On July 18th, 2011, three months before Zhongtai electric vehicle â€œHangzhou spontaneously ignitedâ€, a pure electric 825 bus in Shanghai passed spontaneous combustion while passing through Zhongshan Park. In a subsequent investigation by the reporter, the electric vehicle spontaneously ignited. The phenomenon is not uncommon. As a result, people in the industry are shouting that China's electric vehicles must learn the lessons from the "high-speed rail." The development model of the "Great Leap Forward" must be slowed down, and electric vehicle demonstration operations must be standardized.
As an emerging industry, electric vehicles have been full of controversy. There are still many controversies regarding the formulation of power battery standards, the fact that power batteries themselves should produce cylindrical batteries and square batteries, and the commercial operation modes of electric vehicles.
A detail is worth noting, just after the State Grid set up a power exchange-based business model at the beginning of the year, China Southern Power Grid also announced on July 22 that it will mainly rely on the exchange of electricity.
Since the State Grid Corporation has been pushing for power change in Hangzhou, Zhongtai has provided bare cars in Hangzhou, and the batteries are the batteries of the Wanxiang Group purchased by the subordinate operators of State Grid. In the catalogue submitted by Zhongtai to the National Development and Reform Commission, Zhongtai Electric Vehicles uses The battery of China National Aviation Lithium Battery, which once again triggered the industry's thinking about changing mode.
The newspaper specially interviewed Wang Binggang, head of the supervision consulting expert group for national energy conservation and new energy automobile major projects of the National 863 Program, power lithium battery experts, Dong Ming, chairman of Hengzheng Technology (Suzhou) Co., Ltd., and Xie Zicong, an electric vehicle business model researcher.
The quality certification system needs to be established. Reporter: According to your analysis, what are the reasons for the spontaneous combustion of electric vehicles in Hangzhou and Shanghai?
Wang Binggang: The matter of Hangzhou shows that there are still problems in the design and technical aspects of battery grouping, and it is incomplete. Fortunately for now, no one is harmed.
I have visited the battery company's production line. The management is very rough and the dust is very large. Workers can touch the electrode pads by hand and leave sweat and dirt on them. These should not be allowed. Each time the battery is charged or replaced, it is the process of electrochemical material conversion. During the process of work, the battery itself expands and shrinks. If there is dirt, the diaphragm of the battery will be damaged sooner or later, and the diaphragm will be short-circuited. Will cause combustion. There are also some battery materials that have not undergone a very rigorous review. They are simply designed and invented for direct use. This type of battery burns even more.
Dong Ming: I did not participate in the accident investigation and cannot judge the root cause of the accident. However, the accidents in Shanghai and Hangzhou proved that the lithium iron phosphate battery is relatively safe and reliable. If it is a lithium battery using other cathode materials, it is not just a fire, but an explosion.
In addition, I think battery leakage is the direct cause of battery ignition. One of the important reasons is that, during the use of the battery, the internal temperature of the battery is too high and the pressure is too high, causing the electrolyte solution to leak out, and burning in contact with the air and the heat source.
Xie Zicong: The reason for this spontaneous combustion is that the process and detection system for battery grouping is not perfect. Now everyone knows about the standard of the electric vehicle's power battery and his quality system inspection system, and so on. He always kneads the single battery and the power battery to see the problem. Our country's current detection standard single cell battery detection is more, but how to identify the safety of the battery after grouping, we must establish a stringent testing standard for the corresponding power battery.
Reporter: I know that you have also done a lot of matching for electric vehicle batteries. How can you do it even if it leaks?
