Enhanced Lithium-Ion Transport at Solid–Liquid Electrolyte Interface via Inorganic-Rich Layer for Quasi-Solid Electrolytes
Junosuke Kondo, Yuta Iga, Kazushi Otani, Ryota Noba, Hideaki Hikosaka, Yasuyuki Kondo, Yu Katayama, Yuki Yamada
Abstract
High Resolution Image Download MS PowerPoint Slide The development of quasi-solid electrolytes composed of garnet-type Li 7 La 3 Zr 2 O 12 (LLZO) with a liquid electrolyte represents a promising approach for safer lithium-ion batteries. However, a major challenge has been the inefficient transport of Li + across the LLZO-liquid electrolyte interface due to the formation of a resistive interfacial layer. Herein, we systematically studied the relationship between interfacial Li + transport and interfacial layer compositions controlled by heat treatment. We demonstrate that optimum heat treatment transforms the interfacial layer composition from organic-rich to inorganic-rich (including Li 2 CO 3 ) without increasing the thickness, which significantly reduces the interfacial resistance and lowers the activation energy of Li + transport. Furthermore, we achieved an enhanced limiting current density in a quasi-solid electrolyte using heat-treated LLZO. On this basis, an inorganic-rich interfacial layer, particularly with Li 2 CO 3, is crucial for achieving efficient Li + transport at solid–liquid electrolyte interfaces, offering an important guideline for developing advanced quasi-solid electrolytes.