Nanobatteries
Nanobatteries are fabricated batteries employing technology at the nanoscale, particles that measure less than 100 nanometers or 10−7 meters.
[4] Traditional lithium-ion battery technology uses active materials, such as cobalt-oxide or manganese oxide, with particles that range in size between 5 and 20 micrometers (5000 and 20000 nanometers – over 100 times nanoscale).
It is hoped that nano-engineering will improve many of the shortcomings of present battery technology, such as volume expansion and power density.
[8] To improve a battery technology, cycling ability and energy and power density must be maximized and volume expansion must be minimized.
Lithium iron phosphate electrodes are being researched for potential applications to grid energy storage.
[8] In Li-ion batteries, the SEI is necessary for thermal stability, but hinders the flow of lithium ions from the electrode to the electrolyte.
[18] Titanium oxides are another anode material that have been researched for their applications to electric vehicles and grid energy storage.
[8][19] Silicon-based anodes have high reaction rates with the electrolyte, low volumetric capacity and an extremely large volume expansion during cycling.
[15] Porous graphene created good pore channels for the diffusion of lithium ions and prevented the buildup of LiFePO4 particles.
Problems associated with lithium sulphur batteries include dissolution of the intermediate in the electrolyte, large volume expansion and poor electrical conductivity.
[17] Graphene has been mixed with sulphur at the cathode in an attempt to improve the capacity, stability and conductivity of these batteries.
Zhu et al. are also mapping the intercalation of lithium ions at the nanoscale using scanning probe microscopy.
[25] Their experimental data for LiFePO4 – FePO4 suggested the movement of Li-ions in a curved path rather than a linear straight jump within the electrolyte.
Lee et al. has studied and determined the proper intercalation mechanism for rechargeable zinc batteries.
Applications for stretchable electronics include energy storage devices and solar cells.
[28] Researchers at the University of California, Los Angeles have successfully developed a "nanotube ink" for manufacturing flexible batteries using printed electronics techniques.
[18] A network of carbon nanotubes has been used as a form of electronically conducting nanowires in the cathode of a zinc-carbon battery.
This technology replaces charge collectors like metal sheets or films with a random array of carbon nanotubes.
[29] Technology like this is applicable to solar cells, supercapacitors, light-emitting diodes and smart radio frequency identification (RFID) tags.
By using nanomaterial, Toshiba has increased the surface area of the lithium and widened the bottleneck, allowing the particles to pass through the liquid and recharge the battery more quickly.
The advance that Altair claims to have made is in the optimization of nano-structured lithium titanate spinel oxide (LTO).
U.S. Photonics is in the process of developing a nanobattery utilizing "environmentally friendly" nanomaterials for both the anode and cathode as well as arrays of individual nano-sized cell containers for the solid polymer electrolyte.
U.S. Photonics has received a National Science Foundation SBIR phase I grant for development of nanobattery technology.
