A paste, a release, a dazzling turn, charging begins. I believe that many people who have experienced wireless charging of cell phones are familiar with this process, but also to this light and convenient, almost senseless way to replenish energy can not stop. People who have experienced wireless charging are like people who have driven electric cars and can never go back. Ask yourself if you remember the last time you plugged in your phone to charge it?
Imagine if a company could take the wireless charging of cell phones and pan it to electric cars. What a clear impact that would have on the existing ways of replenishing electric vehicles – public piles, home charging piles, and power swaps.
Park, get out, lock the doors, and start charging. Wake up and go with a full charge. In this scenario, charging is really more convenient than refueling, as Azure Li Bin said. Those who are waiting for the national football team to enter the World Cup and then buy an electric car, look at the regret.
But doubts follow, this strong enough to directly let the fuel car run into the history books of technology, why until today, is still a minority to experience the tasting products, can not really go into the ordinary people’s car space?
The reason is that, at this stage of wireless charging, and the imagination of the good, a little relationship does not match.
Tesla’s trick, testy broken waist
Looking back at history, wireless charging (Wireless Charging) this technology, the wizard of the ages Tesla (Nikola Tesla) played more than 100 years ago, and play fancier than now.
In the summer of 1901, the scientist, who had been depressed by Edison’s theft of the patent for DC generator technology, was approached by John Pierpont Morgan, the American capitalist and “debtor of the world”. Morgan judged that the mainstream of the world after wireless communications so gave Tesla $ 150,000 and a large piece of open land for him to study radio.
With money and land, Tesla soon built a giant tower 57 meters high with a 20-meter diameter hemisphere at the top, which became known as the “Waldenkliff Tower”.
Waldenkreifta
Genius Tesla only took a month to drum up the doorway of wireless communication, but he did not immediately report to the boss. The reason is to put such fertile funds, land and giant towers not to realize their own super plan, more or less seems a bit wasteful.
This super plan is: global wireless power transmission.
Wireless transmission and wireless broadcasting are essentially the same, are dependent on the transmission and reception of radio waves. If the experiment is successful, all the equipment on the planet where electricity is used as an energy source can be charged without carrying batteries, and wireless transmission at any time. Flashlights, vacuum cleaners, radios, cell phones, electric cars, etc.
If this technology is successful, it means that “King Ning” was sentenced to death in advance before it was born.
Unfortunately, Morgan soon found out that Tesla is not doing the right thing “small mind”, stop funding his experiments. Tesla lost the owner, but also suffered a sudden fire in the laboratory during the “water” event, the research data was a fire burned to the ground.
The good thing is that the thinking model of “wireless power transmission” was preserved: the earth as a conductor of power transmission, through the ground Tesla coil, alternating current pulses are delivered to the ground and the ionosphere in the resonant cavity to form electromagnetic resonance, electricity in the atmosphere continuously propagated. Any place on earth with a resonant capacitor antenna can receive AC power from the air.
Four big words flow-saving version is: electromagnetic induction.
But the seemingly flawless wireless transmission has two obvious technical flaws: first, electromagnetic radiation, which you can see in the prices of properties next to high-voltage lines; and second, transmission efficiency, where electromagnetic waves spread outward in transmission, causing a rapid decline in efficiency. If you set up a 1 million watts of wireless energy transmitter, you must always inject 1 million watts of power into it, even if the demand on the electricity side is only 10 watts.
Long distance, high-power wireless transmission loss is too large, then we might as well start with a short distance, small power. Now almost become standard cell phone wireless charging, is to rely on the induction range of the two iron rings to form a pathway to achieve short-range radio energy transmission, the official name of this technology is called “magnetic induction coupling technology”.
How small can the power be? According to the Ministry of Industry and Information Technology issued on February 19 last year, “wireless charging (power transmission) equipment radio management interim regulations (draft for comment)” in the regulations are: can not exceed 50 watts.
50 watts is enough for cell phones and electric toothbrushes, but for electric cars, it’s a drop in the bucket. You know, the slow charging power of electric cars is between 7 to 15 kilowatts, full of a car to 6 to 8 hours. 50 watts of this power, charging horse certainly can not run, electric horse model is almost.
Faced with the dilemma that long distance and high power cannot be achieved in electric vehicles, and short distance and low power have no application value, engineers have racked their brains to come up with a compromise: short distance and high power.
