Degradation of All-Solid-State Lithium-Sulfur Batteries with PEO-Based Composite Electrolyte

• Published in: Journal of electrochemical science and technology Vol. 13; no. 2; pp. 199 - 207
• Main Authors: Lee, Jongkwan, Heo, Kookjin, Song, Young-Woong, Hwang, Dahee, Kim, Min-Young, Jeong, Hyejeong, Shin, Dong-Chan, Lim, Jinsub
• Format: Journal Article
• Language: Korean
• Published: 2022
• Subjects: Lithium-Sulfur Batteries; Solid-State Electrolyte; Poly(Ethylene Oxide) (PEO); Li_7La_3Zr_2O_{12}$ (LLZO)
• ISSN: 2093-8551; 2288-9221

Lithium-sulfur batteries (LSBs) have emerged as a promising alternative to lithium-ion batteries (LIBs) owing to their high energy density and economic viability. In addition, all-solid-state LSBs, which use solid-state electrolytes, have been proposed to overcome the polysulfide shuttle effect while improving safety. However, the high interfacial resistance and poor ionic conductivity exhibited by the electrode and solid-state electrolytes, respectively, are significant challenges in the development of these LSBs. Herein, we apply a poly (ethylene oxide) (PEO)-based composite solid-state electrolyte with oxide Li7La3Zr2O12 (LLZO) solid-state electrolyte in an all-solid-state LSB to overcome these challenges. We use an electrochemical method to evaluate the degradation of the all-solid-state LSB in accordance with the carbon content and loading weight within the cathode. The all-solid-state LSB, with sulfur-carbon content in a ratio of 3:3, exhibited a high initial discharge capacity (1386 mAh g-1), poor C-rate performance, and capacity retention of less than 50%. The all-solid-state LSB with a high loading weight exhibited a poor overall electrochemical performance. The factors influencing the electrochemical performance degradation were revealed through systematic analysis.