SnF₂‐Induced Multifunctional Interface‐Stabilized Li_5.5PS_4.5Cl_1.5‐Based All‐Solid‐State Lithium Metal Batteries

Abstract

Compared to traditional lithium‐ion batteries with liquid electrolytes, all‐solid‐state lithium batteries have attracted extensive attention due to their heightened safety and energy density. Lithium argyrodite materials are promising solid electrolytes (SE) due to their high ionic conductivity, low grain boundary resistance, and favorable mechanical properties. However, the poor chemical/electrochemical stability of lithium argyrodite electrolytes toward the bare lithium metal anode inhibits their applications in all‐solid‐state lithium metal batteries (ASSLMBs). Here, Li‐SnF2 composite anodeswas used to induce the formation of solid electrolyte interphase (SEI) composed of LiCl, LiF, and Li22Sn5 at the Li/SE interface. The high interface energy barriers for LiF and LiCl induces the uniform deposition of lithium ions, thus hindering the growth of lithium dendrites. Meanwhile, the fast Li‐ion diffusion coefficient of the Li22Sn5 alloy accelerates Li‐ion migration across the interface section. The symmetrical cell exhibits stable cycling performance over long durations over 300 h at 0.5 mA cm−2. Moreover, the LiNbO3@NCM712/Li5.5PS4.5Cl1.5/Li‐10%SnF2 battery delivers a high initial discharge capacity of 170.9 mAh g−1 at 0.1C and retains 72.9% of its original capacity after 500 cycles at 0.5C. The facial approach for Li‐SnF2 composite anode enables the production of ASSLMBs with superior electrochemical performance.

Performance Improvement of Argyrodite Solid Electrolyte for All-Solid-State Battery Using Wet Process

“…Sulfide-based solid electrolytes like Li 6 PS 5 Cl are generally prepared by annealing after mechanical milling. C.W Nan group and M. Wagemaker group reported the Li 6 PS 5 Cl electrolyte with an ionic conductivity of 3.15 × 10 –3 and 4.96 × 10 –3 S cm –1 . , Furthermore, research has been reported from various groups aiming to enhance the performance by doping Sn, Y, Br, N, and other elements into the argyrodite structure. − However, the dry ball milling process takes a long time, and it causes inhomogeneity in the composition and shape of the mixture due to the adhesion of the precursors . As a way to solve this problem, there is a solid electrolyte manufacturing process using a wet process that adds an organic solvent to existing materials …”

Niobium sulfide nanocomposites as cathode materials for all-solid-state lithium batteries with enhanced electrochemical performance

“…The compatibility between cathodes and sulfide electrolytes is also vital for high-performance all-solid-state batteries. 14–17 In contrast to transition metal oxides, transition metal polysulfides are more compatible with sulfide solid electrolytes because of their similar chemical potential, thus avoiding the formation of space charge layers. 18,19 In addition, the majority of transition metal polysulfides undergo redox reactions driven by both cations and anions during the charge–discharge process, thus improving reversible specific capacity.…”

Dendrite-Free Li5.5PS4.5Cl1.5-Based All-Solid-State Lithium Battery Enabled by Grain Boundary Electronic Insulation Strategy through In Situ Polymer Encapsulation

“…This creates stress in these pores, causing cracks and ultimately causing lithium dendrites to permeate the entire battery, resulting in battery failure. ,− Additionally, due to the inherent immobility of the sulfide SSEs, failure is inevitable around an area with contact defects at the interface between sulfide SSEs and the Li anode. During Li stripping/deposition, the contact failure at the interface between sulfide SSEs and the Li anode increases the local current density, which leads to the rapid growth of Li dendrites, respectively. − On the other hand, the electronic conductivity of sulfide SSEs is not negligible, which also leads to the growth of lithium dendrites and undesirable interfacial side reactions, ultimately passivating the SSEs/anode interface or even causing a short circuit. , Therefore, improving the interfacial contact between sulfide SSEs and the Li–metal anode and reducing the electronic conductivity of sulfide SSEs are crucial for achieving high-performance ASSLBs. To achieve both of these goals, an effective solution is to combine SSEs with polymeric materials.…”