The dawn, it seems, is ahead.
It still has to be a technology company
Building electric cars are the business of car companies, but it’s up to technology companies to solve the wireless charging problem.
In 2013, before the Frankfurt Motor Show, Qualcomm announced that it would be the first to apply Halo wireless charging technology in the Formula E electric racing championship. 2 years later, in the second season, a wirelessly chargeable BMW i8 safety car entered the public eye, announcing in a high profile manner that “the technology that will turn the world of electric cars upside down” is here. The technology that “turned the world of electric cars upside down” was here.
Qualcomm Halo wireless charging kit consists of a power supply, transmitter panel, onboard receiver panel and controller, which are not linked by any cable.
The biggest highlight of the magnetic field resonance wireless charging technology is that the requirement of connection accuracy is not so high, a certain position error is allowed between the transmitting panel and the receiving panel, but this error should not be too exaggerated. At the same time, when the vehicle is in position and the charging panel is combined, the cell phone APP will remind the vehicle’s position and automatically turn on the wireless charging mode after parking, which is highly suitable for the automatic driving scenario.
The BMW i8 safety car has 7.2 kilowatts of wireless charging power, twice the 3.6 kilowatts of the previous year’s lab product, and can bring the i8 back to full power in less than an hour. At the same time, Qualcomm has boosted wireless charging efficiency to 90 percent, nearly tying it with cable charging efficiency.
The safety car driver has said that the most satisfying part of the car is that he can park it and get out of there without having to deal with dirty, heavy cables after a hard day’s work.
Qualcomm engineers have revealed that Halo can adjust the charging power according to the user’s requirements, and at that time the range of support is 6.6 kilowatts to 20 kilowatts, which means that a full 85-degree battery pack Tesla Model S P85 just 4 hours and 25 minutes.
As for why the BMW i8 was chosen as the subject of the experiment, Qualcomm gave a simple reason, because it is a sports car with low ground clearance, closer to the charging panel, and more efficient in charging transmission. In the second generation of Halo, Qualcomm has adjusted the wireless charging sensing distance range to 15 mm to 200 mm, which means that both sports cars and SUVs can be used.
Then the problem also comes, the chassis can not and charging panel zero distance fit, there is always a gap, the maximum 200 mm gap is not to be underestimated. If a centipede-like critter crawls in, or a napkin that comes with the wind, a plastic bag, or a lone leaf is blown in, won’t it burn up quickly?
Qualcomm has long thought of this, the solution is to add a set of foreign body detection and biological body protection system, once the charging on the way to the above phenomenon, will automatically stop the charging operation, and immediately through the APP push to remind the owner.
For wireless charging, in addition to safety, people have another concern: electromagnetic radiation, of which “electromagnetic radiation will not cause harm to my body” is the most asked.
The answer given by Qualcomm in 2016 is that Halo works with a magnetic induction strength of about 100μT (micro-Tesla), the International Commission on Non-Ionizing Radiation Protection (ICNIRP) organization gives the international common magnetic induction strength reference value of 200μT, and the magnetic induction strength of 220μT when talking on a cell phone. If you are worried about the electromagnetic radiation caused by wireless charging, you should throw away your cell phone first, and throw it as far as you can.
Although wireless charging has been on people’s radar since 2013, production vehicles with wireless charging capabilities have been extremely limited until today. In 2018, BMW adapted wireless charging to the 530e iPerformance hybrid sedan with 3.3 kilowatts, half the power of a slow charger, and taking three hours to fill a 9.2-degree battery.
Sadly, in 2019 Qualcomm sold its Halo division in its entirety to startup WiTricity, which received a $25 million investment from Siemens in June, and is now delivering wireless charging kits that support up to 11 kilowatts of power and can add 56 kilometers of range per hour to an electric vehicle.
Volvo this year pushed the peak power of wireless charging up to 40 kW, which is comparable to a 50 kW DC fast charger and about four times faster than an 11 kW AC charger, charging the XC40 battery from 0 to 100 percent in about 100 minutes.
XC40 is charging wirelessly
Siemens, which has invested in WiTricity, believes that wireless charging will reach $2 billion in both European and North American markets by 2028, while WiTricity found in its research that consumer purchase intent for electric vehicles increased from 35% to 59% with wireless charging.
