Superior Stable and Long Life Sodium Metal Anodes Achieved by Atomic Layer Deposition

Abstract

Na-metal batteries are considered as the promising alternative candidate for Li-ion battery beneficial from the wide availability and low cost of sodium, high theoretical specific capacity, and high energy density based on the plating/stripping processes and lowest electrochemical potential. For Na-metal batteries, the crucial problem on metallic Na is one of the biggest challenges. Mossy or dendritic growth of Na occurs in the repetitive Na stripping/plating process with an unstable solid electrolyte interphase layer of nonuniform ionic flux, which can not only lead to the low Coulombic efficiency, but also can create short circuit risks, resulting in possible burning or explosion. In this communication, the atomic layer deposition of Al O coating is first demonstrated for the protection of metallic Na anode for Na-metal batteries. By protecting Na foil with ultrathin Al O layer, the dendrites and mossy Na formation have been effectively suppressed and lifetime has been significantly improved. Furthermore, the thickness of protective layer has been further optimized with 25 cycles of Al O layer presenting the best performance over 500 cycles. The novel design of atomic layer deposition protected metal Na anode may bring in new opportunities to the realization of the next-generation high energy-density Na metal batteries.

Deactivating Defects in Graphenes with Al2O3 Nanoclusters to Produce Long‐Life and High‐Rate Sodium‐Ion Batteries

“…Energy Mater. Figure 4c summarizes the elemental contents of the surface of PGM-T and Al 2 O 3 /PGM-5, which shows that Al 2 O 3 / PGM-5 has less sodium and fluorine which mainly originate from the decomposition of NaOTf, [61,63] consistent with the CV results discussed above. Figure 4c summarizes the elemental contents of the surface of PGM-T and Al 2 O 3 /PGM-5, which shows that Al 2 O 3 / PGM-5 has less sodium and fluorine which mainly originate from the decomposition of NaOTf, [61,63] consistent with the CV results discussed above.…”

Robust Metallic Lithium Anode Protection by the Molecular‐Layer‐Deposition Technique

“…In their results, the ALD Al 2 O 3 ‐protected Li can prevent Li metal corrosion in electrolyte and reduce the dendrite growth as well, which further enhances electrochemical performance with elevated capacity and longer lifetimes. Very recently, our group also successfully demonstrated the protection of Na metal anode using ALD Al 2 O 3 , yielding extended life time and reduced growth of parasitic sodium dendrites . Molecular layer deposition (MLD), as an analogy of ALD, can be employed to produce pure polymeric thin films or inorganic–organic hybrid thin films, which can hold many advantages such, as lower growth temperatures, tunable thermal stability, and improved mechanical properties .…”

High Capacity, Dendrite‐Free Growth, and Minimum Volume Change Na Metal Anode

“…These features make ALD an ideal technique for Na anode protection . Recently, both our group and Hu et al have successfully demonstrated the application of ALD Al 2 O 3 coating layers for the enhancement of electrochemical stability of Na metal anode and suppressed dendrite growth with prolong cycling life time in carbonate and ether based electrolyte systems, respectively . Furthermore, our group first reported the use of inorganic–organic coating (alucone) via molecular layer deposition as a protective layer for metallic Na anode .…”