With the implementation of national energy saving and emission reduction policies, new energy vehicles are becoming more and more popular, and at the same time, charging piles need to accelerate the construction. Based on the current situation of charging pile construction, we focus on analysing the main problems existing in the development of charging infrastructure, and put forward corresponding countermeasures.
Introduction
In January 2022, China's Development and Reform Commission and other departments jointly issued "on further enhancing the implementation of electric vehicle charging infrastructure service guarantee capacity" that China's charging infrastructure to achieve the leapfrog development, charging technology, charging technology to rapidly improve the standard system gradually complete, the industry ecological steadily formed, has been built in the world's largest number of the largest area of radiation, the most complete charging infrastructure system of service vehicles. However, there are still residential communities to build piles difficult, uneven development of public charging facilities, the user charging experience needs to be improved, the industry quality and safety supervision system needs to be perfected and other outstanding issues, there is an urgent need to accelerate the relevant technology, mode and mechanism innovation, and further enhance the charging service guarantee capacity.
Development status of new energy vehicle charging pile at home and abroad
Domestic situation
In the policy support and scientific and technological progress drive, China's new energy automobile industry continues to grow, vigorously develop new energy vehicles actively respond to the national green travel, energy saving and emission reduction policy, to a certain extent, reduce China's dependence on petroleum, contributing to China's sustainable development. 2015, China's new energy vehicles for many years in the world's first sales and retention, although the new energy vehicle development rate is significant, but the charging pile of new energy vehicles is relatively insufficient. Although the development speed of new energy vehicles is remarkable, but the charging pile of new energy vehicles is relatively insufficient. According to statistics, as of June 2020, the new energy vehicle market ownership of 4.17 million vehicles, while the new energy vehicle charging pile is 1.322 million units, the car pile ratio of 3.2:1. This shows that the number of charging piles less than 1/3 of the number of new energy vehicles, the shortage of charging piles limits the development of the new energy vehicle industry. The state has repeatedly issued measures to promote the construction of charging infrastructure, which has largely promoted the development of charging infrastructure for new energy vehicles. 2020 April, the National Development and Reform Commission will be new energy vehicle charging piles as one of the seven key areas of "new infrastructure". Localities have introduced corresponding policies to enhance consumer confidence, making more consumers willing to buy new energy vehicles. It is expected that by 2035, pure electric vehicles will dominate the auto sales market.
Foreign Dynamics
Relevant data statistics, in 2019, the global new energy vehicle public charging pile compared to 2018 growth of 60%, visible charging pile development is very rapid. In recent years, many countries are committed to the construction of charging infrastructure, for example, the U.S. government has been focusing on the research of new energy vehicle charging technology, and proposed to set new standards for electric vehicle charging network. As of August 2019, the U.S. charging facilities have basically covered the whole country, it has built 25,843 charging stations, charging piles 76,954; the United Kingdom is also promoting the construction of charging infrastructure, according to the UK Department for Transport statistics, a charging service provider to build electric vehicle charging stations has accumulated more than 270,000 units. And the United Kingdom to encourage more convenient charging payment methods, promote the implementation of contactless payment and other functions; Japan attaches great importance to the development of new energy vehicles and charging pile construction, and vigorously publicise and promote the application of charging piles. According to statistics, the total number of charging piles constructed is more than 50,000, of which public charging piles occupy a dominant position, and most of the public charging piles are not constructed for the purpose of making profit, and the funds for the maintenance and construction of the later stage mainly rely on the government subsidies and funding from the car companies.
Problems in the construction of charging piles
Low utilisation rate of charging piles
As of June 2022, the domestic new energy vehicle pile ratio of about 2.555:1. The reasons:
① land resources are limited, charging piles established in towns and cities rather than the establishment of remote areas of high cost, some operators in order to get the number of piles related to the construction of subsidies, some of the piles will be installed in remote areas;
② charging pile supervision and maintenance efforts to be improved, some fuel vehicle owners accounted for the charging pile parking space. The charging station is not yet in good condition. According to the results of the survey, more than 35% of users have encountered difficulties in finding charging piles, more than 20% of users encountered in the use of public electric vehicle charging piles failures but repair problems in a timely manner, 28.3% of users have encountered car parking spaces occupied by fuel vehicles;
③ lack of sharing concept, some 4S shop charging piles only for their own brand of new energy vehicles charging services, and most of the private charging piles for personal use only, and most of the private charging piles are for personal use. Most of the private charging piles are for personal use only, with long idle time and low utilisation rate.
