Bilayer Halide Electrolytes for All-Inorganic Solid-State Lithium-Metal Batteries with Excellent Interfacial Compatibility

Abstract

Inorganic solid-state electrolytes (ISSEs) have been extensively researched as the critical component in all-solid-state lithium-metal batteries (ASSLMBs). Many ISSEs exhibit high ionic conductivities up to 10 −3 S cm −1 . However, most of them suffer from poor interfacial compatibility with electrodes, especially lithium-metal anodes, limiting their application in high-performance ASSLMBs. To achieve good interfacial compatibility with a high-voltage cathode and a lithium-metal anode simultaneously, we propose Li 3 InCl 6 /Li 2 OHCl bilayer halide ISSEs with complementary advantages. In addition to the improved interfacial compatibility, the Li 3 InCl 6 /Li 2 OHCl bilayer halide ISSEs exhibit good thermal stability up to 160 °C. The Li-symmetric cells with sandwich electrolytes Li 2 OHCl/Li 3 InCl 6 /Li 2 OHCl exhibit long cycling life of over 300 h and a high critical current density of over 0.6 mA cm −2 at 80 °C. Moreover, the all-inorganic solidstate lithium-metal batteries (AISSLMBs) LiFePO 4 −Li 3 InCl 6 /Li 3 InCl 6 /Li 2 OHCl/Li fabricated by a facile cold-press method exhibit good rate performance and long-term cycling stability that stably cycle for about 3000 h at 80 °C. This work presents a facile and cost-effective method to construct bilayer halide ISSEs, enabling the development of high-performance AISSLMBs with good interfacial compatibility and thermal stability.

Halide-sulfide bilayer electrolytes for LiFePO4-based all-solid-state batteries

“…24 Nevertheless, this result is inconsistent with previous reports, in which LZC was found to be incompatible with lithium anodes. [32][33][34] Thus, constructing a benign interface between cathode, electrolyte, and anode is key to achieving low-cost and high-safety LFP-based ASSLBs.…”

Thin Free-Standing Sulfide/Halide Bilayer Electrolytes for Solid-State Batteries Using Slurry Processing and Lamination

“…To overcome the challenges associated with polymer SEs, researchers have explored nanoscale coatings to improve the interfacial stability of oxide or sulfide SEs against Li metal anodes. − However, nanofabrication methods have inherent challenges associated with scalable manufacturing and mechanical durability. In comparison, there have been fewer reports of “bulk” ceramic–ceramic bilayers with thicknesses in the range of tens of μm for each layer in the literature. − Furthermore, the methodologies reported to date often require an investment in new manufacturing infrastructure because they do not use well-established Li-ion battery fabrication methods, such as slurry casting, , or they have required the incorporation of a polymer scaffold . Therefore, to further accelerate the commercialization of SSBs, there is a need to develop novel manufacturing pathways to fabricate thin-film (<100 μm) bilayer ceramic–ceramic SEs with improved stability and scalability, while maintaining compatibility with the manufacturing infrastructure currently used for Li-ion batteries …”