Erik Nordeus - The Engineer

To make sure they got a working transmission they contacted two companies. If both designs worked well, they would pick the lower cost option 199,213In September 2008, Tesla chose the company BorgWarner to manufacture a single-speed transmission.

Coloring was easier when Henry Ford made cars. He told his customers they could choose whatever color they wanted as long as they chose black. Why black? Black was the color that dried the fastest. But the Roadster came in twelve colors and each color needed a special name. “Oh boy, the naming took some time,” a Tesla employee said. “After several PR and design people took a run at it, we held a competition amongst the employees. We were running out of time. Three Tesla Motors executives were dragged into a conference room and were not allowed out until each color had an agreed upon name.” So the Roadster got colors like Electric Blue or Sterling Silver. It turned out that Radiant Red was the most popular color among the customers. 270

The Roadster became more and more expensive and it took longer and longer to get it into production. “I always argued that we would sell exactly as many cars whether the door latches were push-button or electronic, whether the body panels were carbon fiber or fiberglass. All the nicer, cooler, faster stuff increased risk,” Eberhard said. But Elon disagreed. “I was very insistent on things during the design phase, and it is true those things cost money, but you can’t sell a $100 000 car that looks like crap,” Elon said. “On some of these changes I had to be quite forceful because Martin [Eberhard] didn’t want to spend the money.” 196,209

Because of all these changes, the Roadster and the Elise became two different cars. In hindsight, it would have been a better idea not to redesign the Elise. “We have the same airbag system,” Eberhard said. “We have a similar crash protection system. But it isn’t so much based on the Elise. There was maybe ten percent common parts to it in our cars. The windscreen, the airbag system, some of the surround, some of the rubber seals, that kind of thing. The chassis of the car is not a Lotus chassis and the body is clearly different than the Lotus body.” 200

Another part that differed from the Elise was the engine. Tesla decided to use a modern version of an engine developed by Nikola Tesla himself. With a diameter of 25 cm, the 250 hp engine would sit on the rear-axis. It weighed only 60 pounds [27 kg], which is considerable less compared with a regular gasoline engine.

The batteries needed to power the engine in a Tesla car are the same batteries as can be found in a laptop: lithium-ion batteries. These are the best batteries available for purchase and for installation in a car, and they will probably be so for a long time. “We looked at some of the other chemistries of batteries around and they’re either not available actually, you couldn’t actually buy some, which is a drawback to putting them in a car, or they have substantially lower energy density,” Eberhard said. “Energy density translates to shorter driving range, and for us driving range is one of the most important factors for an electric car to be successful.” 200This was one of the topics Elon and Eberhard didn’t disagree on. “Lithium-ion batteries are the most efficient way to store electricity today, but I suspect we will find that there are even better technologies down the road,” Elon said. 248

The final battery consisted of 6831 smaller cells. There are six to twelve of these cells in a common laptop battery. Compared with a regular lead-acid car battery, these batteries are lighter and more powerful, and they don’t contain any hazardous material. You can recycle a laptop battery in a similar way as a soda can, and Tesla joined a recycling company that will take care of used batteries. “I wouldn’t recommend them as a dessert topping, but the Tesla Motors lithium-ion cells are not classified as hazardous and are landfill safe,” Elon said. “However, dumping them in the trash would be throwing money away, since the battery pack can be sold to recycling companies.” 247

Everyone who has used a laptop knows that the performance of the battery will decrease as time goes by. But you can’t compare a laptop battery with the battery in an electric car. The difference between the Roadster and a laptop is that the laptop wasn’t designed to last several years. A laptop’s hardware will be obsolete after a few years, so why would the battery need to last longer? “I mean, Microsoft just conspired to make sure that your laptop is obsolete in five years and so if the battery pack poops out in five years that’s okay, that’s fine,” Eberhard said. 200

In a car it’s possible to optimize the battery’s life-length. One of the aspects affecting a battery’s life-length is the temperature around the battery. While the battery in a laptop is exposed to heat from the rest of the computer, the battery in a car will be cooled to an optimal temperature. 200

Another aspect affecting the life-length of a battery is how you charge it. The optimal way is not to charge the battery to 100 percent, as is often done with a laptop battery because the cord is always plugged in. To improve the life-length, Tesla developed algorithms to optimize the charging and discharging of the battery. 200

The risk of a failure in one of these batteries is low. Sony has made about eight billion lithium-ion cells so far, and only eight of those have caught fire. 355“You have them in smartphones and no one is worried about having those near sensitive parts,” Elon said. “It is also why arsonists tend to favor gasoline. Trying to set the side of a building on fire with a battery pack is far less effective.”

To be on the safe side, a Tesla battery consists of several cells. Tesla catastrophe tested the battery by heating individual cells until they burst into flames. If one cell overheats, it will not start a chain reaction explosion. Several sensors detects acceleration, deceleration, tilt, temperature, and smoke. If one sensor detects an abnormal event, like if the Roadster is involved in an accident, it immediately shuts down and disconnects the power system. “We had to think about all different types of crash scenarios,” Straubel said. “So there’s really a lot of what-if type of engineering.” 347

So to avoid peak oil, we just need to replace our gasoline vehicles with vehicles powered by lithium-ion batteries. But isn’t there a peak lithium like there’s a peak oil? It’s true that the supply of lithium is not endless, but if the price of lithium increases, then it will be profitable to extract lithium from sea water. According to research, there are 230 billion tonnes of lithium available in the sea. “There’s a lot of lithium in the world,” Straubel said. “Lithium gets talked about as the resource constraint in many cases, but there’s surprisingly small amounts of lithium in a lithium-ion battery. We are more concerned about nickel and cobalt.” 426

A battery pack in a Roadster will last for 100 000 miles [161 000 km] or seven years. After this time or distance, Tesla expects the battery pack will retain approximately 65 percent of its ability to hold the initial charge. 382It’s currently expensive to replace the batteries, but Tesla believes the price of the new batteries will decrease due to technological progress. “Technology in these batteries is constantly improving,” Straubel said. “It’s a pretty exciting thing from a car point of view. Lithium-ion batteries are getting better by maybe seven or eight percent every year. A little bit more energy and range, and also the cost is improving. So, it’s a very exciting time.” Electric vehicles ten years from now may thus have twice the range of today, or a battery pack that weighs half as much as the battery packs weighs today. 234