Premium
Reviving Anode Protection Layer in Na‐O 2 Batteries: Failure Mechanism and Resolving Strategy
Author(s) -
Lin Xiaoting,
Sun Yipeng,
Sun Qian,
Luo Jing,
Zhao Yang,
Zhao Changtai,
Yang Xiaofei,
Wang Changhong,
Huo Hanyu,
Li Ruying,
Sun Xueliang
Publication year - 2021
Publication title -
advanced energy materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 10.08
H-Index - 220
eISSN - 1614-6840
pISSN - 1614-6832
DOI - 10.1002/aenm.202003789
Subject(s) - materials science , anode , layer (electronics) , superoxide , electrolyte , chemical engineering , nanotechnology , energy storage , electrode , chemistry , power (physics) , biochemistry , physics , quantum mechanics , engineering , enzyme
Na‐O 2 batteries are attractive for energy storage due to their high theoretical energy density. In order to alleviate Na dendrite formation, artificial protective coatings have been widely investigated in Na‐metal batteries (NMBs). Although it can be intuitive to expect transferable Na protection methodologies from NMBs to Na‐O 2 batteries, the performance of anode protection coatings in Na‐O 2 batteries remains obscure, because Na‐O 2 batteries undergo a unique reaction mechanism involving superoxide. Here, the effect of superoxide crossover on the polymeric Na protection layer in Na‐O 2 batteries is revealed, and an effective strategy to eliminate the implications of a superoxide‐sensitive protecting layer is proposed. Using polymeric alucone protected Na anode as an example, the alucone layer actually decomposes under superoxide attack and is incapable of facilitating long‐term cycling of Na‐O 2 batteries in sharp contrast to its stable performance in NMBs. By blocking superoxide crossover with solid‐state electrolytes (SSEs), significantly improved Na‐O 2 cell performance is demonstrated, recovering the Na dendrite suppressing effect of the alucone film. Benefiting from the synergistic effect of SSE and alucone layer, Na‐O 2 batteries can achieve a long life of 325 cycles at 0.2 mA cm −2 . This work indicates that the stability of the Na protection layer against superoxide should be taken into serious consideration.