| Popis: |
An energy economy based on renewable technologies will need energy storage capabilities on an enormous scale to combat power generation fluctuations. To provide the amount of energy storage that will be needed, low-cost batteries made with earth abundant elements will be a necessity for grid-scale storage. Furthermore, these batteries should have chemistries that can guarantee safety for the users and be non-toxic to the environment. Aqueous sodium-ion batteries (ASIB) are one option that can fill these requirements while also promising long lifetimes. There has been considerable effort put forth into the development of sodium ion intercalation batteries that combine sodium and lithium chemistries. Sodium titanium phosphate (NTP) as the anode and lithium manganese oxide (LMO) as the cathode are a commonly researched pairing. While the LMO is only capable of cycling the lithium ions in solution, the NTP is capable of cycling both sodium and lithium ions, although to different degrees at different potentials. This talk will look into the conditions at which the different ions cycle into the NTP, how this can turn sodium titanium phosphate into lithium titanium phosphate (LTP), as well as the effect that lithium insertion into NTP has on the LMO cathode. This will be done by tracking ionic concentrations in laboratory scale batteries at different states-of-charge (SOC’s) and states-of-health (SOH) and correlating to differential capacity curves. Comparisons will be made against ex-situ cyclic voltammetry studies for NTP and LTP when these materials are exposed to different ratios of Li+ and Na+ in solution. |
