The novel compound Na2-x(CB11H12)x(B12H12)1-x shows a fast ionic Na conductivity of 2 mS cm−1 at room temperature, reaching the superionic regime above 333 K. A low activation energy of 314 meV, in a thermodynamically and electrochemically stable structure, suggest its usage as a potential solid electrolyte in future all-solid Na-ion batteries. Density functional theory simulations indicate the heterovalent anionic mixing to be the responsible in stabilizing a bcc structure, which allows a facile Na+ diffusion already at room temperature. Cyclic voltammetry measurement with a tailored setup for solid-state electrolytes reveals a wide operating window (up to 4.1 V vs. Na+/Na). The symmetrical cell featuring Na–Sn alloy-based electrodes shows reversible Na+ shuttling with limited polarization after more than 700 operating hours.
A mixed anion hydroborate/carba-hydroborate as a room temperature Na-ion solid electrolyte / Brighi, M.; Murgia, F.; Lodziana, Z.; Schouwink, P.; Wolczyk, A.; Cerny, R.. - In: JOURNAL OF POWER SOURCES. - ISSN 0378-7753. - 404:(2018), pp. 7-12. [10.1016/j.jpowsour.2018.09.085]
A mixed anion hydroborate/carba-hydroborate as a room temperature Na-ion solid electrolyte
Murgia F.;Cerny R.
2018-01-01
Abstract
The novel compound Na2-x(CB11H12)x(B12H12)1-x shows a fast ionic Na conductivity of 2 mS cm−1 at room temperature, reaching the superionic regime above 333 K. A low activation energy of 314 meV, in a thermodynamically and electrochemically stable structure, suggest its usage as a potential solid electrolyte in future all-solid Na-ion batteries. Density functional theory simulations indicate the heterovalent anionic mixing to be the responsible in stabilizing a bcc structure, which allows a facile Na+ diffusion already at room temperature. Cyclic voltammetry measurement with a tailored setup for solid-state electrolytes reveals a wide operating window (up to 4.1 V vs. Na+/Na). The symmetrical cell featuring Na–Sn alloy-based electrodes shows reversible Na+ shuttling with limited polarization after more than 700 operating hours.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.