Poor interface compatibility of charging piles
The charging application of new energy vehicles is very complex, which is reflected in the different models, application scenarios, charging piles of various types and other characteristics. Various new energy vehicle enterprises in the charging problem "their own way", reciprocity and interoperability is not strong, resulting in the construction of charging piles there is exclusivity, and charging piles of international standards still need to be improved. 2015 national standards due to the introduction of the project is not in the mandatory authentication, and modify some of the contacts and mechanical lock size, although the old and new charging piles are compatible, but some of the domestic charging operators are compatible with the new charging piles, but the charging piles are not compatible with the new charging piles, but the charging piles are compatible with the new charging piles. Although it is mentioned that the new and old charging piles are compatible, some domestic charging operators have not reformed the old charging piles according to the new national standard, resulting in the incompatibility between the old models and the new national standard charging piles. Due to the different vehicle models and their own design problems, even if the vehicle plug and socket size can meet the requirements, but there may be unable to charge the situation.
Part of the charging pile facilities are old, there is a risk of spontaneous combustion.
The quality and standard of charging piles in China is non-compulsory, so the fire safety and other standards are not unified for the time being. The technical level and supervision of each operator are different, resulting in some charging piles with certain safety hazards. In order to save time, charging piles generally use high-power, high-voltage mode of operation, but many electric vehicle batteries are difficult to withstand ultra-high-power charging, resulting in charging piles of smoke fire, leakage risk increases.
At present, the charging pile low price competition compressed the operator's profit space, profitability is not enough to lead to the station negligent management, the lack of corresponding monitoring platform and network operation and maintenance team, equipment old no one maintenance, from time to time charging pile spontaneous combustion phenomenon. 2020 September, Shanghai Municipal Market Supervision Administration released data show that only in August that year, the domestic occurrence of 15 new energy vehicle smoke and fire accident. In August 2019, Guangdong Product Quality Supervision and Inspection Research Institute published a risk test report showing that 70% of the charging pile products produced by 9 enterprises included in the risk test do not comply with the national standard. According to the new energy vehicle national big data alliance disclosure, new energy vehicles in charging and fully charged static state is prone to spontaneous combustion accidents, accounting for 38% and 24%, respectively, especially the battery state of charge (SOC) more than 90%, the number of spontaneous combustion accidents accounted for 45% of the total spontaneous combustion accidents.
In addition, some charging piles are located in humid environments, and if the sealing of the charging pile is poor, it may cause leakage of electricity, causing damage to the parts of the new energy vehicle being charged. When charging, it is necessary to ensure that the car interface and charging pile plug connection is stable, if the interface is not firmly inserted, it is very easy to lead to leakage of electricity or produce electric spark phenomenon.
Suggestions for countermeasures
Implement and optimise incentive policies
Optimise the investment and construction operation mode of new energy vehicle charging piles, gradually increase the coverage rate of charging piles in various districts and shopping malls, and accelerate the construction of charging piles in non-commercial areas and suburbs. For the urban public charging network, comprehensive consideration should be given to a reasonable layout; for the charging network in counties and towns, charging piles should be optimised in terms of regional distribution, and publicity for new energy vehicles should be increased; for highway charging piles and filling stations, DC charging and power exchange should be the main focus to improve the efficiency of road access. Optimise charging services for new energy vehicles, encourage regions to introduce charging infrastructure construction subsidies and operating subsidy policy, increase the public charging pile operating subsidies. For example, in the suburbs and old districts to set up shared charging piles, idle resources open to the outside world, through the sharing of charging to meet the requirements of car owners, can greatly enhance the utilisation rate of private piles, private piles for the owner to bring revenue at the same time, but also save charging costs. The new community should do a high standard to reserve space for the construction of charging piles, if the number of charging piles in the community can not meet the actual needs of the owners, you can consider the establishment of road charging piles.
Design related insurance products
The spontaneous combustion of new energy vehicles is fast and violent, and the consequences of spontaneous combustion are serious. Spontaneous combustion and other risky events have become the focus of many car owners' concern, and should be included in the scope of coverage. 2021 December, the China Insurance Association issued relevant provisions, charging into the "vehicle use process" scope. It is suggested that in the next stage of the programme, the cost of claims can be reduced for more refined pricing, covering the definition of insurance liability for new business models such as the power exchange model, which is not mentioned in the example clause, and including the risk of Internet of Things (IoT) technology and the risk of fuel-cell vehicles in the scope of coverage. It is recommended that insurance companies provide comprehensive risk protection products for vehicle damage, household circuit damage, third-party property damage and casualties caused by the use of private charging piles in the course of the use of private charging piles, and develop in the direction of refinement, specialisation and exclusivity.
Insurance products can also focus on the following types:
① charging pile exclusive quality insurance;
② for the public charging pile, to mitigate public property damage and casualty losses, matching the reasonable charging field public liability insurance;
③ due to the maintenance and use of private charging piles in the process of a certain degree of irregularity, but also for the individual to provide a comprehensive risk protection products.
Establishment of reputation management mechanism
Charging infrastructure can also be combined with blockchain technology to implement reputation management mechanism. New energy vehicle users can evaluate the charging pile from the safety coefficient, convenience, charging time, etc. The evaluation directly affects the reputation value of the charging pile, the higher the reputation value, proving that the charging pile's convenience and safety are higher, and the probability of other electric vehicle users using it will be greater. It is recommended to establish a national unified platform, including all charging piles in the country, and use big data technology, combined with the reputation value, fast and slow charging and distance to the user intelligent recommendation of charging piles, but also to join the Internet of Things technology, remote control, and share big data to the electric power sector, automobile manufacturers and charging pile operators, etc., to improve the resource utilisation rate.
