Recently, Volvo officially said that it was working with its partners to test the wireless charging function of vehicles in the urban use environment. "Trying exciting new technologies in a real environment and testing new charging technologies with selected partners is a good way to evaluate our future alternative charging solutions for cars," said Mats Moberg, head of research and development at Volvo Cars.

In fact, many car companies have targeted the wireless charging car market. For example, Zhiji L7, which supports the 11kW wireless charging function, will be launched at the end of March. BMW has previously equipped a 3.2kW wireless charging system for the 530e iPerformance model. In addition, domestic and foreign mainstream automobile enterprises have started the research and development and layout of wireless charging technology, and electric vehicle charging piles have formed a relatively clear mass production plan.

Compared with the existing charging and changing technology, what is the difficulty of wireless car charging? Will new energy vehicles in the future really be able to "stop and charge" like mobile phones?

The market size is expected to exceed 200 million dollars

"At present, there are three charging methods defined in the industry: one is conductive charging using a charging gun, one is power exchange, and the other is wireless charging. From the development of the new energy vehicle industry, among the three charging methods, conductive charging has been comprehensively promoted, and various technologies have ushered in prosperity and development; the wind outlet of the power station is changing, and is preparing to make great efforts; New energy vehicle charging pile As for wireless charging, it is still in the process of industrialization. " Liu Yongdong, director of the Standardization Management Center of the China Electricity Council, said.

It is understood that the basic principle of wireless charging for electric vehicles is similar to that for mobile phones. At present, the wireless charging mode adopted at home and abroad is to install an energy receiving device on the vehicle chassis and an energy transmitting device on the ground. Through the conversion of electric field and magnetic field, the electric energy is sent from the ground end to the vehicle end and charged into the lithium battery. Compared with the mainstream wired charging and energy supplement mode, wireless charging does not need electrical connection, which avoids the possible electric spark when plugging and unplugging the charging gun head. It is convenient and fast, and it also greatly improves the safety and reliability.

Photo source: Visual China

According to the previous report of the global market research institute Markets and Markets, the scale of the global electric vehicle wireless charging market will increase from US $16 million in 2020 to US $234 million in 2027, with a compound annual growth rate of 46.8%.

The wireless charging information released by Volvo this time shows that the charging vehicle can automatically start the charging function by parking on the wireless charging device embedded in the road, and the driver does not need to get off the vehicle. Volvo Cars can use a 360 degree panoramic image to align the car with the wireless charging device, and the charging board can charge the on-board power management system at a power of more than 40kW as fast as 50kW wired DC charging.

In fact, behind the layout of wireless charging by automobile enterprises is the strong promotion and support of policies. The New Energy Vehicle Industry Development Plan (2021-2035) issued by the General Office of the State Council proposes to "strengthen the research and development of new charging technologies such as intelligent and orderly charging, high-power charging and wireless charging".

In addition, on October 11, 2021, the National Standardization Committee released the fifth, sixth and seventh parts of the electric vehicle wireless charging system, which will be officially implemented on May 1, 2022. Previously, the National Standardization Administration announced four national standards for electric vehicle wireless charging in China, which standardized the technical requirements, performance requirements, functional requirements, safety requirements, communication protocols, test requirements and methods, interoperability requirements and test methods, construction acceptance, operation and maintenance, etc. of electric vehicle wireless charging systems in public and private applications. Some people believe that although there is no mass production model supporting wireless charging in the domestic market at present, the introduction of this standard marks the acceleration of the popularization process of the wireless charging system for electric vehicles.

While vehicle enterprises are busy with layout, upstream and downstream enterprises are also stepping up the production and research and development of wireless charging piles. On March 7, Anjie Technology (002635. SZ) said on the investor interaction platform that the wireless charging pile of new energy vehicles is a part of the wireless charging system of new energy vehicles. The company's wireless charging system of new energy vehicles has obtained the cooperation of the new energy vehicle terminal brand customer designated project. In order to meet the customer's order demand, the company is currently expanding its capacity.

Wan'an Technology (002590. SZ), which has a stake in Evatran, a leading American wireless charging enterprise and a Tesla wireless charging supplier, said on the interactive platform in the second half of last year that the company's new energy vehicle wireless charging technology is basically mature and is about to enter the stage of small batch mass production. Shanghai Wanji Electronics, a holding subsidiary of the company, is a supporting supplier of BAIC BJEV and FAW Hongqi wireless charging products.

Commercialization still takes time

Although vehicle wireless charging technology has many advantages, it is still a long way from large-scale commercial promotion.

First of all, the vehicle wireless charging technology at the technical end is mainly faced with three difficulties: first, there are many application environment factors, different weather in the outdoor environment will have multiple impacts on the work of the wireless transmitting end, and heavy conditions such as wheel rolling should also be considered for indoor parking; Secondly, the parking accuracy is required to be high. The wireless charging adopts the electromagnetic induction principle. In order to ensure that each parking can be charged with the same efficiency, the position accuracy of the transmitting end and the receiving end is required to be very high. In practice, this may require the driver to perform more complex operations than plugging or unplugging the charging gun; The third is safety protection. The whole vehicle charging needs to ensure the safety of the charging environment at the transmitter, conduct foreign matter detection, live protection, etc., which is much more difficult than the wired charging protection process and technology.

Photo source: Photograph-400308592

"In the future, we need to further improve China's electric vehicle wireless charging technology system, effectively promote the development of industries with independent intellectual property rights, and more and more voice of China in international standards. At the same time, we need to focus on multidisciplinary integration, explore more technical directions in the field of electric vehicle wireless charging, break the technological monopoly of developed countries in new directions, and achieve curve overtaking." Song Kai, professor of the School of Electrical Engineering and Automation of Harbin Institute of Technology, said. New energy vehicle maintenance

In addition to technology, there are also many difficulties in the commercialization of wireless charging technology. In terms of Xingxing Charging, a charging pile enterprise, it believes that the wireless charging equipment has greatly changed the current vehicle structure, which requires the synchronous access of vehicle enterprises, and has high technical and patent barriers. It is expected that a demonstration station will be established in the short term in the form of cooperation between power equipment companies and vehicle enterprises. In China, although ZTE New Energy, Zhonghui Chuangzhi, Wan'an Technology and other manufacturers are also carrying out wireless charging technology layout and have launched relevant test charging stations, there is no large-scale commercial case yet.

In addition, at this stage, wireless charging of electric vehicles also faces the practical problem of high cost. "Equipment suppliers should systematically propose cost control strategies from product categories, standard systems, application scenarios and other aspects to meet the requirements of vehicle enterprises in terms of cost, volume, weight, safety and interoperability." Liu Yongdong suggested that electric vehicle wireless charging should grasp the market entry point and apply it in some vehicle terminals in stages, steps and scenarios, Improve product performance in corresponding product types and gradually promote industrialization.