Interrupted anion-network enhanced Li+-ion conduction in Li3+yPO4Iy
Interrupted anion-network enhanced Li+-ion conduction in Li3+yPO4Iy
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DOI：
10.1016/j.ensm.2022.06.026
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发表时间：
2022-10-01
影响因子：
20.4
通讯作者：
Hu，Yan-Yan
中科院分区：
文献类型：
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作者：
Patel，Sawankumar V.;Truong，Erica;Hu，Yan-Yan
要使固态电池在能量密度和成本上超越当前的锂离子电池技术，使用低成本前驱体和可扩展工艺生产高性能固体电解液是关键。在这项研究中，我们展示了使用廉价的低电导率10−6ms/cm的Li3PO4，通过设计阴离子亚晶格，将其转变为离子电导率为≥0.15ms/cm的快速Li+离子导体。核磁共振弛豫测量表明，I−阴离子破坏了Li3PO4中有序的PO4 3−网络，破坏了Li+-PO4 3−相互作用的稳定性，释放了具有增强Li+迁移率的Li+离子.当PO4 3−/I−=1时，Li+离子与PO4 3−和I−在扩散路径上停留的时间相等，没有被俘获，电导率和活化能最大.示踪交换核磁共振研究表明，当y≠为1时，Li4PO4I的导电性高于Li3+yPO4Iy。通过稳定纯玻璃相Li4PO4I，可以进一步提高导电性。总之，本研究表明了一种显著提高离子导电性的有效而普遍的策略，以创造出廉价的高性能固体电解质。
For solid-state batteries to outperform the current lithium-ion battery technology in energy density and cost, high-performance solid electrolytes produced using low-cost precursors and scalable processes are the key. In this study, we demonstrate using inexpensive Li 3 PO 4 of low conductivity 10− 6 mS/cm and turning it into a fast Li+-ion conductor, with an ionic conductivity of≥ 0.15 mS/cm, by engineering the anion sublattice. I− anions are used to interrupt the ordered PO 4 3− network in Li 3 PO 4, which destabilizes Li+-PO 4 3− interaction and liberates Li+-ions with enhanced Li+ mobility as evidenced by NMR relaxometry measurements. The optimal conductivity and activation energy are achieved when PO 4 3−/I−= 1, in which Li+-ions spend equal time with PO 4 3− and I− on their diffusion paths without being trapped. Tracer-exchange NMR shows that Li 4 PO 4 I is more conductive than Li 3+ y PO 4 I y when y≠ 1. Further conductivity enhancement is possible by stabilizing pure-phase glassy Li 4 PO 4 I. Overall, this study shows an effective and general strategy to significantly enhance ion conduction for creating inexpensive solid electrolytes with high performance.