Autobiography of Tesla (I)

Let's talk about the news of Tesla's "falling door" in these two days. The actual configuration of the delivered vehicle is inconsistent with the relevant list, the consumer has not been informed, or it is suspected of fraud.

Just as the 3 15 Consumer Protection Day is coming, Tesla "does things" for himself. Are there any new domestic models? The owner found that the driving computer should be the latest version of the 3.0 chip hardware, while his car is the 2.5 version of the chip hardware. The image processing speed of the 3.0 version of the chip is 2 1 times that of the 2.5 version. In fact, these chips are used to support the Tesla driver-assisted driving system Autopilot, and the lower version of the hardware will directly affect the future function upgrade and vehicle driving experience.

After the distribution reduction was exposed, Tesla issued a statement as shown in the above figure, in which there was a sentence: "Tesla Giga Shanghai began to return to work on February 10. During the period, based on the supply chain situation, ... "Many netizens questioned why we should emphasize the resumption of work in February 10? Is this the latest "epidemic"?

Then, there are imported models? 3 car owners also found that their cars have this problem of reducing points.

Regarding this incident, some lawyers said, "If it is determined that Tesla's above-mentioned behavior conforms to the' fraudulent behavior' stipulated in Article 55 of the Consumer Protection Law, it will support the consumer's claim of' returning one and losing three'."

Next, continue the previous article "Tesla Motors? Biography (Part I)? |? How did this grinding goblin grow up? "Continue, Tesla follows the road map planned by Musk" Master? Plan ",that is, the" three-step "strategy, gradually developed.

First, build an expensive and niche roadster.

Second, use the money earned to build a cheaper car with medium sales volume (model? s/X)；

Third, use the money earned to build a more economical best-selling Model (model? 3);

Fourth, while doing the above, it also provides zero-emission power generation options.

What difficulties and challenges did Tesla experience in implementing this plan? What special things have you done?

The problem of production capacity has always been a problem.

Tesla keeps building super factories.

For any new automobile manufacturing force, production capacity is a thorny issue. It is not easy to assemble tens of thousands of parts into a car that can fly on the road!

Tesla, a new foreign car-making force, is no exception to this problem. As we mentioned earlier, the delivery time of Tesla's first car Roadster was greatly delayed because eberhard, the former CEO, paid too much attention to technology research and development and performance improvement, but neglected production arrangement and product control. More than 30 of the 65,438+0,000 scheduled users cancelled their orders because of the delivery delay. Originally, the sales volume was not much, and it could not be delivered on time, which made Tesla fall into embarrassment.

And then the model? S, model? X and Model3, which are already red and purple, Tesla's production capacity of each car can't keep up, and Tesla produced by order system has almost no inventory, which makes its new users always be prepared for delivery delay.

As for the reason for the delay in delivery, is it an early model? S internal repair rate is too high, or the highly automated production line is not debugged properly. Undoubtedly, the production system is immature and the production line is insufficient. In the face of increasingly fierce demand, Tesla is also increasing its production capacity and opening more production lines to meet the demand.

At present, Tesla has five factories around the world, and 1 is under construction. Every factory has a highly automated production capacity. In the constant running-in, Tesla gradually makes the robots on the production line work more effectively.

Fremont factory was rebuilt by Tesla on 20 10, which is the NUMMI factory mentioned in the last article. It belonged to Toyota before the acquisition. 20 12? The sixth year? In June, the first model made by Tesla? S is offline here. This super factory has the largest Shule in America? SMG? Hydraulic press, a welding manipulator specially built for Tesla, and nearly 500 robots built for KUKA production line. Although there is a highly automated production line, the total area of this 20 16 expansion is 93? In the 10000 square meter factory, there are still more than 1000 workers working here. Does the factory produce models at the same time? x？ , model? 3 of the finished car.

Fremont Factory (California, USA)

By 2020, Tesla will produce 500,000 yuan a year? With the grand plan of one car, Tesla's own battery demand has reached the global supply of lithium-ion batteries, and it is estimated that it needs to produce 35GWh power batteries every year.

