Interpenetrating Network-Based Hybrid Solid and Gel Electrolytes for High Voltage Lithium Metal Batteries
Interpenetrating Network-Based Hybrid Solid and Gel Electrolytes for High Voltage Lithium Metal Batteries
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DOI：
10.1021/acsaem.1c00451
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发表时间：
2021-06
期刊：
影响因子：
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通讯作者：
Yongwei Zheng;Xiaowei Li;William R. Fullerton;Qiang Qian;Mingwei Shang;J. Niu;Christopher Y. Li
中科院分区：
文献类型：
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作者：
Yongwei Zheng;Xiaowei Li;William R. Fullerton;Qiang Qian;Mingwei Shang;J. Niu;Christopher Y. Li
与传统的液态电解液锂离子电池相比，固态金属锂电池具有更高的安全性和更高的能量密度，是未来理想的能源供应选择。基于聚环氧乙烷(PEO)的网络型固体聚合物电解质(SPE)具有成本低、化学通用性好、抗锂树枝晶性能好、器件可循环性好等优点，近年来在该领域受到越来越多的关注。然而，较低的阳极稳定性使该系统与锂镍锰钴氧化物等高压阴极不兼容。在这项工作中，我们通过引入互穿网络(IPN)来解决这个问题，该网络由含有PEO的一级网络SPE和线性聚丙烯腈(PAN)二级网络组成。这些IPN-SPE的化学和结构性质使我们能够通过仅加入2wt%的PAN来显著提高SPE的氧化稳定性，从4.1V提高到5.1V以上。IPN网络既可以作为固体电解质，也可以作为基质形成凝胶电解质。在基于IPN-SPE、锂金属正极和LiNi0.6Mn0.2Co0.2O2正极的SSLMBs中，在90°C下获得了超过150mAhg-1的容量和良好的循环性能。通过向IPN-SPE中渗透二甘氨基液体电解质，形成了具有优异的电化学性能和较高的室温电导率的凝胶电解质。使用这种电解液的LMBs的容量超过170mAHg-1，具有良好的库仑效率和循环稳定性。我们的研究表明，基于IPN的SPE有望解决高压二次电池的挑战。
Solid-state lithium metal batteries (SSLMBs) are a desired future energy supply choice because of their improved safety and higher energy density compared with traditional liquid electrolyte-based lithium ion batteries. Poly(ethylene oxide) (PEO)-based network solid polymer electrolytes (SPEs) have recently attracted increasing attention in the research field due to their low cost, chemical versatility, excellent lithium dendrite resistance, and good device cyclability. However, the low anodic stability renders this system incompatible with high voltage cathodes, such as lithium nickel manganese cobalt oxides. In this work, we tackled this problem by introducing an interpenetrating network (IPN), which consisted of a primary PEO-contained network SPE and a linear poly(acrylonitrile) (PAN) secondary network. The chemical and architectural nature of these IPN-SPEs allowed us to significantly increase the oxidative stability of the SPEs from 4.1 V to over 5.1 V by incorporating only 2 wt % of PAN. The IPN network can be used as both the SPE as well as the host to form gel electrolytes. In SSLMBs based on the IPN-SPEs, lithium metal anodes, and LiNi0.6Mn0.2Co0.2O2cathodes, a capacity of over 150 mAh g–1was achieved at 90 °C with excellent cyclability. By infiltrating diglyme-based liquid electrolytes into the IPN-SPEs, a gel electrolyte was formed with excellent electrochemical properties and high conductivity at room temperature. LMBs using such electrolytes delivered a capacity of over 170 mAh g–1with excellent Coulombic efficiency and cycling stability. Our study demonstrated that the IPN-based SPEs are promising to address the challenges of high voltage secondary batteries.