Jetpacks, robot-made cars, and flying cars were all promises of the 21st century. Instead, I got a mechanized autonomous vacuum cleaner. Currently, a team of researchers at Penn State University is investigating the requirements for electric vertical takeoff and landing (eVTOL) vehicles and designing and testing potential battery power supplies.
“I think flying cars have the potential to save a lot of time, increase productivity and open up empty corridors for transportation,” said William E. Defender, Director of Mechanical Engineering and Director of Electrochemical Engine Center. Chao Yang Wan says. , Pennsylvania State University. “But electric vertical take-off and landing aircraft is a very challenging technology for batteries.”
Researchers have defined the technical requirements for in-flight car batteries and reported on prototype batteries on June 7, 2021. Jules..
“Batteries for flying cars require very high energy densities so that they can stay in the air,” Wang said. “It also requires very high power during takeoff and landing. It takes a lot of power to move vertically up and down.”
Wang says the batteries also need to be recharged quickly to make a lot of money during rush hours. He sees these vehicles take off and land frequently and recharge quickly and frequently.
“Commercially, we expect these vehicles to make 15 trips twice a day during rush hours to justify the cost of the vehicle,” Wang said. I will. “The first use will probably carry 3-4 people from the city to the airport in about 50 miles.”
Weight is also a consideration for these batteries, as the vehicle must lift and land the batteries. According to Wang, when eVTOL takes off, it will average 100 mph on short trips and 200 mph on long trips.
Researchers have experimentally tested two energy-dense lithium-ion batteries that can be recharged with sufficient energy for a 50-mile eVTOL trip in 5-10 minutes. These batteries can withstand over 2,000 fast charges over their lifetime.
The king and his team used the technology they have been working on for electric vehicle batteries. The important thing is to heat the battery so that it can be quickly charged without damaging the battery and forming dangerous lithium spikes. You can see that when the battery is heated, the energy held in the battery is rapidly discharged, allowing takeoff and landing.
Researchers heat the battery by incorporating nickel foil that rapidly raises the battery to 140 degrees Fahrenheit.
“Under normal circumstances, the three attributes required for an eVTOL battery interact,” Wang said. “High energy density reduces fast charging, and fast charging reduces the number of recharge cycles that are normally possible, but one battery can do all three.”
One of the completely unique aspects of a flying car is that the battery must always hold some charge. For example, unlike cell phone batteries, which work best when fully discharged and recharged, flying car batteries need power to stay in the air and land, so they should be fully discharged in the air. You can not. The battery of a flying car always needs a safety margin.
When the battery is empty, it has less internal resistance to charging, but the more charge it has left, the harder it is to push more energy into the battery. Charging usually slows when the battery is full. However, by heating the battery, the recharge can only be in the 5-10 minute range.
“I hope the work we’ve done in this treatise gives people a solid idea that it won’t take another 20 years to finally get these vehicles,” Wang said. I will. “I think we’ve demonstrated that eVTOL is commercially viable.”
Reference: June 7, 2021, “Batteries for Electric Vertical Takeoff and Landing Aircraft Challenges and Important Requirements” by Xiao-Guang Yang, Teng Liu, Shanghai Ge, Eric Rountree, Chao-Yang Wang Jules..
DOI: 10.1016 / j.joule.2021.05.001
The project was also undertaken by Xiao-Guang Yang and Shanhai Ge, both assistant professors of mechanical engineering, and Teng Liu, a PhD student in mechanical engineering. Eric Round Tree of EC Power at State College, Pennsylvania.
The study was funded by the US Department of Energy’s Energy Efficiency and Renewable Energy Authority, the US Air Force SME Technology Transfer Program, and the William E. Defender Farr Foundation.
Innovative Battery Technology Puts Flying Cars on the Horizon Source link Innovative Battery Technology Puts Flying Cars on the Horizon