The effect of surface area on the electrochemical properties and thermal stability of Li[Ni 0.2 Li 0.2 Mn 0.6 ]O 2 powders was characterized using a charge/discharge cycler and DSC (Differential Scanning Calorimeter). The surface area of the samples was successfully controlled from *4.0 to *11.7 m 2 g -1 by changing the molar ratio of the nitrate/ acetate sources and adding an organic solvent such as acetic acid or glucose. The discharge capacity and rate capability was almost linearly increased with increase in surface area of the sample powder. A sample with a large surface area of 9.6-11.7 m 2 g -1 delivered a high discharge capacity of *250 mAh g -1 at a 0.2 C rate and maintained 62-63% of its capacity at a 6 C rate versus a 0.2 C rate. According to the DSC analysis, heat generation by thermal reaction between the charged electrode and electrolyte was not critically dependent on the surface area. Instead, it was closely related to the type of organic solvent employed in the fabrication process of the powder.
The surface of Li[Ni0.8Co0.15Al0.05]O2 cathode particle was modified by lanthanum based oxide to improve electrochemical property and thermal stability. The XRD pattern of surface layer was indexed with that of La4NiLiO8. The discharge capacity of modified electrode was higher than that of pristine sample, specially at fast charge-discharge rate and high cut-off voltage. In the DSC profile of the charged sample, the generation of heat by exothermic reaction was decreased by surface modification. Such enhancement may by attributed to the presence of stable lanthanum based oxide, which effectively suppressd the reaction between electrode and electrolyte on the surface of Li[Ni0.8Co0.15Al0.05]O2 electrode.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.