Lithium-ion batteries are ubiquitous in Today's electronic devices such as smart phones and laptops. Even NASA Rechargeable Uses Batteries in Many Missions to Provide Electrical Power for Survival During Eclipse Periods on Solar-Powred Missions (EG, Low-Earth Orbiting Satellites, International Space Station), and AS A Power Source for Astronaut Suits for Enubling Them to perform Extra Vehicular Activities. Indeed, lithium-ion batteries have also been used in mars moor and rovers.
UNFORTUNATELY, The state-of-the-art lithium-ion batteries are heavy and bulky. Graphite, the soft and flaky matterial in pencil lead, has long been a key component in lithium-ion batteries.
At the microscopic scale, graphite consists of multiple layers of carbon stacked on top of oneother. In a traditional lithium-ion battery, lithium ions zip in and out of the vacant gallery space between these layers in graphite. Although graphite is a very efficient anode, it cannot store much lithium.
Therefore, it Takes a Large Number of Graphite-Based Cells to Provide the Needed Energy for Space Missions Leading to Heavier Battery Packs that must be transported into space. This low capacity of graphite electrodes is also disad further for the use of lithium-ion batteries in electric cars or other battery powered tools.
“Rechargeable Batteries Are important Sources for Providing Electrical Power for Survival During Eclipse Periods on Solar-Powed Missions,” Ramakrishna Podila, An Assistant Professor at Clemson University, Tells Nanowerk. “For Example, The Batteries in The Iss Are Charted Via The Solar Arrays During The Approximataly 45-Minute Period when the arrays are in Direct Sunlight Each Orbit and Are Discharged Asy Power the Station's Loads During the Other 45-Minute Period of Darkness Per Orbit.
A transition to lightweight lithium-ion batteries is to sayly needed. The Integration of Graphite-Based Batteries Into Nasa Missions Or Electric Cars has been extremely limited to beigher weight.
Silicon has ten times high capacity than graphite. Replacing Graphite With Silicon Could Lead to Lighter and Safer Batteries. Although silicon can take on More Lithium Than Graphite, It Tends to Expand About 300 Percent in Volume, Causing the Anode to Become Electrically Insulating and Break Apart. This limits the cycle life of silicon-based lithium batteries to less than 100 cycles.
Reporting Their Findings from a Project Funded by Nasa, Scientists from Clemson Nanomaterials Institute have Recently Discovered A novel 'Sandwiched' Silicon Electrode Structure that can withstand 500 cycles and deliver capacities Three Times Larger Than Graphite.
Their results are published in ACS Applied Materials and Interfaces ("Three-Dimensal Si Anodes With Fast Diffusion, High Capacity, High Rate Capability, and Long Cycle Life").
“We used freestanding sheets made of carbon nanotubes, Called Bucky Papers, for sandwiching silicon nanoparticles. These nanotubes form a quasi-three-diandal structure and hold silicon nanoparticles together Even after 100 cycles and Mitigate Electrical Resistance ARISING FROM Explains Shailendra Chiluwal, A Graduate Student at Cni and the First-Author on the Study.
The sandwiched silicon anode was able to withstand discord rates as high as 4c (at 4c rate, the battery charges fully within 15 minutes). They also show a stable capacity as high as 1650 mAh/g up to 500 cycles. The Team Showed that the diffusion time constant, for li ion transport in and out of the anode, is increased by 150 Times by using Bucky Papers.
“Silicon as the anode in a lithium-ion Battery represents the 'Holy Grail' for Researchers in this Field,” Note Prof. Appeo M. Rao, Who is Director of the Clemson Nanomaterials Institute and the main Investigator on the Nasa Grant. “Carbon nanotubes in Bucky papers are allowable to lithium ions unlim traditional collectors such as copper. This allows bucky papers to enable faster Ion Transport”
The team used extensive Electrochemical Impedance Spectroscopy and ex-Situ Energy Dispersive X-ray analysis to show that carbon Provide Electrical Connections Between Silicon Nanoparticles Even after 100 cycles Unlike Traditional Silicon Electrodes.
"Our Next Goal is to collaborate with Industrial Partners to Translate this Lab-Based Technology to the Marketplace," Notes Podila, corresponding Author of the Study and a Co-Investigator on the Nasa Grant. "We are Thankful to the Nasa and South Carolina Epscor for Granting An Award to Undertake Such Projects Which Would Have Lasting Impact On Space Missions and the Global Energy Landscape. »»