Sodium-ion batteries are promising for large-scale energy storage due to sodium's low cost and infinite abundance. The most popular cathodes for sodium-ion batteries, i.e., the layered sodium-containing oxides, us...Sodium-ion batteries are promising for large-scale energy storage due to sodium's low cost and infinite abundance. The most popular cathodes for sodium-ion batteries, i.e., the layered sodium-containing oxides, usually exhibit reversible host rearrangement between P-type and O-type stacking upon charge/discharge. Herein we demonstrate that such host rearrangement is unfavorable and can be suppressed by introducing transition-metal ions into sodium layers. The electrode with stabilized P3-type stacking delivers superior rate capability, high energy efficiency, and excellent cycling performance. Owing to the cation-mixing nature, it performs the lowest lattice strain among all reported cathodes for sodium-ion batteries. Our findings highlight the significance of a stable host for sodium-ion storage and moreover underline the fundamental distinction in material design strategy between lithium-and sodium-ion batteries.展开更多
基金The financial support from the National Basic Research Program of China(2014CB932300)Natural Science Foundation of Jiangsu Province of China(BK20170630)+1 种基金NSF of China(21633003 and 51602144)sponsored by the JST-CREST ‘‘Phase Interface Science for Highly Efficient Energy Utilization",JST(Japan)
文摘Sodium-ion batteries are promising for large-scale energy storage due to sodium's low cost and infinite abundance. The most popular cathodes for sodium-ion batteries, i.e., the layered sodium-containing oxides, usually exhibit reversible host rearrangement between P-type and O-type stacking upon charge/discharge. Herein we demonstrate that such host rearrangement is unfavorable and can be suppressed by introducing transition-metal ions into sodium layers. The electrode with stabilized P3-type stacking delivers superior rate capability, high energy efficiency, and excellent cycling performance. Owing to the cation-mixing nature, it performs the lowest lattice strain among all reported cathodes for sodium-ion batteries. Our findings highlight the significance of a stable host for sodium-ion storage and moreover underline the fundamental distinction in material design strategy between lithium-and sodium-ion batteries.