With the continuous improvement of battery and management systems, the driving range of electric vehicles has been able to basically meet the daily commuting needs, and the electric vehicle market has entered a new stage of rapid growth. However, unexpectedly, with the significant increase in the ownership of electric vehicles, many car owners once again faced the problem of slow charging speed and inconvenience caused by the use of cars during the "Eleventh" long holiday this year. As one of the means to solve this pain point, car companies further promote the layout of fast charging technology and expand the scope of popularization and promotion of fast charging stations.
However, while this trend is gradually emerging, there are still some problems to be solved in fast charging technology, such as how to avoid the damage of fast charging to the battery? Whether the fast charging station needs to be built on a large scale, and what scenarios are applicable. In this regard, Liu Kai, director of the Technology and Certification Department of the China Electric Vehicle Charging Infrastructure Promotion Alliance, said in an interview with China Automobile News a few days ago that charging efficiency will become an important consideration for the construction and operation of charging facilities in the next stage, but considering factors such as charging standards and unclear technical paths, fast charging also needs to comprehensively balance related elements and gradually promote.
Electric cars are lined up to charge
The problem of replenishment is prominent
"Eleven" small long holiday, the problem of electric vehicle charging difficulties rushed to the hot search. There is an electric vehicle owner who returned to Hunan from Shenzhen, Guangdong Province, who said on the Internet that when he charged the electric vehicle in the Service Area of Hunan Leiyang, he spent more than 5 hours, and it originally only took 8 hours to get home, which took 16 hours, and a lot of time was spent waiting in line. What is even worse is that because of the fear of being cut in line, many electric vehicle owners can only stay by the car the whole time, and even dare not go to the bathroom, and even in some places, there are electric vehicle owners competing for charging piles. This is not an isolated case, the State Grid smart car networking platform highway charging heat map shows that in the National Day holiday, a total of 409 charging stations have queued up, accounting for 18% of all highway stations, compared with the 2020 National Day holiday, the number increased by 60%, almost every 5 high-speed charging stations have one in the queue.
The main reason is that the number of charging piles is relatively insufficient. According to statistics, as of September 2021, the cumulative number of charging infrastructure in the country is 2.22 million units (roots), an increase of 56.8% year-on-year. However, the growth rate of charging infrastructure is far less than the increase in domestic electric vehicle ownership. According to the latest statistics released by the Ministry of Public Security on September 12, as of September this year, the number of pure electric vehicles in China reached 5.52 million, and the vehicle-to-pile ratio was about 2.5:1. If some old, damaged and long-term idle charging piles are excluded, coupled with the fact that many electric vehicle owners choose to travel by car during the "Eleventh" long holiday, the demand for public charging piles surges, and it is inevitable that there will be insufficient charging piles.
In addition to the lack of charging facilities, there is another reason why car owners queue up to charge is that the charging time is too long. 1 ordinary fuel car can basically complete the refueling in about 3 minutes, but the mainstream electric vehicles on the market at present need to be fully charged, almost all need to spend more than 1 hour of time, even if some of the more advanced electric vehicles, the power from 30% to 80% at least takes about 30 minutes, not to mention that there are many car owners insist on charging to more than 90%, but in fact, the trickle charging time in the late charging period will be greatly increased, and naturally cannot achieve the purpose of rapid replenishment. It further extends the time for the rear car to queue up for charging.
Based on this, Ouyang Minggao, an academician of the Chinese Academy of Sciences, proposed at a seminar organized by the Electric Vehicle Hundred Recently that to solve the worries of charging, greater power fast charging technology is needed, and super fast charging is the trend of the times.
Car companies, battery companies
Plus layout
In addition to improving the user charging experience, fast charging piles can also improve the utilization rate of charging piles by shortening the charging time, which has been valued by car companies, pile companies and battery companies in recent years.
In terms of products, car companies have released new products or platforms equipped with fast charging technology: a few days ago, at the 2021 Dongfeng Motor brand autumn conference, Lantu Automobile released its self-developed 800V high-voltage platform and super fast charging technology, and announced that the technology has entered the vehicle testing stage, which is expected to become the earliest high-end electric brand in China to mass-produce 800V high-voltage super fast charging technology. Coincidentally, on September 8, BYD released the e-platform 3.0, charging 5 minutes, the maximum driving range of up to 150 kilometers; and the earlier listed GAC AION V Plus also announced that it was equipped with AION super-double battery technology for the first time, and at the same time took the lead in supporting the A480 super charging pile, which can achieve the effect of charging 5 minutes and driving 207 kilometers in the future.
