Although the current penetration rate of electric vehicles is far lower than that of fuel vehicles, the replacement of traditional fuel vehicles with new energy vehicles has been put on the agenda by many car companies.
Not long ago, Volvo Cars announced that it would be fully electrified by 2030 and become a pure electric vehicle brand.
Volkswagen has raised its electric vehicle sales target for this year to 1 million units, and plans that half of its total sales by 2030 will be pure electric vehicles.
BMW said at its financial report last week that by 2023, it will provide pure electric models in 90% of the market segments, and will deliver 10 million pure electric vehicles in the next ten years.
The future of electric vehicles is approaching, and in China, apart from a few major new car manufacturers, BYD has received the most attention in the field of new energy vehicles.
This manufacturer, which initially supplied batteries to Motorola, Nokia and other mobile phone manufacturers, surpassed Volkswagen to become the world’s third-largest car company by market value last year. Buffett’s 12-year holding of BYD’s stock has earned nearly 25 times, and it has also made the legend of "stock god" again one extra.
Recently Ai Faner also came to BYD's headquarters in Pingshan, Shenzhen, to see how they spent hundreds of millions to build and destroy cars, and what challenges the current new energy vehicles face.
Spend 250 million to "destroy a car", a dummy is more expensive than a house
Before I went to the BYD headquarters, I thought it would be an "automobile museum", showing us various types of BYD models. I didn't expect that I would see more car wrecks than new cars.
In BYD’s Automotive Safety Engineering Laboratory, it covers an area of 22,000 square meters and is divided into a frontal collision area, a central collision area and an outdoor collision area. According to BYD, the laboratory cost nearly 200 million to build.
Vehicles that have undergone collision tests in different scenarios were parked on a promenade in the laboratory. There are dozens of scrapped vehicles waiting to be pulled away outdoors.
According to BYD engineers, each model has to undergo hundreds of collision tests before it goes on the market. In addition to computer simulation of collisions, 50 or 60 physical collisions of the entire vehicle must be carried out.
Car safety testing is actually burning money. Taking BYD Hanev, which went on the market last year, as an example, 500 test vehicles were prepared, and the cost of the test vehicles exceeded 250 million.
But the most valuable thing in the crash test is not the car, but the dummy sitting in the car. The dummies I saw in the BYD dummy showroom cost more than 7 million. The dummies also need to be placed in the dummy showroom with a temperature between 20°C and 22°C. The entire set costs tens of millions. .
Expensive naturally makes sense. These dummies used for crash tests are not ordinary dolls. It is a highly simulated precision instrument that contains hundreds of parts and dozens of sensors, reproducing the human body structure including the head, bones, brain, and internal organs. A large number of sensors are used to capture the damage of various parts of the body after a collision. data.
At the same time, in order to restore the real situation of the car owner and passengers in the event of a collision, it is also necessary to make different dummies for different ages, genders, and physiques. In BYD’s dummy showroom, there are many types of dummy, from 30-day-old babies to adult males and females.
Compared with the birth of the car, the dummy used for the crash test actually appeared very late. The first crash test dummy, Sierra Sam, was born in 1949, and it was not used in the automotive industry at the beginning, but for the U.S. Air Force to test ejection chairs and seat belts.
▲ Sierra Sam, the first-generation crash test dummy.
Before that, car crash tests used corpses, animals, and even real people. Not only were the test samples not comprehensive enough, but they also faced huge ethical and moral pressure. These problems were gradually solved after the appearance of model dummies. These are expensive. "Puppets" have made a huge contribution to the reduction of car safety accident rates.
However, the arrival of new energy vehicles also poses new challenges for vehicle safety issues. There are many differences in the body structure of electric vehicles and fuel vehicles, and the biggest difference comes from the power system. Pure electric vehicles may not need an engine and a gearbox, but a battery pack instead.
