Why unsatisfactory electric vehicle charging
In June, the state-subsidized electric cars get strong policies to promote the pilot, the charging station construction, "Running" also opened on schedule, attracted more attention to the parties.
"Battery safety worries, the standard uniform of the storm, the emergency home charging, when these have become a barometer of quality and safety impact of electric vehicle charging station when the main factors, to solve these basic quality issues, has become a priority charging station construction . "In an interview with reporters, senior Department of Automotive Engineering, Tsinghua University Lu Languang expressed such concerns.
Battery safety worries
"Charging station construction is the biggest security risks the battery quality and safety." Lu Languang told reporters that this is a worldwide problem, even for international auto giants such as General Motors, Toyota, also has been the trouble.
Remark Bumiu. Recently, Honda Motor president, said Takanobu Ito, battery life is too short mileage, performance, easy to weaken, restricting the construction of electric car and charging station the main reason. Press Association in Detroit at an event, world-renowned consultancy Boston Consulting Group also pointed out that "charging station and electric car battery production is limited by cost and technical level."
So, where are aspects of the product, but off the battery? Why it will become a drag on the charging station "legs"?
"The key is the reliability of the battery bad." Guangzhou, Huizhou deep electronics company boss Hutai Guo explained that, at present, the widespread use of battery electric vehicles by the hundreds or even thousands of volumes, capacity of the same size lithium batteries assembled together . In theory, the standardization of production processes in the environment, "baked" in each cell, security and reliability should be the same, but the battery technology itself, there is a gap, coupled with installation personnel, technology, equipment and other objective factors , resulting in different reliability of each battery, so the fast charge process, each cell "saturation" with, the decay rate are not the same, resulting in cell block there consistency bias and other issues, giving the charging station a security risk.
If the above is only limited to theoretical analysis, then, some of the actual process of charging the battery explosion, even when those who caused the attention of the construction of charging stations. Lu Languang reminder, compared with an individual or cell phone charger, charging station in the event of safety problems, the damage will be greater, therefore, who must understand the construction of upstream products - batteries that special "oil" the quality problem, comprehensive consideration of the charging station with the matching problems. For example, the charging station to provide the main services - fast charging, there are three aspects to security risks.
First, the use of departure from the designed. Battery generally by "slow charge or a few dozen hours" as the best use of design, and charging stations generally provide a "fast-charge ten minutes or even minutes' time to meet user needs; Secondly, charging stations poor match with the battery. A variety of cross-charging station, DC varies, current sizes, fast-charge in the force, not only will reduce the battery life, and may lead to a variety of quality accidents; third, from a technical perspective, the current electric is the most automobile use lithium batteries. Lithium is also active than sodium metal element of the fast-charge lithium is too easy to make active, so that the battery electrolyte precipitation, bubble phenomenon, which is usually the people who have seen the battery easy to convex from the "packet", and feel a touch of fever, a serious cause battery explosion and other accidents.
At present, the nickel-metal hydride batteries to replace the lithium battery series the ideal energy. But Hu Taiguo that although security is better than nickel-metal hydride lithium battery, but the energy stored in the same state, and its volume 1.5 times larger than the lithium batteries, lithium battery device in the current account for vehicle size, weight and 1 / 3 of , obviously contrary to the current general direction of the global appeal of the thin battery. From the current situation, and now the mainstream nickel metal hydride battery business to major OEMs in the trial, the commercialization of five years is unlikely, therefore, in the next 3 to 5 years time, or should be based on the lithium battery charging station building to enhance the quality and safety precautions.
The standard uniform of the storm
If the battery problem is the advent of electric vehicle charging station construction has been restricted worldwide problem, then, for China's current herd of charging station construction project, the first solution or uniform standards.
Dragon Motor Co., Ltd. Shenzhen Wuzhou as electric vehicle research and development center director, Deng Xianquan experiences: in the streets of Shenzhen, sporadic electric car charging stations both Southern Power Grid, National Grid investment in equipment, as well as electric car companies such as Shakespeare Di, Continental Long distribution of charging stations, in addition to a wide variety of styles, the electric car because the service object varies, which is uncompromising standards for power plants, such as the charging socket on the interface there is a clear difference.
Worked in the Nanjing Automobile Group, Chery Automobile of China's passenger car market information and then co-Shun Yang, Vice Secretary-General to provide the data showed that China has more than 80% of the provinces started charging station construction project. At the national "energy-saving and new energy vehicle demonstration and application of recommended models directory", the list of new domestic energy more than 100 automotive products, which claim to obtain a pure electric car technology vehicle company of 40 or more, the number is far far more than Japan and the United States. Affected, especially the government subsidies for private pilot car, setting off a new round of charging station construction boom: the power grid companies have introduced Jianzhan planning; the three oil giants began distribution; local governments jointly pushing local businesses, "acting "; private enterprise to try it.
It is because of the involvement of the main building are more technical route is not uniform, resulting in differences in specific criteria. Therefore, "a large number of non-compliant charging facilities, not only result in waste of resources, and hidden safety problems." Smart Grid National Grid Energy Research Institute Zhang Yibin even fear, in the absence of unified and standardized under the guidance of technical standards, subsidies to the private car incentives may also be short-lived only a large number of charging stations "freaks."
"Universal electric car, the first uniform standards for charging stations, including the uniform amount of current payment methods, measurement standards, a variety of models such as hybrid or pure electric vehicles such as the interface specifications." Chery Automobile in Beijing West Fourth Ring Road store, the former to the manager of a company car Guang-Ming Xu hopes that future standards will allow the introduction of electric vehicles wherever they go, can be easily added to electricity.
Charge limited family
Huawei Qiao, who lives near the East Third Ring Road Beijing, Mr. Zhang bought a hybrid last year, but the trouble is that every time the total charge to drive to 10 km away from its own underground garage to charge a friend's house. "Because the cable is too thin at home, can not meet the charging current when the load requirements." Zhang is very distressed.
Lu Languang said, according to the relevant national standards, at present, the Chinese family is generally the amount of current electricity standard is 3 to 6 kW / hour, maximum of 8 new residential kW / h, electric vehicles are now fundamental to 20 kilowatts of energy savings When power, the exercise of calculating mileage 150 km, slow charge batteries are 3 to 8 hours. If the fast charge time, current load is too large, may cause short-circuit power, wires on fire, and dangerous. In addition, each residential electricity supply is limited, with the popularity of electric vehicles, electricity use increases, this potential risk of increasing. Therefore, how to solve the family charge, has become a popular electric car one of the key factors.
In addition, a block 100% of stored energy, providing 150 km mileage of electric vehicle battery length of 100 cm, width 70 cm, 15 cm high, about the same size from the 100's lithium battery components. Such a large piece of the battery, as difficult as the bike to the home battery charging. For no special cables, no garage, and they live in high-level private car owners, car continued to be clearly a problem.
According to the Ministry announced on May 26 this year, "the automobile industry the direction of technological progress and investment in technological upgrading (2010)" provides that electric cars charged time in about 7 hours, fast charge to 80% charge time and a half hours so, in order to meet the electric vehicle 80 kilometers per hour maximum speed, 100 km driving range needs. There is no doubt, in terms of technology, or from the policy requirements, the "slow charge" is to give electric cars the ideal complement to, rather the development of safe, reliable, portable home charging station is the ideal "slow charge" plus power station.
"It should say, in the full flowering of the charging station to get into the limelight in the future, who seize the opportunities for home charging station, who will be able to get the market because the current government subsidy is for the private car owners." But Hu Taiguo also predicted: "The real popularity may take 10 years or so."