All-Solid-State Lithium Batteries: Li+-Conducting Ionomer Binder for Dry-Processed Composite Cathodes

作者：Seung-Bo Hong, Young-Jun Lee, Un-Hyuck Kim, Cheol Bak, Y. Lee, Woosuk Cho, H. Hah, Yang‐Kook Sun, Dong‐Won Kim · 发表于：ACS Energy Letters · 年份：2022 · DOI：10.1021/acsenergylett.1c02756 · 被引用次数：136

All-solid-state lithium batteries (ASSLBs) are considered promising alternatives to current lithium-ion batteries as their use poses less of a safety risk. However, the fabrication of composite cathodes by the conventional slurry (wet) process presents technical challenges, such as limited stability of sulfide electrolytes against organic solvents and the increase of ionic resistance due to the use of insulating polymer binder. Herein, we develop a composite cathode fabricated using a solvent-free (dry) process. The composite cathode is prepared with a Liconducting ionomer binder, poly(tetrafluoroethylene-co-perfluoro(3-oxa-4-pentenesulfonic acid)) lithium salt. The ionomer facilitates Li transport and ensures good interfacial contact between the active material (LiNi0.7Co0.1Mn0.2O2), conducting carbon, and solid electrolyte (Li6PS5Cl) during cycling. Consequently, an ASSLB featuring a composite cathode with an ionomer delivers a high discharge capacity of 180.7 mAh g−1 (3.05 mAh cm−2) at 0.1 C and demonstrates stable cycling performance, retaining 90% of its initial capacity after 300 cycles at 0.5 C. Global warming and the resulting environmental regulations are driving the development of environmentally friendly transportation systems, for example, electric vehicles (EVs) employing lithium-ion batteries (LIBs). However, the use of LIBs poses a significant safety risk as they typically contain a highly flammable liquid electrolyte, which can lead to a fire or an explosion u...