Liquid-involved synthesis and processing of sulfide-based solid electrolytes, electrodes, and all-solid-state batteries

Impact of Solvent Treatment of the Superionic Argyrodite Li6PS5Cl on Solid‐State Battery Performance

“…In addition to inherent limitations to energy density, [ 2 ] safety issues due to the liquid electrolyte (leakage/bursting) are also concerning, especially when it comes to applications in electric vehicles. The all‐solid‐state battery (ASSB), utilizing a solid electrolyte (SE), tackles these disadvantages by eliminating the flammability risks and providing a barrier to Li dendrite growth that plagues liquid electrolyte systems, [ 2–6 ] allowing the use of Li metal anodes to achieve the maximum energy density. These battery systems can provide reasonable power/energy density with highly conductive solid‐state electrolytes developed over the past decades.…”

“…These battery systems can provide reasonable power/energy density with highly conductive solid‐state electrolytes developed over the past decades. [ 2–4,7 ] Nevertheless, for commercial production of ASSBs, scalable synthesis and processing routes for the SE are crucial. Liquid‐phase synthesis has thus gained interest in recent years, [ 8–13 ] as well as solvent‐based processing of the electrolyte into separators, [ 14–17 ] or finished cathode composites.…”

“…Liquid‐phase synthesis has thus gained interest in recent years, [ 8–13 ] as well as solvent‐based processing of the electrolyte into separators, [ 14–17 ] or finished cathode composites. [ 3,5 ] This is either done as a slurry process (where the electrolyte is not dissolved) for mixing or as an infiltration/coating process (where the electrolyte is dissolved), with the benefit of allowing for intimate contact of the materials. [ 18–22 ] For slurry processing, as opposed to dry mixing of components, [ 23–27 ] a binder is generally required, and the performance of the cathode is often reduced (reductions in conductivity alone are often observed after exposure to seemingly inert solvents).…”

Cathode–Sulfide Solid Electrolyte Interfacial Instability: Challenges and Solutions

“…Slurry methods disperse cathode particles and coating precursors into a solvent following by drying and calcination steps as shown in Figure 1C. (Jung et al, 2018;Xu et al, 2019). Spray coating consists of preparing the coating material precursor solution and spraying it onto the active material particles, followed by heat treatments to achieve the desired form of the coating layer.…”

“…Although issues such as air-stability, moisture stability, dendrite growth, and thermal runaway have yet to be completely resolved, enabling sulfide ASSBs rests on stabilizing the electrode/ electrolyte interfaces (Muramatsu et al, 2011;Han et al, 2018;Chen et al, 2020;. Practical issues pertaining to processability and scalability such as the adaptability of SSEs to current roll-to-roll manufacturing and the drops in ionic conductivity commonly observed during slurry processing must also be considered in lab and pilot scale research efforts (Xu et al, 2019). However, fundamental understanding of the cathode-sulfide electrolyte interface has been a tremendous challenge and remains elusive.…”