STEM-EELS Spectrum Imaging of an Aerosol-Deposited NASICON-Type LATP Solid Electrolyte and LCO Cathode Interface
STEM-EELS Spectrum Imaging of an Aerosol-Deposited NASICON-Type LATP Solid Electrolyte and LCO Cathode Interface
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DOI：
10.1021/acsaem.1c02512
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发表时间：
2021-12-23
影响因子：
6.4
通讯作者：
Iriyama, Yasutoshi
中科院分区：
文献类型：
--
作者：
Muto, Shunsuke;Yamamoto, Yuta;Iriyama, Yasutoshi
全固态蓄电池（ASSB）是下一代电动汽车大功率电源和储能装置的理想选择。ASSB提供优异的安全性和高能量密度;然而，由于在高温下的固-固接触反应，正极和固体电解质之间的高界面电阻限制了它们的应用。为了解决这些问题，热退火对钠超离子导体（NASICON）型Li1.3Al0.3Ti1.7（PO 4）（3）（LATP）固体电解质和LiCoO 2（LCO）阴极之间的界面结构的影响进行了实验研究。具体地，通过结合扫描透射电子显微镜和电子能量损失谱进行光谱成像。沉积态样品中LATP和LCO之间形成了亚稳态的低密度过渡层。在250-300 ℃的热退火后，界面电阻显著降低，这主要归因于在该温度范围内的结构恢复。然而，在400摄氏度的热退火导致增加的界面电阻，由于在LATP/LCO界面处形成的Co 3 O 4样尖晶石阻挡层。这些研究结果提供了有价值的见解的电子性能的ASSB复合材料的调查，并与理论预测的锂和O之间的转移，由于热退火。
All-solid-state batteries (ASSBs) are promising candidates for application as next-generation high-power supply and storage devices in electric vehicles. ASSBs offer excellent safety and a high energy density; however, the high interfacial resistance between the positive electrode and solid electrolyte due to solid-solid contact reactions at elevated temperatures limits their applications. To address these issues, the effect of thermal annealing on the interfacial structure between a sodium super ionic conductor (NASICON)-type Li1.3Al0.3Ti1.7(PO4)(3) (LATP) solid electrolyte and a LiCoO2 (LCO) cathode in an ASSB fabricated by aerosol deposition was investigated experimentally. Specifically, spectrum imaging was conducted by combining scanning transmission electron microscopy and electron energy loss spectroscopy. Metastable degraded low-density transition layers were formed between LATP and LCO in the as-deposited sample. A significant reduction in interfacial resistance was achieved after thermal annealing at 250-300 degrees C, which was mainly attributed to structural recovery in this temperature range. However, thermal annealing at 400 degrees C resulted in increased interfacial resistance due to the formation of a Co3O4-like spinel blocking layer at the LATP/LCO interface. These findings provided valuable insights into the electronic properties of the ASSB composite under investigation and were consistent with theoretical predictions of Li and O transfer between the layers due to thermal annealing.