Tin Nitride Thin Films as Negative Electrode Material for Lithium-Ion Solid-State Batteries

Abstract

Tin nitride thin films have been reported as promising negative electrode materials for lithium-ion solid-state microbatteries. However, the reaction mechanism of this material has not been thoroughly investigated in the literature. To that purpose, a detailed electrochemical investigation of radio-frequency-sputtered tin nitride electrodes of two compositions (1:1 and 3:4) is presented for several layer thicknesses. The as-prepared thin films have been characterized by Rutherford backscattering spectrometry, inductively coupled plasma optical emission spectrometry, scanning electron microscopy, X-ray diffraction, and transmission electron microscopy. The electrochemical results point out that the conversion mechanism of tin nitride most probably differs from the conversion mechanism usually observed for other oxide and nitride conversion electrode materials. The electrochemical data show that more than 6 Li per Sn atom can be reversibly exchanged by this material, whereas only about 4 are expected. Moreover, the electrochemical performance of the material is discussed, such as electrode cycle life, and a method for improving the cycle life is presented. Finally, thicker films have been characterized by Mössbauer spectroscopy. This technique opens a new route toward determining the conversion reaction mechanism of this promising electrode material.

All‐Solid‐State Lithium‐Ion Microbatteries: A Review of Various Three‐Dimensional Concepts

“…This effect was attributed to the formation of the Li 2 O framework that stabilizes the shrinking and expanding metal particles. [ 158 ] Also several nitrides were reported to undergo a similar alloying storage reaction, such as SnN x , [ 159 ] Zn 3 N 2 [ 160 ] and Ge 3 N 4 . [ 161 ] …”

Evaluation of nanocrystalline Sn3N4derived from ammonolysis of Sn(NEt2)4as a negative electrode material for Li-ion and Na-ion batteries

“…The electrochemical performance of Sn 3 N 4 electrodes in lithium cells has only previously been investigated using samples in thin lm form. 28,29 Hence, the Sn 3 N 4 /acetylene black/ sodium alginate electrodes described above were also examined in lithium half cells with a standard LiPF 6 /EC/DMC electrolyte. As in the sodium cells reduction and alloying could be envisaged as shown in the following equations, based on which the theoretical capacity is 1560 mA h g À1 and charge/discharge at 100 mA g À1 is equivalent to a C-rate of C/15.6.…”

“…Baggetto et al observed similar capacity losses from thin lm electrodes, but were able to extend the lifetime of the electrodes by limiting the potential range over which they cycled. 29 In order to understand the charge storage mechanism of Sn 3 N 4 in Li half-cells, ex situ XRD data were collected (Fig. 7).…”

“…28 Baggetto et al later found that more than 6 Li atoms per Sn atom could be stored and argued that conversion and alloying must both be working reversibly, with retention of a volumetric capacity of 700 mA h cm À2 mm À1 possible over 50 cycles and the possibility of extending this to 100 cycles if only $80% of this capacity was utilised. 29 Herein we produce nanocrystalline Sn 3 N 4 by ammonolysis of a tin(IV) dialkylamide. We examine its suitability as a sodiumion or lithium-ion negative electrode material in conventional half cells using composite electrodes with carbon black and a binder.…”

Electrochemically Fabricated Polypyrrole–Cobalt–Oxygen Coordination Complex as High‐Performance Lithium‐Storage Materials

“…3Co 0 + 4 Li 2 O. Lithium storage by means of conversion reactions has also been observed in other transition metal compounds, such as sulfides [8] and nitrides. [9] Although the cycling performances of these compounds are not satisfactory at present, such reaction provides highly active transition metal atoms that might interact with PPy and form PPymetal complexes.…”