The development of new energy vehicles is in full swing, and the issue of energy replenishment has also become one of the issues that the industry has paid full attention to. While everyone is debating the merits of overcharging and battery swapping, is there a "Plan C" for charging new energy vehicles?
Perhaps influenced by wireless charging of smartphones, wireless charging of cars has also become one of the technologies that engineers have overcome. According to media reports, not long ago, car wireless charging technology received breakthrough research. A research and development team claimed that the wireless charging pad can transmit power to the car with an output power of 100kW, which can increase the battery charge status by 50% within 20 minutes.
Of course, car wireless charging technology is not a new technology. With the rise of new energy vehicles, various forces have been exploring wireless charging for a long time, including BBA, Volvo and various domestic car companies.
Overall, car wireless charging technology is still in its early stages, and many local governments are also taking this opportunity to explore greater possibilities for future transportation. However, due to factors such as cost, power, and infrastructure, car wireless charging technology has been commercialized on a large scale. There are many difficulties that still need to be overcome. The new story about wireless charging in cars is not easy to tell yet.
As we all know, wireless charging is nothing new in the mobile phone industry. Wireless charging for cars is not as popular as charging for mobile phones, but it has already attracted many companies to covet this technology.
Overall, there are four mainstream wireless charging methods: electromagnetic induction, magnetic field resonance, electric field coupling, and radio waves. Among them, mobile phones and electric vehicles mainly use electromagnetic induction and magnetic field resonance.
Among them, electromagnetic induction wireless charging uses the electromagnetic induction principle of electromagnetism and magnetism to generate electricity. It has high charging efficiency, but the effective charging distance is short and the charging location requirements are also strict. Relatively speaking, magnetic resonance wireless charging has lower location requirements and a longer charging distance, which can support several centimeters to several meters, but the charging efficiency is slightly lower than the former.
Therefore, in the early stages of exploring wireless charging technology, car companies favored electromagnetic induction wireless charging technology. Representative companies include BMW, Daimler and other vehicle companies. Since then, magnetic resonance wireless charging technology has gradually been promoted, represented by system suppliers such as Qualcomm and WiTricity.
As early as July 2014, BMW and Daimler (now Mercedes-Benz) announced a cooperation agreement to jointly develop wireless charging technology for electric vehicles. In 2018, BMW began to produce a wireless charging system and made it an optional device for the 5 Series plug-in hybrid model. Its rated charging power is 3.2kW, the energy conversion efficiency reaches 85%, and it can be fully charged in 3.5 hours.
In 2021, Volvo will use the XC40 pure electric taxi to start wireless charging experiments in Sweden. Volvo has specially set up multiple test areas in urban Gothenburg, Sweden. Charging vehicles only need to park on the wireless charging devices embedded in the road to automatically start the charging function. Volvo said that its wireless charging power can reach 40kW, and it can travel 100 kilometers in 30 minutes.
In the field of automotive wireless charging, my country has always been at the forefront of the industry. In 2015, China Southern Power Grid Guangxi Electric Power Research Institute built the first domestic electric vehicle wireless charging test lane. In 2018, SAIC Roewe launched the first pure electric model with wireless charging. FAW Hongqi launched the Hongqi E-HS9 that supports wireless charging technology in 2020. In March 2023, SAIC Zhiji officially launched its first 11kW high-power vehicle intelligent wireless charging solution.
And Tesla is also one of the explorers in the field of wireless charging. In June 2023, Tesla spent US$76 million to acquire Wiferion and renamed it Tesla Engineering Germany GmbH, planning to leverage wireless charging at a low cost. Previously, Tesla CEO Musk had a negative attitude towards wireless charging and criticized wireless charging as "low energy and inefficient". Now he calls it a promising future.
Of course, many car companies such as Toyota, Honda, Nissan, and General Motors are also developing wireless charging technology.
Although many parties have conducted long-term explorations in the field of wireless charging, automotive wireless charging technology is still far from becoming a reality. The key factor restricting its development is power. Take the Hongqi E-HS9 as an example. The wireless charging technology it is equipped with has a maximum output power of 10kW, which is only slightly higher than the 7kW power of the slow charging pile. Some models can only achieve a system charging power of 3.2kW. In other words, there is no convenience at all with such charging efficiency.
Of course, if the power of wireless charging is improved, it may be another story. For example, as stated at the beginning of the article, a research and development team has achieved an output power of 100kW, which means that if such an output power can be achieved, the vehicle can theoretically be fully charged in about an hour. Although it is still difficult to compare with super charging, it is still a new choice for energy replenishment.
From the perspective of usage scenarios, the biggest advantage of automotive wireless charging technology is the reduction of manual steps. Compared with wired charging, car owners need to perform a series of operations such as parking, getting off the car, picking up the gun, plugging in and charging, etc. When facing third-party charging piles, they have to fill in various information, which is a relatively cumbersome process.
The wireless charging scenario is very simple. After the driver parks the vehicle, the device automatically senses it and then wirelessly charges it. After the vehicle is fully charged, the vehicle drives away directly, and the owner does not need to perform any more operations. From the perspective of user experience, it will also give people a sense of luxury when using electric vehicles.
