within a factory for
SpaceX—a company also owned by Musk. As von Holzhausen began designing the exterior of the Model S, Tesla engineers initiated a project to construct another electric version of a CLS. They stripped it to its core, removed the body structure, and extended the
wheelbase by to align with early Model S specifications. Within three months, von Holzhausen had designed what would become the production Model S's exterior, and the engineers had begun building a
prototype around the design. Given the battery pack's substantial weight, Musk and the team began efforts to minimize the weight of other components. To address this issue, Musk opted to use
aluminum instead of
steel, stating that the non-battery-pack portion of the vehicle must be lighter than equivalent gasoline vehicles. He noted that the primary challenge was that if aluminum were not used in its construction, the car's performance would be compromised. To accelerate the development of the Model S, one group of engineers worked during the day, while another arrived late evening and worked through the night, both operating within a tent in the SpaceX factory. at the 2009
Frankfurt Motor Show Tesla debuted a prototype version of the Model S in
Hawthorne, California, on March 26, 2009. In August 2009,
J. B. Straubel stated that a battery pack with range would be available, a significant advance at the time. Tesla initially intended to manufacture the Model S in
Albuquerque, New Mexico, and later in
San Jose, California, but later withdrew from both plans mainly due to financial problems. During the
Great Recession, American automaker
General Motors decided to abandon the
NUMMI facility in 2009, with
Toyota soon following. A month after the last car was produced at the manufacturing line in April 2010, Toyota and Tesla announced a partnership and the transfer of the factory. Tesla agreed to purchase a significant portion of the facility for $42million (equivalent $million in ), while Toyota invested $50million (equivalent to $million in ) in Tesla for a 2.5percent stake in the company. During the early 2010s, Musk expanded the engineering teams for the Model S, while von Holzhausen grew the design teams in
Los Angeles. The engineers operated in a lab with forty-five personnel. The pre-production version of the Model S, featuring newly stamped body parts from the Fremont factory, a revamped battery pack, and improved
power electronics, was completed in the basement of an office in
Palo Alto, California. Twelve of the cars were produced; some were sent to suppliers such as
Bosch, while others were preserved for testing and design alterations. On June 22, 2012, Tesla invited its employees, select customers, and the press to see the first production Model S in Fremont. == Design ==