Tethered Molecular Sorbents: Enabling Metal-Sulfur Battery Cathodes
Tethered Molecular Sorbents: Enabling Metal-Sulfur Battery Cathodes
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DOI：
10.1002/aenm.201400390
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发表时间：
2014-12-09
影响因子：
27.8
通讯作者：
Archer, Lynden A.
中科院分区：
文献类型：
--
作者：
Ma, Lin;Zhuang, Houlong;Archer, Lynden A.
一种在阴极使用硫和金属（例如，Li、Na、Mg或Al）提供了可能最有希望的途径，以获得能够具有高电荷存储容量的固态可再充电电化学存储装置。应当理解，在电解质中的溶解和长链多硫化锂（Li 2Sx，2 < x < 8）形式的硫的损失阻碍了这些装置中研究最多的可再充电Li-S电池的开发。开始与密度泛函计算的结构和相互作用的一个通用的锂多硫化物物种与含腈的分子，它表明，它是可能的设计富含腈的分子吸附剂，锚到其他组件中的硫阴极，并发挥足够高的结合亲和力，以限制其损失的电解质的Li 2 Sx。发现基于胺和咪唑鎓氯化物的吸附剂对长链Li 2Sx的溶解存在障碍，并且将少至2重量%的这些分子引入物理硫-碳共混物导致Li-S电池阴极在高和低充电/放电速率下表现出稳定的长期循环行为。
A rechargeable battery that uses sulfur at the cathode and a metal (e.g., Li, Na, Mg, or Al) at the anode provides perhaps the most promising path to a solid-state, rechargeable electrochemical storage device capable of high charge storage capacity. It is understood that solubilization in the electrolyte and loss of sulfur in the form of long-chain lithium polysulfi des (Li2Sx, 2 < x < 8) has hindered development of the most studied of these devices, the rechargeable Li-S battery. Beginning with density-functional calculations of the structure and interactions of a generic lithium polysulfi de species with nitrile containing molecules, it is shown that it is possible to design nitrile-rich molecular sorbents that anchor to other components in a sulfur cathode and which exert high-enough binding affinity to Li2Sx to limit its loss to the electrolyte. It is found that sorbents based on amines and imidazolium chloride present barriers to dissolution of long-chain Li2Sx and that introduction of as little as 2 wt% of these molecules to a physical sulfur-carbon blend leads to Li-S battery cathodes that exhibit stable long-term cycling behaviors at high and low charge/discharge rates.