Where's Gigafactory? 1? The factory was born for mass production of batteries and power supply systems. The factory manufactures auto parts such as power batteries, Model3 motors and electric drive axles, and may establish auto production lines in the future.

Gigafactory？ 1 (Nevada, USA)

Gigafactory？ 1 The factory started construction on July 20 14, which is the joint efforts of Tesla and Song. The whole factory is divided into two parts, one is battery produced by Panasonic, and the other is battery module and battery pack production line of Tesla. The perfect combination of the two directly reduces the production cost of the battery pack by 30%. Gigafactory？ 1 has started mass production of lithium-ion batteries. By the end of 20 18, Tesla's battery production capacity has reached 24GWh/ year. At present, some large battery factories in the world only produce about 4GWh lithium-ion batteries every year. At present, the factory is only 30% completed, which may become the largest building in the world.

"Accelerating the world's transition to sustainable energy" is Tesla's vision. In the above article, we also introduced Musk's roadmap for Tesla's development, "Master? Plan ",the last item is to provide zero-emission power generation options. Where's Gigafactory? The factory serves the plan.

Gigafactory？ 2 (new york, USA)

Gigafactory？ The factory is also jointly operated by Tesla and Panasonic, mainly for the joint production of solar energy? Solar panels and batteries on the roof.

Gigafactory？ 3 (China)

Tesla China Super Factory was built in 20 19, and the construction of German Super Factory just started not long ago. Therefore, it does not belong to Tesla's first ten-year plan. We will introduce it in detail in the next article, and put forward it here to let everyone have a complete understanding of Tesla's overall production scale.

Tilburg Assembly Plant (Netherlands)

Tilburg assembly plant is Tesla's first factory in Europe. The factory was put into production in August, 20 13, and the expansion was completed and started in October, 20 15. Tesla can model? S and Model? The parts of the X model were shipped to the Netherlands, where the final assembly was completed and then sold to Europe. The factory will be limited to vehicle assembly business and will not involve parts or system manufacturing.

With the continuous improvement of Tesla's production line, it is also gradually increasing its production capacity and moving towards global car companies.

Special issue 1

Use notebook battery as power supply?

The battery system accounts for 30%-40% of the cost of an electric car, which is the most important. So how did Tesla build this "source of energy"?

Tesla model dismantled by foreign media? s？ Battery system

Tesla power battery system includes battery core, battery management system (BMS), thermal management system and cooling management. Among them, the battery monomer accounts for more than 70% of the cost of the power battery system.

Let's talk about the battery that occupies the largest share of the power battery system. Tesla has used two kinds of cylindrical batteries, 18650 and 2 170. At present, the latest 2 170 cylindrical battery adopts nickel-cobalt-aluminum NCA with silicon-carbon negative electrode. The battery capacity is between 3 ~ 3 ~ 4.8 ah, and the energy density of the battery can reach 300Wh/kg, which is 250 Wh/ higher than that of the previous generation 18650 battery.

18650 cylindrical battery (diameter1.8cm, height 6.5cm, 0 stands for cylindrical)

In 20 13, when most electric vehicle OEMs were still stuck in lithium iron phosphate batteries and NCM11,Tesla had already started working on the Model? NCA ternary lithium battery with high energy density is used on s; When most manufacturers in the market began to transition from low-nickel materials to NCM622/NCM8 1 1 high-nickel cathode materials in 20 17, Tesla has explored the application of silicon-carbon cathode with higher energy density, and Tesla battery technology and vehicle cruising range have always been ahead of the industry.

2 170 cylindrical battery (i.e. 2 1700 battery, diameter 2. 1cm, height 70cm, 0 stands for cylindrical).

These batteries currently used by Tesla are all produced and supplied by Panasonic. These Panasonic batteries are not mysterious. Many lithium batteries of notebook computers in the market are packaged with this battery, and the production process is very mature.

Disassembly of traditional notebook battery

The lithium battery pack of notebook computer probably encapsulates 6 or 8 18650 cylindrical batteries; And the Tesla model? s？ For example, 85 needs more than 7000 identical batteries.

