锂离子电池原位透射电镜方法的综合比较

Comprehensive comparison of in-situ transmission electron microscopy methods for lithium-ion batteries

锂离子电池(LIB)技术已成为目前最重要、最有前途的储能技术之一,广泛应用于便携式电子设备和电动汽车等领域。然而,随着人们对能源的需求愈发强烈,发展下一代更高能量密度和更长循环寿命的锂离子电池刻不容缓,这就需要更加深入地理解锂离子电池在循环过程中内部结构的演化。作为一种能够对精细结构进行多方面表征的工具,原位透射电子显微镜(in situ TEM)拥有原子尺度的高空间分辨率,同时可以施加外电场实现实时观测和分析充放电过程中电极材料的微观结构演化和相变机制。因此,该原位技术在锂离子电池研究方向得到了广泛的关注和快速发展。其中两种主要的研究体系,开放池(open cell)与液体池(liquid cell)均为研究的热点却一直以来缺少详细的对比总结。鉴于此,本文详细介绍了原位透射电子显微镜开放池(open cell)与液体池(liquid cell)的内部结构,并将其在锂离子电池正极、负极和SEI形成与锂枝晶生长等领域的相关研究举例进行综合分析与对比,最后详细总结二者各自的适用范围与局限性,以期对未来两种原位透射电镜技术的应用提供指导。

Due to its high energy density,the lithium ion battery(LIB)has become increasingly significant in portable electronic devices and electric vehicles.However,the growing demand for energy consumption highlights the need to develop next-generation LIBs with higher capacity and longer lifespan.Therefore,it is essential to understand the micro-structure evolution of lithium-ion batteries during cycling.In-situ transmission electron microscopy is a valuable tool to detect the structure evolution of electrode materials in real time,benefiting from its ultrahigh spatial resolution.In the LIB field,in-situ TEM technique has received considerable attention and developed rapidly due to its ability to study the phase transition and degradation mechanisms during charging and discharging processes.Despite their popularity,there is a lack of detailed comparison and summary between the two main in-situ devices,i.e.,open cell and liquid cell.The internal structure of open cell and liquid cell inside in-situ transmission electron microscopy is introduced in detail hereafter,followed by a comprehensive analysis and comparison of practical examples in the fields of positive electrode,negative electrode,SEI formation,and lithium dendrite growth in LIBs.In conclusion,the paper provides a summary of their applications and limitations to guide the future development of these two in-situ transmission electron microscopy techniques.