Electronic Conductivity of Lithium Solid Electrolytes
Electronic Conductivity of Lithium Solid Electrolytes
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DOI：
10.1002/aenm.202204098
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发表时间：
2023-03
影响因子：
27.8
通讯作者：
Bowen Shao;Yonglin Huang;Fudong Han
中科院分区：
文献类型：
--
作者：
Bowen Shao;Yonglin Huang;Fudong Han
虽然人们致力于提高锂固体电解质(SES)的离子导电性，但电子输运对固体电池(SSB)的日历寿命、能量密度和循环稳定性具有重要作用，但研究较少。本文报道了Li3PS4、Li7La3Zr2O12和Li3YCl6三种具有代表性的SES的电子电导。据报道，传统的测量方法高估了Se的电子电导。通过回顾使用双阻断电极电池的直流极化和Hebb-Wagner方法，给出了它们的不准确性来源，并强调了SE的阳极分解是高估结果的关键来源。在电极选择和数据解释方面也提出了改进，以接近Se的本征电子电导率。还提出了一种两步极化方法来估算在测量过程中分解的硫化物的电子电导率。用改进的方法测量，所有Se的电子电导都比报道的值低一个或两个数量级。尽管如此，硫化物的电子传导性似乎仍然相当高，能够使SSB具有长达10年的日历寿命，这突显了对锂Se中电子输运进行更仔细研究的迫切需要。
While significant efforts are being devoted to improving the ionic conductivity of lithium solid electrolytes (SEs), electronic transport, which has an important role in the calendar life, energy density, and cycling stability of solid‐state batteries (SSBs), is rarely studied. Here, the electronic conductivities of three representative SEs, including Li3PS4, Li7La3Zr2O12, and Li3YCl6, are reported. It is reported that the electronic conductivities of SEs are overestimated from the conventional measurements. By revisiting direct current polarizations using two‐blocking‐electrode cells and the Hebb‐Wagner approach, their sources of inaccuracy are provided and the anodic decomposition of SE is highlighted as the key source for the overestimated result. Modifications in the electrode selection and data interpretation are also proposed to approach the intrinsic electronic conductivity of SEs. A two‐step polarization method is also proposed to estimate the electronic conductivity of sulfides that decompose during measurement. Measured by the modified approach, the electronic conductivities of all SEs are one or two orders of magnitude lower than the reported value. Despite that, the electronic conductivity of sulfides seems to be still quite high to enable SSBs with a long calendar life of >10 years, highlighting the critical need for a more careful study of electronic transport in lithium SEs.