Infiltration of Solution-Processable Solid Electrolytes into Conventional Li-Ion-Battery Electrodes for All-Solid-State Li-Ion Batteries
mediaposted on 2017-03-31, 00:00 authored by Dong Hyeon Kim, Dae Yang Oh, Kern Ho Park, Young Eun Choi, Young Jin Nam, Han Ah Lee, Sang-Min Lee, Yoon Seok Jung
Bulk-type all-solid-state lithium-ion batteries (ASLBs) have the potential to be superior to conventional lithium-ion batteries (LIBs) in terms of safety and energy density. Sulfide SE materials are key to the development of bulk-type ASLBs because of their high ionic conductivity (max of ∼10–2 S cm–1) and deformability. However, the severe reactivity of sulfide materials toward common polar solvents and the particulate nature of these electrolytes pose serious complications for the wet-slurry process used to fabricate ASLB electrodes, such as the availability of solvent and polymeric binders and the formation of ionic contacts and networks. In this work, we report a new scalable fabrication protocol for ASLB electrodes using conventional composite LIB electrodes and homogeneous SE solutions (Li6PS5Cl (LPSCl) in ethanol or 0.4LiI–0.6Li4SnS4 in methanol). The liquefied LPSCl is infiltrated into the tortuous porous structures of LIB electrodes and solidified, providing intimate ionic contacts and favorable ionic percolation. The LPSCl-infiltrated LiCoO2 and graphite electrodes show high reversible capacities (141 and 364 mA h g–1) at 0.14 mA cm–2 (0.1 C) and 30 °C, which are not only superior to those for conventional dry-mixed and slurry-mixed ASLB electrodes but also comparable to those for liquid electrolyte cells. Good electrochemical performance of ASLBs employing the LPSCl-infiltrated LiCoO2 and graphite electrodes at 100 °C is also presented, highlighting the excellent thermal stability and safety of ASLBs.
LPSCl-infiltrated LiCoO 2graphite electrodes showConventional Li-Ion-Battery Electrodesscalable fabrication protocolSulfide SE materialsLIB electrodesLi 6 PS 5 ClGood electrochemical performanceslurry-mixed ASLB electrodesAll-Solid-State Li-Ion Batteries Bulk-type all-solid-state lithium-ion batteriesASLB electrodes