Dong Ming: In the past sixty-seven years, we have participated in supporting thousands of electric vehicles at home and abroad, and we have already spent 1,000 tons of positive electrode materials. No spontaneous combustion occurred. Mainly because we use low-resistance battery materials to make cylindrical batteries with thermal runaway protection. At present, the standard cylindrical battery structure design is relatively mature, there are many self-precaution mechanisms, considering that if the battery is overheated, if there are various problems, including battery leakage, the battery itself how to ensure that it does not catch fire; and most of the square battery design does not consider these factors There is no such self-prevention mechanism on the structure, and it is prone to thermal runaway, and it is easier to catch fire when it leaks. The square battery has a large volume and is more destructive after a fire.
Power Battery Fighter Reporter: How to Understand the Spontaneous Combustion Events in Shanghai? It is understood that this time the manufacturer of self-ignition bus Lei Bo is also using a cylindrical battery, and before your company also supplied cylindrical batteries to Shanghai electric cars?
Dong Ming: Shanghai 825 electric vehicle was put into commercial operation in 2007. The first batch of vehicles was 20 buses. The raw material of the battery was provided by our Hengzheng Technology. I also participated in coordinating the production of single cells. We used cylindrical columns. The 26650 battery, each single cell battery is done very carefully, the combination of modules is also very careful, individual monomer problems, it will not cause the entire system to catch fire. The new problem that arises now is that the currently used cylindrical battery does not have the necessary preventive mechanism or preventive mechanism.
Reporter: Why does the prevention mechanism fail now?
Dong Ming: I dismantled and analyzed many cylindrical batteries on the market and found that although the structures are similar, some preventive functions are no longer available. This is because some companies have forced themselves to reduce their quality requirements because of cost, competitive pressure, or lack of understanding of prevention capabilities.
Reporter: Does Zhongtai have a square battery?
Dong Ming: Yes, and the current mainstream of China is still a square battery. The mainstream of Europe and the United States is cylindrical.
Reporter: Why is the domestic mainstream being square?
Dong Ming: Square batteries and round batteries have their own advantages. First of all, the threshold for the investment in square battery production equipment is low. Second, the square battery connection is relatively easy, the connection work can be reduced, and the cost of the assembly process is relatively low. Cylindrical battery assembly process is more complex, more difficult and costly. The technical difficulty of cylindrical batteries lies in the connection problem. Most professional solutions are technically protected, and not intended for use. Many of our combination units do not have this technology, so we chose the square direction.
Reporter: Internationally, what is the development trend of lithium batteries?
Dong Ming: Internationally, Lithium iron phosphate batteries are mainly made by Japanese Sony (SONY), which insists on cylindrical batteries. Saft (SAFT) originally made square batteries. After 2008, it turned to cylindrical batteries. American Valence and A123 also use cylinders for the Lord. Both the square battery and the cylindrical battery have problems in technical operation. The difficulty of the former is how to add a safety precaution mechanism in the system. The latter problem is the connection between the batteries.
Reporter: What kind of path will Chinese battery companies develop in the future?
Dong Ming: Certainly it is polarization. Some companies do big batteries, and some companies do small round batteries. It's hard to say who will absolutely win.
Reporter: Your company is also facing the pressure of cost. How to reduce costs without weakening the function?
Dong Ming: The right path should improve production efficiency, increase the rate of finished products and pass rate, and increase the rate of finished products from 50% to 80%. The cost will definitely drop sharply. However, when it comes to more than 90%, every one percentage point increase must be paid. Great efforts will be made to increase the rate of finished products, but anyone can say it, but it is not necessarily achievable. Whether it can be improved depends on technological advancement, improvement in the level of management and equipment.
For example, the production cost of South Korea's Samsung battery is lower than most battery factories in China. First, Samsung has devoted a lot of effort to improving the equipment and continuously expanding production capacity. In 2010, Samsungâ€™s sales occupied 27% of the global market. As a result, it has a strong bargaining power and requires all suppliers of raw materials to lower prices while ensuring quality. On this basis, Samsung has made product yields and pass rates high. The price is relatively low and it is very competitive.
