Energy Storage

Energy Storage Lithium ion battery Lithium-ion batteries consist of 2 electrodes and an electrolyte. The electrodes are oppositely charged and the electrolyte allows the ions to travel between each electrode for charging and discharging. Carbon nanotubes are able to replace the traditional material used for the cathode in these batteries, as they contain many functional groups on their surface, which lets them store a large amount of lithium ions. Using carbon materials for the cathode speeds up the lithium storage reaction considerably, therefore they can deliver much more power. Electrostatic interactions in the battery causes the nanotubes to take a ‘porous’ structure, leaving many exposed surfaces for reactions to take place; nanotubes usually clump together without electrostatic forces, which doesn’t leave a lot of surface area. Nanotube batteries are able to output 10 times the power of a standard lithium-ion battery and keep a much better stability over time; after 1000 charging and discharging cycles there has been no change detected in tested batteries. Hydrogen Researchers have come up with a structure using carbon nanotubes that can store vast amounts of hydrogen. The nanotubes are arranged in a sponge like structure, where they are crossed over each other in a 3D grid structure. A common method of packing nanotubes is by keeping them parallel to each other, where the entire edges of the tubes touch each other; in the grid structure, there are only specific points of contact and this was found to absorb a substantial amount more hydrogen than the parallel structure. Only a model of the sponge structure has been made, because it is very difficult to make an ordered 3D network using single wall carbon nanotubes.