Detrimental effect of high-temperature storage on sulfide-based all-solid-state batteries

Abstract

The all-solid-state battery (ASSB) has become one of the most promising next-generation battery systems, since the aspect of safety has emerged as a crucial criterion for new large-scale applications such as in electric vehicles. Despite the recent remarkable progress in the performance enhancement, the real-world implementation of the ASSB still requires full comprehension/evaluation of its properties and performance under various practical operational conditions. Unlike batteries employed in conventional electronic devices, those in electric vehicles—the major application that the ASSB is expected to be employed—would be exposed to wide temperature variations (−20 to ∼70 °C) at various states of charges due to their outdoor storage and irregular discharge/rest/charge conditions depending on vehicle drivers' usage patterns. Herein, we investigate the reliability of a Li6PS5Cl-based ASSB system in practically harsh but plausible storage conditions and reveal that it is vulnerable to elevated-temperature storage as low as 70 °C, which, in contrast to the common belief, causes significant degradation of the electrolyte and consequently irreversible buildup of the cell resistance. It is unraveled that this storage condition induces the decomposition of Li6PS5Cl in contact with the cathode material, involving the SOx gas evolution particularly at charged states, which creates a detrimental porous cathode/electrolyte interface, thereby leading to the large interfacial resistance. Our findings indicate that the stability of the solid electrolyte, which has been believed to be failsafe, needs to be carefully revisited at various practical operational conditions for actual applications in ASSBs.

Zero-Strain Cathodes for Lithium-Based Rechargeable Batteries: A Comprehensive Review

“…In all-solid-state batteries (ASSBs), the issues associated with volumetric change of CAMs are more detrimental . In addition to cracking and fracture in cathode particles as in the LIB system, the so-called “breathing” cathodes cause the separation of the solid electrolyte and CAM and also endanger the structural integrity of the system in a volume-constrained and pressurized setup. ,− Therefore, the volumetric change of the cathode has a significant effect on battery performance, such as long-term stability and discharge capacity, posing a great challenge for progress toward high energy density batteries. Therefore, it is desirable to employ cathode materials that undergo negligible volumetric changes upon Li insertion/extraction.…”

A Full Oxide-Based Solid-State Lithium Battery and Its Unexpected Cathode Degradation Mechanism

“…The robust cycle attributes of these oxide ASSBs enabled us to explore what intrinsically causes capacity fading of cathode composites in ASSBs, an area where previous studies have been lacking. While earlier research conducted on sulfide- and halide-based ASSB has suggested that the cathode degradation primarily arises from the deterioration of the interface between CAM and solid electrolyte due to repeated volume change of CAM during cycle, − we discover that residual stress on CAM unexpectedly plays a critical role in the cathode degradation in oxide-based ASSBs. It is proposed that the cosintering of two oxides results in significant thermal mismatch during cooling, and this residual stress exacerbates the mechanical degradation of both the interface and CAM itself during the electrochemical cycles.…”

Monolithic 100% Silicon Wafer Anode for All-Solid-State Batteries Achieving High Areal Capacity at Room Temperature

“…The recent development of portable devices, electric vehicles, and large-scale energy storage systems has significantly increased the demand for safer and more energy-dense batteries. − All-solid-state batteries (ASSBs) utilizing sulfide-based electrolytes provide an ideal geometry to attain a higher energy density and improved safety compared with conventional lithium-ion batteries (LIBs) using flammable organic liquid electrolytes. − …”