Revaluation of business model Reporter: Is there any relationship between self-ignition of electric vehicles and the mode of charging or recharging? Zotye reported in the Development and Reform Commission's catalog is the battery of CNAC Lithium Battery. Will there be any mismatch in the use of universal batteries in Hangzhou?
Xie Zicong: The self-ignition of electric cars has nothing to do with the mode of charging or recharging. If the test report says that because the connector for the replacement of the battery is on fire, it can be considered as a problem of battery replacement. Hangzhou is obviously the problem of battery grouping. Not only that, the batteries that change batteries still have the time to take down and put them on a stable shelf for charging, which is better than bumping the car on the road for a long time. The latter's use environment and conditions are even worse.
According to the Western traditional business model, the standards of the relevant national departments are that the whole vehicle must be equipped with batteries in the sale of batteries. My point is that the relationship between the battery and the vehicle is the relationship between gasoline and the vehicle. The country can provide a standard. Based on this, it can promote the overall efficiency improvement, and should not require the vehicle company to match the battery of a certain brand. Report to directory. On the basis of this standard of the upper catalog developed by relevant departments, it is necessary to further develop and improve the entire business model, and the battery cannot be considered as an indispensable part of the vehicle.
Wang Binggang: There is a problem with this. I do not think that the battery of CNAC Lithium Battery is better than Vientiane. The latter's production equipment is still very advanced and quality control is still very strict. Before the Zhongtai battery box made by China National Aviation Lithium Battery, now is the use of universal battery box, then the battery box cooling requirements are the same, other battery fixed and vibration requirements are the same.
Strictly speaking, after replacing the batteries, the core part of the equivalent engine has changed. If you want to re-submit your application in accordance with the vehicle management measures, the purpose of re-declaration is to do more experiments.
Reporter: Now that the State Grid is pushing the power exchange mode, it will purchase batteries for assembly in Hangzhou. Is there any problem here?
Wang Binggang: The grid is also a battery box is also not certified, requires a strict certification system, the battery system has many safety issues need to rely on the vehicle system to control, and the vehicle can not be isolated, such as temperature control, not an independent The system needs to be designed together with the vehicle. My point is that the battery box is an important part of the car, not a separate part.
Xie Zicong: This is also a topic of debate. Now the State Grid must do several things: First, let everyone agree with your business model and technical plan; second, this is the strategic plan for building a network implementation; the third is to come up with a The rational distribution plan for state subsidies is that the subsidies are used to incubate the entire industry, rather than a company.
Reporter: China Southern Power Grid has also recently confirmed the business model based on electricity exchange. What do you think?
Wang Binggang: I do not advocate changing the mode. The battery is the core part of the car. In the electric vehicle design, the battery must be designed together with the car. It is not simply to put the battery in the car. The connection between the two is possible. Much. If you separate the design of the car and the battery and then simply assemble it, it will cause dislocations and some potential problems.
Now that the design of the battery pack is done by the power grid, the design of the entire vehicle is done by the auto manufacturer, so who will do the overall design. In addition, the quality of the products in the future will cause quality problems. If a problem arises in a conventional car, it is necessary to find a complete car factory. However, in order to adopt a replacement mode, the entire car factory provides bare cars and should not assume the responsibility of the battery.
This is a difficult problem to solve in the exchange mode. Even if these problems are solved, the power exchange mode may only be suitable for public vehicles. The personal car is a personalized thing, designed as a standardized car and battery, and the consumer's acceptance level. It is also a problem.
Xie Zicong: There is a misunderstanding about the current debate on charging and swapping. The entire vehicle company is represented by charging, the South China Net. State-owned power exchange, supplemented by charging, but did not say not to engage in charging, this is also given to the whole The depot has a choice to let the market decide which one to sell well. However, the main mode of power exchange is particularly important in the early stage of the development of electric vehicles. The current problem is that the business model of the State Grid and South China Network is determined, but the technical scheme is not mature, and it has not been recognized by vehicle manufacturers and battery factories. The cooperation of the people is also a problem. At present, it is still going it alone.
