High-performance all-solid-state lithium-sulfur batteries with sulfur/carbon nano-hybrids in a composite cathode
High-performance all-solid-state lithium-sulfur batteries with sulfur/carbon nano-hybrids in a composite cathode
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复合阴极中具有硫/碳纳米杂化物的高性能全固态锂硫电池
DOI：
10.1039/c8ta08420c
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发表时间：
2018
影响因子：
11.9
通讯作者：
Shen Yang
中科院分区：
文献类型：
--
作者：
Zhang Yibo;Liu Ting;Zhang Qinghua;Zhang Xue;Wang Shuo;Wang Xinzhi;Li Liangliang;Fan Li-Zhen;Nan Ce Wen;Shen Yang
穿梭效应对锂硫(Li-S)电池的安全性和循环寿命提出了极大的挑战。一个有希望的解决方案是用固体电解质取代液体电解质。然而，固体电解质的低本征电导率导致锂离子和电子在复合阴极中的缓慢迁移，影响了全固态锂S电池的倍率和循环性能。采用溶剂交换法将硫磺纳米颗粒与不同尺寸的碳物种(如0D碳纳米颗粒、一维多壁碳纳米管(MWCNTs)和超长气相生长碳纤维(VGCF))熔融形成纳米杂化材料，然后在复合阴极中组装成导电网络。零维和一维纳米杂化材料分别促进了电子的短程和长程迁移。与硫纳米颗粒融合后，导电网络本身可以作为含硫基质，缩短锂离子的扩散路径。这些有利的特性使得复合阴极的电导率/离子导电性和高硫负载量大大提高。用这些复合正极组装的全固态锂S电池(ASSLSB)迄今表现出最高的高倍率循环容量和室温保持率。放电容量为1140.9 mA h g−1，放电电流为0.176 mA cm−2(约0.1C)，循环400次后容量保持率为100%。经过1000次循环后，电池在0.44 mA cm−2(约0.25℃)下仍具有834.3 mA h g−1的高放电容量。
The shuttle effect poses great challenges to the safety and cycle lifetime of lithium–sulfur (Li–S) batteries. One promising resolution is to substitute liquid electrolytes with solid electrolytes. However, the low intrinsic electrical conductivity of solid electrolytes results in the slow migration of lithium ions and electrons in the composite cathodes and compromises the rate and cycling performance of the all-solid-state Li–S cells. Here, sulfur nanoparticles are fused with carbon species of different dimensions (e.g., 0D carbon nanoparticles, 1D multi-wall carbon nanotubes (MWCNTs) and ultra-long vapor grown carbon fibers (VGCF)) to form nanohybrids by the solvent exchange method, and are then assembled into electrically conducting networks in the composite cathode. The 0D and 1D nanohybrids facilitate the short and long-range migration of electrons, respectively. Fused with sulfur nanoparticles, the conducting networks themselves could act as sulfur-bearing matrixes and shorten the diffusion path of lithium ions. These favorable features give rise to much-enhanced electric/ionic conductivity and high sulfur loading of the composite cathode. The all-solid-state Li–S batteries (ASSLSBs) assembled with these composite cathodes have so far exhibited the highest high-rate cycling capacity and retention at room temperature. A discharge capacity of 1140.9 mA h g−1 at 0.176 mA cm−2 (about 0.1C) was achieved with a capacity retention of 100% after 400 cycles. After 1000 cycles, the battery still showed a high discharge capacity of 834.3 mA h g−1 at 0.44 mA cm−2 (about 0.25C).