Crystal Chemistry and Electronic Structure of the Metallic Lithium Ion Conductor, LiNiN

Abstract

The layered ternary nitride LiNiN shows an interesting combination of fast Li+ ion diffusion and metallic behavior, properties which suggest potential applications as an electrode material in lithium ion batteries. A detailed investigation of the structure and properties of LiNiN using powder neutron diffraction, ab initio calculations, SQUID magnetometry, and solid-state NMR is described. Variable-temperature neutron diffraction demonstrates that LiNiN forms a variant of the parent Li3N structure in which Li+ ion vacancies are ordered within the [LiN] planes and with Ni exclusively occupying interlayer positions (at 280 K: hexagonal space group Pm2, a = 3.74304(5) A, c = 3.52542(6) A, Z = 1). Calculations suggest that LiNiN is a one-dimensional metal, as a result of the mixed pi- and sigma-bonding interactions between Ni and N along the c-axis. Solid-state 7Li NMR spectra are consistent with both fast Li+ motion and metallic behavior.

Ab initio study on the Li deintercalation in ternary lithium nitridocuprate Li2.5Cu0.5N

“…3 show that there is a remarkable charge polarization between Cu and N atoms, forming both ionic and strong directional bonding between Cu and N atoms. Therefore, the bonding characteristics in the Li 2.5 Cu 0.5 N are both covalent and ionic, showing a significantly different feature from the ionic bonding for Li 3 N. The interaction between Cu and N is also similar to the one between Ni and N in LiNiN, which has been suggested to be a one-dimensional metal [22]. It may also give rise to the brace maintaining effect for the layered structure [19].…”

Lithium Ion Battery Models and Parameter Identification Techniques

“…These methods are more commonly used to design new cells than to characterize the behavior of existing devices. For this reason, they are more often developed for chemical models and can be found in specific electrochemical journals [157,158].…”

Transition Metal (Fe, Co and Ni) Carbide and Nitride Nanomaterials: Structure, Chemical Synthesis and Applications

“…Ternary transition metal nitride with a formula of Li 3− x M x N (M=Co, Ni, Fe), similar to that of Li 3 N which has a layered crystal structure, shows high performance as an anode material . Its layered structure is beneficial to support fast Li‐ion conduction and low transition metal oxidation states . In view these advantages of transition metal nitrides, various ternary metal nitrides have been reported.…”