Like the charging suit worn in the Marvel comic Strip Black Panther, researchers at the University of California, San Francisco, using advanced NASA technology, have developed a power suit for electric vehicles that is as strong as steel and lighter than aluminum, helping to increase the car's power capacity.
Kumar and Pandey are UCF PhD students, and Thomas is a professor at the UCF Center for Nanoscience and the Department of Materials Science and Engineering.
UCF researchers Kowsik Sambath Kumar, Jayan Thomas and Deepak Pandey demonstrated a hybrid composite of lightweight supercapacitor batteries they developed.
Today's electric vehicles (EVs) face many challenges, such as limited charging capacity, low charging range, and long charging times. The new research addresses these issues by developing an energy storage carbon fiber reinforced polymer (e-CFRP) based on a dual-function supercapacitor that can store electrical energy and serve as a structural part of an electric vehicle body shell.
This was achieved by developing a unique design where vertically arranged graphene sheets are attached to carbon fiber electrodes, where different metal oxides are deposited to obtain high energy density electrodes. High-strength multilayer e-CFRP components were prepared using alternating layered structures of epoxy resin and polyacrylamide gel electrolyte.
The e-CFRP thus developed has a surface energy density of 0.31 mWh cm-2, tensile strength of 518 MPa, flexural strength of 477 MPa and impact strength of 2666J m-1 at a thickness of 0.3 mm.
To demonstrate its application in electric vehicles, the body panel of a toy car is made with e-CFRP, and the toy car is capable of operating using the energy stored within its frame. In addition, when combined with solar cells, this composite material can power IoT devices, showing their feasibility in communications satellites.
Schematic diagram of electrode preparation and energized composite material manufacturing and application. a-c) Manufacture of electrodes. d-f) The use of electrodes to manufacture charged composites and their applications in body prototyping.
The advance, which recently appeared as a cover story for Small magazine, could be applied to a range of technologies that require lightweight energy, from electric vehicles to spacecraft, airplanes, drones, portable devices and wearable technologies.
"The idea is to use a housing to store energy to supplement the energy stored in the battery," said Jayan Thomas, a collaborator in the study and a professor and team leader at the UCF Center for Nanoscience and the Department of Materials Science and Engineering.
"The advantage of this composite material is that it can reduce the weight of the car and increase the mileage per charge," he said. "It's even stronger than steel, but much lighter."
When this material is used as a car shell, it can increase the range of electric vehicles by 25%, which means that cars can travel 50 more miles per 200 miles charged, and reduce the total weight of the car.
As a supercapacitor, it can also boost the power of an electric car, giving it extra thrust that accelerates from 0 to 60 mph in 3 seconds.
These materials could be used as frames for CubeSats, structures for exoplanet habitats, and even as part of future glasses, such as mixed reality and virtual reality headsets.
In cars, Roberson says, supercapacitor composites will get electricity through charging, such as batteries, as well as when the car brakes.
"It has a charge-discharge cycle life of 10 times that of an electric vehicle battery," he says, "and the materials used are also non-toxic and non-flammable, which is very important for the safety of passengers in the event of an accident."
Thomas said: "This is a huge step forward compared to past methods, which have problems with toxic materials, flammable organic electrolytes, low life cycles or poor performance. ”
Due to its unique design using multiple layers of carbon fiber, the material has significant impact strength and flexural strength, which is essential for withstanding car crashes, while also having significant tensile strength.
To build the material, the researchers fabricated layers of positively and negatively charged carbon fibers that, when stacked and joined in alternating patterns, form a powerful energy storage composite.
Parity position pattern for depositing active materials on cross-braided carbon fiber pads. b) Stacking patterns of anode and cathode carbon fiber pads to make large areas of energized composites.
Nanoscale graphene sheets attached to the carbon fiber layer improve charge storage capacity, while metal oxides deposited on the attached electrodes increase voltage and provide higher energy density. Thomas says this provides an unprecedented amount of energy storage capacity and charging cycles for supercapacitor-battery hybrids.
The study's lead author, Deepak Pandey, a doctoral student in Thomas's lab, worked on the preparation, molding, and optimization of composites, as well as developing methods for adding metal oxides to carbon graphene belts.
The study's collaborator, Kowsik Sambath Kumar, a doctoral student in Thomas's lab, has developed a method of arranging nanographene vertically on carbon fiber electrodes.
Kumar says one of the most important developments in this supercapacitor composite is its light weight.
"Now in electric vehicles, batteries make up 30 to 40 percent of the weight," he said. "Using this energy storage composite, we can increase the mileage without increasing the weight of the battery, further reducing the weight of the vehicle while maintaining high tensile, bending and impact strength." Every time you lose weight, you can increase the range, so this has huge applications in electric vehicles and aviation. ”
"Making a CubeSat with this composite material will make the satellite lighter and help eliminate bulky battery packs," he said. "This could save thousands of dollars per launch." In addition, the free volume gained by removing large batteries can help load more sensors and test equipment, thereby increasing the functionality of the satellite," Pandey said. "Supercapacitor-battery hybrid behavior is ideal for CubeSats. Because when the satellite is running on the sunny side of the earth, it can be charged in a few minutes.
Roberson says the technology is currently at level 5 readiness, which means it's already being tested in the relevant environment before it's tested in a real-world environment, such as in spaceflight, which would be a level 6 test.
In order to pass the final level of testing, level 9, and reach the commercial environment, he said, it will require further development and testing, with a focus on commercial applications.
Literature:
Deepak Pandey et al,Energized Composites for Electric Vehicles: A Dual Function Energy‐Storing Supercapacitor‐Based Carbon Fiber Composite for the Body Panels,Small(2022). DOI: 10.1002/smll.202107053