1. CARBON NANOTUBE TECHNOLOGY IN ELECTRIC VEHICLE BATTERIES CHRIS SIAK AND BEN YEH 1.Graphene carbon sheets intertwined with themselves by covalent bonds 2.Increased strength, tenacity, flexibility and conductivity- flow of electrons 3. If electrons obtain a certain energy higher than the electrons of the carbon nanotube tube, the carbon nanotube will conduct electricity. 1.If incorporated in electrodes (where electrons flow to and from), can increase flow of electrons, giving less resistance in a battery Carbon Nanotubes Very powerful capacitors that store and release energy They provide extra power to circuits when needed Or, can power circuit independently Can be used with carbon nanotubes to create an extremely efficient power source Supercapacitors Replace capacitor’s metal-oxide electrodes with carbon nanotubes for the electrons to travel across Offers low current resistance, high power and energy densities, and an increased capacitance Can be attributed to carbon nanotubes’ : Good conductivity of electricity High abundance and low price Low weight Carbon nanotube-based supercapacitors also have high power-to-weight ratios, energy efficiencies, as well as high- temperature performance Data: Stores and releases energy up to 10 times faster than current electric vehicle batteries (lithium-ion) Furthermore, adding graphene flake composite to the carbon nanotubes can increase capacitance levels threefold to 100 Farads per gram This researched technology maximizes both energy and power densities, while typically-used lithium-ion batteries only maximize energy density (as shown below) Supercapacitors + Carbon Nanotubes Application in Electric Vehicle Batteries This graph depicts how carbon nanotube-based supercapacitors are more efficient alternatives to today’s lithium ion batteries [11] Importance, Impact, and Pros/Cons 1.Implementing these powerful supercapacitors into the lithium-ion batteries that power electric vehicle can make the vehicles drive further on a single charge, and have power efficiencies more comparable to today’s gas- powered cars 1.Statistically, consider driving range increasing to about 500km, more than double the current limit of an electric car 2.Application of this technology in specifically the lithium- ion batteries that power EV’s is useful due to the carbon nanotubes’ ability to store Li-ions on its surface 1.Electric cars may become even more “sustainable” than they are currently, and more “sustainable” than today’s gas-powered cars 1.“Sustainability” in this case includes the effectiveness and efficiency of power and energy density, cost, and environmental impact 2.Technological and societal pros and cons implementing nanotube-based supercapacitors in EV batteries are outlined in the table below: 3.Carbon nanotube based supercapacitors have both sustainable and not-so-sustainable qualities and must be further researched and developed to maximize sustainability for the public market. Chemical Vapor Deposition 1.Process which carbon nanotubes are made 2.Passing carbon-containing gas over a hot transition metal catalytic nanoparticle-makes one single carbon nanotube 3.Characteristics are affected by the geometry of the catalytic metal 4.No clear relationship between characteristic properties of carbon nanotubes and its geometry of the catalytic metal 5.However, we are able to determine that an increase in carbon nanotubes… 1.Increases capacitance 2.Increases efficiency of battery This is what a carbon nanotube looks with its hexagonal graphene structure. Notice how the empty space allows for electrons to flow like a wave through the carbon nanotube The graph shows a direct relationship that the more carbon nanotubes are used, the higher the capacitance. As a result, using carbon nanotubes in a battery increases the battery’s capacitance. PROSCONS Cutting down on the 30 percent of worldwide greenhouse gases that come from gas-powered cars (including nitrous oxides, volatile organic carbons, and carbon monoxide) Eventual decay of batteries in landfill, which can pollute water runoff and soil Process of building the batteries can be difficult and inefficient in itself Electric vehicles will still have a considerably more expensive up-front cost when compared to gas-powered cars Conservation of non- renewable fossil fuels Increased marketability for electric vehicles References: J. T. Sánchez. (2012, April). “Applications to the Energy Sector: Rechargeable Batteries and Supercapacitors.” Uniersidad Pontificia Comillas. (Lecture). Kidd, Rob. “QUT leading the charge for panel-powered cars.” (2014 Nov. 06). Queensland University of Technology. (online article). https://www.qut.edu.au/news/news?news-id=81659https://www.qut.edu.au/news/news?news-id=81659 A. Rana, A, Chaudhary, P Karandikar. (24 Aug. 2013). “Effect of Carbon Nanotubes on the Capacitance of an Ultra-Capacitor.” Global Humanitarian Technology Conference. (online article). DOI: 10.1109/GHTC-SAS.2013.6629901. T. Seager, R. Raffaelle, and B. Landi. (22 May 2008). “Sources of Variability and Uncertainty in LCA of Single Wall Carbon Nanotubes for Li-Ion Batteries in Electric Vehicles.” Electronics and the Environment. (online article). DOI: 10.1109/ISEE.2008.4562878. N. Sugumaran, P. Everill, et al. “Lead acid battery performance and cycle life increase through addition of discrete carbon nanotubes to both electrodes.” (2014). Journal of Power Sources. (online article). DOI: 10.101/j.powsour.2014.12.117 D.P Jenicek, A. McCarthy, et al. (2014). “Modifying the characteristics of carbon nanotubes grown on metallic substrates for ultracapacitor applications.” Journal of Applied Physics. (online article). DOI: 10.1063/1.4880197 J. Liu, F. Mirri, et al. “High performance all-carbon thin film supercapacitors.” (2015 Jan. 15). Journal of Power Sources. (online article). “Batteries for Hybrid and Plug-In Vehicles.” (2015, January 9). U.S Department of Energy. (online article). Available: http://www.afdc.energy.gov/vehicles/electric_batt eries.htmlhttp://www.afdc.energy.gov/vehicles/electric_batt eries.html