Take Hangzhou's power exchange mode as an example. The self-igniting Zhongtai electric vehicle is the mode of changing the power of the trunk. This model does not agree with the whole vehicle because the design of the vehicle has its laws and science, and the trunk is changed for electricity. The design puts the battery and the occupants in a space. If the battery is placed on the chassis and there is a metal partition, many problems will be solved. Moreover, all the demonstration vehicles are now modified, and are not independently designed according to the laws and scientific elements of electric vehicles. However, there are already several companies that have begun to make attempts. This requires the State Grid, South Network, vehicle manufacturers, and experts to discuss the technology line locked by the State Grid and form a unified one.
The battery industry needs an access system Reporter: Self-ignition is a frequent occurrence. Some people think that the trial operation of electric vehicles should be temporarily suspended.
Xie Zicong: I don't think it was a stoppage problem, but the trial operation was not effectively organized. Now the electric vehicle central enterprise alliance is all about it, the whole vehicle is dried, the battery is dry, and the energy supply is used for energy supply. Can not form a synergy. The development of new industries requires the integration of systems. The announcement issued by the Ministry of Science and Technology mentioned that the gap was broken. The Ministry of Industry and Information Technology is also discussing this issue. I think it is a great progress. Therefore, it should not be halted, but should be calmed down in advance. Together, a high degree of understanding of the laws of innovation in this industry, we must do a solid job.
Wang Binggang: We still need to do more in-depth research and development of electric vehicles, and invest more. At present, there are the same problems as high-speed rail. We are eager to achieve success in electric vehicles, and the pursuit of speed has not paid enough attention to the quality of industrial development. At present, local governments and certain departments are pursuing speed, and electric vehicles still have to be practical. Anxious moods can be understood, but after quality is achieved, they can be faster, but the speed is not satisfactory.
Reporter: During the trial operation of electric vehicles, there have been so many spontaneous combustion phenomena. How to regulate and avoid them? Is there a phenomenon that is driven by commercial interests?
Wang Binggang: The car has access to the system, but the battery is not. Only before the battery is loaded, the sample needs to be tested in the laboratories set up by several countries. As for what the factory is and what the product is, it is not like the car. Very strict access review. At present, there are 200-300 battery factories across the country. Some people have a little capital. Digging some people from the battery factory will start to produce batteries. Others claim to be inventors and they have also invested to build battery factories. The state needs to strengthen the management, certification, auditing, and access management of automobile power battery plants.
Xie Zicong: Commercial interests drove this incident but it was secondary. Since the "cakes" have not been made, how can the interests come from? The country has introduced a subsidy policy and has the electric cars been sold? Now I think the benefits are useless.
Our country has never organized a system of innovative work. We have not thought so. There is no such experience. Through this incident, China has quietly entered a new era. From the past of learning to the beginning of a completely new era of independent innovation, the Chinese can not simply reproduce, there is no reproducible thing, no teacher and no reference material. We must innovate and develop new industries, and this industry is of great significance.
Dong Ming: Samsung is the leader of the lithium power industry from weaker companies and relies on long-term hard work. This is also a lack of Chinese companies. Everyone does not want to work hard to accumulate. Without accumulation, it will only be eliminated.
The government's promotion of the market is indeed in its role, but everyone is very impatient and impetuous. Many companies cut corners in order to fight price wars, and the development of the lithium battery industry is still a relatively chaotic stage. What is certain is that companies that practice internal strength must be able to slow down. Slowly growing, the industry is facing a reshuffle. However, what is more dangerous is that foreign companies are now aggressive. If South Koreans, Japanese, and Germans enter our market, they have many years of technological accumulation and lower cost competitive advantages. This is for Chinese battery companies. It is the most dangerous.
Electric Grinder, Coffee Grinder
Jiangmen Taifai Technology Co.,Ltd , https://www.glaremecn.com