Xinhua News Agency, Guangzhou, April 27th Question: Frequent accidents, can new energy vehicles be safely driven?
Xinhua news agency reporter
From the "roof protection" in Shanghai to the post-accident burning in Guangzhou and other places, recent cases of brake failure and spontaneous combustion have pushed new energy vehicles to the forefront. On the one hand, various capitals have rushed into the new energy automobile industry, and on the other hand, frequent accidents have caused public concern. How to treat safety accidents in the process of rapid development? Where is the key to battery safety? Can new energy vehicles be driven with peace of mind? Xinhua News Agency conducted an investigation.
Frequent accidents "step on the brakes" for the development of new energy vehicles
Recently, the rapid development of new energy vehicles has caused frequent accidents, including fire and combustion after the accident, spontaneous combustion caused by batteries, and brake failure.
On April 17, a Tesla in Zengcheng, Guangzhou, caught fire and burned, and one passenger died. The cause of the accident is still under investigation. On the same day, a Tesla car in Houston, USA, had an accident and caught fire and was burned.
On April 14th, a Xpeng Motors in Tianhe District of Guangzhou City spontaneously ignited while charging. The company said that the cause of the accident was under investigation.
The reason for the "brake failure" that caused the focus of public opinion is still unclear. After the "roof rights protection" incident at the Shanghai Auto Show, Tesla was exposed to many cases of brake failure in Hainan and other places. As an iconic enterprise of new energy vehicles, Tesla is facing a crisis of trust.
As a new thing, it is a fact that technology is immature. In fact, in order to gain the trust of consumers, new energy automobile enterprises need to pay more responsibility, and even need to be tested under a magnifying glass. However, some enterprises’ lack of honest behavior and inadequate services have aggravated public doubts.
At the end of last year, LI, who was deeply trapped in the "broken axle door", had to publish a letter of apology and announce the recall of the faulty car after trying to cover up the quality defect of the ball pin of the lower arm of the front suspension of his car with "hardware optimization and upgrade".
Tesla once aroused public anger because of his arrogant attitude. After the "roof rights protection" incident, Tesla accused the car owners involved of "contributing too much negative" and claimed that the company had tried its best to solve the problem, and the car owners’ demands were unreasonable and the company would never compromise. However, it was immediately revealed that it refused to provide complete driving data half an hour before the vehicle accident. The China Consumers Association said that the primary premise of business operation is to respect consumers, and enterprises with data should use professional knowledge to conduct strict self-examination, instead of turning technological advantages into obstacles to solving problems. After that, the companies involved provided data.
Many insiders said that according to the existing statistics, the fire accident rate of new energy vehicles is lower than that of traditional fuel vehicles. However, as a national strategic emerging industry and the direction of future transportation transformation and development, the public is highly concerned and sensitive about this, which psychologically magnifies the sense of insecurity. These accidents can, to a certain extent, cool down the "high fever" new energy automobile industry and make the industry develop more healthily.
Growing pains: high nickel risk under long battery life
Why is the battery "easy to destroy"? Wang Wei, chairman of Xinwangda Electronics Co., Ltd. believes that it is difficult to put out a large-capacity power battery after it catches fire and the risk of re-ignition is high, which is the pain point of the development of new energy vehicles.
Under the background of "mileage anxiety" and "endurance anxiety" in the industry, long endurance has become the number one task in the industry. At present, there are two main technical routes to solve this problem, namely ternary li-polymer and lithium iron phosphate battery.
As a widely used product, the main function of nickel in ternary li-polymer is to improve the energy density, that is, the unit storage capacity. In order to improve the cruising range, the proportion of nickel in the battery cathode material is getting higher and higher, and the ratio with cobalt and manganese is increased from 1:1:1 to 5:2:3, then to 6:2:2, and finally to 8:1:1.
Zhang Ming, general manager of Zhuhai Zhongli New Energy Technology Co., Ltd. said: "The thermal stability of high nickel ternary materials is poor. The higher the nickel content, the higher the energy density of the battery, but at the same time the higher the risk of thermal runaway of the battery. "
Respondents said that multi-path research and development of battery technology can be encouraged. After all, new energy vehicles are still a new track, whether it is ternary lithium batteries, lithium iron phosphate batteries or other batteries, as long as they meet the conditions of China’s resource endowment and safety standards, they can all be active.
"However, it is necessary to be alert to the unilateral pursuit of high energy density by power batteries, and to eliminate mileage anxiety on the surface. In fact, many technologies have not been fully verified and commercialized." Liang Rui, vice president of Xinwangda Electronics Co., Ltd. said.
Standards such as "Safety Requirements for Power Batteries for Electric Vehicles" issued in May last year require that the battery system will not catch fire or explode within 5 minutes after the thermal runaway of the battery monomer occurs, leaving escape time. Li Yunfei, general manager of BYD’s brand and public relations division, believes that five minutes is still insufficient in the face of the situation that the car door may be damaged and difficult to open after the accident. If it can reach half an hour, it will be more secure.
Fill the "blind spot" of system detection and eliminate potential risks
At present, there are about 5 million new energy vehicles in China, which will increase rapidly in the future. Power battery and system risks should not be underestimated.
The safety accident that happened in Zengcheng, Guangzhou on April 17th even led to the debate about Tesla AP function (automatic assisted driving) "grabbing the steering wheel". Some car owners broke the news one after another, saying that the automatic driving of existing new energy vehicles sometimes happens when they suddenly quit at the corner, which directly refers to the safety of the electronic control system.
Zhang Ming said that the fundamental difference from traditional fuel vehicles is that the electronic control system of new energy vehicles is a key link in operation. If there is no professional system testing organization and no automobile enterprise to provide corresponding driving data as support, only the hardware of new energy vehicles will be tested, and the result may be "no abnormality", which may actually hide risks.
People in the industry suggest that policy adaptability should be improved, and a standard system for testing and evaluation of new energy vehicles should be established. "Annual review" and daily maintenance should be included in the performance testing of power batteries. "The" Regulations on the Implementation of the Road Traffic Safety Law of the People’s Republic of China "requires that cars must be inspected annually, but the current testing indicators are all aimed at traditional fuel vehicles." Zhang Ming said that there is no specific "annual inspection" standard for new energy vehicles such as pure electric vehicles, and it is necessary to formulate standards for passing the annual inspection and the entry threshold for the annual inspection units.
"Pure electric new energy vehicles can only detect systems such as appearance, chassis, lighting and braking at the inspection station. However, key power battery packs and other components cannot be disassembled, which involves issues such as responsibility attribution and technical confidentiality of enterprises. " Zhang Ming said.
At present, intelligent networked cars are changing from vehicles to mobile intelligent terminals, energy storage units and digital spaces. There are hundreds of sensors on a car, which produces a huge amount of car data, user data, road network data and so on. How to store data, transmit data and use data has become a major issue that regulators, vehicle manufacturers and data companies must face.
"Data is becoming the core secret of intelligent networked vehicles, and it is impossible for enterprises to provide all data to the regulatory authorities. But if the data of the regulatory authorities are not mastered, how can we supervise them? How to support the testing ability of public testing institutions? " Hu Yixiang, vice president of Guangdong Guanghua Technology Co., Ltd. said. (Reporter Zhou Qiang, Wu Tao, Sun Fei, Yin Peng, Li Jiale)