Deep Eutectic Interlayer Design for Stability Enhancement in LLZTO Solid-State Lithium Batteries

TY - JOUR

T1 - Deep Eutectic Interlayer Design for Stability Enhancement in LLZTO Solid-State Lithium Batteries

AU - Long, Sihong

AU - Gui, Boshun

AU - Li, Chengjie

AU - Yang, Binbin

AU - Sun, Lipu

AU - Zhan, Yu

AU - Huang, Chuhuai

AU - Tian, Jianing

AU - Wu, Feng

AU - Chen, Nan

AU - Chen, Renjie

N1 - Publisher Copyright: © 2025 Wiley-VCH GmbH.

PY - 2026/1/26

Y1 - 2026/1/26

N2 - Li6.4La3Zr1.4Ta0.6O12 (LLZTO) is a typical inorganic garnet-type ceramic solid electrolyte. By combining LLZTO with polyacrylonitrile (PAN), a homogeneous composite electrolyte film can be obtained, which is self-supporting and can be directly used as a solid-state electrolyte. However, PAN and its composite electrolyte exhibit low ionic conductivity at room temperature and suffer from poor solid-solid interface contact with the lithium metal anode. Herein, a method of using succinonitrile (SN) deep eutectic electrolyte is proposed to modify the solid-state electrolyte interface, thereby preventing corrosion reactions and improving the Li+ transference number of the composite solid electrolyte (PALS) to 0.66. The introduction of the interface modification layer enables the formation of a stable and dense solid-electrolyte interphase (SEI) layer at the interface between the lithium anode and the solid-state electrolyte, reducing interfacial impedance and improving the ionic conductivity of the solid-state electrolyte. The Li/PALS/lithium iron phosphate (LFP) full cell exhibits an initial specific capacity of 147 mAh·g−1 at a 0.5 C rate, with 97.3% capacity retention after 190 cycles at room temperature. This work presents a novel approach to improving the interfacial contact between LLZTO and lithium metal anode, offering new insights for the design of fast-rate, safe, and durable solid-state electrolytes.

AB - Li6.4La3Zr1.4Ta0.6O12 (LLZTO) is a typical inorganic garnet-type ceramic solid electrolyte. By combining LLZTO with polyacrylonitrile (PAN), a homogeneous composite electrolyte film can be obtained, which is self-supporting and can be directly used as a solid-state electrolyte. However, PAN and its composite electrolyte exhibit low ionic conductivity at room temperature and suffer from poor solid-solid interface contact with the lithium metal anode. Herein, a method of using succinonitrile (SN) deep eutectic electrolyte is proposed to modify the solid-state electrolyte interface, thereby preventing corrosion reactions and improving the Li+ transference number of the composite solid electrolyte (PALS) to 0.66. The introduction of the interface modification layer enables the formation of a stable and dense solid-electrolyte interphase (SEI) layer at the interface between the lithium anode and the solid-state electrolyte, reducing interfacial impedance and improving the ionic conductivity of the solid-state electrolyte. The Li/PALS/lithium iron phosphate (LFP) full cell exhibits an initial specific capacity of 147 mAh·g−1 at a 0.5 C rate, with 97.3% capacity retention after 190 cycles at room temperature. This work presents a novel approach to improving the interfacial contact between LLZTO and lithium metal anode, offering new insights for the design of fast-rate, safe, and durable solid-state electrolytes.

KW - LLZTO/PAN composite solid electrolyte

KW - deep eutectic electrolyte

KW - interlayer design

KW - long cycling life

KW - solid-state lithium metal batteries

UR - https://www.scopus.com/pages/publications/105013779892

U2 - 10.1002/adfm.202513024

DO - 10.1002/adfm.202513024

M3 - Article

AN - SCOPUS:105013779892

SN - 1616-301X

VL - 36

JO - Advanced Functional Materials

JF - Advanced Functional Materials

IS - 8

M1 - e13024

ER -