A macrocyclic amine-based electrolyte for lithium–sulfur batteries: Li ion encapsulation regulates electrode performance
A macrocyclic amine-based electrolyte for lithium–sulfur batteries: Li ion encapsulation regulates electrode performance
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DOI：
10.1063/5.0159107
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发表时间：
2023-10
影响因子：
15
通讯作者：
Ji Zhou;Wen Gong;Xiaodong Meng;Jiawen Zhang;Xueqin Zhou;Shang Chen;C. Bielawski;Jianxin Geng
中科院分区：
文献类型：
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作者：
Ji Zhou;Wen Gong;Xiaodong Meng;Jiawen Zhang;Xueqin Zhou;Shang Chen;C. Bielawski;Jianxin Geng
锂硫（Li-S）电池的广泛使用受到缓慢阴极动力学、穿梭效应和阳极上的枝晶生长的阻碍。我们表明，这些挑战可以通过取代线性醚（即，1，2-二甲氧基乙烷）与大环胺1，4，7，10-四甲基-1，4，7，10-四氮杂环十二烷（TMTAC）。理论研究和实验数据表明，TMTAC的腔匹配的锂离子，形成一个强大的溶剂化结构。这种溶剂化结构不仅导致Li 2S在阴极上的3D沉积，这是导致Li 2S成核和分解的过电位降低的原因，而且还抑制了阳极上的Li枝晶生长。此外，多硫化物的穿梭效应被有效地抑制，因为TMTAC基电解质中游离TMTAC的量显著减少。因此，用基于TMTAC的电解质制备的纽扣型电池在所有关键器件参数方面都表现出出色的性能指标。此外，袋型电池可以用高硫负载（例如，3.43 mgcm-2）和低电解质与硫的比率（例如，6.16μl mg−1），同时保持高面积比容量（3.38 mA h cm−2）。这项工作表明，在能量存储设备中的关键离子的有效溶剂化是至关重要的，以实现峰值性能。
The widespread use of lithium–sulfur (Li–S) batteries is hindered by slow cathode kinetics, the shuttle effect, and dendrite growth on the anode. We show that these challenges can be overcome by replacing a linear ether (i.e., 1,2-dimethoxyethane) in commonly used electrolytes with a macrocyclic amine, 1,4,7,10-tetramethyl-1,4,7,10-tetraazacyclododecane (TMTAC). Theoretical studies and experimental data indicate that the cavity of TMTAC matches a Li ion to form a robust solvation structure. Such a solvation structure not only leads to 3D deposition of Li2S on the cathode, which is responsible to the reduced overpotentials of Li2S nucleation and decomposition, but also suppresses Li dendrite growth on the anode. Moreover, the shuttle effect of polysulfides is effectively suppressed as the quantity of free TMTAC in the TMTAC-based electrolyte is substantially reduced. As a result, coin-type cells prepared with TMTAC-based electrolytes exhibit outstanding performance metrics for all key device parameters. Furthermore, pouch-type cells can be prepared with high sulfur loadings (e.g., 3.43 mg cm−2) and a low electrolyte to sulfur ratio (e.g., 6.16 μl mg−1) while maintaining a high areal specific capacity (3.38 mA h cm−2). This work demonstrates that the effective solvation of critical ions in energy storage devices is paramount to achieving peak performance.