Mwizerwa Jean Pierre, Zhang Qiang, Han Fudong, Wan Hongli, Cai Liangting, Wang Chunsheng, Yao Xiayin
Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, 315201 Ningbo, P. R. China.
Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, P. R. China.
ACS Appl Mater Interfaces. 2020 Apr 22;12(16):18519-18525. doi: 10.1021/acsami.0c01607. Epub 2020 Apr 7.
All-solid-state lithium-sulfur batteries employing sulfur electrodes and a solid electrolyte at room temperature are still a great challenge owing to the low conductivities of sulfur cathodes. In this work, we report room temperature all-solid-state lithium-sulfur batteries using thin sulfur layer-embedded FeS (FeS@S) microsphere composites as active materials in the FeS@S-LiGePS-Super P cathode electrode. Setting the cut-off voltage between 1.5 and 2.8 V, only lithiation-delithiation reactions between LFeS and FeS and direct reaction between LiS and S will occur, which avoids large volume change of FeS caused by the conversion reaction, leading to the structure integrity of FeS@S. The resultant batteries exhibit excellent rate and cyclic performances, delivering specific capacities of 1120.9, 937.2, 639.7, 517.2, 361.5, and 307.0 mA h g for the FeS@S composite cathode, corresponding to the normalized capacities of 1645.5, 1252.9, 782.5, 700.2, 478.4, and 363.6 mA h g for sulfur at 30, 50, 100, 500, 1000, and 5000 mA g, respectively. Besides, they can retain the normalized capacity of 430.7 mA h g for sulfur at 1000 mA g after 200 cycles at room temperature.
由于硫阴极的低电导率，在室温下采用硫电极和固体电解质的全固态锂硫电池仍然面临巨大挑战。在这项工作中，我们报道了室温全固态锂硫电池，其使用嵌入薄硫层的FeS（FeS@S）微球复合材料作为FeS@S-LiGePS-超级P阴极电极中的活性材料。将截止电压设置在1.5至2.8V之间，仅会发生LFeS与FeS之间的锂化-脱锂反应以及LiS与S之间的直接反应，这避免了由转化反应引起的FeS的大体积变化，从而导致FeS@S的结构完整性。所得电池表现出优异的倍率和循环性能，对于FeS@S复合阴极，其比容量分别为1120.9、937.2、639.7、517.2、361.5和307.0 mA h g，对应于硫在30、50、100、500、1000和5000 mA g时的归一化容量分别为1645.5、1252.9、782.5、700.2、478.4和363.6 mA h g。此外，在室温下以1000 mA g循环200次后，它们对于硫仍可保持430.7 mA h g的归一化容量。
