Interphase Morphology between a Solid-State Electrolyte and Lithium Controls Cell Failure
Interphase Morphology between a Solid-State Electrolyte and Lithium Controls Cell Failure
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DOI：
10.1021/acsenergylett.9b00093
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发表时间：
2019-02-01
影响因子：
22
通讯作者：
McDowell, Matthew T.
中科院分区：
文献类型：
--
作者：
Lewis, John A.;Cortes, Francisco Javier Quintero;McDowell, Matthew T.
许多固态电解质（SSE）和锂金属之间的界面是（电）化学不稳定的，并且需要改进对界面转变如何影响电化学降解的理解，以稳定这些界面，从而为电池提供更广泛的可行SSE。本文采用透射电子显微镜原位观察和非原位技术研究了Li1.4Al0.4Ge1.6（PO 4）（3）（LAGP）电解质与锂离子界面的电化学反应过程。锂与LAGP的反应导致非晶化和体积膨胀，这引起SSE的机械应力和断裂沿着，阻抗大幅增加。演化的界面在高电流下具有不均匀的形态，这导致加速的化学机械失效。这项工作表明，在SSE/Li界面的反应的电流依赖性在确定化学机械降解机制中起着至关重要的作用，与理解和控制各种各样的SSE材料与不稳定的界面降解的影响。
The interfaces between many solid-state electrolytes (SSEs) and lithium metal are (electro)chemically unstable, and improved understanding of how interfacial transformations influence electrochemical degradation is necessary to stabilize these interfaces and therefore enable a wider range of viable SSEs for batteries. Here, the (electro)chemical reaction processes that occur at the interface between Li1.4Al0.4Ge1.6(PO4)(3) (LAGP) electrolyte and lithium are studied using in situ transmission electron microscopy and ex situ techniques. The reaction of lithium with LAGP causes amorphization and volume expansion, which induce mechanical stress and fracture of the SSE along with a massive increase in impedance. The evolved interphase has a nonuniform morphology at high currents, which causes accelerated chemo-mechanical failure. This work demonstrates that the current-dependent nature of the reaction at the SSE/Li interface plays a crucial role in determining chemo-mechanical degradation mechanisms, with implications for understanding and controlling degradation in a wide variety of SSE materials with unstable interfaces.