CLEMSON, S.C. — If you’ve ever been on an airplane, you know every ounce of luggage matters. For astronauts planning a historic trip to Mars, it’s even more important. With that in mind, scientists at Clemson University say they have created a lighter and more efficient battery they hope will power NASA to the Red Planet.
The research by the Clemson Nanomaterials Institute (CNI) is replacing the graphite anode in a lithium-ion battery with silicon, which packs more of a charge. Researcher Ramakrishna Podila says this new technology could soon end up powering U.S. satellites.
“Most satellites mainly get their power from the sun,” the assistant professor in Clemson’s College of Science says in a release. “But the satellites have to be able to store energy for when they are in the Earth’s shadow. We have to make the batteries as light as possible, because the more the satellite weighs, the more its mission costs.”
Stacking the deck
The Clemson team compares batteries to a deck of cards, where each layer of graphite represents another card in the box. The problem with graphite is it can’t hold much of a charge.
Using silicon, batteries can store more energy until it’s time to use them. The reason scientist have avoided using silicon in the past is because the material breaks apart too easily when it charges and discharges electricity.
To solve this issue, CNI uses “nanosized” particles of silicon which are more stable and last longer. Researchers then take layers of a carbon nanotube material, Buckypaper, to sandwich all the tiny silicon particles together. Even when these nanoparticles break apart while charging, Podila says it’s alright because they’re “still in the sandwich.”
“The freestanding sheets of carbon nanotubes keep the silicon nanoparticles electrically connected with each other,” adds study author Shailendra Chiluwal.
How will these batteries speed up mission to Mars?
Aside from holding more energy, the study finds using silicon and other nanomaterials also helps batteries charge faster. The Buckypaper helps buffer these cells, allowing them to charge at a higher current and regenerate at four times the rate of current batteries.
A lighter battery that charges four times as fast will be a huge advantage to NASA, who is funding the research. That’s because the space agency is looking to power new spacesuits and vehicles which may soon head to Mars.
“Silicon as the anode in a lithium-ion battery represents the ‘holy grail’ for researchers in this field,” CNI director Apparao M. Rao explains.
Rao adds these batteries aren’t just heading to space, they may also be hitting the roads in electric cars too.
The study appears in the journal Applied Materials and Interfaces.