Structure–Property Relationships for Polyether-Based Electrolytes in the High-Dielectric-Constant Regime
Structure–Property Relationships for Polyether-Based Electrolytes in the High-Dielectric-Constant Regime
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高介电常数状态下聚醚基电解质的结构与性能关系
DOI：
10.1021/acs.macromol.2c00639
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发表时间：
2022
期刊：
影响因子：
5.5
通讯作者：
Lynd, Nathaniel A.
中科院分区：
文献类型：
--
作者：
Pedretti, Benjamin J.;Czarnecki, Natalie J.;Zhu, Congzhi;Imbrogno, Jennifer;Rivers, Frederick;Freeman, Benny D.;Ganesan, Venkat;Lynd, Nathaniel A.
建立聚合物电解质的一般结构-性质关系对于设计改进的材料以推进固态能量存储至关重要。我们报告了聚醚基电解质的介电常数、玻璃化转变温度和离子电导率之间的关系，其中聚醚主体的介电常数在60 °C下在7-35的范围内。聚醚与二（三氟甲基磺酰基）酰亚胺锂混合物的离子电导率在10- 7 ~ 10-3S/cm之间。在这种较高介电常数的情况下，这里定义为介电常数大于聚（环氧乙烷）的聚合物（ca.玻璃化转变温度随着介电常数的增加而增加，而离子电导率则随着介电常数的增加而降低。这些结果补充了最近的低介电常数制度，其中的离子电导率是有限的介电常数和离子解离的报告。在这里探讨的高介电常数制度，链段动力学减慢，由于更强的聚合物-聚合物和聚合物-离子的相互作用，导致在降低的离子电导率和相关的纯聚合物玻璃化转变温度的增加。本研究的聚合物的不同化学结构，沿着过去粗粒度分子动力学模拟的结果，支持这些结论的一般性，并说明识别导致高电导率聚合物电解质设计的单一分子特征的困难。广泛使用的聚（环氧乙烷）代表了低和高介电常数制度之间的接近最佳的平衡。为了改善聚合物电解质的离子电导率限制，单组分聚合物主体不太可能解决离子解离需求与快速链段动力学之间的权衡。
Establishing general structure–property relationships for polymer electrolytes is crucial to enable design of improved materials to advance solid-state energy storage. We report the relationship between dielectric constant, glass transition temperature, and ionic conductivity for polyether-based electrolytes with dielectric constants of the polyether host within the range 7–35 at 60 °C. The ionic conductivities of the polyether and lithium bis(trifluoromethylsulfonyl)imide mixtures ranged from 10–7to 10–3S/cm. In this higher-dielectric-constant regime, here defined as a polymer with a dielectric constant greater than that of poly(ethylene oxide) (ca. 9.0), the glass transition temperature increased with dielectric constant while ionic conductivity decreased. These results complement a recent report on the low-dielectric-constant regime, where the ionic conductivity was limited by the dielectric constant and ion dissociation. In the high-dielectric-constant regime explored here, segmental dynamics are slowed due to stronger polymer–polymer and polymer–ion interactions, resulting in decreased ionic conductivity and associated increase in neat polymer glass transition temperature. The disparate chemical structures of the polymers of this study, along with the results of past coarse-grained molecular dynamics simulations, support the generality of these conclusions and speak to the difficulty of identifying a single molecular characteristic leading to the design of high-conductivity polymer electrolytes. Widely used poly(ethylene oxide) represents a near-optimal balance between the low- and high-dielectric-constant regimes. To improve upon the ionic conductivity limitations of polymer electrolytes, single-component polymer hosts are unlikely to resolve the trade-off between the need for ion dissociation while retaining rapid segmental dynamics.
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影响因子：
3.9
作者：
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通讯作者：
J. Uehara;K. Aramaki
影响因子：
5.2
作者：
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通讯作者：
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影响因子：
3.2
作者：
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含有单离子接枝共聚物电解质的电池的极化
影响因子：
3.9
作者：
Patrick E. Trapa;A. B. Reyes;R. Gupta;A. Mayes;D. Sadoway
通讯作者：
D. Sadoway
影响因子：
3.6
作者：
BERRIDGE, MS;FRANCESCHINI, MP;TEWSON, TJ
通讯作者：
TEWSON, TJ