These batteries are packaged in groups and finally packaged into a whole by series-parallel connection. At the same time, due to the nonlinear discharge characteristics of lithium batteries, excessive charging and discharging of a single battery cell will cause permanent damage to the battery, which will lead to the instability of voltage and temperature of the whole battery system and serious thermal runaway events.

According to the order of "single battery-brick-chip-package", hierarchical management is carried out.

Tesla's battery management system is much more accurate than that of the same industry. According to foreign media, models? 3. Disassembly of the model? 3 BMS can control the voltage difference of 23-25 independent battery packs at 2-3mV, which is much lower than other ordinary electric vehicles. At the same time, the battery management system is highly integrated, and Tesla BMS module integrates high-voltage controller, DC converter and multiple sensors, thus reducing the high-voltage wiring harness required for internal communication, and ultimately reducing the total weight and cost.

Tesla model? s？ Battery disassembly

But speaking of which, do you have any questions? Will the battery of notebook computer heat up after use, and some notebooks will even burn up after being used for a long time, so isn't this more than 7 thousand battery a huge heat source? No wonder @ # Since #%&; ? * Burning @? ...？ ... but in winter, low temperature will also greatly affect battery efficiency! Ok, let's talk about his battery thermal management system.

In terms of battery thermal management, Tesla adopts a liquid cooling scheme with 50% water and 50% ethylene glycol as coolant, and realizes the series-parallel structure of motor and battery cooling cycle through a four-way valve. Controlled by the system-on-chip algorithm, when the battery temperature exceeds the set target value, the battery cycle and the motor cycle are independent of each other, and the battery is cooled in parallel; When the battery temperature is lower than the set target value, the battery cycle and the motor cycle are connected in series, the battery and the carriage are heated by the waste heat of the motor, and the excess heat will be discharged by the heat exchanger at the air inlet.

This scheme makes full use of the heat of all parts in the car, so that the heat can be effectively circulated, which greatly improves the heat dissipation of batteries and the temperature consistency between batteries. Therefore, regardless of the extreme climate in winter or summer, the temperature difference control of Tesla vehicles is kept within 2℃, showing strong temperature control ability.

Later, Tesla upgraded the battery, and the ignition point was reduced from about 175℃ of 18650 battery to about 65-82℃ of 2 170 battery, which put forward higher requirements for the battery cooling system. Compare the old models? s？ 85. New style? s？ P 100 and model? It can be found that the battery cooling system is upgraded in stages, from the early single cooling zone to each independent cooling zone, which provides better temperature control for the new version of 2 170 battery and greatly improves the battery cooling efficiency.

Special function 2

Adopt a niche motor

Unlike the permanent magnet synchronous motor used in the mainstream vehicle market, Tesla chose an induction motor with high manufacturing cost. If a simple comparison is made, it can be understood that the efficiency of permanent magnet motor is higher and the performance of induction motor is stronger.

Tesla electrical engineer

In addition to more powerful battery support, Tesla can sacrifice part of the motor efficiency selection performance, and Tesla's choice of induction motor has a lot to do with its original technology. In the story of the founder mentioned above, we mentioned AC, which first provided technical assistance and cooperation for eberhard and Tabenning. Propulsion company has leading technical strength in induction motors; In addition, the demagnetization risk of induction motor is small and the technology is mature; Moreover, permanent magnet synchronous motors need more rare earth materials, and the global rare earth capital is basically concentrated in East Asia, especially in China and Japan, which will bring procurement obstacles. Considering comprehensively, Tesla chose to carry an induction motor.

Tesla? Model3 dual-motor four-wheel drive version

Of course, Tesla also made a series of improvements to induction motor technology in the later period, including designing corresponding punching pieces, increasing torque, cooling system and other means, among which the most innovative is the patented technology of induction motor copper core rotor.

Tesla filled the gap of copper bar rotor slot with silver-plated copper sheet, then reinforced both ends and sealed the ring plate, which reduced the casting difficulty, improved the operation efficiency of the motor and completed the special power transformation of Tesla.

