The early days of
Tesla The Roadster redefines the electric car
This article is an excerpt from
Tesla Motors:
How Elon Musk and Company Made Electric Cars Cool, and Sparked the Next Tech Revolution by Charged Senior Editor Charles Morris
This 270-page book is a comprehensive history of Tesla, told by the entrepreneurs who made it happen, as well as an assessment of the company’s lasting influence on the automotive industry and beyond. The new book is available on Amazon. For more information, see www.teslamotorsbook.com.
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he five visionaries who founded Tesla - Martin Eberhard, Marc Tarpenning, Elon Musk, JB Straubel and Ian Wright - were certainly greenies, and the environmental value of EVs was one of their prime motivators. However, they were also rocket scientists and sports car connoisseurs, and they were well aware of another advantage that electric powertrains have over internal combustion engines. Dinosaur-burning engines deliver peak torque (rotational force), and thus maximum acceleration, only within a limited range of RPMs - that’s one of the reasons for a multispeed transmission. An electric motor delivers maximum torque from the moment you step on the pedal, and is highly efficient throughout the rev range. The California company AC Propulsion had taken full advantage of this to build an EV called the tzero, which had a magic power: anyone who drove it instantly changed their opinion of electric cars. This was the rock that Musk and his Musketeers planned to build their company on. Shortly after Tesla was founded, Ian Wright negotiated a deal with AC Propulsion to license its motor and inverter technology. The tzero’s performance was impressive, but as the Tesla team worked with it, they found that there was a lot of room for improvement. Chief Engineer JB Straubel and his team ended up redesigning almost every part. Marc Tarpenning told me about the process of developing the custom-built tzero into a vehicle that could be mass-produced. “AC Propulsion had produced 60 drivetrains or something like that, all hand-crafted,” he said. “Each motor was matched with each inverter and they were all hand-tuned. This is not manufacturing, this is high-end hobbyist. It’s like when you buy an audio system from one of these places that makes a hundred stereos a year. We paid them a bunch of money to license [their motor] and we realized they couldn’t manufacture it, so we just designed our own motor which, in the end, was quite a bit different from what we started with.” According to Tarpenning, the Tesla team moved on from AC Propulsion’s motor pretty early in the game. “We redesigned it a year before we were in production. We did need one for the mule [the first test vehicle].