Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical Engineering Tsinghua University Beijing 100084 P.R. China

Advanced Research Institute of Multidisciplinary Science Beijing Institute of Technology Beijing 100081 P.R. China

固态锂（Li）金属电池（SSLMB）由于安全性强和能量密度高而成为能量存储领域的研究热点。但是，SSLMB遭受的故障包括枝晶引起的短路和接触损耗引起的高阻抗，这与锂电镀/剥离动力学密切相关，并阻碍了SSLMB的实际应用。SSLMB中没有电池故障的锂电池循环的最大可承受电流密度通常定义为临界电流密度（CCD）。因此，CCD是SSLMB应用的重要参数，可以帮助确定固态电池Li动力学的速率确定步骤。在这里，从基本的热力学和动力学原理，失效机理，对CCD的识别以及影响CCD性能的影响因素进行了系统的综述。基于这些基本理解，提出了一系列有关SSLMB未来研究的策略和展望，以期为实际的SSLMB增加CCD。 Solid‐state lithium (Li) metal batteries (SSLMBs) have become a research hotspot in the energy storage field due to the much‐enhanced safety and high energy density. However, the SSLMBs suffer from failures including dendrite‐induced short circuits and contact‐loss‐induced high impedance, which are highly related to the Li plating/stripping kinetics and hinder the practical application of SSLMBs. The maximum endurable current density of lithium battery cycling without cell failure in SSLMB is generally defined as critical current density (CCD). Therefore, CCD is an important parameter for the application of SSLMBs, which can help to determine the rate‐determining steps of Li kinetics in solid‐state batteries. Herein, the theoretical and practical meanings for CCD from the fundamental thermodynamic and kinetic principles, failure mechanisms, CCD identifications, and influence factors for improving CCD performances are systematically reviewed. Based on these fundamental understandings, a series of strategies and outlooks for future researches on SSLMB are presented, endeavoring on increasing CCD for practical SSLMBs.