Yang Feng, the product director of the Han series of BYD Automotive Engineering Research Institute, told Ai Faner that the current challenges facing new energy vehicles are mainly three:
1. Increased impact energy caused by high-pressure system and increased mass;
2. As the size of the battery increases, how to ensure that the battery core is 0 squeezed;
3. As battery energy density continues to increase, more comprehensive and more stringent design conditions are required;
It is not difficult to see that the safety of electric vehicles largely depends on the battery. This is also reflected in the three mandatory national standards issued by the Ministry of Industry and Information Technology for electric vehicles last year . The standards require that after a battery cell is thermally out of control, the battery system should not be fired or exploded within 5 minutes, and a safe escape is reserved for the occupants. time.
According to BYD engineers, the current standards for crash testing of electric vehicles are not uniform, and they generally set safety standards much higher than the basic standards.
Take BYD Han as an example, its military-grade hot-forming steel uses 43 materials, and the body hot-forming steel uses 97kg. The safety performance of the entire vehicle has reached the highest “L” level in the industry’s “LACU Strategy” (industry leader). status).
Blade battery and the future of new energy vehicles
In addition to crash tests, driving tests of vehicles in different road conditions are also indispensable. At the BYD Automobile and Parts Testing Center, I saw a vehicle called the "24-channel road simulation test bed," on which a car was being tested.
According to BYD engineers, the so-called “24-channel” means that forces and moments in 6 directions can be applied to 4 wheels, which can restore 95% of the real road conditions that may be encountered in daily driving. However, most car companies use 4-pillar test benches. It can restore 70% of the road conditions.
This also means that BYD can conduct more road conditions tests in a shorter period of time. For example, Han's test car has been tested on this platform for 3 rounds for 45 days, which is equivalent to the actual car driving 1 million kilometers on the test road.
In addition, I also saw BYD's battery safety test, which is the acupuncture experiment called "Mount Everest" in the battery experiment community.
The staff pierced the ternary lithium battery and BYD blade battery in the laboratory. They could see that the ternary lithium battery immediately emitted black smoke and exploded and caught fire, while the blade battery did not smoke or burn. At present, Tesla is included in the Most of the electric vehicles inside use ternary lithium batteries.
BYD Chairman Wang Chuanfu said last year that BYD blade batteries would completely erase the word "spontaneous combustion" from the dictionary of new energy vehicles.
The blade battery is a kind of lithium iron phosphate battery developed by BYD. The biggest difference is that it gets rid of the traditional battery module design. The single battery is directly elongated and fixed on the frame of the battery pack, which increases the battery space utilization from 40% to 60%, the overall energy density is increased by 50%, and the cost can be reduced by 30%.
▲ Blade battery.
At present, batteries of two materials are mainly used in the field of new energy vehicles, one is a ternary lithium battery, and the other is a lithium iron phosphate battery. The latter has a lower energy density than the former, but has improved safety and service life, while the blade battery improves the space utilization of the battery pack so that the lithium iron phosphate battery can achieve the same size as the three in the same volume. The battery life of the lithium battery is equivalent.
Tiger, a technician who has been engaged in battery research and development for many years, once told Ai Faner that the technical bottlenecks of batteries at this stage are mainly energy density, cycle life and temperature characteristics, which makes electric vehicles face greater problems in terms of mileage, safety, and cost.
Although the blade battery does not increase the energy density of the single battery, it does solve the problems of mileage, safety, and cost to a certain extent.
Regarding the innovation of battery technology, we also reported last year that Tesla released the electrodeless battery cell . Tesla used laser technology to remove the convex electrode structure of the traditional battery. The conductive coating directly contacts the battery end cover to reduce the current. The distance of movement and the reduction of internal resistance can increase the cell capacity by five times.
However, Tesla also attaches great importance to the improvement of production technology. For example, Tesla launched the largest single casting machine in history last year, allowing Model Y to be formed in one piece and reducing the cost of mass production again.
It can be seen that the research and development of battery materials and the refinement of production processes are indispensable for the development of electric vehicles. Either way, as long as they can enhance the experience of new energy vehicles and promote the popularization of electric vehicles, this is a meaningful innovation.
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