In addition to releasing products, car companies are also actively accelerating the pace of fast-charging pile construction. In April this year, ARCFOX Jihu brand first exclusive supercharging station in Beijing South Third Ring Road Songjiazhuang Pomegranate Center put into trial operation, the first supercharge station equipped with 12 supercharging piles, single pile maximum charging power of 180kW, according to reports, the end of the year delivery of the Polar Fox Alpha S HI version can reach a charging 10 minutes, the maximum continuous driving speed of 197 kilometers; in August this year, Xiaopeng Automobile announced that the first batch of 11 high-speed supercharging stations have been completed and put into operation in July, and have now realized the Shandong section of the Beijing-Shanghai Expressway. The Henan section of the Beijing-Hong Kong-Macao Expressway runs through, and each station is laid out with two supercharging stations exclusive to the owners of Xiaopeng, with a charging power of 180kW. The follow-up Xiaopeng supercharge will also continue to run through Beijing-Shanghai, Beijing-Guangzhou, Beijing-Hong Kong-Macao and other high-speed routes; on September 28, the supercharging station under the extreme krypton energy brand "Extreme Energy" began to operate, and the ultra-long endurance single motor WE version model can reach 5 minutes of charging, and the NEDC continues to increase by 120 kilometers.
Fast charging does not have the conditions for large-scale promotion
Standards and technologies remain bottlenecks
On the surface, fast charging is currently one of the "shortcuts" that can solve the user's charging inconvenience, but in fact, in addition to special periods such as the National Day holiday, most electric vehicle users' demand for fast charging is not so urgent. Industry experts pointed out that considering that the use scenarios of the fast charging mode are generally mostly operating vehicles, the emergency recharge of private cars may only account for a small part, so from the perspective of market demand, fast charging will remain only a small branch of the charging application scenario for a long time in the future, rather than the mainstream trend. Therefore, in the charging scenario of highways and urban and rural public charging stations, fast charging should be the mainstay, and the charging power should be set in combination with the actual application needs of the vehicle, and do not blindly greed for speed.
The issue of construction costs cannot be ignored either. "In order to meet the charging needs of more users, the number of fast charging piles will inevitably show an increasing trend, but it is certainly necessary to consider economic benefits." A person in charge of a charging pile operation company admitted in an interview with the media that the average market price of a 180kW fast charging pile is 50,000 to 70,000 yuan, plus the site and power grid and other supporting facilities, the cost is not low, but in addition to the National Day, May Day, usually idle.
Everbright Securities has calculated the return cycle of 60kW DC fast charging piles, calculated according to the cost of a single pile of 60,000 yuan, assuming that the charging service fee is charged 0.6 yuan / kW, the single pile utilization rate is 5%, that is, 1.2 hours per day, and the investment recovery period takes 3.8 years. If other costs such as operations, land and construction are added, this period will be extended even longer.
Another problem that hinders the rapid popularization of fast charging technology is that the technical route is not uniform, and the industry urgently needs to revise relevant standards. According to Liu Kai, because the 2015 version of the national standard has restrictions on achieving faster charging speed, the current fast charging technology mainly takes two implementation paths: one is led by car companies, upgraded on the basis of the 2015 version of the national standard, and can be compatible with the 2015 version of the national standard charging facilities; the other is the super charging system led by the relevant standard organization and some charging facility operators and manufacturers, because it is not directly compatible with the existing 2015 version of the standard, it needs to be equipped with a adapter.
"The two routes are quite different, and at the same time will have a greater impact on electric vehicle users, so the industry must determine as soon as possible which scheme to base on to form a fast charging standard." Liu Kai suggested that since most of the existing and newly added electric vehicles will still use the 2015 version of the national standard fast charging standard, it is better to upgrade the 2015 version of the national standard.
Third, in order to achieve the rapid development of super fast charging, the supporting battery technology must also follow. Liu Kai told reporters that because high-power fast charging has a greater impact on the life and safety of power batteries, it is necessary to optimize the battery material, cell structure, battery management system, charging strategy and other systematic optimization to prevent the risk of thermal runaway of the battery and the rapid attenuation of cycle life, so the difficulty of achieving high-power fast charging is how to prevent thermal runaway on the one hand and take more protective measures, on the other hand, to minimize the resulting decline in energy density of the battery system and the rise in cost. Based on this, how to greatly increase the charging power at the same time, to ensure that the power battery life cycle of the attenuation in line with the relevant requirements, will greatly ensure the safety of charging, has become the current power battery enterprises and automobile companies are carrying out technology research and development and research and development of important topics.
Text: Shi Yunyun Editor: Chen Wei Layout: Li Peiyang