Open AccessElectrochemical Response of Cold‐Sintered Cathode‐Hybrid Electrolyte Bilayers: Deep Insights into the Determining Kinetic Mechanisms via Operando Electrochemical Impedance Characterization
Author(s) -
FerrerNicomedes Sergio,
MormeneoSegarra Andrés,
VicenteAgut Nuria,
BarbaJuan Antonio,
GarciaBelmonte Germà
Publication year - 2025
Publication title -
energy and environmental materials
Language(s) - English
Resource type - Journals
ISSN - 2575-0356
DOI - 10.1002/eem2.12886
Subject(s) - electrochemistry , electrolyte , cathode , materials science , electrical impedance , kinetic energy , characterization (materials science) , electrode , dielectric spectroscopy , chemical engineering , analytical chemistry (journal) , chemistry , nanotechnology , chromatography , electrical engineering , physics , quantum mechanics , engineering
This study demonstrates the successful fabrication of solid‐state bilayers using LiFePO₄ (LFP) cathodes and Li 1.3 Al 0.3 Ti 1.7 (PO4) 3 (LATP)‐based Composite Solid Electrolytes (CSEs) via Cold Sintering Process (CSP). By optimizing the sintering pressure, it is achieved an intimate contact between the cathode and the solid electrolyte, leading to an enhanced electrochemical performance. Bilayers cold sintered at 300 MPa and a low‐sintering temperature of 150 °C exhibit high ionic conductivities (0.5 mS cm −1 ) and stable specific capacities at room temperature (160.1 mAh g −1 LFP at C/10 and 75.8 mAh g −1 LFP at 1 C). Moreover, an operando electrochemical impedance spectroscopy (EIS) technique is employed to identify limiting factors of the bilayer kinetics and to anticipate the overall electrochemical behavior. Results suggest that capacity fading can occur in samples prepared with high sintering pressures due to a volume reduction in the LFP crystalline cell. This work demonstrates the potential of CSP to produce straightforward high‐performance bilayers and introduces a valuable non‐destructive instrument for understanding and avoiding degradation in solid‐state lithium‐based batteries.