Tesla also tried on permanent magnet motors. In the previous Model3 rear-drive long-life model, the single-motor configuration of permanent magnet switched reluctance motor was adopted. Tesla's permanent magnet motor adopts the oil-cooled mode only possessed by a few large manufacturers in the world. After technical improvement, the speed can reach 18000 rpm, far exceeding the average level of 12000 rpm in the domestic market. Even if there are relatively high-tech manufacturers, it can only reach 15000 rpm. However, Tesla later abolished all two-wheel drive models based on the global model layout and sales strategy.

Special issue 3

Put the car on the computer?

In Bian Xiao's view, apart from promoting advanced pure electric vehicle technology, the most important thing is that Tesla has created OTA upgrade service in the automobile industry, which can be said to be a subversion of after-sales service.

Did a famous American automobile media point out the Tesla model? There is a problem that the braking distance is too long, causing an uproar. If it is a traditional car company, to solve similar situations, it is necessary to recall vehicles on a large scale or replace parts through 4S shops. Both schemes need to waste a long waiting time for car owners, and car companies have to pay huge economic losses for this. However, Tesla's engineers upgraded the system through OTA (over-the-air download) and solved the problem within a few days.

This is the most fundamental difference between Tesla and traditional car companies. Tesla can perform system upgrade (OTA) like a smartphone. The OTA of traditional car companies is limited to the car navigation function, and it is completely impossible to remotely control or upgrade the functions related to vehicle parts such as temperature, braking and charging in the car like Tesla.

The deeper reason behind it is that the underlying electronic and electrical architecture is completely different. The ECU development of all parts of traditional automobile enterprises is completed by suppliers, so each part has its own underlying code and authority restrictions. After being assembled into a complete vehicle, huge and complicated codes cannot be managed in a unified way, and suppliers may not necessarily provide code permissions to automobile enterprises, let alone upgrade them. This makes the update of automobile software almost synchronous with the automobile life cycle, which greatly affects the user experience.

Different from the traditional car building, Tesla adopts a centralized electronic and electrical architecture, that is, through independent research and development of the underlying operating system, the central processor is used to uniformly manage processors and ECU in different domains. This architecture is very similar to smartphones and PCs.

Take the electronic and electrical architecture of Tesla Model3 as an example, which is divided into three parts, CCM (Central Computing Module) and BCM? Left Body Control Module and BCM? RH (Right Body Control Module), in which CCM consists of IVI (Infotainment System), ADAS/Autopilot (Assisted Driving System) and communication inside and outside the vehicle, X86? Linux system. BCM？ LH and BCM? RH is responsible for the functions of body and convenience system, chassis and safety system and power system.

Such 3C modular development facilitates the application of OTA, makes the future software update and system iteration of vehicles easier, and can continuously provide the operation and service after vehicle delivery. The delivery of traditional automobile products means the beginning of loss and depreciation, but the software OTA gives the car more vitality and brings better user experience. Of course, the substantial optimization of the electronic wiring harness structure in the car has also brought more convenient production operation and improved production efficiency.

Since model 20 12? Since the launch of S, Tesla software system has been updated nine times, once every few months on average, and more than 50 functions have been added and improved, including automatic assisted driving, battery preheating, automatic parking and other functions. If Tesla only competes with traditional car companies in the same dimension in the field of three-power system, then the OTA of the whole vehicle belongs to Tesla's dimension reduction blow to traditional car companies and even traditional car first-class suppliers.

In 20 18, Volkswagen CEO Edith clearly proposed to build the public. OS operating system, and traditional car companies are beginning to realize the trend of technological change. However, compared with Tesla, who was born in Silicon Valley, software development is obviously not the strength of the public. We will wait and see how it will perform in the future.

As a faithful believer of first principles, Musk is good at returning to the essence of things to analyze and solve problems, rather than adopting analogy and improvement. Tesla has indeed won the market recognition with advanced technology and ideas, but how will it develop in the future? Next, let's talk about Tesla's second ten-year plan. See you next time!

This article comes from car home, the author of the car manufacturer, and does not represent car home's position.