Alex Gruzen, CEO of WiTricity, defines wireless charging as a scenario-specific technology for everyday charging, not road trips, a definition that pinpoints the highly limited nature of wireless charging, but a self-conscious lapse of words quickly finds a way to add.
Ultimately, you’ll feel like you have a car with unlimited mileage. There’s no extra work to do except driving and parking.
Are the Chinese buying it?
Globally, wireless charging seems to be a sunrise industry that is a sure thing: capital-friendly, consumer-oriented, technologically focused, environmentally supportive, and with no major flaws other than being a little more expensive (around $3,500 for retrofit).
However, the past did not fire wireless charging, the future can fire, but also depends on the face of the Chinese market.
Engine technology is by Europeans, Americans buy progress, that electric car technology progress behind the biggest gold dollar host, no doubt the Chinese.
Let’s look at two cases.
The first is SAIC Zhiqi, whose L7 claims to be the first mass-produced model to support high-power wireless charging, with a maximum power of 11 kilowatts and a maximum efficiency of more than 90%.
To use Zhiqi wireless charging, you need three conditions: first, a fixed indoor parking space (underground or canopy); second, consent from the property; and third, the installation of a 380V three-phase electric meter.
In addition to these three hard conditions, there is also a significant cost: $6,000 for the car-side smart wireless charging module, $18,999 for the wireless charging pile, and $12,000 after offsetting the price of the 7 kW home charging pile, for a total of $18,000.
A Jiji L7 user waiting to pick up the car told Tiger that he was personally very interested in wireless charging and was strongly attracted to this point at that time. “The problem is that my wife hasn’t agreed,” the user said, “she always thinks there’s radiation and it’s not good for having a third child.”
Another one is Huawei.
It is said that the world’s electric vehicles look at China, China’s electric vehicles look at Huawei. In wireless charging, on May 25 last year, Huawei disclosed a patent for “a wireless charging parking space parking recommendation method and system”, which simply matches the function of parking lot automatic parking with wireless charging to achieve senseless automatic parking into wireless charging parking space.
Compared to the IM L7 for home scenarios, Huawei’s solution expands the scenario outreach of wireless charging technology applications. But there are many problems, for example, with Huawei added more and more car companies, ask the world, pole fox, Avita, Ean, whether the technology can be enjoyed through the rear installation; and then other brands with the function of the model can enjoy Huawei services, in case the charging time burned up, how to divide the responsibility ……
Although tough, Chinese auto companies generally believe that wireless charging is the right path to take. So far, FAW, Changan, Geely, SAIC, BAIC, GAC, BYD, etc., have all made technical arrangements for wireless charging.
The New Energy Vehicle Industry Development Plan (2021-2035) also focuses on “accelerating the construction of charging and switching infrastructure” to strengthen the research and development of new charging technologies such as intelligent and orderly charging, high-power charging and wireless charging.
It seems that the Chinese not only buy wireless charging but also buy a lot.
Write in the end
The insufficient range is the biggest pain point of electric vehicles, before battery technology advances by leaps and bounds, people can only put their hope on the best possible way to replenish energy, after all, the fuel car travels thousands of miles a day, the gas stations are spread all over the place.
In the existing energy replenishment methods, the fastest and most efficient is the power exchange. The disadvantage is that the batteries of different car brands are not common, the exchange station needs to reserve a large number of batteries, high construction and maintenance costs, and high cost of a single replenishment.
The relative balance of speed and efficiency is wired charging, the disadvantage is that frequent plugging and unplugging is easy to cause cable wear and aging, line breakage brings leakage and other safety hazards, and the adaptability to bad weather needs to be improved.
Wireless charging covers a small area, easy to operate, has a less mechanical connection, low damage rate, and immersion to replenish energy. Explicit disadvantages are high front cost and low charging efficiency. The hidden type disadvantage is the public’s doubts about electromagnetic radiation, which started from the era of the bp machine and has not seen any improvement until today.
Of course, now the wireless charging is still in the most elementary static stage, the end of the technology is dynamic wireless charging, charging while driving, as long as people do not stop, electric cars always have power, solve the range anxiety, a hand to kill the fuel car.
At that point, perhaps the electric car will become a proper vehicle.
