A highly-stable layered Fe/Mn-based cathode with ultralow strain for advanced sodium-ion batteries. (October 2021)

• Record Type: Journal Article
• Authors: Qi, Rui; Chu, Mihai; Zhao, Wenguang; Chen, Ziwei; Liao, Lei; Zheng, Shisheng; Chen, Xiping; Xie, Lei; Liu, Tongchao; Ren, Yang; Jin, Lei; Amine, Khalil; Pan, Feng; Xiao, Yinguo
• Is Part Of: Nano energy. Volume 88(2021)
• Publication Date: 2021-10
• Subjects: Sodium-ion battery -- Fe- and Mn-based layered oxide cathodes -- Co-substitution strategy -- Solid-solution reaction -- Lattice strain; Nanoscience -- Periodicals; Nanotechnology -- Periodicals; Nanostructured materials -- Periodicals; Power resources -- Technological innovations -- Periodicals; Nanoscience; Nanostructured materials; Nanotechnology; Power resources -- Technological innovations; Periodicals; 621.042
• DOI: 10.1016/j.nanoen.2021.106206
• Languages: English
• ISSNs: 2211-2855

Abstract

Abstract: Sodium-ion batteries (SIBs) with iron- and manganese-based cathode electrodes have exhibited great promise in the grid-scale energy storage systems, on the basis of the satisfactory theoretical capacity, as well as huge abundance, low price and non-toxicity of raw materials. However, the inferior cycle life of cathode materials originating from their poor structural stability remains a formidable challenge towards practical applications. Here, an efficient strategy of improving the structure durability is demonstrated in iron- and manganese-based cathodes by dual heteroatom doping. The as-obtained P2-type Na0.65 Li0.08 Cu0.08 Fe0.24 Mn0.6 O2 cathode delivers superior cyclability (88.2% capacity retention for 500 cycles at 2C), fabulous rate capability (76% capacity retention at 5C compared to 0.1C), and a useable reversible capacity of around 85 mAh g −1 at 0.1C. Through in-depth characterizations, the underlying structure-property relationship is established, revealing that the complete solid-solution reaction during cycling ensures the ultralow volume variation (as small as 0.7%) and excellent electrochemical performance. These results highlight the significance of fabricating a stable host for the design and development of advanced SIBs with long life. Graphical Abstract: ga1 Highlights: A universal and efficient strategy for improving the structure stability in P2-type Fe- and Mn-based cathode is demonstrated by Li/Cu dual-hetero atoms doping. A newly-designed P2-type Na0.65Li0.08Cu0.08Fe0.24Mn0.6O2exhibits superior electrochemical performance (88.2% capacity retentionafter 500 cycles at 2C and 76% capacity retention at 5C compared to 0.1C). Realizinga complete solid-solution reaction is critical to maintain a stable layered structure. Theintrinsic "host rearrangement-lattice strain-electrode" failure relationship in intercalation-type cathodes is constructed.