Vigorously promote technological innovation
It is recommended that local governments introduce policies for the introduction of high-end technical talents, increase support for scientific research and innovation, promote technological innovation in charging infrastructure, enhance high-tech support and guarantee and market service capacity, and formulate a unified 3-year special action schedule for fast-charging facilities, specifying the construction scale, land use planning, charging capacity, and other key objectives. For the low charging efficiency, it is recommended to develop high-power DC fast-charging charging piles, clarify the fast-charging charging pile planning methods, and strengthen the construction and operation of intelligent charging piles. With China's "double carbon" goal, photovoltaic charging pile and new energy vehicles can effectively enhance the proportion of renewable energy applications, better achieve the low-carbon goals, you can explore the photovoltaic charging pile and other new kinetic energy.
New energy vehicle charging pile development direction
Shared Charging
Shared charging is a concept that enterprises or individuals build to meet the charging of electric vehicles, and can provide charging services to other vehicles. At present, many sharing charging platforms continue to develop, and sharing charging is becoming more and more convenient. New energy vehicle users can register their personal charging pile information, based on the charging price of nearby charging piles and the charging time required to query. In the operation and management, the power supply company regularly sends professional maintenance personnel to overhaul the charging piles, real-time inspection of the charging pile power supply and operation status, so that the charging pile can better provide services for new energy vehicle users. Shared charging pile mode refers to the sharing of charging space and charging time, which can effectively integrate idle resources, improve the utilisation rate of charging piles and meet the charging needs of new energy vehicle owners. On the one hand, the platform and the car pile owner can make certain economic benefits under the sharing mode to achieve the purpose of profitability; on the other hand, the charging pile can charge and discharge in both directions and transmit electricity to the power grid, which can adjust the electric load, improve the quality of electric power, and consume the role of renewable energy.
Wireless charging
Wireless charging technology originates from wireless energy transmission technology, is an emerging charging technology, the use of alternating electromagnetic field electromagnetic induction (CT induction) to achieve wireless transmission of energy. Wireless charging can be realised by electric field coupling, electromagnetic induction, magnetic field resonance and radio wave, each of which has its own advantages and disadvantages, among which the electromagnetic induction wireless charging technology has been basically commercialised and engineered, and its basic principle is that the current passes through the primary coil, and due to the electromagnetic induction effect, it generates an induced electromotive force on the secondary coil, and then transmits the current to the new energy vehicle. The biggest advantage of wireless charging is that it does not need to be equipped with charging cables and charging interfaces, which can effectively solve the problem of incompatible charging interfaces resulting in the inability to charge. Wireless charging can also be buried in the ground coil. There is no exposed connector, saving space on the ground, to a certain extent, to avoid charging leakage, electric shock and other safety hazards. Even in the rain and snow and other adverse weather conditions, they can ensure the safety of the charging process.
Power exchange technology
Power exchange mode can effectively achieve rapid range, and the operation is very simple, that is, the energy depletion of the battery is replaced by a new power battery, so as to realise the "second charging". At present, the main forms of power exchange are vertical plug-in power exchange, parallel plug-in power exchange and end face power exchange. Pair-plug power exchange has a higher degree of automation, so it is widely used. In addition to the advantages of power conversion technology, short replenishment time, but also has the safety, enterprises can grasp the real-time battery status, timely replacement of damaged batteries, reduce the occurrence of safety accidents. Power conversion technology can also improve the battery recycling system, the end-of-life battery pack laddering and recycling to extract raw materials, end-of-life batteries can be disassembled and reorganised for reuse in the field of energy storage, but also for the loss of serious end-of-life batteries, cobalt, nickel, lithium, and other precious metals through the chemical way of refining for re-use. Encourage the exchange of electricity to ease the pressure on the power grid, charging at night during the low peak period of electricity consumption, discharging during the daytime peak period of electricity consumption, shaving peaks and filling valleys, with photovoltaic, wind power generation, the establishment of a distributed energy storage system, to achieve a better operation of the power grid while improving economic efficiency.
Conclusion
Improving the charging infrastructure is conducive to the low-carbon travel of new energy vehicle users, and the increase in new energy vehicle ownership is important for promoting the development of green economy and the high-quality development of new energy vehicle industry. Therefore, in view of the outstanding problems in the development of charging infrastructure, we should further strengthen the top-level design, support the merger and reorganisation of advantageous automobile enterprises, implement the reputation management mechanism, establish and improve the industry regulatory system, encourage the promotion and application of relevant safety liability insurance, and strengthen the research and development of new technologies, and explore the sharing of new modes of charging, wireless charging, and power switching modes.