No need for electric piles, charging while walking
Wireless charging is expected to relieve EV 'range anxiety'
[World Tide of Technological Innovation]
One of the biggest barriers to EV adoption is charging, or the lack of charging infrastructure. "Range anxiety" is common among car owners, who worry about running out of battery and being stuck far away from EV charging stations. However, what if the car charging does not need a charging pile at all?
According to a report recently released by Nikkei Asia, roads with built-in wireless charging technology have been tested in Japan and by 2025, may become a practical facility.
At the Obayashi-gumi Research Center of the construction company in Tokyo, Japan, electric vehicles can travel at speeds of up to 15 kilometers per hour on such roads. Uninterrupted electronic coils are buried under the surface of the road, and electric vehicles also have separate coils installed inside, which use magnetic field induction to generate current in the car's coils. The concrete used in the pavement is reinforced with fibers for added durability. Driverless buses that operate 24/7 will be one of the main beneficiaries of this breakthrough technology.
However, the report added that the technology is still far from perfect. It states that wireless charging is not as effective as using traditional cables due to transmission losses.
At present, not only in Japan, enterprises and institutions in many countries and regions have carried out research on wireless charging of electric vehicles, trying to fundamentally solve the problem of "range anxiety".
The idea is not new
In fact, people have long been accustomed to wirelessly charging their smartphones. The Gizmodo website, a well-known American technology blog, posted on September 20 that the wireless charging alliance, a global standardization organization that promotes wireless charging technology, launched the first "wireless charging" standard QI in 2008. The first widely used phone to adopt the QI standard was the Nokia Lumia 920 in 2012.
This technology can be traced back to 1894, when science giant Nikola Tesla used resonant inductive coupling to wirelessly light incandescent light bulbs in New York City, so the idea of wirelessly transmitting electricity is actually not new. Demonstration facilities have been installed or are under construction in many parts of the world.
In 2017, a 100-meter-long section of French road was installed with wireless charging. When the car travels at a speed of 40 kilometers per hour on this "wireless road", it can charge an additional charge of about 2 kilometers for each kilometer traveled. . Vehicles can travel up to 100 kilometers per hour on this road.
In 2018, electric rails were installed on a 2-kilometer road in Sweden, with charging facilities on the central axis. A special device is attached to an electric vehicle and it drops into a groove in the rails to charge the car while driving. It's like the track racers we played as kids, just swapping the toy cars for real cars.
In 2020, Israel installed a wireless charging cable on a 600-meter long road. The technology is being tested and, if all tests are successful, an 18km bus lane between the city and the airport will be built.
In June, Italy built a 1.05km dedicated wireless charging road to demonstrate dynamic wireless power transfer. The road has electric wires built into the tarmac, and vehicles can harvest electricity through special receivers. When the car is traveling at 40 kilometers per hour, it can be charged at a rate of 1.5 kilometers per kilometer traveled.
In 2023, Detroit, the United States will put into use a 1.6-kilometer-long wireless charging road. This road will be transformed. At that time, cars with special receivers installed on the bottom of the car will be able to charge while driving on the road.
How far is the future
Like many other emerging technologies that are gradually entering the mainstream market, in-vehicle wireless charging is still immature and still faces many technical problems to overcome.
The eetasia.com website reported that the positioning of wireless charging is not to completely replace wired charging, but to provide a convenient experience. This means that electric vehicles can use the wireless charging mode in public places or outdoors, and can be charged directly without wiring after parking, and there is no need to unplug the charging cable when driving away; and when used outdoors, even in snow, water It is also safe to charge under conditions such as dust pollution.
According to the article, from the technical point of view of wireless charging for electric vehicles, the biggest R&D challenges are safety and mass production.
Wireless charging is the transfer of power wirelessly. Even low-power 5W wireless charging on mobile phones faces many safety issues, including electromagnetic interference, heat generation, and metal foreign objects. The biggest safety threat is metallic foreign objects, which absorb electromagnetic energy and heat up violently, with catastrophic consequences. The charging power of electric vehicles is a thousand times more than that of mobile phones, and the threat of metal foreign objects will be more serious. In system design, it is necessary to monitor the presence of threatening metallic foreign objects between the battery terminals.
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Issues with mass production include validation, reliability, and cost. The first issue encountered in commercial mass production is the associated regulatory certification. Wireless charging products themselves are powerful transmitters of electromagnetic energy, and it is difficult to pass relevant electromagnetic interference regulations; the coils in the system are very unstable components, and their characteristics will change due to the interference of various factors such as production deviation and temperature. The system needs to overcome the coil factor through an adjustment mechanism to keep its function running. The biggest problem in mass production is cost. Currently, the cost of wireless charging systems for electric vehicles is very high.
The American media Auto World website reported that many players, including automakers such as Nissan, BMW and Renault, have been exploring wireless technology for many years. In fact, the BMW 530e inductive charging pilot was named Green Car Technology of the Year 2020 by Green Car Magazine. However, it has yet to "take off" in any meaningful way. High costs and lack of standards are stumbling blocks holding back the development of wireless charging in cars.
Overall, given the trend towards energy conservation and green energy development, wireless charging solutions for electric vehicles are expected to grow at a considerable rate in the next few years. As the future of transportation continues to innovate through disruptive technologies, worrying about where to charge electric vehicles may soon be a thing of the past.