Why does car wireless charging attract so much attention from enterprises and suppliers? From a development perspective, the arrival of the driverless era may also be a time for great development of wireless charging technology. For cars to truly be driverless, they need wireless charging to get rid of the shackles of charging cables.
Therefore, many charging suppliers are very optimistic about the development prospects of wireless charging technology. German giant Siemens predicts that the wireless charging market for electric vehicles in Europe and North America will reach US$2 billion by 2028. To this end, as early as June 2022, Siemens invested US$25 million to obtain a minority stake in wireless charging supplier WiTricity to promote technology research and development of wireless charging systems.
Siemens believes that wireless charging of electric vehicles will become mainstream in the future. In addition to making charging more convenient, wireless charging is also one of the necessary conditions for realizing autonomous driving. If we really want to launch self-driving cars on a large scale, wireless charging technology is indispensable. This is an important step into the world of autonomous driving.
Of course, the prospects are great, but the reality is ugly. At present, the energy replenishment methods of electric vehicles are becoming more and more diverse, and the prospect of wireless charging is highly anticipated. However, from the current point of view, automotive wireless charging technology is still in the testing stage and faces many problems, such as high cost, slow charging, inconsistent standards, and slow commercialization progress.
The problem of charging efficiency is one of the obstacles. For example, we discussed the issue of efficiency in the aforementioned Hongqi E-HS9. The low efficiency of wireless charging has been criticized. Currently, the efficiency of wireless charging of electric vehicles is lower than that of wired charging because of energy loss during wireless transmission.
From a cost perspective, car wireless charging needs to be further reduced. Wireless charging has high requirements for infrastructure. Charging components are generally laid on the ground, which will involve ground modification and other issues. The construction cost will inevitably be higher than the cost of ordinary charging piles. In addition, in the early stage of the promotion of wireless charging technology, the industrial chain is immature, and the cost of related parts will be high, even several times the price of household AC charging piles with the same power.
For example, the British bus operator FirstBus has considered using wireless charging technology in the process of promoting the electrification of its fleet. However, after inspection, it was found that each supplier of ground charging panels quoted 70,000 pounds. In addition, the construction cost of wireless charging roads is also high. For example, the cost of building a 1.6-kilometer wireless charging road in Sweden is approximately US$12.5 million.
Of course, safety issues may also be one of the issues restricting wireless charging technology. From the perspective of its impact on the human body, wireless charging is not a big deal. The "Interim Regulations on Radio Management of Wireless Charging (Power Transmission) Equipment (Draft for Comments)" published by the Ministry of Industry and Information Technology states that the spectrum of 19-21kHz and 79-90kHz is exclusive for wireless charging cars. Relevant research shows that only when the charging power exceeds 20kW and the human body is in close contact with the charging base, it may have a certain impact on the body. However, this also requires all parties to continue to popularize safety before it can be recognized by consumers.
No matter how practical the car wireless charging technology is and how convenient the usage scenarios are, there is still a long way to go before it can be commercialized on a large scale. Going out of the laboratory and implementing it into real life, the road to wireless charging for cars is long and arduous.
While all parties are vigorously exploring wireless charging technology for cars, the concept of "charging robots" has also quietly emerged. The pain points to be solved by wireless charging represent the issue of user charging convenience, which will complement the concept of driverless driving in the future. But there is more than one road to Rome.
Therefore, "charging robots" have also begun to become a supplement in the intelligent charging process of automobiles. Not long ago, the Beijing Sub-Central Construction National Green Development Demonstration Zone’s new power system experimental base launched a fully automatic bus charging robot that can charge electric buses.
After the electric bus enters the charging station, the vision system captures the vehicle's arrival information, and the background dispatch system immediately issues a charging task to the robot. With the assistance of the pathfinding system and walking mechanism, the robot automatically drives to the charging station and automatically grabs the charging gun. , using visual positioning technology to identify the location of the electric vehicle charging port and perform automatic charging operations.
Of course, car companies are also beginning to see the advantages of “charging robots”. At the 2023 Shanghai Auto Show, Lotus released a flash charging robot. When the vehicle needs to be charged, the robot can extend its mechanical arm and automatically insert the charging gun into the vehicle's charging hole. After charging, it can also pull out the gun on its own, completing the entire process from starting to charging the vehicle.
In contrast, charging robots not only have the convenience of wireless charging, but can also solve the power limitation problem of wireless charging. Users can also enjoy the pleasure of overcharging without getting out of the car. Of course, charging robots will also involve cost and intelligent issues such as positioning and obstacle avoidance.
Summary: The issue of energy replenishment for new energy vehicles has always been an issue that all parties in the industry attach great importance to. At present, the overcharging solution and the battery replacement solution are the two most mainstream solutions. Theoretically, these two solutions are sufficient to meet the energy replenishment needs of users to a certain extent. Of course, things are always moving forward. Perhaps with the advent of the driverless era, wireless charging and charging robots may usher in new opportunities.
Post time: Apr-13-2024