All-solid-state lithium batteries (ASSLBs) have the potential to increase energy density, improve safety, and allow for lower manufacturing costs compared to conventional, liquid-based Li-ion batteries. The thickness of solid electrolyte (SE) layer dictates the cell-level energy density and it is desirable to make the SE layer as thin as possible while maintaining uniformity and defect-free. Manufacturing a high-quality, thin sulfide SE layer at large-scale, however, is challenging. Previous studies have addressed the compatibility of materials used for manufacturing thin sulfide SE films, paving the way for further investigation of processing conditions and film quality. Here we report a strong correlation between the solid loading of dispersions and the quality of tape-casted thin sulfide SE films. We also demonstrate a method for quantifying the quality of thin SE films by observing both pin-hole defects and larger heterogeneous agglomerations of particles in the films. Our thin sulfide SE films containing ∼5 wt% binder are defect-free and show similar ionic conductivity compared to a cold-pressed, binder-free, thick SE pellet, resulting in an ∼11X reduction of area specific resistance. This work on the solid loading of the dispersion used in a scalable tape casting process provides insight for manufacturing high-quality, thin sulfide SE films and to increase the cell-level energy density of ASSLB.

与传统的液基锂离子电池相比，全固态锂电池（ASSLB）具有提高能量密度，提高安全性并降低制造成本的潜力。固体电解质（SE）层的厚度决定了电池级的能量密度，希望在保持均匀性和无缺陷的同时使SE层尽可能薄。然而，大规模地制造高质量的薄的硫化物SE层是具有挑战性的。先前的研究已经解决了用于制造硫化物SE薄膜的材料的相容性，为进一步研究加工条件和薄膜质量铺平了道路。在这里，我们报告了分散体的固含量与流延流延的薄型硫化物SE薄膜的质量之间存在很强的相关性。我们还展示了一种通过观察针孔缺陷和薄膜中较大的颗粒异质团聚来量化SE薄膜质量的方法。与冷压，无粘合剂的厚SE颗粒相比，我们的含〜5 wt％粘合剂的硫化物SE薄膜无缺陷，并且显示出相似的离子电导率，从而使面积比电阻降低了约11倍。这项针对可伸缩带式流延工艺中使用的分散体的固含量的工作为制造高质量，薄的硫化物SE薄膜以及提高ASSLB的电池级能量密度提供了见识。与冷压，无粘合剂的厚SE颗粒相比，我们的含〜5 wt％粘合剂的硫化物SE薄膜无缺陷，并且显示出相似的离子电导率，从而使面积比电阻降低了约11倍。这项针对可伸缩带式流延工艺中使用的分散体的固含量的工作为制造高质量，薄的硫化物SE薄膜以及提高ASSLB的电池级能量密度提供了见识。与冷压，无粘合剂的厚SE颗粒相比，我们的含〜5 wt％粘合剂的硫化物SE薄膜无缺陷，并且显示出相似的离子电导率，从而使面积比电阻降低了约11倍。这项针对可伸缩带式流延工艺中使用的分散体的固含量的工作为制造高质量，薄的硫化物SE薄膜以及提高ASSLB的电池级能量密度提供了见识。