Li Wei, Lai Qingsong, Gao Xuan-Wen, Yang Dongrun, Wen Lei, Liu Zhaomeng, Luo Wen-Bin
Institute for Energy Electrochemistry and Urban Mines Metallurgy, School of Metallurgy, Northeastern University, Liaoning, 110819, China.
Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), College of Chemistry, Nankai University, Tianjin, 300071, China.
Small. 2024 Dec;20(50):e2406453. doi: 10.1002/smll.202406453. Epub 2024 Oct 2.
The layer-structured oxide cathode for sodium-ion batteries has attracted a widespread attention due to the unique redox properties and the anionic redox activity providing additional capacity. Nevertheless, such excessive oxygen redox reactions will lead to irreversible oxygen release, resulting in a rapid deterioration of the cycling stability. Herein, sulfur ion is successfully introduced to the O3-NaNiMnCuTiWO material through high-temperature quenching, thereby developing a novel NaS-modified O3/P2-NaNiMnCuTiWO composite with extended cycling life. The S is analyzed for the ability to enhance the reversibility of oxidation-reduction reactions under high voltage and suppress the loss of lattice oxygen during cycling. The stable S─O covalent bonds are found to inhibit the oxygen generation and release within the structure. Benefiting from these improvements, the Na₂S-modified O3/P2-NaNiMnCuTiWO exhibited a high reversible capacity of 173.1 mA h g over a wide voltage range of 1.5-4.3 V under test conditions at 0.1 C and 81.5% capacity retention after 120 cycles at 1 C. The Na₂S-modified O3/P2-NaNiMnCuTiWO demonstrates the excellent rate capability with the reversible capacities of 173.1,137.0,114.7,96.7, and 80.1 mA h g at 0.1, 0.2, 0.5, 1, and 2 C.
用于钠离子电池的层状结构氧化物阴极因其独特的氧化还原特性和提供额外容量的阴离子氧化还原活性而受到广泛关注。然而，这种过度的氧氧化还原反应会导致不可逆的氧释放，从而导致循环稳定性迅速恶化。在此，通过高温淬火成功地将硫离子引入到O3-NaNiMnCuTiWO材料中，从而开发出一种具有延长循环寿命的新型NaS改性O3/P2-NaNiMnCuTiWO复合材料。分析了S在高压下增强氧化还原反应可逆性以及抑制循环过程中晶格氧损失的能力。发现稳定的S─O共价键可抑制结构内的氧生成和释放。受益于这些改进，Na₂S改性的O3/P2-NaNiMnCuTiWO在0.1 C的测试条件下，在1.5-4.3 V的宽电压范围内表现出173.1 mA h g的高可逆容量，在1 C下循环120次后容量保持率为81.5%。Na₂S改性的O3/P2-NaNiMnCuTiWO在0.1、0.2、0.5、1和2 C下的可逆容量分别为173.1、137.0、114.7、96.7和80.1 mA h g，显示出优异的倍率性能。
